Data Sheet(pdf)

Hartcran House, 231 Kenton Lane, Harrow, Middlesex, HA3 8RP, England
Tel: +44 (0) 20 8909 9595, Fax: +44 (0) 20 8909 2233, www.radiometrix.com
PRELIMINARY
SAT3
Issue 1, 27 January 2012
869MHz Narrow Band FM Transmitter
The SAT3 transmitter modules offer a 10mW
RF output UHF data link in Radiometrix SIL
standard pin-out and footprint. This makes the
SAT3 ideally suited to low power applications
using narrow band transmitters. Together with
the matching SAR3 receiver a one-way radio
data link can be achieved over a distance up to
1km+ with suitable choice of data rate and
antennas.
Features
Conforms to EN 300 220-3 and EN 301 489-3
Standard frequency 869.2125MHz
25 kHz channel spacing
Data rates up to 4kbps
Usable range over 1km+
Fully screened
Low power requirements
Figure 1: SAT3 transmitter
The SAT3 is a narrow band radio transmitter module for use in long range data transfer applications at
ranges up to 1kilometre+
Applications
Automatic meter reading (AMR)
Car and building security
Social alarms
Industrial telemetry and telecommand
In-building environmental monitoring and control
EPOS and inventory tracking
Technical Summary
Size: 32 x 13.5 x 4.5mm
Operating frequency: 869.2125MHz
Supply range: 5v
Current consumption: 45mA Max
Data bit rate: 4kbps max.
Transmit power: 10dBm (10mW) nominal
Evaluation platforms: Universal Evaluation Kit, NBEK + SIL carrier
Radiometrix Ltd.,
SAT3 transmitter data sheet
Page 1
Figure 2: SAT3 Block diagram
Functional description
The SAT3 transmitter consists of a frequency modulated Voltage Controlled Temperature Controlled Crystal
Oscillator (VCTCXO) feeding a frequency multiplier with two stage amplifier and RF filter. Operation can be
controlled by the EN (Enable) line, the transmitter achieving full RF output typically within 1.5ms of this line
being pulled high. The RF output is filtered to ensure compliance with the appropriate radio regulations and
fed to the 50Ω antenna pin.
User interface
4.5 mm
32 mm
12.0
mm
12.5
mm
SAT3
Radiometrix
PCB level
15.24 mm
1
2
3
4
5
6
7
1 = RF GND
2 = RF OUT
3 = RF GND
4 = En
5 = Vcc
6 = 0V
7 = TXD
7 holes, 0.7 mm dia, pin spacing 2.54 mm
Figure 3: SAT3 pin-out and dimension
ENT1L pin
1, 3
2
4
5
6
7
Name
RFgnd
RF out
EN
VCC
0V
TXD
Function
RF Ground
50 RF input from the antenna
Pull high to enable Transmitter (Note 1)
5V DC power supply
Ground
DC coupled input for 5V CMOS logic. Rin = 200kΩ
NOTES:
1. EN pin should not be left floating
Radiometrix Ltd.,
SAT3 transmitter data sheet
Page 2
Absolute maximum ratings
Exceeding the values given below may cause permanent damage to the module.
Operating temperature
Storage temperature
-20°C to +60°C
-30°C to +70°C
RF in (pin 1)
VCC (pin 5)
EN (pin 4)
All other pins
±50V @ <10MHz, +13dBm @ >10MHz
-0.3V to +16V
-0.3V to +16V
-0.3V to +5.5V
Performance specifications
(Vcc = 5V / temperature = 25°C unless stated)
General
DC supply
Supply voltage
TX Supply current @ 10mW
Antenna pin impedance
RF centre frequency
Channel spacing
Number of channels
RF
RF power output
Spurious emissions
Adjacent channel TX power
Frequency accuracy
FM deviation (peak)
Baseband
Modulation bandwidth @ -3dB
TXD input level (logic low)
TXD input level (logic high)
pin
min.
typ.
max.
units
5
5
2
3.1
5
38
50
869.2125
25
1
16
45
V
mA
+9
+10
+11
-2.5
±2.5
> -40
0
±3
+2.5
±3.5
2
2
0
7
7
Dynamic timing
TX select to full RF
Notes:
1.
2.
3.
4.
5.
notes
MHz
kHz
3
0
5
4.0
1.5
2
dBm
dBm
dBm
kHz
kHz
1
5
2
3
kHz
V
V
4
4
ms
Measured into 50Ω resistive load.
Total over full supply and temperature range.
With 0V – 5.0V modulation input.
To achieve specified FM deviation.
Meets EN300-220
Radiometrix Ltd.,
SAT3 transmitter data sheet
Page 3
Applications information
Power supply requirements
The SAT3 has a built-in regulator which delivers a constant 3V to the transmitter frequency control and RF
circuitry when the external supply voltage is 3.1V or greater. This ensures constant frequency stability and
removes the need for external supply decoupling except in cases where the supply rail is extremely poor
(ripple/noise content >0.1Vp-p).
TX modulation requirements
The module is factory-set to produce the specified FM deviation with a TXD input to pin 14 of 5V amplitude,
i.e. 0V “low”, 5V “high (other variants available on request)
If the data input level is greater than 5V, a resistor must be added in series with the TXD input to limit the
modulating input voltage to a maximum of 5V on pin 7. TXD input resistance is 200kΩ to ground.
Expected range
Predicting the range obtainable in any given situation is notoriously difficult since there are many factors
involved. The main ones to consider are as follows:
•
•
•
•
•
Type and location of antennas in use
Type of terrain and degree of obstruction of the link path
Sources of interference affecting the receiver
“Dead” spots caused by signal reflections from nearby conductive objects
Data rate and degree of filtering employed
The following are typical examples – but range tests should always be performed before assuming that a
particular range can be achieved in a given situation:
Data rate
1.2kbps
Note:
Tx antenna
half-wave
Rx antenna
half-wave
Environment
rural/open
Range
1000m +
The figure for 1.2kbps assumes that the receiver bandwidth has been suitably reduced by utilising an
outboard sallen-key active audio filter and data slicer or similar arrangement.
The SAT3’s TXD input is normally driven directly by logic levels but will also accept analogue drive (e.g. 2tone signalling). In this case it is recommended that TXD (pin 14) be DC-biased to 2.5V approx. with the
modulation ac-coupled and limited to a maximum of 5Vp-p to minimise distortion over the link.
Although the modulation bandwidth of the SAT3 extends down to DC it is not advisable to use data
containing a DC component. This is because frequency errors and drifts between the transmitter and
receiver occur in normal operation, resulting in DC offset errors on the receiver’s audio output.
Module mounting considerations
The modules may be mounted vertically or bent horizontal to the motherboard.
Good RF layout practice should be observed. If the connection between module and antenna is more than
about 20mm long use 50Ω microstrip line or coax or a combination of both. It is desirable (but not essential)
to fill all unused PCB area around the module with ground plane.
Variants and ordering information
The SAT3 transmitter is manufactured in the following variant as standard:
SAT3-869.2125-3 (869.2125MHz)
Matching Receiver:
SAR3-869-8
Radiometrix Ltd.,
SAT3 transmitter data sheet
Page 4
Radiometrix Ltd
Hartcran House
231 Kenton Lane
Harrow, Middlesex
HA3 8RP
ENGLAND
Tel: +44 (0) 20 8909 9595
Fax: +44 (0) 20 8909 2233
[email protected]
www.radiometrix.com
Copyright notice
This product data sheet is the original work and copyrighted property of Radiometrix Ltd. Reproduction in
whole or in part must give clear acknowledgement to the copyright owner.
Limitation of liability
The information furnished by Radiometrix Ltd is believed to be accurate and reliable. Radiometrix Ltd
reserves the right to make changes or improvements in the design, specification or manufacture of its
subassembly products without notice. Radiometrix Ltd does not assume any liability arising from the
application or use of any product or circuit described herein, nor for any infringements of patents or other
rights of third parties which may result from the use of its products. This data sheet neither states nor
implies warranty of any kind, including fitness for any particular application. These radio devices may be
subject to radio interference and may not function as intended if interference is present. We do NOT
recommend their use for life critical applications.
The Intrastat commodity code for all our modules is: 8542 6000.
R&TTE Directive
After 7 April 2001 the manufacturer can only place finished product on the market under the provisions of
the R&TTE Directive. Equipment within the scope of the R&TTE Directive may demonstrate compliance
to the essential requirements specified in Article 3 of the Directive, as appropriate to the particular
equipment.
Further details are available on The Office of Communications (Ofcom) web site:
http://www.ofcom.org.uk/radiocomms/ifi/
Information Requests
Ofcom
Riverside House
2a Southwark Bridge Road
London SE1 9HA
Tel: +44 (0)845 456 3000 or 020 7981 3040
Fax: +44 (0)20 7783 4033
[email protected]
European Radiocommunications Office (ERO)
Peblingehus
Nansensgade 19
DK 1366 Copenhagen
Tel. +45 33896300
Fax +45 33896330
[email protected]
www.ero.dk
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