YIG Filter Devices Product Selection Guide

YIG Filter Products
YIG
Filters
Introduction
Yttrium Iron Garnet (YIG) filters have
been used in military systems and commercial test equipment for over 30 years.
The extremely high unloaded “Qu” of the
YIG sphere (approximately 10,000) makes
it an ideal choice as the frequency-determining element for these electronically
tunable filters. Their excellent linearity,
low insertion loss, and broadband tuning
characteristics are ideal for applications
in the 0.5-40 GHz frequency range.
Bandpass filter applications include preselectors for radar warning and ELINT
(Electronic Intelligence) receivers in
the EW (Electronic Warfare) arena and
spectrum analyzers in the microwave
and commercial test equipment industry.
Band-reject filter applications include
“notching out” a particular signal for
ESM and ECM systems, and rejecting
signals in commercial test equipment
measurement set-ups.
YIG is a ferrite material that resonates at
a precise frequency when placed in a magnetic field. The frequency of resonance
is directly proportional to the strength
of the applied magnetic field. The high
reliability of YIG devices is excellent
for military applications. Their low loss,
wideband tuning, and excellent linearity
characteristics make them ideal for commercial test equipment applications such
as sweepers, synthesizers and spectrum
analyzers.
OFOISR App 06-S-1942
YIG Filters with low loss, wideband tuning, and excellent linearity characteristics
make them ideal for commercial test equipment applications
What is a YIG Filter?
A “YIG Filter” is an electronically tuned
filter whose center frequency can be varied
by changing the magnetic bias applied to
a resonator. Often, filter resonators are
realized using YIG material, although
YIG doped with other substances such
as Gallium or crystals of Lithium-Ferrite
or Nickel-Zinc are also widely used to
satisfy various requirements. Equipped
with integrated drivers (voltage-to-current
or digital word-to-current converters),
these filters combine many sophisticated
technologies, including crystal physics,
magnetics, and analog and digital design.
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Providing Customer Solutions
Using the highest level of technology and
manufacturing expertise is not enough.
We support our customers from preliminary design through installation.
Teledyne Microwave provides solutions to
customer requirements in three key areas:
Technical Support
Technical Notes with detailed discussions
of various aspects of YIG filter perfor-
mance, including tuning errors, driver
stability, and tuning speed.
Discussion prior to proposal ensures
that we offer a solution that will work in
the system and is producible at the rates
required. Our engineering personnel are
available to answer customer questions as
they arise.
Technical Proposals detail our solution so
that all system options are clear.
Customer Service
Feedback on delivery and technical progress during the design and manufacturing
periods after order placement.
Stringent Quality Assurance
All Teledyne components and subsystems
are designed, built and screened with the
highest quality standards available in the
industry. Teledyne Microwave is certified
to ISO-9001 & ISO-14001
Technology Features
In addition to the three key areas mentioned above, Teledyne Products believes
our level of technology distinguishes us
from other YIG vendors. Some of the key
technology features of Teledyne’s YIG
filter products include:
Proprietary Coupling Loop Technology
Both band-reject and bandpass filters are
designed using Teledyne’s proprietary
coupling loop technology. This CAD
technique entails extensive modeling and
characterization of the filter circuit at the
onset of the design phase. Using modified
filter modeling software, coupling coefficients are generated that precisely define
coupling loop properties and relationships
in the filter itself.
These coefficients are set by Teledyne
Products technicians who align the filters
using vector network analyzers to make
minute adjustments to match the computer designed coupling bandwidths. The net
result is a final set of coupling coefficients
that precisely match the characteristics of
the filter to the customers’ requirements.
As figure 1 shows, the coupling in a bandpass filter varies with tuned frequency,
even if the structures and resonators are
OFOISR App 06-S-1942
perfectly realized. The external bandwidth
is continuously varying with frequency.
Coupling bandwidth changes with frequency cause filter bandwidth growth and
poor VSWR as the tuned frequency increases. This results in degraded rejection
at key frequencies, such as the LO and
image frequencies of a superheterodyne
receiver, and increased mismatch loss and
ripple in the filter passband.
Teledyne proprietary loop technology
reduces coupling bandwidth changes
thus minimizing bandwidth growth,
and optimizing input match. This means
better control of spurious responses, improved sensitivity, flatter group delay, and
enhanced control of noise bandwidth in
receiver applications.
Among the benefits of using this technology in designing YIG filters:
•
The RF behavior of the filter can
be precisely controlled via its coupling loop characteristics. In particular, bandwidth growth, input
and output VSWR, and bandwidth
can be precisely set to meet system
requirements. Spurious responses are
controlled and minimized using these
techniques.
•
Filter performance, from unit to unit,
is replicated on a consistent basis.
•
Large quantities of filters can be produced to support customer production requirements since Teledyne’s
technology lends itself to efficient
manufacturing and results in YIG
filters that are inherently manufacturable. This is in contrast to the
“empirical” method that the majority
of YIG manufacturers use today, in
which a filter is simply built up and
“tweaked” until the desired performance is achieved.
Wide Instantaneous Bandwidths
Variations in group delay in the frontend of modern communications systems,
with their complex modulations and
dense channel spacing, cause degradation
measured as increased bit error rates and
higher noise power ratios. The complexity of the modulation alone requires
even wider instantaneous bandwidths.
Teledyne’s improved designs reduce mismatch effects and reduce delay distortion
due to crossing modes in the resonators,
and offer the widest bandwidths available
for communications applications. In addition, Teledyne’s 6-stage, or more, produc-
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Technology Features
Interstage
Coupling
Coefficients
Input / Output Coupling
Coefficients
K23
BWe
K12, K23, K34
K23
K23
Standard Coupling
Techniques
Input
Output
New Teledyne Coupling
Techniques
BWe
FLow
Frequency
BWe
FHigh
Figure 1. Teledyne loop technology reduces coupling
coefficient variations
tion filters hold the line on selectivity
without forcing a change in architecture
to higher intermediate frequencies or to
new conversion schemes. Wide bandwidth
filter specifications may be found on pages
122.
Balanced Magnet Structure
Tuning a ferrimagnetic resonator over a
large frequency range in the microwave
region requires high magnetic fields.
Over 6,400 Gauss are required to bias a
YIG sphere to 18 GHz. This field must
be uniform in the region of the sphere. In
the absence of magnet saturation, a linear
current in the coils of the electromagnet
produces a linear field in the magnet gap.
However, as Figure 2 shows, leakage flux
(flux that does not bias the sphere) will
cause tuning non-linearity. This leakage
flux is considerably more pronounced with
“single ended” magnets than with the
Teledyne “balanced” structure. Teledyne’s
balanced magnet need not be increased
in size to compensate for the leakage
flux. Thus, for the same magnet volume,
Ferretec can offer more linear tuning than
devices employing single-ended magnets.
OFOISR App 06-S-1942
Moisture-sealed magnet structures for
MIL environments without using paint or
epoxy.
Temperature Compensated Magnet
By compensating the magnetic field zero
frequency drift is possible.
Ferrimagnetic spherical resonators, properly positioned in the magnetic field, are
extremely well behaved over a wide temperature range. Positioned on a particular
axis, and temperature controlled by small
heater elements, most materials experience almost no drift.
Since Teledyne filters contain no exposed
active semi-conductors, they are basically
passive components which need not be
hermetically sealed. However, for most
defense electronics applications, it is obviously necessary to prevent moisture, dust,
and salt atmosphere from entering the
magnet and eventually causing corrosion
which would lead to premature failure.
Many manufacturers have resorted to epoxy and/or RTV potting and epoxy paints
Stabilizing the magnetic structure, however, represents a much greater challenge.
Gap changes as small as 3 millionths of
an inch (.076 microns) at 18 GHz cause
a 1 MHz shift in filter frequency.
Uncompensated, a filter in a nickeliron electromagnet will drift +11
MHz as the temperature is varied
from -55 to +85°C, the MIL-E5400, Class 11 temperature range.
Ferretec magnets are temperaturecompensated using uniquely shaped
rings of a different metal both to
BALANCED
UNBALANCED
compensate for the air gap changes
in the magnet and to track the several
Figure 2. Reduced leakage flux in balanced magnets
resonators across the tuning range.
improve leakage
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Technology Features
to accomplish this sealing. However,
these methods do not stand up under the
constant temperature cycling and vibration experienced over an extended period
of time.
Teledyne magnets are sealed without
paint or epoxy. As Figure 3 shows,
fluorosilicon O-rings are used to seal the
unique three-piece magnet. These devices
are guaranteed to maintain the seal for
the lifetime of the filter. This gives the
reliability engineer the confidence that a
unit will not only pass the qualification
O-Ring Seals
Connector Assembly
O-Ring Seals
Magnet Cup
to within .01% at a level of 900 mA. A
driver, or voltage-to-current converter,
must therefore have the capability to
translate a specific voltage input to the
required current, with high accuracy, over
the life of the system.
Changes in the values of resistors,
integrated circuits, and potentiometers
over time degrade filter tuning accuracy.
Teledyne has analyzed these aging effects
in YIG filter drivers and has developed
a highly stable circuit which minimizes
aging. This requires the use of high-quality devices such as stable
IC voltage references and
low-drift operational
amplifiers. In addition,
this necessitates the use
of a minimum adjustment
O-Ring Seals
range on the slope and
YIG Access Hole
offset potentiometers, and,
in some cases, no potentiometers at all.
Figure 3. Teledyne Magnet structure is moisture sealed
with lifetime guarantee O-rings
Ultra-stable driver
Stabilized driver circuits with the best
available components for enhanced tuning
accuracy over the life of the unit.
Given that typical filter bandwidths are
often less than 0.1% suggests that setting
them properly on frequency requires superior control of the magnet coil current.
For example, if the tuning sensitivity of
the magnet is 20 MHz/mA, setting the
frequency to within 2 MHz at 18 GHz
requires that the current be accurately set
OFOISR App 06-S-1942
For MIL applications, all
parts are selected from
established reliability
components or screened to
equivalent requirements.
More information on tuning errors in YIG filters
is available in a comprehensive technical note (see
page 38). Driver specifications can be found on
page 24.
Closed-Loop YIG Filters
Closed-loop filters contain a patented
locking circuit insuring unmatched
tuning accuracy and repeatability in the
harshest environments.
Regardless of the care taken in the design
and manufacture of YIG filters, they are
subject to tuning errors that cannot be
predicted or controlled with open-loop
correction schemes. Closed-loop filters
receive a sample of RF power and use
it to sense tuning errors, locking the
filter to the RF sample. For example, a
closed-loop preselector can be locked to a
receiver local oscillator and offset by the
IF frequency, insuring tracking under all
conditions. A closed-loop filter can track a
sweep oscillator or synthesizer to remove
unwanted spurious and harmonic signals.
A notch can be accurately positioned on
an interfering signal to prevent it from
blocking an EW receiver. For more information on closed-loop filters, see pages
9-18.
Filter Capabilities
Tuning Range
YIG devices offer tremendous flexibility
in the choice of tuning range. Since the
coupling coefficients in these inductivelycoupled filters vary with frequency, the
factors limiting tuning range are based
on trade-offs involving input match,
bandwidth growth, spurious responses,
insertion loss, etc.
Bandpass filters can be made to tune
ranges as broad as 20:1 with few compromises in performance and even larger
ratios with trade-offs depending on actual
frequency.
Band-reject filters have a more narrow
notch tuning range due to the inherent
property of transmission line-type characteristics from only a few hundred MHz
to over a 5:1 range. The passbands of
these filters, however, can be made much
broader, covering ranges similar to that of
bandpass filters.
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Filter Capabilities
525
MAX - ULTRA WIDE BANDWIDTH
500
3dB BANDWIDTH (MHz)
475
450
425
200
175
150
MAX - OCTAVE
TUNING
125
MAX - MULTI
+/- OCTAVE TUNING
100
75
50
MIN
25
0.5
1.0
2.0
4.0
6.0
8.0
10.0
20.0
40.0
FREQUENCY - AT LOW END OF TUNING RANGE (GHz)
Figure 4. Range of 3dB bandwidths available in Teledyne bandpass YIG Filters
Instantaneous Bandwidth
Figure 4 shows the wide range of bandwidths Ferretec provides in bandpass
filters. Both minimum and maximum
achievable bandwidths are shown as a
function of the minimum operating frequency of the filter.
tuning range. Ferretec’s precisely designed
structures and proprietary loop configurations minimize this growth while
maintaining the best possible VSWR.
Changes in the coupling coefficients occur
with frequency, and result in the growth
of the bandwidth near the high end of the
OFOISR App 06-S-1942
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Filter Capabilities
Screening Levels
Selectivity
Ratio of Bandwidth to 3dB Bandwidth
Filter selectivity depends on the number
of YIG resonators (stages) in the filter and
60
40
30
20
2-STAGE
region of the filter. Spurious responses
which hold their relative position with
respect to the desired filter response are
termed “tracking modes” Those which
tune at a different rate than
the desired response, and
therefore, at some frequencies cross through the filter
response, are termed “crossing modes”
4-STAGE
Part of the art of the YIG
filter construction consists
of limiting the size of these
7-STAGE
spurious responses, and in
2
controlling their position
1
so as to keep them from
0
10
20 30
40
50 60 70 80
90
appearing, for example, in
Attenuation (dB)
bandpass preselectors just
where local oscillator or
Figure 5. Filter Selectivity
image rejection is desired.
The tracking spurious
is nominally 6 dB per stage per octave
response most often seen in band-pass
bandwidth. Thus, for a four-stage filter,
filters is known as the “210 mode.” It is
the rejection increases by 24 dB each time
greatly suppressed by Teledyne’s proprithe band-width doubles (see Figure 5).
etary coupling loop technology but, in
The number of stages that can be built in
most cases, is somewhat less than the
a single filter is limited by the space under
full off-resonance rejection of the filter.
the magnet pole tips and the need to posiThe location of this mode with respect
tion the spheres for optimum coupling.
to the passband depends mainly on the
Making the pole tips larger increases
saturation magnetization of the ferrituning coil inductance and slows magnet
magnetic resonator. For pure YIG (used
tuning speed. Bandpass filters are usually
in filters operating over 4 GHz), the 210
2 to 7 stages and band-reject filters can be
mode is 600 to 700 MHz below the filter
as many as 16 stages. The ultimate isolaresponse. For example, Gallium-doped
tion of a particular filter also depends on
YIG, used in filters with start frequencies
the number of stages.
of 2 GHz, have a 210 mode approximately
310 to 335 MHz below the filter response.
Spurious Responses
In addition to the 210 mode, band-reject
Spurious responses originate from “magfilters also demonstrate the 540 and 220
netostatic modes” wherein the precession
modes. These are tracking spurious modes
of the electron spins in the ferrimagnetic
which cause narrow notches in the filter
material varies across the sphere, instead
passband, typically 4 dB deep. These
of being uniform as desired. These result
are located above the main filter notch
in secondary resonances which may or
response by 75 to 350 MHz, depending
may not be fixed in position with respect
on the ferrimagnetic material used for the
to the main resonance. They will appear
resonators.
either as ripples in the passband, or as
isolated “bumps” in the off-resonance
10
5
4
3
OFOISR App 06-S-1942
6-STAGE
The following defines the component
quality, inspection, and screening levels
available with Teledyne filters or filters
with drivers. Teledyne Microwave’s quality system is registered to ISO-9001:2004.
Commercial (“C’ )
1. Temperature cycling of filters from
-55°C to +95°C, non-operating, five
cycles.
2. 100% Electrical Test at +25°C:
Tuning Range, Linearity, Bandwidth,
Insertion Loss, Spurious & Ripple,
VSWR, ORI & ORSR F, Limiting
Hysteresis, Tuning Sensitivity,
Heater Current, Bias Current (for
Filter with Driver)
3. 100% External Visual Inspection
4. Operating temperature: 0°C to +60°C
Military (“M”)
1. Temperature cycling of filters from
-55°C to +95°C, non-operating, five
cycles per MIL-STD-202, Method
107D, condition A, except high
temp. shall be +95°C.
2. 100% Electrical Test at +25°C:
Tuning Range, Linearity, Bandwidth,
Insertion Loss, Spurious & Ripple,
VSWR, ORI & ORSR F, Limiting
Hysteresis, Tuning Sensitivity,
Heater Current, Bias Current (for
Filter with Driver)
3. 100% External Visual Inspection
4. Operating temperature: -54°C to
+85°C
5. Filters are “O-ring” sealed
6. Printed circuit board assemblies
are conformally coated to MIL-I46058C.
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Closed-Loop Bandpass Filters
to the “RF” reference, and a frequency
tuning repeatability of ±0.5 MHz.
Teledyne’s closed-loop YIG filter technology has the advantages of precise
frequency tuning, exact frequency repeatability and is self-contained, requiring no
external system correction hardware or
software.
Closed-Loop Filter Product Line
The closed-loop filter corrects all YIG filter tuning errors, regardless
of their origin, and does so in a self-contained package requiring only
a coarse tuning signal and an “RF” reference.
Introduction
YIG filters have many inherent advantages such as wideband tuning, excellent
linearity and low insertion loss. However,
they also have static and dynamic tuning errors that can adversely affect their
microwave system and measurement
performance. These errors include hysteresis, non-linearity, frequency drift over
temperature, and aging of the components
in the YIG driver circuitry. Regardless of
the specific source, these tuning errors all
produce the same net result: A decrease in
the filters’ tuning accuracy and frequency
repeatability.
While YIG filters have extremely good
frequency linearity characteristics (less
than ±20 MHz non-linearity over a 2 to
26.5 GHz tuning range, typically), when
adding up other tuning errors such as hysteresis (10 to 20 MHz) and temperature
drift (10 to 20 MHz), the total frequency
error can become significant. For certain
OFOISR App 06-S-1942
applications these tuning errors can be
tolerated. In others, the tuning errors
are corrected via software algorithms or
computer-controlled correction schemes.
However, the system complexity and
increased processor demands of these
additional correction schemes can make
them a less desirable solution.
In contrast, the closed-loop filter corrects
all YIG filter tuning errors, regardless
of their origin, and does so in a self-contained package requiring only a coarse
tuning signal and an “RF” reference. The
closed-loop filter effectively consists of a
YIG-tuned filter, a frequency discriminator and a driver circuit to tune the filter’s
center frequency. The output of the
discriminator is an error signal that is fed
back to the tuning coil driver, to provide
the required correction of the filter’s
center frequency. The net result is a YIGtuned filter with a guaranteed frequency
accuracy on the order of ±1 MHz relative
For the past 20 years, Ferretec has provided a closed-loop solution in the form
of the analog-tuned Ferretrac® filter. This
unit has found wide-spread usage in both
commercial and military systems, as part
of a closed-loop subsystem, or on a standalone basis. On a single military program
alone, over 1800 Ferretrac® filters were
delivered and installed in the ALQ-172
ECM system.
Recently, Teledyne completed a technology advancement program which resulted
in the development of a digital closedloop filter product line. This unit enjoys
the enhanced performance of closed-loop
technology in a smaller, lighter package that is digitally tuned. Together, the
Ferretrac® and the digital closed-loop
filter are the key components of Teledyne’s
closed-loop product line.
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Closed-Loop Bandpass Filters
Filter Technology
Eliminates System Compromise
When considering open-loop YIG tuned
filters, the designer must often compromise system performance due to tradeoffs in filter performance. Tuning errors
inherent in the YIG device often require
that the filter bandwidth be increased in
an attempt to keep a minimum acceptable
bandwidth on frequency, under all conditions. This necessitates compromises in
system performance parameters, such as
selectivity, image rejection, and passband
ripple. Aging of the components may also
require the end user to employ frequent
and expensive field alignments, or to
develop special calibration algorithms to
maintain these filters on frequency.
Teledyne’s closed-loop filters contain a
unique reference loop circuit that allows a
tunable filter to be locked to an RF reference signal (i.e., a tracking filter) or offset
from the reference signal (i.e., an offset
filter). All tuning errors are corrected by
the loop gain. As a result, the designer
can concentrate on specifying the optimum RF performance required for his
design.
System Solutions
Closed-loop filters offer the system designer a complete solution to the electronically-tunable filter requirement.
The microwave filter, driver circuit (voltage-to-current converter) for main filter
tuning, and the closed-loop circuits are
all contained in one compact assembly.
A closed-loop filter needs only to be installed and supplied with an RF reference
signal and a tuning signal in order to immediately work to specification. No need
to “tweak” drivers, program PROMs, or
make readjustments in the field due to
component aging.
OFOISR App 06-S-1942
Teledyne manufactures companion test equipment
products utilizing closed-loop YIG filter
technology. The C1001 Controller provides all
operating controls and power supplies for the
closed-loop Ferretrac® filter.
Closed-loop filters are always on frequency. No specifications are necessary for
hysteresis, tuning non-linearity, temperature drift, or post-tuning drift. They also
lock onto the reference signal in a fraction
of the time it takes open-loop filters to
settle into the desired band-width. A
“lock” indicator signal provides ongoing
feedback that the filter is locked to the
reference signal.
Teledyne has designed and specified
closed-loop filters to address system and
component requirements. The RF specifications use classical filter parameters such
as those traditionally used for fixed-tuned
filters but defined for tunable system use.
For example, RF bandwidth is specified
relative to the desired center frequency
and rejection is specified at the image
frequency and other pertinent spurious
susceptible frequencies.
Applications
Closed-loop filter applications include
active and passive countermeasures systems, radar and communications systems,
and automatic test instrumentation for
bench and field testing. Some of these
applications are detailed in this catalog.
More extensive closed-loop applications
information can be found in the following
papers available from Ferretec:
1. Application Note FT3, “Improving
Microwave Measurements with
Ferretrac Filters”
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Closed-Loop Filter Operation
The key to closed-loop filter operation
is an additional YIG sphere located in
the same magnetic structure as the filter.
Thus, any variations in the magnetic field,
which tend to tune the filter to other than
the desired frequency are also sensed by
this additional reference sphere. The reference sphere is surrounded by a small air
coil which can be biased to establish any
desired fixed offset, up to ±300 MHz, between the reference sphere and the filter.
Together with the elements of the loop
circuits, the reference sphere and air coil
form a unique microwave discriminator.
Courtesy of USAF
The output of this discriminator is a voltage proportional to the error between the
quiescent tuned frequency of the YIG
filter and the RF reference frequency (+
or - any deliberate offset). This error is fed
back to the main electromagnet driver to
force the filter onto the reference frequency and keep it there under all static and
dynamic conditions (e.g., temperature,
vibration, driver component aging, etc.).
Closed-loop filter applications include active and passive countermeasures systems, radar and communications systems, and automatic test instrumentation
2. Application Note “YIG Preselectors
in Multi-Channel Phase Tracked
Receivers”
3. Application Note “Reference
Stabilized YIG-Tuned Receiver
Front-Ends”
4. Application Note “Ferretrac
Operation”
5. Application Note “Set-on Techniques
for YIG-Tuned Band-Reject Filters”
6. Technical Paper “Digital ASIC
Advances Microwave Filter
Technology”
OFOISR App 06-S-1942
MIL Specification Devices
Teledyne offers closed-loop filters for both
commercial and military applications. For
MIL-SPEC units, Teledyne has carefully selected all passive components from
available established reliability devices.
All semiconductor devices are JANTX or
MIL-STD-883 screened. To ensure the
specified filter performance for MIL environments over the lifetime of the device,
Teledyne has carefully prepared an error
budget using the guaranteed specifications
of these MIL parts.
Figure 6 shows the block diagram of the
basic Ferretrac® device. Note that the
closed-loop circuits are independent of
the filter, allowing complete flexibility for
design and optimization of the filter.
A high loop gain insures a reduction of all
open-loop errors by approximately 200:1.
The discriminator band-width is varied to
initially provide a capture range of ±100
MHz and then reduced to provide better
than 1 MHz resolution. Once within the
capture range of the loop, the filter settles
very rapidly to the specified reference
frequency. A lock indicator, TTL signal
compatible, provides an indication to the
system that the loop has acquired the
referenced signal.
In certain applications, particularly those
involving Doppler signal processing or
synthesizer filtering, it may be necessary
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Closed-Loop Bandpass Filters
Summary of Key Ferretrac®
to disable the closed-loop to eliminate a
small amount of incidental modulation
that is coupled to the main filter from the
reference-sphere air coil. This incidental tuning typically produces amplitude
modulation of 0.5 dB and phase modulation of 2 degrees at a fixed rate of about
350 KHz for the Ferretrac® filter.
Closed-Loop Filters
The specifications presented in this
catalog use super-heterodyne receiver
terminology since a majority of applications are for preselectors or tracking
filters. The closed-loop filter is locked to
a local oscillator or other reference source
frequency, or offset by an intermediate
frequency (IF) from the source frequency.
Care should be taken to avoid confusion
with RF specifications for open-loop tunable filters.
This modulation can be entirely eliminated by employing a sample-and-hold
circuit contained in all closed-loop filters.
After receiving a lock signal indication
that the filter is on frequency, activation of
the “hold” input stores the corrected tuning voltage during the user’s measurement
or signal receiving period. During this
time, for at least one minute (one second
for MIL units at +85°C), the RF bandwidth remains on frequency. Filter tuning
can be periodically updated by returning
to the “sample” mode for approximately
two milliseconds.
FT (Tuned Frequency)
The desired center frequency of the
passband. FT is equal to F0, the reference source frequency + or - the IF offset
frequency.
FO (Reference Frequency)
The reference source (or local oscillator)
frequency. For zero offset (tracking filter)
FO=FT.
Common Magnet
RF Input
YIG Filter
RF Reference Circuits
Hold
Control
Loop Circuit
Error Signal
FI (Image Frequency)
RF
Output
Reference
Input
Lock
Indicator
Driver
Circuit
Filter
Coarse Tune
Figure 6. Ferretrac® Functional Block Diagram
OFOISR App 06-S-1942
The image frequency in a receiver located
on the opposite side of the local oscillator,
FO, and spaced from FO by the IF offset.
BW (3 dB Bandwidth)
The minimum frequency band centered
on the desired tuned frequency, FT, over
which the total filter loss will not exceed
IL + IR.
IL (Insertion Loss)
The insertion loss at a point in the bandwidth BW that exhibits the minimum
value.
IR (Passband Ripple)
The maximum ripple, including magnetostatic modes occurring in the bandwidth
BW.
1274 Terra Bella Avenue, Mountain View, CA 94043
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VSWR
RF (Half IF Rejection)
Measured at the best point in the bandwidth BW.
IF (Intermediate Frequency)
The offset frequency (+ or -) at which the
bandwidth BW is centered from the reference frequency FO.
RI (IMAGE REJECTION)
The minimum rejection in a band BW
wide centered at a frequency FI on the
opposite side of FO from the passband
(usually called the “image band”). In the
case of zero offset (filter tracks on reference frequency) RI is defined as the minimum rejection ±200 MHz from FT.
The minimum rejection, in a band BW/2
wide centered at one-half of the IF
frequency from the tuned frequency FT
and located between FT and FO. This
“half IF” rejection is needed to determine
rejection of a spurious intermodulation
product in the receiver systems caused by
2L0, 2SIG combinations.
RC (LO REJECTION)
The minimum rejection at the reference
frequency, FO. This is needed to determine the amount of “LO suppression”
provided by the filter in receiver applications.
RH (HARMONIC REJECTION)
The minimum rejection at harmonics and
subharmonics of the frequency FT within
the specified tuning range.
IR
IL
0 dB
RF
RH
RC
RI
BW
IF/2
IF
IF
FT/N
FI
FO
FT
N x FT
Figure 7. Closed-loop bandpass filter specification definitions
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Ferretrac® Model Number System
FT
Always “1” for
Catalog Model 1
OFFSET
X
0
1
2
3
4
5
7
1
2
2
MHz
-160
+160
-60
+60
-300
+300
0
X
0
1
2
3
4
5
6
7
1
NO. STAGES &
COARSE TUNE VOLTAGE
Stages
Tuning Voltage
2
0.0 to 10.0 V
4
0.0 to 10.0 V
2
1.0 V/GHz
4
1.0 V/GHz
2
0.5 V/GHz
4
0.5 V/GHz
2
0.25 V/GHz
4
0.25 V/GHz
X
X
X
M
TUNING RANGE
X
1
2
3
4
5
6
7
9
COMPONENT SCREENING LEVEL
GHz
0.5 to 2.0
2.0 to 8.0
6.0 to 18.0
8.0 to 18.0
2.0 to 18.0
18.0 to 26.5
20.0 to 40.0
2.0 to 26.5
C
COMMERCIAL
M
MIL
Specials are assigned model numbers which are of the form FT2XXX. The last three digits are assigned sequentially.
Any offset between ±300 MHz are available on special order.
PARAMETER
Tuning Range (GHz)
Offset (MHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
RF (Half IF) (dB, min)
RC (Reference) (dB, min)
RI (Image) (dB, min)
RH (dB, min)
Course Tune Voltage
FT1101
0.5 to 2.0
+160
10
4.0
1.5
25
35
40
40
0 to 10 V
2-STAGE
FT1425
2.0 to 18.0
-300
15
4.0
1.5
20
35
40
40
1.0 V/GHz
FT1046
18.0 to 26.5
-160
20
4.0
2.0
12
25
35
40
0.5 V/GHz
FT1111
0.5 to 2.0
+160
10
7.0
1.5
50
70
70
70
0 to 10 V
4-STAGE
FT1435
FT1056
2.0 to 18.0
18.0 to 26.5
-300
-160
15
20
6.0
6.0
1.5
2.0
70
25
70
50
70
70
80
70
1.0 V/GHz
0.5 V/GHz
FT1117
20.0 to 40.0
+160
15.0
8.0
2.0
15
40
60
60
0 to 10 V
4-STAGE
FT2510 1
FT1759
2.0 to 20.0 2.0 to 26.5
15.0
15.0
7.0
8.0
80.0
70.0
0.5 V/GHz
0.5 V/GHz
FT1777
20.0 to 40.0
15.0
8.0
60.0
0.25 V/GHz
Tracking (Zero Offset) Filters *
PARAMETER
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
RH (dB, min)
Course Tune Voltage
FT1741
0.5 to 2.0
15.0
4.0
40.0
0.5 V/GHz
2-STAGE
FT2500 1
FT1749
2.0 to 20.0 2.0 to 26.5
15.0
15.0
4.0
5.0
40.0
40.0
0.5 V/GHz
0.5 V/GHz
FT1767
20.0 to 40.0
15.0
5.0
30.0
0.25 V/GHz
FT1751
0.5 to 2.0
15.0
7.0
70.0
0.5 V/GHz
* Fully compatible with C1001 Controller
1 Special Numbers Assigned
Consult factory for availability of other tuning ranges and tuning voltages.
All Specifications shown are for operating temperatures of 0 to 60°C for commercial units and -55 to +85°C for MIL-SPEC units.
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Ferretrac® Bandpass Filter Specifications
Offset Filters - 2-Stages
2-Stages
Tuning Range (GHz)
BW (MHz min)
IL (dB max)
IR (dB max)
Rejection (dB min)
60 MHz Offset
(X = 2 or 3)
160 MHz Offset
(X= 0 or 1)
300 MHz Offset
(X = 4 or 5)
All Offsets
FT1X01
0.5 to 2.0
10.0
4.0
1.5
FT1X02
2.0 to 8.0
20.0
3.0
1.5
Fri X03
6.0 to 18.0
20.0
3.0
1.5
FT1X04
8.0 to 18.0
20.0
3.0
1.5
FT1X05
2.0 to 18.0
15.0
4.0
1.5
FT1X06
18.0 to 26.5
20.0
4.0
2.0
FT1X07
20.0 to 40
15.0
5.0
2.0
RF
RC
RI
20
30
15
25
10
20
10
20
6
20
6
20
-
RF
RC
RI
25
35
40
20
30
40
15
25
35
15
25
35
12
25
35
12
25
35
12
25
35
RF
RC
RI
RH
35
40
40
40
30
40
45
45
25
35
45
45
25
35
45
45
20
35
40
40
20
35
40
40
20
35
40
35
FT1X11
0.5 to 2.0
10.0
7.0
1.5
FT1X12
2.0 to 8.0
20.0
5.0
1.5
FT1X13
6.0 to 18.0
20.0
4.5
1.5
FT1X14
8.0 to 18.0
20.0
4.5
1.5
FT1X15
2.0 to 18.0
15.0
6.0
1.5
FT1X16
18.0 to 26.5
20.0
6.0
2.0
FT1X17
20.0 to 40.
15.0
8.0
2.0
RF
RC
RI
40
60
30
50
20
40
20
40
12
40
12
40
-
RF
RC
RI
50
70
70
40
60
70
30
50
70
30
50
70
25
50
70
25
50
70
15
40
60
RF
RC
RI
RH
70
70
70
70
70
70
70
80
70
70
70
80
70
70
70
80
70
70
70
80
70
70
70
70
60
60
60
60
Offset Filters - 4-Stages
4-Stages
Tuning Range (GHz)
BW (MHz min)
IL (dB max)
IR (dB max)
Rejection (dB min)
60 MHz Offset
(X= 2 or 3)
160 MHz Offset
(X = 0 or 1)
300 MHz Offset
(X = 4 or 5)
All Offsets
The above units have 0 to 10 volts coarse tuning; for other coarse tuning voltages available see Model Number System.
All specifications shown are for operating temperatures of 0 to 60°C for commercial units and -55 to +85°C for MIL-SPEC units.
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Teledyne has introduced a line of digitally
tuned closed-loop bandpass filters based
on Ferretrac® technology. Similar RF
performance to the Ferretrac® is available
in a smaller and lighter package. Loop
and control circuits are realized digitally,
allowing for a “zero droop” sample-andhold, and the elimination of all potentiometers. Programmable logic arrays allow
for frequency calibration and provide for
system design flexibility
Features:
♦♦
12 Bit Digital (TTL) Tuning Control
♦♦
Zero Droop Sample-and-Hold
♦♦
Reduced Size and Weight
♦♦
No Potentiometers
Typical RF Specifications
2-Stage Closed-Loop Bandpass Filters with +160 MHz Offsets [1]
2-Stages
Tuning Range (GHz)
BW (MHz min)
IL (dB max)
IR (dB max)
RH (Harmonic Rej. dB min)
Rejection with +160 MHz
Offset (dB min)
RF (Half IF)
RC (Reference)
RI (Image)
1.
2.
3.
FTD1101
0.5 to 2.0
10.0
4.5
1.5
FTD1102
2.0 to 8.0
20.0
3.5
1.5
FTD1103
6.0 to 18.0
20.0
3.5
1.5
FTD1104
8.0 to 18.0
20.0
3.5
1.5
FTD1105
2.0 to 18.0
15.0
4.5
1.5
40
45
45
45
40
25
35
40
20
30
40
15
25
35
15
25
35
12
25
35
12-Bit Digital Tuning Word Input: Low-end frequency corresponds to all zeros, high-end frequency corresponds to all ones.
Consult factory for availability of other tuning ranges.
All specifications shown are guaranteed for operating temperatures of 0 to 60°C for commercial units and -55 to +85°C for MIL-SPEC units
4-Stage Closed-Loop Bandpass Filters with +160 MHz Offsets [1]
4-Stages
Tuning Range (GHz)
BW (MHz min)
IL (dB max)
IR (dB max)
RH (Harmonic Rej. dB min)
Rejection with +160 MHz
Offset (dB min)
RF (Half IF)
RC (Reference)
RI (Image)
1.
2.
3.
FTD1111
0.5 to 2.0
10.0
8.0
1.5
FTD1112
2.0 to 8.0
20.0
6.0
1.5
FTD1113
6.0 to 18.0
20.0
5.5
1.5
FTD1114
8.0 to 18.0
20.0
5.5
1.5
FTD1115
2.0 to 18.0
15.0
7.0
1.5
70
80
80
80
80
50
70
70
40
60
70
30
50
70
30
50
70
25
50
70
12-Bit Digital Tuning Word Input: Low-end frequency corresponds to all zeros, high-end frequency corresponds to all ones.
Consult factory for availability of other tuning ranges.
All specifications shown are guaranteed for operating temperatures of 0 to 60°C for commercial units and -55 to +85°C for MIL-SPEC units
[1] Other offsets between ±300 MHz are also available.
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Digital Closed-Loop Bandpass Filter Specifications
Tracking Closed-Loop Bandpass Filters (Zero Offset)
2-Stages
FTD1741
0.5 to 2.0
15.0
4.5
40
Tuning Range (GHz)
BW (MHz min)
IL (dB max)
RH (dB min)
FTD1751
0.5 to 2.0
15.0
8.0
70
FTD2510
2.0 to 20.0
15.0
8.0
80
12-Bit Digital Tuning Word Input: Low-end frequency corresponds to all zeros, high-end frequency corresponds to all ones.
Consult factory for availability of other tuning ranges.
All specifications shown are guaranteed for operating temperatures of 0 to 60°C for commercial units and -55 to +85°C for MIL-SPEC units
Filter Repeatability: ±0.5 MHz Max
Accuracy: Filter center frequency accuracy
is ±1 MHz of reference signal typically.
The major contributors to short-term
repeatability errors in conventional
YIG devices are Magnetic Relaxation
Uncertainty (MRU) and Post Tuning
Drift (PTD). MRU is related to what is
commonly referred to as “hysteresis” in
the magnet. It is an unstable magnet bias
condition that changes dramatically as
a function of tuning step size, vibration,
and shock. The result is a fixed-frequency
uncertainty with a potential spread equal
to the magnet “hysteresis”
VSWR: 2.0:1 (Best Point)
Tuning Speed: Tuning speed is the time
from the initiation of a tuning step to the
presence of the desired bandwidth (BW)
centered at the desired frequency (FT).
Step Size (GHz) 1
Tuning Time
(msec max)
Both MRU and
PTD are present,
even at a fixed ambient temperature. In
Ferretrac® filters both
errors are reduced
by the loop gain,
providing a dramatic
improvement in
repeatability as illustrated in Figure 8.
OFOISR App 06-S-1942
REPEATABILITY (MHz)
PTD is caused by the thermal gradient set
up in the magnet shell due to the uneven
internal heating by
the tuning coil. The
dissipation typically
+20
varies from 50 mW
+15
to 5 Watts from 2 to
+10
18 GHz.
1
2
4
8
12
16
2
3
5
8
10
YIG filter tuning speed curves show a
long time constant “tail” as shown in
Figure 9. Ferretrac® filters overcome this
effect since, after acquisition by the loop,
the filter tuning error AF is reduced to
zero with a loop time constant of approximately 100 microseconds.
30
25
ΔF (MHz)
1.
2.
3.
4-Stages
FTD2500
2.0 to 20.0
15.0
4.5
40
OPEN LOOP
CLOSED LOOP
20
16GHz STEP
8GHz STEP
15
1GHz STEP
10
5
FT
5
10
15
20
25
30
Time mS
+5
FERRETRAC
+/- 0.5 MHz
FT
-5
Figure 9 Tuning speed enhanced by closed-loop
circuit
-10
-15
OPEN LOOP
-20
2
4
6
8 10 12 14 16 18
TUNING STEP (GHz)
Figure 8 Repeatability as a function of Tuning Step (GHz)
shows the effects of Magnetic Relaxation Uncertainty (MRU)
and Post Tuning Drift (PTD).
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
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Digital Closed-Loop Bandpass Filter Specifications
Heater Current2-Stage4-Stage
Filter Input Signal (unless otherwise specified)
Start Frequencies: Below 1 GHz 1 dB Compression (min)
Above 1 GHz
Surge (max)
0.75 A
1.2 A
+10 dBm
+25°C Steady State
75 mA
125 mA
-55°C Steady State 150 mA
250 mA
0 dBm
No Damage (max)
1 Watt CW
Frequency Reference
RF Power Input
Ferretrac®:
-15 dBm min/-5 dBm max
No Damage (max)
1 Watt CW
Source VSWR Required
1.5:1 max
Reference Accuracy
The frequency of the signal fed to the reference port must be
within ±50 MHz of the frequency indicated by the tuning voltage. (Typical accuracy is ±1 MHz relative to reference frequency.)
Reference Offset: up to ±300 MHz
+15 VDC ±10% at 1 mA per MHz of offset plus 100 mA for
zero or negative offset, or, plus 200 mA for positive offset.
-15 VDC ±10% at 60 mA, plus typically 50 mA times max
frequency in GHz.
Outline Drawings:
See Ferretrac® Outline Drawing 0200001 Rev. 6 on page 35.
See Digital Closed-Loop Outline Drawing 0200182 Rev. 1 on
page 35.
Lock Indicator
Standard TTL output, 2 loads Digital “0” 0.4 ± .4 VDC Digital
“1” 3.5 ± 1.5 VDC
Logic “0” indicates in capture range
Logic “1” indicates outside capture range, 3.5 ± 1.5 VDC
Sample and Hold:
Standard TTL Input Logic Digital “0” 0.4 ± 0.4 VDC Digital
“1” 3.5 ± 1.5 VDC
“0” Commands Hold
“1” Commands Closed Loop
Ferretrac® Tuning Input:
Input Voltage to Tune Full Band:
0 to 10 VDC, 1 V/GHz, 0.5 V/GHz and 0.25 V/GHz are
available. For offset filters, reference tracking is also available
(coarse-tune voltage tracks reference frequency rather than filter
frequency).
Input Impedance: minimum 10K ohms
Digital Closed-Loop Tuning Input:
12-Bit digital tuning word. Low-end frequency corresponds to
all zeros, high-end frequency corresponds to all ones.
Power Requirements 28 ± 4 VDC (heaters)
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Closed-Loop Bandpass Filter Applications
Receiver Preselection
Teledyne closed-loop filters are ideal for
receiver preselector applications where
suppression of spurious responses is the
key to system performance.
Figure 10 shows the block diagram of
a receiver front end using a closed-loop
preselector. A sample of the local oscillator signal is coupled to the closed-loop
reference input and the filter locks onto
the local oscillator, offset precisely by the
IF frequency. This ensures that the minimum loss bandwidth of the filter is always
centered on the desired frequency. The
filter response can then be optimized for
in band and skirt response characteristics
without any compromises due to poor oscillator tracking, non-linearities, temperature drift, or other open-loop errors.
causing sizable measurement
errors unless adequate filtering
of the signal source output is
provided. Also, automatic test
systems, operating over wide
dynamic ranges, are easily confused in the presence of multiple, simultaneous outputs.
1 OR 1/2 GHz/VOLT
OUTPUT
SWEEPER
OR SYNTHESIZER
RF
Figure 11 shows a closed-loop
COUPLER
RF
filter used to “clean-up” a
OUTPUT
sweep oscillator or synthesizer.
The voltage reference output
RF
CLOSED-LOOP
INPUT
of the sweeper (normally
FILTER
REF INPUT
1.0 or 0.5 V/GHz) is used to
coarsely tune the filter, while a
HOLD
LOCK
CONTROL
INDICATOR
sample of the signal RF output
FILTER
provides an RF reference for
COARSE
the loop circuits. The filter is
TUNE
then automatically centered on
Figure 11 - Closed-Loop Filter in a source “clean-up”
the signal reducing harmonics application
and other spuriRECEIVER
ous outputs of the
RF
MIXER
RF
source to the required level.
INPUT
OUTPUT
Other applications of Teledyne closedIn this application, the filter
IF
REF INPUT
bandwidth can be kept narrow loop filters can be found in the Teledyne
HOLD
CLOSED-LOOP
OUTPUT
Application Note FT3 “Improving
since the tracking is autoCONTROL
FILTER
Microwave Measurements with Ferretrac
matic, and the output power
Filters” available on request.
can
be
kept
well
leveled
even
COUPLER
LOCK
INDICATOR
while sweeping, since there is
no “peaking” needed to keep
FILTER
the signal at the minimum loss
COARSE
OSC TUNE
TUNE
LOCAL
point of the passband. Best of
OSCILLATOR
all, there are no adjustments
needed when changing the
TUNING INPUT
end limits of the frequency
sweep, alternately switching
Figure 10 - Closed-Loop Filter in a receiver preselector
between different frequency
application
end limits, or randomly programming with a computer.
In automatic test equipment, no separate computer controls are required. The
Sweet oscillators and frequency synthesizclosed-loop filter is automatically IEEEers output harmonics and subharmonics
488 Bus compatible since it faithfully
that are unacceptable to the user for many
tracks any programmed signal from the
applications. Scalar network analyzers, for
source.
example, cannot distinguish between fundamental and harmonic signal content,
Other Applications
Source “Clean Up”
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Open-Loop Bandpass Filters
Bandpass Filter Specification
Definitions
Selectivity
Filter selectivity depends on the number of YIG resonators (stages) and is
nominally 6 dB per stage per octave
bandwidth. Thus for a six-stage filter, the
rejection increases by 36 dB each time the
bandwidth doubles (see Figure 5, page 8).
Limiting Level
The input power at which the input/output transfer characteristic exhibits a 1 dB
compression.
Linearity
The maximum deviation of the tuned
center frequency versus coil current from
a best fit straight line over the specified
operating frequency range.
Hysteresis
The maximum value of the differential
tuned frequency, at the same coil current,
when the coil is tuned slowly throughout
OFOISR App 06-S-1942
the operation range in both
directions.
Since this hysteresis is caused
by an unstable magnetization, it represents a tuning
uncertainty as shown in Figure
12. For a given coil current,
the tuned frequency will
fall within the shaded area
depending on tuning step size
and speed, and also environment factors. The line A-B
represents a stable magnetic
condition. This can be best
realized by step tuning each
frequency from the low end of
the tuning range.
Temperature Drift
The change in resonant frequency (at a fixed coil current)
corresponding to a change in
ambient operating temperature. Teledyne filter designs are
mechanically compensated to
reduce this temperature drift.
B
Stable
Tuning Line
Repeatability Error (MHz)
Teledyne YIG Filters have been designed
to meet the multi-octave, wide dynamic range requirements of today’s EW
systems and instruments. The electrical
length of the interstage coupling elements
is kept to a minimum so that multi-octave
performance is achieved with no degradation over previous octave designs. Lowloss, gold plated cavities allow Teledyne
to achieve the superior selectivity and
off-resonance rejection of a 6-stage bandpass filter with the lower insertion loss of
4-stage filters. For military units, rugged
construction in a temperature compensated, moisture sealed magnet maintains
specified performance over the temperature, humidity, and salt-spray environments of MIL-E-5400 Class II.
Hysteresis
A
FLow
FHigh
Figure 12 — Magnetic Relaxation Uncertainty — Maximum
frequency repeatability error at any fixed coil current due to
unknown hysteresis bias of the magnet as a result of tuning
speed, magnitude of step and/or direction, vibration, and
mechanical and/or thermal shock. Maximum error is equal
to hysteresis.
Tuning Speed
There are several factors affecting
tuning speed including tuning
coil and magnet design, method
of tuning, driver design, etc.
The nominal full-band switching speed is 10 milliseconds to
approach within 0.5% of the final
frequency (see page 16). For data
on tuning speed for a particular
application, consult Teledyne
directly.
Teledyne YIG Bandpass filters must function in a dense
electromagnetic signal environment where preselection is
required to separate signals from spurious, to reject co-located
high-level interference, and maximize receiver sensitivity.
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Open-Loop Bandpass Filter Specifications
Model Number System
FXXXX
Basic Model
Number
C
C - Commercial
M - MIL
-
AD
No Suffix - Filter Only
AD - Analog Driver
DD - Digital Driver
Bandpass Filters Specification Definitions
RF Parameters (See Figure 13)
IL (Insertion Loss): The loss at the point in the passband exhibiting
the minimum loss value.
IR
IL
3dB
0 dB
ORS ORI
BW
BW (3 dB Bandwidth): The bandwidth measured where the insertion loss is 3 dB greater than the mini-mum loss value, IL.
(Passband Ripple): The sum of amplitude ripple and spurious re-
sponses which cross through the filter passband. The filter ripple
changes with tuning due to interstage coupling variations and
frequency pulling of the YIG resonators. Spurious responses are
due to magnetostatic modes that are excited in the YIG spheres.
Some track the main filter response at a relatively fixed frequency
offset while others tune at a different rate than the passband and
appear to “walk through” the passband as it is tuned. Additional
losses due to the spurious modes that track at a different rate
than the filter passband are included in IR.
FT
Figure 13 - RF specification definitions for bandpass filters
Return Loss (VSWR): Measured at the best point in the bandwidth,
BW.
ORI (Off-Resonance Isolation): The rejection, referenced to IL, mea-
sured at any frequency outside of the filter passband skirts within
the specified tuning range. It is usually measured by turning the
filter off and observing the residual signal leakage level.
ORS (Off-Resonance Spurious): The amount of suppression referenced to IL of magnetostatic spurious modes that track at a
nearly fixed offset from the main filter response. Since their frequency spacing can be controlled in the design by the choice of
YIG material used, the system designer should specify any offset
frequency range that is required to be free of spurious modes
(i.e., the image frequency, local oscillator frequency, harmonics,
etc.). These modes are typically only a few MHz wide.
OFOISR App 06-S-1942
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Specifications - 2 Stage Filters
Parameter
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
ORI (dB, min)
ORS (dB, min)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temp. Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/mA, nominal)
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
With analog driver
With digital driver
F1051
F1052
F1053
F1054
F1055
F1056
0.5 to 2.0
20
4.0
1.5
45
25
±3
4
2.0 to 8.0
25
3.0
1.5
50
30
±6
10
6.0 to 18.0
25
3.0
1.5
50
30
±10
15
8.0 to 18.0
25
3.0
1.5
50
30
±12
15
2.0 to 18.0
25
4.0
1.5
45
25
±15
20
8.0 to 26.5
40
4.0
2.0
40
30
±20
25
6
10
8
15
15
25
15
25
20
30
25
40
10
20
20
20
20
40
4.5
40
4.5
40
4.5
40
4.5
40
4.5
40
10.0
150
1
2
[1]
1
2
[1]
1
2
[1]
1
2
[1]
1
2
[1]
1
2
[1]
F1071
F1072
F1073
F1075
F1076
F1077
F2000
0.5 to 2.0
20
7.0
1.5
70
50
±3
4
2.0 to 8.0
25
5.0
1.5
80
50
±6
10
6.0 to 18.0
25
4.5
1.5
80
50
±10
15
2.0 to 18.0
25
6.0
1.5
80
40
±15
20
8.0 to 26.5
40
6.0
2.0
60
40
±20
25
8.0 to 26.5
50
7.0
2.0
60
30
±30
60
3.0 to 50.0
30
7.0
2.0
55
30
±35
70
6
10
8
15
15
25
20
30
25
40
40
60
50
70
10
20
20
20
40
28
25
4.5
40
4.5
40
4.5
40
4.5
40
10.0
150
6.0
100
6.0
100
1
2
7
1
2
7
1
2
7
1
2
7
3
6
7
4
[1]
[1]
4
[1]
[1]
Specifications - 4 Stage Filters
Parameter
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
ORI (dB, min)
ORS (dB, min)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temp. Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/mA, nominal)
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
With analog driver
With digital driver
[1] Consult Factory
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
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Open-Loop Bandpass Filter Specifications
Specifications - 7 Stage Filters
Parameter
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
ORI (dB, min)
ORS (dB, min)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temp. Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/mA, nominal
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
With analog driver [1]
With digital driver [1]
OFOISR App 06-S-1942
F1080
F1081
F1082
F1083
F1084
0.5 to 2.0
25
8.0
1.5
80
60
±3
4
2.0 to 8.0
60
6.0
1.5
100
60
±6
10
6.0 to 18.0
90
6.0
1.5
100
60
±20
15
8.0 to 18.0
100
6.0
1.5
100
60
±20
15
2.0 to 18.0
50
7.0
2.0
100
50
±20
20
6
10
8
15
15
25
12
25
20
30
10
20
20
20
20
4.5
40
4.5
40
4.5
40
4.5
40
4.5
40
5
5
5
5
5
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Wide Bandwidth Bandpass Filters
Wide Instantaneous
Bandwidth Filters
Introduction
Today’s surveillance receivers, EW
countermeasure systems, and EMI
measurement instruments require wider
instantaneous bandwidths than the 15 or
20 MHz normally available. The signals
they must process are increasingly more
complex with wider information bandwidth. They also must function in a dense
electromagnetic signal environment where
preselection is required to separate signals
from spurious, to reject co-located high
level interference, and maximize receiver
sensitivity.
Teledyne has developed a series of very
wide instantaneous bandwidth bandpass filters which offer an ideal solution.
Advanced computer aided design has
enabled the incorporation of new coupling
techniques to pro-vide the needed bandwidths while demonstrating low insertion
loss, low passband ripple, and superior
pass-band VSWR. These techniques
also minimize variation in group delay, a
parameter which is becoming even more
important with the increase in complexity
and bandwidth of the signal environment.
The units specified in this catalog show
Teledyne’s capability to produce widebandwidth bandpass filters with limiting
levels in the range 0 dBm to over +10
dBm (rather than the -23 dBm maximum
linear input levels of filters operating
in coincidence limiting). The wideband
filters in this catalog are divided into two
groups: Increased BW filters with bandwidths from 30 to 80 MHz for multi-octave tuning ranges, and wide-band filters
with up to 500 MHz bandwidth in the 6
to 18 GHz range.
OFOISR App 06-S-1942
Design Tradeoffs For 500MHz Filters
To achieve extremely wide bandwidths,
on the order of 500 MHz, high saturation
magnetization Teledyne materials, such
as Nickel Zinc Ferrite or Lithium Ferrite
are required. However, the limiting level
of Nickel Zinc decreases rapidly as the
filter is tuned below 11 GHz. This results
in a 500 MHz BW filter that is not only
limited to a tuning range of approximately
8-18.5 GHz, but also has a decreased
input limiting level (typically +3 dBm). A
third consideration in designing a system
with a 500 MHz wide YIG filter involves
the location of the 210 spurious mode.
Its location can affect the image rejection
specification under certain conditions,
such as in systems with an IF frequency of
1 GHz and a low side LO. For these extremely wideband filters, the 210 spurious
mode frequency is fixed at approximately
2 GHz below the filter passband, which
is also the tuner’s image frequency for a
1 GHz IF Thus, the 210 mode can cause
a decrease in the system image rejection
performance. This situation can be avoided at the system design level via selection
of the IF frequency. For instance, an IF of
750 MHz has an IF image frequency of
1500 MHz which is offset from the 210
spurious mode by 500 MHz, typically.
However, for wideband tuners requiring a
1 GHz IF and an image rejection specification of greater than 70 dB, the task of
building these wideband filters becomes
extremely difficult. Teledyne has developed a wideband filter that addresses this
problem.
7-Stage Wideband Filter Solution
The image rejection is improved in a 1
GHz IF system by the increased ORS
suppression of the 6-stage filter design.
However, achieving a specification of >60
dB ORS suppression at FT-2 GHz while
maintaining a 500 MHz minimum bandwidth has proven extremely difficult to
accomplish on a production basis, even for
a 6-stage design. To provide a filter that
not only meets the wide bandwidth and
increased ORS requirement, and can also
be built on a repeatable basis, Teledyne
has developed an advanced technology
7-stage wide-band filter design.
This “second generation” wideband
filter technology has achieved the three
primary design goals of: 1) Increased
minimum bandwidth specification margin
(550 to 600 MHz, versus 500 MHz), 2)
Increased ORS suppression of 70 dB, for
the worst-case system requirements of
high IF image suppression and 1 GHz IF,
and 3) Achieving these specifications on a
consistent and repeatable basis, to support
large production quantities.
This wide bandwidth filter is ideal for
wideband ELINT receivers. They are primarily used in the 8-18.0 GHz band, but
are also suited for usage over the extended
6-18.0 GHz frequency range, with only
minor performance tradeoffs.
In addition to increasing margin for key
filter specifications such as minimum BW,
off-resonance spurious, and off-resonance
isolation, Teledyne’s advanced technology maintains excellent input and output
VSWR while minimizing passband spurious and ripple. These wideband filters
can be built and aligned in an efficient,
cost-effective manner, resulting in a filter
which can be shipped in large quantities,
with consistent repeatable performance.
The filters are packaged in a 1.7” cube,
and can be supplied with drivers (digital
or analog), if required. For increased spurious suppression and selectivity requirements, additional stages can be accommodated with the current technology.
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Wide Bandwidth Bandpass Filter Specifications
Specifications - 4-Stage Increased Bandwidth Bandpass Filters
Parameter
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
ORI (dB, min)
ORS (dB, min)
Limiting Level (dB, min)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temp. Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/ma, nominal)
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
With analog driver
With digital driver
F1091
0.5 to 2.0
25
6
2
70
40
0
±3
4
F1092
1.0 to 4.0
45
5
2
70
40
0
±4
6
F1093
2.0 to 6.0
70
5
2
70
40
+10
±4
8
F1094
2.0 to 8.0
70
5
2
70
40
+10
±6
10
F1095
2.0 to 18.0
50
6
2
65
40
+10
±15
25
F1096
8.0 to 26.5
80
7
2
70
40
+10
±10
15
10
15
10
12
20
10
12
25
20
15
30
20
25
40
20
25
40
20
4.5
4.5
4.5
4.5
4.5
4.5
40
40
40
40
40
40
1
2
7
1
2
7
1
2
7
1
2
7
3
6
7
3
6
7
Specifications - Ultra-Wide Bandwidth Bandpass Filters
Parameter
F1097
6.0 to 18.0
450
6.0
2.5
60
40
0[1]
±80
15
Tuning Range (GHz)
BW (MHz, min)
IL (dB, max)
IR (dB, max)
ORI (dB, min)
ORS (dB, min)
Limiting Level
Linearity (MHz, max)
Hysteresis (MHz, max)
Temp. Drift (MHz, max)
O to 60°C
15
-55 to +85°C
25
Tuning Sensitivity
20
(MHz, nominal)
4.5
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
40
Outline
Filter
3
With analog driver
6
With digital driver
7
[1] Limiting level increases to greater than +10 dBm above 11 GHz.
[2] Consult factory for further details.
OFOISR App 06-S-1942
4-Stage
F1098
8.0 to 18.0
250
6.0
2.0
70
40
+10
±40
15
F1099
8.0 to 18.0
500
6.0
2.5
60
40
+3[1]
±40
15
F1201
6.0 to 18.0
450
8.0
2.5
85
65
0 [1]
±80
15
7-Stage
F1200
8.0 to 18.0
500
7.0
2.5
85
65
+3 [1]
±40
15
15
25
20
15
25
20
15
25
23
15
25
23
4.5
4.5
8.0
8.0
40
40
85
85
3
6
7
3
6
7
5
5
[2]
[2]
[2]
[2]
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Open-Loop Bandpass Filter and Driver Specifications
General Specifications
Open-Loop Filters with Drivers
The following specifications are common
to all filters unless otherwise specified in
the model specification tables.
Passband VSWR: 2.0:1 (Best Point)
Input Limiting Level (1 dB compression):
(except for wide-bandwidth filters)
Start Frequency
Below 1 GHz
0 dBm
Above 1 GHz
+10 dBm
Maximum RF Power Without Damage: 1 Watt
CW
Heaters: To minimize fluctuations in
tuned frequency with changes in ambient
temperature the YIG spheres are stabilized by internal, self-regulating heaters. The current drawn by these heaters
varies with the number of stages and the
temperature. Note that there is an initial
current surge when power is first applied
to the heaters which rapidly decays to a
steady state.
+28 VDC Nominal
Heater Current
Surge (max)
2-Stage
4-Stage
6-Stage &
Greater
At Turn-on
0.6 A
1.2 A
1.8 A
25°C Steady State
75 mA
100 mA
200 mA
RF Connectors: Type SMA-Female
Tuning & Heater Terminals: Solder Pins or
Multi-pin Connector (see outline drawings)
Operating Temperature:
Commercial Units: 0°C to +60°C
MIL Units: -55°C to +85°C
Screening Levels: See page 8
OFOISR App 06-S-1942
The filters described in this catalog can be
provided with integral drivers (voltageto-current converters); both analog and
digital drivers are available. The analog
drivers are tuned by a customer-supplied
0-10 Volt ramp. Other voltage ranges are
available if needed. The digital drivers are
tuned by a digital tuning word of up to 12
bits. The input is TTL-compatible, and is
available either latched or non-latched.
Teledyne drivers are especially designed
to reduce the effects of aging. Aging, the
slow change in component values (especially resistors) with time, causes the
voltage-to-frequency transfer characteristic of the filter / driver to change. Trim
potentiometers, used to adjust the driver
to set the filter endpoints, are especially
susceptible to aging. Teledyne matches
every driver to its specific filter using
computer-chosen, select-attest resistors.
This enables the use of potentiometers
with much smaller range, and therefore
minimizes the effect their aging has on
the transfer characteristic.
Teledyne MIL drivers contain all MILspecified parts and are temperature
compensated for operation over the -55
to +85°C range. The resulting static
frequency drift with temperature of the
filter / driver combination is minimized.
Conformal coating of the printed circuit
boards insures survival in the MIL-E5400 Class II airborne environment.
Typical Specifications
Analog Driver:
Tuning Voltage:
0 to +10V (OV = Low-end frequency,
+10V = High-end frequency)
Tuning Impedance: 10KΩ, min.
Power Supply:
+15V±10% at 50 mA
-15V±10% at 50 mA plus tuning coil
current requirements (see individual filter
specification). For example, an F1073
filter will draw an additional 900 mA
when tuned to 18 GHz.
+28V: See appropriate filter specification.
Connector: See appropriate outline draw-
ing.
Digital Driver:
Tuning Input: 12-Bit TTL (All 0’s =
Low-end frequency, All 1’s = High-end
frequency)
Latch (Optional):
Level Triggered (0 = Transparent, 1 =
Latched). Tuning Load: 1 TTL Load
Power Supply:
+15V±10% at 50 mA
-15V±10% at 50 mA plus tuning coil
current requirements (see individual filter
specification). For example, an F1073
filter will draw an additional 900 mA
when tuned to 18 GHz.
+5V at 30 mA
+28V: See appropriate filter specification.
Connector: See appropriate outline draw-
ing
Note that various driver options are available for Teledyne filters. Options include
±12V bias, positive or negative drivers (coil
current drawn from the positive or negative
supply), and various outline configurations.
Please consult factory for details.
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Band-Reject Filters
Introduction
Teledyne band-reject filters are designed
for high performance, producibility, and
maximum reliability in military or commercial systems. Using recent breakthroughs in BRF technology, the overall
“notch” depth and rejection BW is increased while maintaining a minimum 3
dB bandwidth. With a nominal filter skirt
selectivity of up to 96 dB/octave, a 16stage band-reject filter allows the system
designer to “notch out” an undesired signal while sacrificing the smallest possible
system operational bandwidth. Standard
designs with 10-, 12-, and 16-stages are
available in 1.4-inch and 1.7-inch packages. Depending on customer requirements,
Teledyne band-reject filters are available
as a stand-alone filter, filter with analog or
digitally tuned, 12-bit driver. Closed-loop
band-reject filters are also available for
signal suppression applications.
filter designs are fully characterized via
analysis and computer modeling, and then
properly implemented.
The result is a band-reject filter that
exhibits high performance and reliability,
and is inherently producible.
For notch filters with drivers, each
Teledyne driver is individually matched to
its specific filter using computer-selected
resistors to minimize the effects of driver
drift over time. Together with MILspecified components, the Teledyne driver
has been optimized to insure long-term
reliability and operation with a band-reject filter, in any environment, military or
commercial.
Technical Discussion
YIG-tuned band-reject filter bandwidths
are inherently frequency dependent, since
the equivalent circuit can be modeled as a
set of parallel resonant circuits separated
by quarter-wavelength impedance inverters. As such, the filter design can only be
optimized for a single frequency, typically
at the mid-point of the tuning range.
In addition, the individual YIG sphere
coupling bandwidths are proportional to
tuned frequency. The net effect of both
factors is that, unlike the bandpass filter,
whose bandwidth is essentially constant
with frequency, a YIG-tuned notch filter
will have a bandwidth which is approximately proportional to frequency.
As a result, to produce a notch filter with
the ideal characteristics of maximum
rejection BW and notch depth, and
minimum values of 3 dB BW, VSWR,
insertion loss, and spurious, Teledyne
OFOISR App 06-S-1942
Teledyne band-reject filters are available as a stand-alone
filter, filter with analog or digitally tuned, 12-bit driver.
Closed-loop band-reject filters are also available for signal
suppression applications.
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Advanced Band-Reject Filter Technology
Teledyne has developed an “Advanced
Technology” line of band-reject filters
that breaks through conventional size,
specification, and reliability barriers.
♦♦ Enhanced
These band-reject filters (BRF’s) are
smaller, lighter, more reliable, and can
meet extremely deep and wide notch
bandwidth specifications while maintaining a narrow 3 dB bandwidth. While
enjoying the deeper notch and wider
notch bandwidth benefits of 10-, 12-,
and 16-stage designs, spurious levels are
reduced to levels far below those of typical
4- to 8-stage designs. As a result, greater
selectivity is achieved with significantly
reduced spurious levels, on the order of 2
dB (versus conventional spurious levels of
4 to 5 dB). This reduction in spurious and
increase in selectivity, notch depth, and
notch bandwidth was accomplished with
an overall decrease in the filter magnetic
shell size, to a 1.4-inch cube.
♦♦ More
These breakthroughs in BRF technology have resulted in the first production
design of a wideband notch filter that
tunes the entire 4-18 GHz range, in a
single unit.
General characteristics of this advanced
BRF technology include:
♦♦ Reduced
size: 1.4” filter for 10-stage
units; 1.7” for 16-stage and certain 7
& 10-stage units.
♦♦ Increased
skirt selectivity: 60 to 96
dB/octave nominal skirt rolloff.
♦♦ Increased
♦♦ Increased
notch depth: 50 to 100 dB.
notch BW: 60 MHz @ 70
dB for a narrowband 12-stage unit.
♦♦ Decreased
3 dB BW: 100 MHz,
max, for a 60 MHz notch at the 70
dB point.
♦♦ Decreased
spurious: 2-4 dB, typical
for a 12-stage filter.
OFOISR App 06-S-1942
producibility: High production rates.
♦♦ Increased
tuning range: 4-18 GHz in
a single filter.
stages: 10- and 12-stage standard units. 16-stage for 4-18 GHz
units.
♦♦ Increased
es.
reliability: MTBF increas-
These band-reject filters are available
with 12-bit digital or analog drivers, or
as stand-alone units. These units are also
available in closed-loop versions, both the
standard analog version Ferretrac® units
and the latest digital closed-loop version.
(sweep speed, step size, temperature
variations, etc.), the filter will repeat
to within ±500 KHz of the initial
frequency.
3. Since precise frequency set-on is
achieved within the closed-loop
circuitry itself, once the system
processor has specified the frequency
tune word, the processor can proceed
to other system tasks while the filter
tunes itself to precisely the correct
frequency. With the closed-loop filter, the system becomes a “tune and
forget.”
Closed-Loop Band-Reject
Filters
In addition to the traditional open-loop
band-reject filter, Teledyne has pioneered
closed-loop band-reject filter technology.
There are three primary advantages of a
closed-loop solution for band-reject filter
applications:
1. The closed-loop circuit decreases
the time it takes to “set on” the
notch filters. Set-on time is typically decreased by a factor of five,
versus that of the same filter in an
open loop configuration. For a 5-10
GHz closed-loop Ferretrac filter, the
tuning speed for a full band 5 GHz
step is on the order of 3 milliseconds,
to be within ±2 MHz of the final
frequency. This compares to approximately 15 milliseconds for an
open-loop version of the same filter.
2. The filter is set to precisely the
frequency required by the system, to
within ±1 MHz. Furthermore, the
frequency repeatability of the filter
is such that, regardless of conditions
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Band-Reject Filter Parameters / Closed Loop BRF’s
Closed-Loop Band-Reject Filters
Teledyne closed-loop tunable band-reject filters allow a narrow
notch to be positioned precisely over an interfering, or receiver
limiting, signal. This function is particularly useful in integrated
defense electronics systems where interference from adjacent
emitters such as radars and jammers (both hostile and friendly)
can deny use of large segments of receiver bands needed to
identify hostile threats. As with bandpass applications, closedloop technology insures that the notch is where it belongs all the
time, every time. Low passband insertion loss allows cascading of band-reject filters to simultaneously “notch out” multiple
signals without seriously degrading system performance.
Since applications of this device are so varied, consult Teledyne
on your special requirements. The specifications below are examples of our capabilities.
Ferretrac® Band-Reject Filters
Model
Frequency Range [1]
BR (MHz, min)
RB (dB, min)
BW (MHz, max)
IL (dB, max)
ORS (dB, max)
FT1802
1.0-2.0
5
40
125
1.5
4.0
FT1806
2.0-6.0
5
40
125
1.5
4.0
FT1807
6.0-18.0
5
40
140
1.75
4.0
[1] Passband extends from DC to maximum tuned frequency.
Enhanced BRF “Set-On”
Performance
Positioning a relatively narrowband notch on the desired frequency is often a challenge to the system designer. Typically, a
“step tuned” system approach is employed, but this often lengthens processing time and requires additional software capability.
A faster, more accurate approach is to use the Ferretrac® closedloop notch filter. Set-on time is decreased (typically by a factor of
5), the center of the notch can be locked precisely to the desired
signal, and the filter itself can tune to within ±500 KHz of any
desired frequency, regardless of the environmental conditions or
threat environment. The frequency reference signal can be taken
from existing system sources, and can be operated at tuning offset of up to ±300 MHz. Teledyne has just completed the design
of a second-generation, closed-loop filter that offers enhanced
performance, a smaller package, and is ideal for band-reject
filter applications. Use of a closed-loop band-reject filter offers a
system-level solution to the designer’s requirements.
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Band-Reject Filter
RF Parameters See Figure 14
IL
ORS
IL (Insertion Loss): The maximum loss in the passband measured
with the filter turned off or tuned out of the passband.
0 dB
BW
BW (3 dB Bandwidth): The bandwidth measured 3 dB below the
3dB
insertion loss value.
RB
VSWR: Measured in the passband with the filter turned off or
tuned out of the passband frequency range.
ORS (Off Resonance Spurious): The passband attenuation caused
BR
FT
by magnetostatic modes at frequencies offset from the desired
response.
BR (Rejection Bandwidth): The minimum bandwidth required over
which the rejection must be at least rejection level, RB.
FREQ
RB (Rejection Level): The amount of attenuation, referenced to the
insertion loss, of signals within the rejection bandwidth, BR.
Figure 14 RF specification definitions for band-reject filters
Low-Frequency Band-Reject Filters (7- and 16-Stage)
Model
Frequency
Stages
BR (MHz, min)
RB (dB, min)
3 dB BW (MHz, max)
IL (dB, max)
ORS (dB, max)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temperature Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/mA nominal)
Coil Resistance (Ω, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
with analog driver
with digital driver
OFOISR App 06-S-1942
F1300
0.5-2.0
7
3
40
150
1.5
4.0
±3
5
F1310
2-6
16
15
40
125
1.5
4.0
±6
8
F1311
2-8
16
15
40
150
1.5
4.0
±8
10
F1312
2-12
16
10
40
150
1.5
4.0
±10
12
F1016
0.5-1.0
7
5
40
140
1.5
4.0
±3
3
F1302
1.0-2.0
7
5
40
140
1.5
4.0
±3
4
8
12
8
12
10
15
2
20
6
10
6
10
10
20
20
20
10
10
4.5
40
12
90
12
90
10
100
4.5
40
4.5
40
9
11
10
9
11
10
9
11
10
9
11
10
9
11
10
9
11
10
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
High-Frequency Band-Reject Filters (10- and 16-Stage)
Model
Frequency [1]
Stages
BR (MHz, min)
RB (dB, min)
3 dB BW (MHz, max)
IL (dB, max)
ORS (dB, max)
Linearity (MHz, max)
Hysteresis (MHz, max)
Temperature Drift (MHz, max)
0 to 60°C
-55 to +85°C
Tuning Sensitivity
(MHz/mA nominal)
Coil Resistance (Ohms, nominal)
Coil Inductance (mH, nominal)
Outline
Filter
with analog driver
with digital driver
F1323
8-18
10
35
40
150
1.50
4.0
±15
15
F1322
6-18
10
25
40
150
1.50
4.0
±20
20
F1321
4-18
10
10
40
150
1.50
4.0
±20
25
F1333
8-18
16
50
40
150
1.75
4.0
±15
15
F1332
6-18
16
40
40
150
1.75
4.0
±20
20
F1331
4-18
16
25
40
150
1.75
4.0
±20
25
F1330
2-18
16
8
40
200
1.75
4.0
±20
25
15
25
20
15
25
20
15
25
20
15
25
20
15
25
20
15
25
20
20
30
20
8
8
8
8
8
8
8
90
90
90
120
120
120
120
8
[2]
[2]
8
[2]
[2]
8
[2]
[2]
9
[2]
10
9
[2]
10
9
[2]
10
9
[2]
10
1 Passband extends from DC to maximum tuned frequency
2 Consult factory
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Additional Teledyne YIG Products
INSTRUMENTATION.
Teledyne manufactures companion test equipment products utilizing closed-loop YIG filter technology. The C1001 Controller
provides all operating controls and power supplies for the closedloop Ferretrac® filter. Please contact the factory for details on
this product.
Examples of advanced YIG technology include:
16-stage Band-Reject Filter
♦♦
2-18 GHz frequency coverage - in a single filter
♦♦
Increased notch depth
♦♦
Industry’s smallest package size
Multi-function Filters (Single Magnet Designs)
♦♦
Dual 2-stage and Dual 4-stage bandpass filters
♦♦
8-stage band-reject filter with 2-stage bandpass filter
♦♦
10-stage band-reject filter with 4-stage bandpass filter
♦♦
Dual 8-stage band-reject filter
Permanent Magnet Bias (Oscillators and Filters)
♦♦
Smaller size
♦♦
Reduced power consumption
♦♦
Faster tuning speeds
♦♦
Low phase noise oscillators
Vibration Stabilized Designs
♦♦
Reduced residual FM under vibration in oscillators
♦♦
Reduced additive noise in filter
7-Stage Bandpass Filter Design
New YIG Technology From Teledyne
Although YIG devices have been in use for over 30 years,
Teledyne continues to advance the technology. Recent Teledyne
developments include advanced broadband tunable notch filters,
multi-function single-magnet filters, the use of permanent
magnets to enhance YIG component performance, advanced
closed-loop filter design, vibration stabilization techniques, and
YIG-based instrumentation products. Teledyne’s capabilities are
increasing rapidly, and some of the latest technology may not
be included in our catalogs, so please contact the factory or our
local representative for unique solutions to your most challenging
systems problems.
OFOISR App 06-S-1942
♦♦
500 MHz instantaneous bandwidth
♦♦
Increased selectivity and isolation
Advanced Closed-Loop Filter
♦♦
Smaller size
♦♦
Digitally tuned
Instrumentation Products
♦♦
Scalar Network Analyzer enhancements
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Outline Drawings
1.4" BANDPASS FILTER, 2/4-STAGE
OUTLINE #1,(0200009-REV B)
NOTES: (UNLESS OTHERWISE SPECIFIED)
1. DC CONNECTION: SOLDER PINS EI-E4
2. El, E4 LABELED AT THE FACTORY,
LOCATIONS MAY BE REVERSED.
CONN
J1
J2
1.40 [35.56]
FUNCTION
SMA
SMA
El
E2
E3
E4
DC
DC
DC
DC
.15 [3.81]
MAX
.70 [17.78]
PIN NO.
RF INPUT
RF OUTPUT
COIL +
HEATER
HEATER
COIL -
J1
1.40 [35.56]
.70 [17.78]
J2
. XX
. XXX
.38 [9.53]
TYP
1.4" BANDPASS FILTER W/ANALOG DRIVER
OUTLINE #2 (0200005-REV B)
LABEL AREA
.12 MAX
[3.0]
.46 MAX
[11.7]
.70 2 PL
[17.8]
2.15
[54.6]
1.02
[25.9]
.90 2 PL
[22.9]
.13
[3.3]
2.620
[66.55]
1.62
[41.1]
TOLERANCE
[.76]
*.03
*.005
[.127]
INCHES [MILLIMETERS]
NOTES: (UNLESS OTHERWISE SPECIFIED)
1. DC CONNECTOR: ITT CANNON DE-9P
(MATING CONN. DE-9S
OR EQUVALENT)
CONN - PIN NO.
Jl
SMA
SMA
J2
DC
1
2
3
4
5
6
7
8
DC
9
FUNCTION
RF IN
RF OUT
+15V DC
COMMON
-l5V DC
V TUNE
N/C
N/C
HEATER +2BV DC
HEATER RETURN
N/C
#6-32 UNC-2B X .30 [7.6] DP.
4 PLACES (HELICOIL INSERT)
.15
[3.8]
1.40
[35.6]
1.100
[27.94]
. XX
. XXX
TOLERANCE
[.76]
*.03
*.005
[.127]
INCHES [MILLIMETERS]
2.90
[73.66]
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Outline Drawings
1.7" BANDPASS FILTER, 2/4-STAGE
OUTLINE #3,
.15 [3.8]
(0200010-REV B)
1.70 [43.2]
1.70 [43.2]
.85 [22]
1.70 [43.2]
LABEL AREA
J1
E1
J1
E2
E3
E4
J2
.85 [22]
.38 [9.5]
TYP
2.0" BANDPASS FILTER, 4-STAGE
OUTLINE #4,
(0200066-REV A)
CONN
J1
J2
DC
DC
DC
DC
PIN NO.
SMA
SMA
E1
E2
E3
E4
FUNCTION
RF INPUT
RF OUTPUT
MAIN COIL
HEATER
HEATER
MAIN COIL
TELEDYNE
MICROWAVE
1.7" BANDPASS FILTER, 7-STAGE
OUTLINE #5, (0200120-REV A)
NOTES: (UNLESS OTHERWISE SPECIFIED)
1. DC CONNECTION: SOLDER PINS, El-E4.
J1
E1 E2 E3 E4
1.70
2. El,E4 LABELED AT THE FACTORY,
LOCATIONS MAY BE REVERSED.
CONN
J1
J2
[43.2]
.85
[21.6]
DC
DC
DC
DC
PIN NO.
SMA
SMA
E1
E2
E3
E4
FUNCTION
RF INPUT
RF OUTPUT
COIL +
HEATER
HEATER
COIL -
.54
[13.7]
1.70
1.70
[43.2]
[43.2]
. XX
. XXX
TOLERANCE
[.76]
*.03
*.005
[.127]
INCHES [MILLIMETERS]
OFOISR App 06-S-1942
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Outline Drawings
1.7" BANDPASS FILTER W/ANALOG DRIVER
OUTLINE #6, (0200091-REV 1)
J2 (RF OUTPUT)
LABEL AREA
CHAMFER .12 X 45°
2 PLCS
R .22, 2 PLCS
NOTES: (UNLESS OTHERWISE SPECIFIED)
1. DC CONNECTOR: POSITRONIC SMPL9MOTOLB
(MATING CONN. SGMC9FOT0000
OR EQUIVALENT)
.24
[6.1]
CONN-PIN-FUNCTION
J1SMA- RF INPUT
J2SMA- RF OUTPUT
A
J3+ 15 V
B
COMMON
-15 V
C
D
HTR +
E
HTR F
N/C
N/C
H
J
V TUNE +
J3V TUNE K
J1 (RF INPUT)
.85 2 PL
[22] 2 PL
J3
J1
1.95
[49.5]
"A" PIN
1.10 2 PL
[27.9] 2 PL
1.07
[27.2]
2.95
[74.9]
.80
[20]
2.00
[50.8]
#6-32 UNC-2B X .20 DP.
HELICOIL INSERT
6 PLACES
1.500
[38.10]
1.500
[38.10]
.25
[6.3]
2.320
[58.93]
.44
[11]
J2 (RF OUTPUT)
1.7" BANDPASS FILTERW/DIGITAL DRIVER
OUTLINE #7, (0200074-REV
LABEL AREA
CHAMFER .12 X 45°
2 PLCS
R .22, 2 PLCS
NOTES: (UNLESS OTHERWISE SPECIFIED)
1, DC CONNECTOR: POSITRONIC SMPL26MOTOLB
(MATING CONN. MC26FOT0000
OR EQUIVALENT)
.19
[4.83]
J1 (RF INPUT)
CONN
J1
J2
J3
J3
OFOISR App 06-S-1942
PIN NO.SMA
SMA
A
B
C
D
E
F
H
J
K
L
M
N
P
R
S
T
U
V
W
X
Y
Z
a
b
c
d
FUNCTION
RF INPUT
RF OUTPUT
LATCH
BIT 11
BIT 12 (LSB)
N/C
BIT 9
BIT 10
N/C
BIT 7
BIT 8
+15V
BIT 5
BIT 6
COMMON
BIT 3
BIT 4
-15V
BIT 1 (MSB)
BIT 2
N/C
N/C
+5V
N/C
N/C
N/C
+28V
-28V RTN
.85 2 PL
[22] 2 PL
MALE PIN
"A" PIN
J3
J1
1.95
[49.5]
2.00
[50.8]
1.10 2 PL
[27.9] 2 PL
.57
[15]
2.08
[52.7]
3.35
[85.1]
1.500
[38.10]
2.00
[50.8]
1.500
[38.10]
.44
[11]
#6-32 UNC-2B X
.20 DP. HELICOIL
INSERT, 6 PLACES
.25
[6.3]
2.760
[70.10]
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Outline Drawings
1.4" BAND-REJECT FILTER
OUTLINE #8, (0200113-REV A)
CONN
J1
J2
PIN NO.
FUNCTION
SMA
SMA
El
E2
E3
E4
DC
DC
DC
DC
1.40
[35.6]
.15
[3.8]
1.40
[35.6]
RF INPUT
RF OUTPUT
COIL +
HEATER
HEATER
COIL -
.57
[4.3]
. XX
. XXX
.17 TYP
[4.3]
TOLERANCE
[.76]
*.03
*.005
[.127]
INCHES [MILLIMETERS]
LABEL AREA
.39
[9.9]
.38
[9.6]
4X .12 [3] X 45°
CHAMFER
.63
[16.0]
J2
J1
E1 E2 E3 E4
1.40
[35.6]
.70
[17.8]
1.7" BAND-REJECT FILTER
OUTLINE #9,(0200114-REV 1)
CONN
J1
J2
PIN NO.
DC
DC
DC
DC
1.70
[43.2]
.15
[3.8]
. XXX
.57
[4.3]
FUNCTION
SMA
SMA
El
E2
E3
E4
. XX
RF INPUT
RF OUTPUT
COIL +
HEATER
HEATER
COIL -
1.70
[43.2]
TOLERANCE
[.76]
*.03
*.005
[.127]
INCHES [MILLIMETERS]
.17 TYP
[4.3]
LABEL AREA
.38
[9.6]
.54
[13.7]
4X .12 [3] X 45°
CHAMFER
.63
[16.0]
J2
J1
E1E2 E3 E4
1.70
[43.2]
.85
[21.6]
1.7" BAND-REJECT FILTER W/DIGITAL DRIVER
OUTLINE #10, (0200115-REV 1)
CHAMFER .12 X 45°
2 PLCS
.23 TYP.
[5.7]
J1
J2
CONN
J1
J2
J3
.19
[4.83]
FEMALE PIN
.63 TYP.
[16]
.54 TYP.
[14]
IDENT
LABEL
MODEL # FDXXXX
S/N: XXXX D/C: YYWW
TELEDYNE
MICROWAVE
R .22, 2 PLCS
"A" PIN
P1
2.00
[50.8]
1.95
[49.5]
1.10 TYP.
[27.9]
2.08
[52.7]
OFOISR App 06-S-1942
.57
[15]
J3
NOTES: (UNLESS OTHERWISE SPECIFIED)
DC CONNECTOR: POSITRONIC SMPL26MOTOLB
(MATING CONN.
OR EQUIVALENT)
PIN NO.- FUNCTION
SMA RF INPUT
SMA RF OUTPUT
A
LATCH
B
BIT 11
C
BIT 12 (LSB)
D
N/C
E
BIT 9
F
BIT 10
H
N/C
J
BIT 7
K
BIT 8
L
+15V
M
BIT 5
N
BIT 6
P
COMMON
R
BIT 3
S
BIT 4
T
-15V
U
BIT 1 (MSB)
V
BIT 2
W
N/C
X
N/C
Y
+5V
TOLERANCE
Z
N/C
[.76]
*.03
. XX
a
N/C
b
N/C
. XXX *.005
[.127]
c
+28V
INCHES [MILLIMETERS]
d
-28V RTN
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]
Outline Drawings
1.7" BAND-REJECT FILTER W/ANALOG DRIVER
OUTLINE #11,(0200182-REV 1)
CHAMFER .12 X 45°
LABEL AREA
2 PLCS
CONN-PIN-FUNCTION
J1SMA- RF INPUT
J2SMA- RF OUTPUT
A
J3+ 15 V
B
COMMON
-15 V
C
D
HTR +
E
HTR F
N/C
N/C
H
J
V TUNE +
J3V TUNE K
R .22, 2 PLCS
.23
[5.7]
.24
[6.1]
.54
[13.7]
.62
[15.7]
J1
.80
[20]
P1
J2
"A" PIN
1.95
[49.5]
1.10
[27.9]
1.07
[27.2]
2.95
[74.9]
#6-32 UNC-2B
X .20 DP HELICOIL
INSERT, 6 PLACES
FERRETRAC (CLOSED-LOOP) FILTER
OUTLINE #12, (0200001-REV
1.500
[38.10]
2.00
[50.8]
.12
[3.2]
1.875
[47.63]
.12
[3.2]
4 MOUNTING HOLES
.156 [3.9] DIA THRU
1.500
[38.10]
.44
[11]
2.320
[58.93]
2.75
[69.9]
3.25
[82.5]
4.48 MAX
.25
[6.3]
3.000
[76.20]
CONN
J1
J2
J3
3.75 MAX
[95.2]
[113.7]
.62
[15.7]
NOTES: (UNLESS OTHERWISE SPECIFIED)
1, DC CONNECTOR: ITT CANNON DE-9P
(MATING CONN. DE-9S
OR EQUIVALENT)
.88
[22.3]
PIN NO.SMA
SMA
SMA
1
2
3
4
5
6
7
8
9
J3
.88
[22]
J1
FUNCTION
RF INPUT
RF OUTPUT
REF IN
+15V DC
GND
-15V DC
V TUNE
SAMPLE & HOLD
LOCK INDICATOR
HEATER +28V
HEATER RETURN
(FACTORY TST PT.)
.62
[15.7]
J3
J2
2.18
[55.3]
.78
[20]
1.06
[26.8]
OFOISR App 06-S-1942
2.13
[54.0]
3.05 MAX.
[77.5]
TELEDYNE
MICROWAVE
.25
[6.4]
MODEL #
S/N:
2.18
[55.3]
D/C:
MADE IN USA
DC CONNECTOR TYPE
DE-9P ITT CANNON
OR EQUIVALENT
FERRETEC PRODUCT
LABEL
1274 Terra Bella Avenue, Mountain View, CA 94043
Tel: 1.800.832.6869 or +1.650.962.6944 Fax: +1.650.962.6845
[email protected]