AN11068 - NXP Semiconductors

AN11068
BGU8007/BGU7005 Matching Options for Improved LTE
Jammer Immunity
Rev. 2 — 30 May 2012
Application Note
Document information
Info
Content
Keywords
LNA, GNSS, GPS, BGU8007, BGU7005
Abstract
This document describes several matching topologies for the BGU8007
and BGU7005 LNAs. These topologies provide additional immunity to
700 MHz LTE band jammers.
AN11068
NXP Semiconductors
BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Revision history
Rev
Date
Description
2
Added BGU8007 information, updated matching topology
20120530
Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
1. Introduction
The BGU8007 and BGU7005 are low-noise amplifiers dedicated for Global Navigation
Satellite System (GNSS) receiver applications. They are both offered in plastic leadless
6-pin SOT886 packages. The BGU8007 uses NXP’s eighth generation 180 GHz fT
SiGe:C process, has typical gain of 19 dB and typical noise figure of 0.75 dB, and can be
operated at collector voltages up to 2.5V. The BGU7005 uses NXP’s seventh generation
110 GHz fT SiGe:C process, has typical gain of 16.5 dB and typical noise figure of 0.85
dB, and can be operated at collector voltages up to 3.1V. Both parts contain a single RF
stage and are supplied with an enable function allowing them to be controlled using logic
signals. Each MMIC also features temperature-stabilized bias circuitry. Product
datasheets and several supporting user manuals are available for the BGU8007 and
BGU7005.
•
BGU8007 Datasheet: SiGe:C Low Noise Amplifier MMIC for GPS,
GLONASS, and Galileo
•
BGU7005 Datasheet: SiGe:C Low Noise Amplifier MMIC for GPS,
GLONASS, and Galileo
•
User Manual for the BGU8007 GPS LNA Evaluation Board (UM10497)
•
User Manual for the BGU7005 GPS LNA evaluation board (UM10380)
•
User Manual for the BGU7005 GPS Front End evaluation board
(UM10381)
•
2-Tone Test BGU7005 and BGU7007 GPS LNA (UM10453)
In the cases of both the BGU8007 and the BGU7005, only two external components are
required to build the baseline application circuits: a decoupling capacitor on the collector
feed and a low-cost series inductor for RF input matching. The outputs of the parts are
internally matched for GNSS frequencies. This application note will outline additional
options for modifying the input match to provide increased immunity for the LNA in the
presence of LTE band signals. Although this note deals specifically with the BGU8007
and BGU7005, the techniques presented here are applicable to the entire family of NXP
GNSS LNAs.
The baseline input matches provide high gain, low current consumption, high linearity,
and lowest noise figure. In the specific case of operating the BGU8007 or BGU7005 in
the presence of LTE band jammers, the input match can be modified to provide
additional immunity to these signals. The basic premise is to add additional low cost
components to the input match in order to provide a gain null in the 700 MHz LTE band.
This technique can potentially reduce or alleviate the need for relatively high cost filtering
in the system.
Figure 1 below shows the broadband gain performance of the BGU8007 with baseline
single element input match and a 3-element jammer immunity input match which creates
the 700 MHz gain null.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
20
10
0
Gain
(dB)
-10
Baseline
-20
3-Element
-30
-40
0
400
800
1200
1600
2000
Frequency (MHz)
Fig 1.
Gain Roll-off Comparison for Baseline and LTE Jammer Immunity Matching Options
BGU8007 1.8V
2. Baseline Single Element Match Performance BGU7005
Both the standard BGU8007 and BGU7005 evaluation boards are supplied with a Murata
LQW15 series inductor (0402 size) in the input match. This type of high quality factor (Q)
inductor is recommended in order to provide best noise performance. Figure 2 and
Table 1 below show the schematic and bill of materials for the BGU8007 baseline circuit,
while Figure 3 and Table 2 show the BGU7005 baseline circuit. The baseline
configuration application board, used for both the BGU8007 and BGU7005, is shown in
Figure 4. The broadband gain and input/output return loss are shown in Figures 5 and 6
for the BGU8007 and BGU7005, respectively.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 2.
BGU8007 Baseline Schematic
Table 1.
List of Components for Baseline Input Match BGU8007
For schematic see Figure 2
Component
Description
Value
Supplier
C1
Decoupling Capacitor
1nF
Various
L1
Input Matching
5.6nH
Murata LQW15
IC1
BGU8007
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Application Note
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 3.
BGU7005 Baseline Schematic
Table 2.
List of Components for Baseline Input Match BGU7005
For schematic see Figure 3
Component
Description
Value
Supplier
C1
Decoupling Capacitor
1nF
Various
L1
Input Matching
5.6nH
Murata LQW15
IC1
BGU7005
AN11068
Application Note
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NXP
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 4.
BGU8007/BGU7005 Baseline Board Layout
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NXP Semiconductors
BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
0
20
-5
10
-10
Gain
(dB)
RL
(dB)
-15
0
-20
IRL
-10
ORL
-25
-20
0
1000
2000
3000
-30
0
Frequency (MHz)
a.
Fig 5.
1000
2000
3000
Frequency (MHz)
b.
Gain vs. Frequency
Gain and Return Loss vs. Frequency
Input and Output Return Loss vs. Frequency
Baseline Match BGU8007
20
0
10
-5
Gain
(dB)
RL
(dB)
0
-10
-10
-15
IRL
ORL
-20
-20
0
1000
2000
3000
0
Fig 6.
Application Note
3000
b. Input and Output Return Loss vs. Frequency
Gain and Return Loss vs. Frequency
AN11068
2000
Frequency (MHz)
Frequency (MHz)
a. Gain vs. Frequency
1000
Baseline Match BGU7005
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
One method to judge the linearity of an LNA under jamming conditions is an out-of-band
second-order spurious product measurement. At average power levels received by a
GNSS receiver under normal conditions, the system will not have in-band
intermodulation problems caused by the GNSS signal itself. Strong out-of-band transmit
frequency jammers can cause linearity problems, however. For example, two incident
700MHz LTE band signals can cause a 2nd order spurious product which falls in the
GNSS band to be produced in the LNA.
fspur = f1 + f2 ~ GNSS band
Specific to this application note, two input signals of equal amplitude at 787.4 MHz and
788.0 MHz are applied to the input of the LNAs, producing a 2nd order spurious in the
GNSS band.
787.4 MHz + 788.0 MHz = 1575.4 MHz
Figure 7 below shows the measured results of this two-tone test for the baseline
BGU8007 input match. The level of the 2nd order spurious product and the output level
of the f1 fundamental product are plotted as a function of single tone input power. Figure
8 shows the same information for the BGU7005 in its baseline configuration.
10
-10
-30
Pout
(dBm)
-50
-70
f1 Fundamental
IM2
-90
-110
-70
-60
-50
-40
-30
-20
-10
0
Pin Single Tone (dBm)
Fig 7. Two Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575.4 MHz) Baseline Match
BGU8007 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
0
-20
-40
Pout
(dBm)
-60
-80
f1 Fundamental
IM2
-100
-120
-70
-60
-50
-40
-30
-20
-10
Pin Single Tone (dBm)
Fig 8. Two Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575.4 MHz) Baseline Match
BGU7005 1.8V
Another important consideration is the level of the 2nd order harmonic product, which is
generated by the device at twice the frequency of an incident tone.
fharm (2nd order) = 2f1 ~ GNSS band
Again specific to this note, an input frequency of 788 MHz produces a 2nd order harmonic
in the GNSS band, at 1576 MHz. Figure 9 shows the level of the 2nd order harmonic as a
function of input power of the 788 MHz tone, as well as collector current as a function of
input power, for the BGU8007. Figure 10 provides the same information for the
BGU7005.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
14
0
12
-20
10
Pout
(dBm)
-40
8
Pout
(dBm)
-60
6
4
-80
2
-100
Fundamental
2nd Harmonic
0
-70 -60 -50 -40 -30 -20 -10
-120
0
-70 -60 -50 -40 -30 -20 -10
Pin (dBm)
0
Pin (dBm)
a.
Current vs Pin
b.
Fig 9.
Single Tone Test Results f1 = 788 MHz
Pout vs. Pin
Baseline Match BGU8007 1.8V
0
14
12
-20
10
Icc
(mA)
-40
8
Pout
(dBm)
6
-60
4
Fundamental
-80
2
0
-70
-60
-50
-40
-30
-20
-10
2nd Harmonic
-100
0
-70
-60
-50
Pin (dBm)
a.
b.
Fig 10. Single Tone Test Results f1 = 788 MHz
Application Note
-30
-20
-10
0
Pin (dBm)
Current vs. Pin
AN11068
-40
Pout vs. Pin
Baseline Match BGU7005 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Figures 11 and 12 show the GNSS-band noise figure for a BGU8007 and BGU7005
sample, respectively. Note that these data are with no jammer signals present, and also
include printed circuit board and SMA connector losses.
Fig 11. BGU8007 Baseline Match 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 12. BGU7005 Baseline Match 1.8V
3. Input Match for LTE Jammer Immunity
To increase immunity to LTE band signals, the input match can be modified to a threeelement topology, providing a gain null in the response of the LNA circuit at 700 MHz
LTE band frequencies. The additional elements are a low cost chip capacitor and low
cost chip inductor. See Figure 13 and Table 3 for schematic and bill of materials for the
BGU8007, and Figure 14 and Table 4 for the BGU7005. Figure 15 shows the updated
application board, with the location of the L1-C2 network.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 13. BGU8007 LTE Jammer Immunity Match Schematic
Table 3.
List of Components for LTE Jammer Immunity Input Match BGU8007
For schematic see Figure 13
Component
Description
Value
Supplier
C1
Input Matching
1.8pF
L1
Input Matching
6.2nH
Murata LQW15
C2
Input Matching
6.8pF
Murata GRM15
C3
Decoupling Capacitor
1nF
Various
IC1
BGU8007
AN11068
Application Note
-
Murata GJM15
NXP
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 14. BGU7005 LTE Jammer Immunity Match Schematic
Table 4.
List of Components for LTE Jammer Immunity Input Match BGU7005
For schematic see Figure 14
Component
Description
Value
Supplier
C1
Input Matching
2.4pF
Murata GJM15
L1
Input Matching
6.2nH
Murata LQW15
C2
Input Matching
6.8pF
Murata GRM15
C3
Decoupling Capacitor
1nF
Various
IC1
BGU7005
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Shunt L-C addition
Fig 15. BGU8007/BGU7005 LTE Jammer Immunity Board Layout
As can be seen in Figures 16 and 17 for the BGU8007 and BGU7005, respectively, the
input match provides a gain null around 780 MHz. The gain null serves to reduce the
level of 2nd order distortion in the GNSS band.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
20
0
-5
0
-10
RL
-15
(dB)
Gain
(dB)
-20
-20
IRL
ORL
-25
-30
-40
0
1000
2000
0
3000
1000
2000
3000
Frequency (MHz)
Frequency (MHz)
a. Gain vs. Frequency
b. Input and Output Return Loss vs. Frequency
Fig 16. Gain and Return Loss vs. Frequency LTE Jammer Immunity Match BGU8007 1.8V
20
0
0
-10
Gain
(dB)
RL
(dB)
-20
-20
IRL
ORL
-40
0
1000
2000
-30
3000
0
Frequency (MHz)
a.
Gain vs. Frequency
1000
2000
3000
Frequency (MHz)
b.
Input and Output Return Loss vs. Frequency
Fig 17. Gain and Return Loss vs. Frequency LTE Jammer Immunity Match BGU7005 1.8V
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Figure 18 shows the test results for the two-tone test using the three-element jammer
immunity match for the BGU8007. Compared to the baseline case, the level of the 2nd
order spurious product is greatly reduced and the part remains at the quiescent current
level for much higher input power levels. For instance, for a single tone input power of
-30 dBm, the 2nd order spurious product is measured as -104 dBm, compared to -42 dBm
for the baseline configuration. Figure 19 shows the test results for the BGU7005.
0
-20
-40
-60
Pout
(dBm)
-80
f1 Fundamental
IM2
-100
-120
-140
-50
-40
-30
-20
-10
0
10
20
Pin Single Tone (dBm)
Fig 18. Two-Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575. MHz) LTE Jammer Immunity Match
BGU8007 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
0
-20
-40
-60
Pout
(dBm)
-80
f1 Fundamental
-100
IM2
-120
-140
-50
-40
-30
-20
-10
0
10
20
Pin Single Tone (dBm)
Fig 19. Two-Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575.4 MHz) LTE Jammer Immunity Match
BGU7005 1.8V
Figure 20 shows the 2nd harmonic level as well as the collector current draw as a function
of 788 MHz input power (single tone input) for the BGU8007 with the jammer immunity
match. As with the 2nd order spurious product from the two-tone test, the 2nd order
harmonic product from the single tone test is drastically reduced compared to the
baseline case. For -30 dBm input power, the 2nd order harmonic is measured as -108
dBm compared to -38 dBm for the baseline. Figure 21 shows the 2nd harmonic plot for
the BGU7005. Also note from the figures that the 788 MHz input power must be greater
than 0 dBm for the current draw of the devices to move appreciably above their
quiescent levels.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
0
10
-20
8
-40
6
-60
Icc
(mA)
Pout
(dBm)
-80
4
-100
2
Fundamental
-120
0
-50
-40
-30
-20
-10
0
10
20
2nd Harmonic
-140
-50 -40 -30 -20 -10
Pin (dBm)
0
10
20
Pin (dBm)
a. Current vs. Pin
b. Pout vs. Pin
Fig 20. Single Tone Test Results f1 = 788 MHz
LTE Jammer Immunity Match BGU8007 1.8V
0
10
-20
8
-40
6
-60
Icc
(mA)
Pout
(dBm)
-80
4
2
0
-50
-40
-30
-20
-10
0
10
20
-100
Fundamental
-120
2nd Harmonic
-140
-40
-30
Pin (dBm)
0
10
20
b. Pout vs. Pin
Fig 21. Single Tone Test Results f1 = 788 MHz
Application Note
-10
Pin (dBm)
a. Current vs. Pin
AN11068
-20
LTE Jammer Immunity Match BGU7005 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Finally, Figure 22 shows the noise figure for a BGU8007 sample with the 3-element LTE
jammer immunity match. There is some slight degradation in noise figure due to
additional components on the input of the MMIC. Figure 23 shows the NF result for a
BGU7005 sample. As with the baseline case, these noise figure data include board and
connector losses, and are taken with no jammer present.
Fig 22. BGU8007 LTE Jammer Immunity Match 1.8V
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Fig 23. BGU7005 LTE Jammer Immunity Match 1.8V
4. Two-element Compromise Input Match
The 3-element matching option outlined in Section 3 provides the best-case performance
in cases where 2nd order distortion performance of a 700 MHz band jammer(s) is
paramount, whereas the baseline match provides the simplest solution and lowest noise
figure. In cases where component count or board space is critical, yet 700 MHz 2nd order
distortion performance is still a concern, the input match can be modified to a 2-element
high-pass topology. This “series-C shunt-L” topology decreases the gain of the LNA
circuit in the 700 MHz LTE-band, but not as much as the 3-element jammer immunity
solution. Please see Figure 24 and Table 5 for the 2-element compromise match
schematic and bill of materials for the BGU8007. Figure 25 and Table 6 show the
schematic and bill of materials for the BGU7005.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 24. BGU8007 Two-element Match Schematic
Table 5.
List of Components for Two Element Input Match BGU8007
For schematic see Figure 24
Component
Description
Value
Supplier
C1
Input Matching
2.0pF
Murata GJM15
L1
Input Matching
5.1nH
Murata LQW15
C2
Decoupling Capacitor
1nF
Various
IC1
BGU8007
AN11068
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NXP
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 25. BGU7005 Two-element Match Schematic
Table 6.
List of Components for Two Element Input Match BGU7005
For schematic see Figure 25
Component
Description
Value
Supplier
C1
Input Matching
2.4pF
Murata GJM15
L1
Input Matching
5.1nH
Murata LQW15
C2
Decoupling Capacitor
1nF
Various
IC1
BGU7005
-
NXP
This alternative steepens the gain roll-off below the GNSS band but does not provide a
gain null. Figures 26 and 27 show the broadband gain response, plus the input and
output return loss of the part for the two-element input match case for the BGU8007 and
BGU7005, respectively.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
20
0
-5
0
RL
(dB)
Gain
(dB)
-10
-20
-15
IRL
ORL
-40
0
1000
2000
-20
3000
0
Frequency (MHz)
1000
2000
3000
Frequency (MHz)
a. Gain vs. Frequency
b. Input and Output Return Loss vs. Frequency
Fig 26. Gain and Return Loss vs. Frequency
Two-Element Match BGU8007 1.8V
20
0
0
-10
Gain
(dB)
RL
(dB)
-20
-20
IRL
ORL
-40
0
1000
2000
-30
3000
0
Frequency (MHz)
a.
b.
Fig 27. Gain and Return Loss vs. Frequency
Application Note
2000
3000
Frequency (MHz)
Gain vs. Frequency
AN11068
1000
Input and Output Return Loss vs Frequency
Two-Element Match BGU7005 1.8V
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Figures 28 through 31 show the test results for the two-tone and single-tone tests using
the two-element match for both the BGU8007 and BGU7005. The second order
distortion products are reduced compared to the baseline case, but not as much as with
the 3-element jammer immunity match. For instance, the 2nd order harmonic product for
the BGU8007 single-tone test case is measured as -53 dBm compared to -38 dBm for
the baseline.
0
-20
-40
-60
Pout
(dBm)
-80
-100
f1 Fundamental
IM2
-120
-140
-70
-60
-50
-40
-30
-20
-10
0
Pin Single Tone (dBm)
Fig 28. Two Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575.4 MHz)
BGU8007 1.8V
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2-element Match
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
0
-20
-40
-60
Pout
(dBm)
-80
f1 Fundamental
-100
IM2
-120
-140
-70
-60
-50
-40
-30
-20
-10
0
Pin Single Tone (dBm)
Fig 29. Two Tone Test Results (f1 = 787.4 MHz, f2 = 788 MHz, fspur = 1575.4 MHz)
BGU7005 1.8V
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Application Note
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Rev. 2 — 30 May 2012
2-element Match
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Icc
(mA)
16
0
14
-20
12
Pout
(dBm)
10
8
-40
-60
-80
6
-100
4
Fundamental
-120
2
0
2nd Harmonic
-140
-80 -70 -60 -50 -40 -30 -20 -10
0
-70 -60 -50 -40 -30 -20 -10
Pin (dBm)
0
Pin (dBm)
a. Current vs. Pin
b. Pout vs. Pin
Fig 30. Single Tone Test Results f1 = 788 MHz 2-element Match BGU8007 1.8V
0
16
14
-20
12
Icc
(mA)
-40
10
Pout
(dBm)
-60
8
6
-80
4
Fundamental
-100
2
0
-70
-60
-50
-40
-30
-20
-10
0
2nd Harmonic
-120
-70 -60 -50 -40 -30 -20 -10
Pin (dBm)
a. Current vs. Pin
0
Pin (dBm)
b. Pout vs. Pin
Fig 31. Single Tone Test Results f1 = 788 MHz 2-element Match BGU7005 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Figures 32 and 33 show the GNSS-band noise figure for the BGU8007 and BGU7005
with the 2-element compromise input match.
Fig 32. BGU8007 2-element Match 1.8V
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Fig 33. BGU7005 2-element Match 1.8V
5.
Conclusion
By changing the input matching topology of NXP’s GNSS LNAs, the gain of the circuit in
the 700 MHz LTE band can be significantly reduced while leaving the in-band gain nearly
unaltered. This can be accomplished with the addition of one or two low cost, readily
available lumped element components. This has the effect of increasing the immunity to
jamming signals in this band, at the expense of noise figure, which increases slightly due
to having additional components at the input of the device. To further quantify, Tables 7
and 8 below show results for the BGU8007 and BGU7005, respectively, for the case of a
788 MHz jamming signal at a level of -25 dBm at the LNA input. Finally, note that while
the 7th generation BGU7005 and 8th generation BGU8007 are presented here as
examples, these techniques are applicable to the entire family of NXP GNSS LNAs.
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Application Note
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
Table 7.
LTE Band 2nd Harmonic BGU8007
nd
Vcc = 1.8V 2 Order Harmonic Level for Pin = -25 dBm 788 MHz
Matching
Option
Gain
788 MHz
Gain
1576 MHz
Input
Noise Figure*
nd
Referred 2
Harmonic Level
1576 MHz
Baseline
7.7 dB
19.0 dB
-48 dBm
0.75 dB
LTE Jammer
Immunity
-33 dB
19.7 dB
-119 dBm
1.10 dB
Two-Element
Compromise
-4.0 dB
19.2 dB
-61 dBm
1.05 dB
nd
Table 8.
LTE Band 2 Harmonic BGU7005
nd
Vcc = 1.8V 2 Order Harmonic Level for Pin = -25 dBm 788 MHz
Matching
Option
Gain
788 MHz
Gain
1576 MHz
Input
Noise Figure*
nd
Referred 2
Harmonic Level
1576 MHz
Baseline
9.0 dB
16.5 dB
-46 dBm
0.85 dB
LTE Jammer
Immunity
-32 dB
17.4 dB
-122 dBm
1.15 dB
Two-Element
Compromise
-2.4 dB
16.9 dB
-60 dBm
1.15 dB
* Includes board and connector losses, no jammer present
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6. Legal information
6.1 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences
of use of such information.
6.2 Disclaimers
Limited warranty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warranties, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation lost profits, lost savings, business interruption, costs related to the removal
or replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability
towards customer for the products described herein shall be limited in
accordance with the Terms and conditions of commercial sale of NXP
Semiconductors.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liability for inclusion and/or use of
NXP Semiconductors products in such equipment or applications and
therefore such inclusion and/or use is at the customer’s own risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP
Semiconductors accepts no liability for any assistance with applications or
AN11068
Application Note
customer product design. It is customer’s sole responsibility to determine
whether the NXP Semiconductors product is suitable and fit for the
customer’s applications and products planned, as well as for the planned
application and use of customer’s third party customer(s). Customers should
provide appropriate design and operating safeguards to minimize the risks
associated with their applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from national authorities.
Evaluation products — This product is provided on an “as is” and “with all
faults” basis for evaluation purposes only. NXP Semiconductors, its affiliates
and their suppliers expressly disclaim all warranties, whether express,
implied or statutory, including but not limited to the implied warranties of noninfringement, merchantability and fitness for a particular purpose. The entire
risk as to the quality, or arising out of the use or performance, of this product
remains with customer.
In no event shall NXP Semiconductors, its affiliates or their suppliers be
liable to customer for any special, indirect, consequential, punitive or
incidental damages (including without limitation damages for loss of
business, business interruption, loss of use, loss of data or information, and
the like) arising out the use of or inability to use the product, whether or not
based on tort (including negligence), strict liability, breach of contract, breach
of warranty or any other theory, even if advised of the possibility of such
damages.
Notwithstanding any damages that customer might incur for any reason
whatsoever (including without limitation, all damages referenced above and
all direct or general damages), the entire liability of NXP Semiconductors, its
affiliates and their suppliers and customer’s exclusive remedy for all of the
foregoing shall be limited to actual damages incurred by customer based on
reasonable reliance up to the greater of the amount actually paid by
customer for the product or five dollars (US$5.00). The foregoing limitations,
exclusions and disclaimers shall apply to the maximum extent permitted by
applicable law, even if any remedy fails of its essential purpose.
6.3 Trademarks
Notice: All referenced brands, product names, service names and
trademarks are property of their respective owners.
All information provided in this document is subject to legal disclaimers.
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
7. List of figures
Fig 1.
Gain Roll-off Comparison for Baseline and LTE
Jammer Immunity Matching Options ................. 4
BGU8007 1.8V .................................................................... 4
Fig 2.
BGU8007 Baseline Schematic .......................... 5
BGU7005 Baseline Schematic .......................... 6
Fig 3.
BGU8007/BGU7005 Baseline Board Layout..... 7
Fig 4.
a.
Gain vs. Frequency ........................................... 8
Fig 5.
Gain and Return Loss vs. Frequency Baseline
Match BGU8007 ............................................. 8
Gain and Return Loss vs. Frequency
Fig 6.
Baseline Match BGU7005 ................................ 8
Two Tone Test Results (f1 = 787.4 MHz, f2 =
Fig 7.
788 MHz, fspur = 1575.4 MHz) Baseline Match
BGU8007 1.8V .................................................. 9
Two Tone Test Results (f1 = 787.4 MHz, f2 =
Fig 8.
788 MHz, fspur = 1575.4 MHz) Baseline Match
BGU7005 1.8V .............................................. 10
Single Tone Test Results f1 = 788 MHz
Fig 9.
Baseline Match BGU8007 1.8V .................. 11
Single Tone Test Results f1 = 788 MHz
Fig 10.
Baseline Match BGU7005 1.8V ................... 11
Fig 11.
BGU8007 Baseline Match 1.8V ..................... 12
Fig 12.
BGU7005 Baseline Match 1.8V ...................... 13
Fig 13.
BGU8007 LTE Jammer Immunity Match
Schematic ....................................................... 14
BGU7005 LTE Jammer Immunity Match
Fig 14.
Schematic ....................................................... 15
BGU8007/BGU7005 LTE Jammer Immunity
Fig 15.
Board Layout................................................... 16
Gain and Return Loss vs. Frequency LTE
Fig 16.
Jammer Immunity Match BGU8007 1.8V ....... 17
Gain and Return Loss vs. Frequency LTE
Fig 17.
Jammer Immunity Match BGU7005 1.8V ..... 17
Two-Tone Test Results (f1 = 787.4 MHz, f2 =
Fig 18.
788 MHz, fspur = 1575. MHz) LTE Jammer
Immunity Match BGU8007 1.8V .................... 18
Two-Tone Test Results (f1 = 787.4 MHz, f2 =
Fig 19.
788 MHz, fspur = 1575.4 MHz) LTE Jammer
Immunity Match BGU7005 1.8V .................... 19
Single Tone Test Results f1 = 788 MHz LTE
Fig 20.
Jammer Immunity Match BGU8007 1.8V ..... 20
Single Tone Test Results f1 = 788 MHz LTE
Fig 21.
Jammer Immunity Match BGU7005 1.8V ...... 20
BGU8007 LTE Jammer Immunity Match 1.8V
Fig 22.
........................................................................ 21
BGU7005 LTE Jammer Immunity Match 1.8V
Fig 23.
........................................................................ 22
Fig 24.
BGU8007 Two-element Match Schematic ...... 23
Fig 25.
BGU7005 Two-element Match Schematic ...... 24
AN11068
Application Note
Fig 26.
Fig 27.
Fig 28.
Fig 29.
Fig 30.
Fig 31.
Fig 32.
Fig 33.
Gain and Return Loss vs. Frequency TwoElement Match BGU8007 1.8V .....................25
Gain and Return Loss vs. Frequency TwoElement Match BGU7005 1.8V .....................25
Two Tone Test Results (f1 = 787.4 MHz, f2 =
788 MHz, fspur = 1575.4 MHz) 2-element
Match
BGU8007 1.8V ...........................26
Two Tone Test Results (f1 = 787.4 MHz, f2 =
788 MHz, fspur = 1575.4 MHz) 2-element
Match
BGU7005 1.8V ............................27
Single Tone Test Results f1 = 788 MHz 2element Match BGU8007 1.8V .....................28
Single Tone Test Results f1 = 788 MHz 2element Match BGU7005 1.8V .....................28
BGU8007 2-element Match 1.8V ....................29
BGU7005 2-element Match 1.8V ..................30
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 30 May 2012
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
8. List of tables
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
List of Components for Baseline Input Match
BGU8007 .......................................................... 5
List of Components for Baseline Input Match
BGU7005 .......................................................... 6
List of Components for LTE Jammer Immunity
Input Match BGU8007 ................................... 14
List of Components for LTE Jammer Immunity
Input Match BGU7005 ................................... 15
List of Components for Two Element Input
Match BGU8007 ............................................. 23
List of Components for Two Element Input
Match BGU7005 ............................................. 24
LTE Band 2nd Harmonic BGU8007 ................ 31
LTE Band 2nd Harmonic BGU7005 ................. 31
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BGU8007/BGU7005 Matching Options for Improved LTE Jammer Immunity
9. Contents
1.
2.
3.
4.
5.
6.
6.1
6.2
6.3
7.
8.
9.
Introduction ......................................................... 3
Baseline Single Element Match Performance
BGU7005 .............................................................. 4
Input Match for LTE Jammer Immunity ........... 13
Two-element Compromise Input Match........... 22
Conclusion ......................................................... 30
Legal information .............................................. 32
Definitions ........................................................ 32
Disclaimers....................................................... 32
Trademarks ...................................................... 32
List of figures..................................................... 33
List of tables ...................................................... 34
Contents ............................................................. 35
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in the section 'Legal information'.
© NXP B.V. 2012.
All rights reserved.
For more information, visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
Date of release: 30 May 2012
Document identifier: AN11068