NTIA Report 14-506

Effects of Radar Interference on LTE 

(FDD) eNodeB and UE Receiver 

Performance in the 3.5 GHz Band

Geoffrey A. Sanders

John E. Carroll

Frank H. Sanders

Robert L. Sole

U.S. DEPARTMENT OF COMMERCE • National Telecommunications and Information Administration

report series
NTIA Report 14-506

Effects of Radar Interference on LTE 

(FDD) eNodeB and UE Receiver 

Performance in the 3.5 GHz Band

Geoffrey A. Sanders

John E. Carroll

Frank H. Sanders

Robert L. Sole

U.S. DEPARTMENT OF COMMERCE

July 2014

DISCLAIMER

Certain commercial equipment and materials are identified in this report to specify adequately 

the technical aspects of the reported results. In no case does such identification imply 

recommendation or endorsement by the National Telecommunications and Information 

Administration, nor does it imply that the material or equipment identified is the best available 

for this purpose. 

This report only describes the impacts of interference on a prototype 3.5 GHz LTE network at 

the physical layer. In this report, the LTE network is treated as a “black box” and the response of 

a subset of LTE parameters, identified as most-critical by an industry participant working with 

NTIA, are presented. The LTE diagnostic parameters used in this report were recorded by the 

industry participant and were made available to the authors for post-analysis.

iii

CONTENTS

Figures........................................................................................................................................... vii

Tables.............................................................................................................................................xv

Abbreviations/Acronyms and Symbols ....................................................................................... xix

Executive Summary..................................................................................................................... xxi

1 Introduction...................................................................................................................................1

1.1 Interference Coupling Scenario for Possible Future 3.5 GHz Spectrum Sharing .................2

1.2 Implementation of the Interference Scenario in an Interference-Effects Test Bed ...............4

2 Interference-Effects Testing Procedures.......................................................................................7

2.1 LTE Operation During Testing..............................................................................................7

2.2 Radar and Gaussian Noise Interference Waveforms.............................................................7

2.3 Testing Methodology...........................................................................................................10

3 Interference-Effects Test Results................................................................................................12

3.1 Downlink Interference-Effects Results................................................................................12

3.1.1 Continuous Interference Testing ................................................................................12

3.1.2 Burst Interference Testing..........................................................................................40

3.2 Uplink Interference-Effects Results.....................................................................................44

3.2.1 Continuous Interference Testing ................................................................................44

3.2.2 Burst Interference Testing..........................................................................................69

4 LTE Emission Spectrum Measurements.....................................................................................76

4.1 LTE Emission Spectrum Measurement Procedure..............................................................76

4.2 LTE eNB Emission Spectra.................................................................................................77

4.3 LTE UE Emission Spectra...................................................................................................78

5 Summary and Conclusions .........................................................................................................80

5.1 Summary of Work and Results............................................................................................80

5.2 Radar Interference Impacts on LTE UE Receiver Performance (Downlink)......................80

5.2.1 Continuous Interference Impacts................................................................................80

5.2.2 Off-Tuned Continuous Interference Impacts .............................................................81

5.2.3 Burst Interference Impacts .........................................................................................81

5.3 Radar Interference Impacts on LTE eNB Receiver Performance (Uplink).........................81

5.3.1 Continuous Interference Impacts................................................................................81

5.3.2 Burst Interference Impacts .........................................................................................82

5.4 Recommendations for Future Work ....................................................................................82

6 References...................................................................................................................................83

7 Acknowledgements.....................................................................................................................85

Appendix A: LTE Test Bed System Losses ..................................................................................87

v
Appendix B: Comparison Figures of Interference Effects on LTE (TDD) and (FDD) 

Uplinks...........................................................................................................................................89

B.1 Notes on Comparison Figures of Interference Effects on LTE (TDD) and LTE 

(FDD) Uplinks...........................................................................................................................89

B.2 Comparison Figures from the Two LTE Uplinks...............................................................90

vi
FIGURES

Figure 1. Schematic diagram showing coupling scenario between littoral radar 

transmitters and possible future 3.5 GHz LTE systems. By geometry, coupling 

from radar transmitters should occur more into LTE eNB receivers than into UEs........................3

Figure 2. Simple diagram of the test bed for the radar-to-LTE interference 

scenario of Figure 1. ........................................................................................................................4

Figure 3. Detailed diagram of the interference-effects test bed of Figure 2. ...................................5

Figure 4. Data throughput and BLER for 10 MHz wide Gaussian noise 

interference. ...................................................................................................................................14

Figure 5. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, 

DC = 0.1%) interference................................................................................................................15

Figure 6. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, 

DC = 0.1%) interference off-tuned from the LTE eNB center transmit frequency 

by 2 MHz. ......................................................................................................................................16

Figure 7. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, 

DC = 0.1%) interference off-tuned from the LTE eNB center transmit frequency 

by 4 MHz. ......................................................................................................................................17

Figure 8. Data throughput and BLER for P0N-2 (PW = 0.33 μs, PRR = 3,000/sec, 

DC = 0.1%) interference................................................................................................................18

Figure 9. Data throughput and BLER for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, 

DC = 0.1%) interference................................................................................................................19

Figure 10. Data throughput and BLER for P0N-4 (PW = 10 μs, PRR = 1,000/sec, 

DC = 1.0%) interference................................................................................................................20

Figure 11. Data throughput and BLER for P0N-5 (PW = 3.33 μs, PRR = 

3,000/sec, DC = 1%) interference..................................................................................................21

Figure 12. Data throughput and BLER for P0N-6 (PW = 1.0 μs, PRR = 

10,000/sec, DC = 1%) interference................................................................................................22

Figure 13. Data throughput and BLER for P0N-7 (PW = 30 μs, PRR = 1,000/sec, 

DC = 3%) interference...................................................................................................................23

Figure 14. Data throughput and BLER for P0N-8 (PW = 10 μs, PRR = 3,000/sec, 

DC = 3%) interference...................................................................................................................24

Figure 15. Data throughput and BLER for P0N-9 (PW = 3 μs, PRR = 10,000/sec, 

DC = 3%) interference...................................................................................................................25

vii
Figure 16. Data throughput and BLER for P0N-10 (PW = 100 μs, PRR = 

1,000/sec, DC = 10%) interference................................................................................................26

Figure 17. Data throughput and BLER for P0N-11 (PW = 33.3 μs, PRR = 

3,000/sec, DC = 10%) interference................................................................................................27

Figure 18. Data throughput and BLER for P0N-12 (PW = 10 μs, PRR = 

10,000/sec, DC = 10%) interference..............................................................................................28

Figure 19. Data throughput and BLER for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, 

DC = 1%) interference...................................................................................................................29

Figure 20. Data throughput and BLER for Q3N-2 (PW = 1 μs, PRR = 10,000/sec, 

DC = 1.0%) interference................................................................................................................30

Figure 21. Data throughput and BLER for Q3N-3 (PW = 0.33 μs, PRR = 

30,000/sec, DC = 1%) interference................................................................................................31

Figure 22. Data throughput and BLER for Q3N-4 (PW = 10 μs, PRR = 

10,000/sec, equivalent to PW = 100 μs, PRR = 1,000/sec), DC = 10%) 

interference. ...................................................................................................................................32

Figure 23. Data throughput and BLER for Q3N-6 (PW = 3.3 μs, PRR = 

30,303/sec, DC = 10%) interference..............................................................................................33

Figure 24. Data throughput and BLER for Q3N-7 (PW = 10 μs, PRR = 

20,000/sec, equivalent to PW = 200 μs, PRR = 1,000/sec), DC = 20%) 

interference. ...................................................................................................................................34

Figure 25. Data throughput and BLER for Q3N-9 (PW = 6.6 μs, PRR =

30,303/sec, DC = 20%) interference..............................................................................................35

Figure 26. Data throughput and BLER for Q3N-10 (PW = 10 μs, PRR = 

30,000/sec, equivalent to PW = 300 μs, PRR = 1,000/sec), DC = 30%) 

interference. ...................................................................................................................................36

Figure 27. Data throughput and BLER for ECC-1/WFM-1 (PW = 4 μs, PRR = 

1,000/sec, DC = 0.4%) interference...............................................................................................37

Figure 28. Data throughput and BLER for ECC-2/WFM-2 (PW = 100 μs, PRR = 

300/sec, DC = 3%) interference.....................................................................................................38

Figure 29. Data throughput and BLER for P0N-13/TDWR (PW = 1 μs, PRR = 

2,000/sec, DC = 0.05%) interference.............................................................................................39

Figure 30. Data throughput and MCS state for P0N-5 interference (Ipeak = -35 

dBm). .............................................................................................................................................40

viii
Figure 31. Data throughput and MCS state for P0N-8 interference (Ipeak = -35 

dBm). .............................................................................................................................................41

Figure 32. Data throughput and MCS state for P0N-11 interference (Ipeak = -35 

dBm). .............................................................................................................................................41

Figure 33. Data throughput and MCS state for Q3N-1 interference (Ipeak = -30 

dBm). .............................................................................................................................................42

Figure 34. Data throughput and MCS state for Q3N-4 interference (Ipeak = -45 

dBm). .............................................................................................................................................42

Figure 35. Data throughput and MCS state for Q3N-7 interference (Ipeak = -50 

dBm). .............................................................................................................................................43

Figure 36. Data throughput and MCS state for Q3N-10 interference (Ipeak = -50 

dBm). .............................................................................................................................................43

Figure 37. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 10 

MHz wide Gaussian noise interference. ........................................................................................45

Figure 38. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) interference. ..................................................46

Figure 39. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-2 (PW = 0.33 μs, PRR = 3,000/sec, DC = 0.1%) interference. .............................................47

Figure 40. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) interference. .............................................48

Figure 41. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-4 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) interference. ...................................................49

Figure 42. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) interference. ................................................50

Figure 43. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-6 (PW = 1 μs, PRR = 10,000/sec, DC = 1%) interference. ...................................................51

Figure 44. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) interference. ...................................................52

Figure 45. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) interference. ...................................................53

Figure 46. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) interference. ...................................................54

ix
Figure 47. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) interference. .............................................55

Figure 48. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) interference. ............................................56

Figure 49. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) interference. .............................................57

Figure 50. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) interference. ..................................................58

Figure 51. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-2 (PW = 0.33 μs, PRR = 10,000/sec, DC = 1%) interference. .............................................59

Figure 52. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) interference. .............................................60

Figure 53. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to PW = 100 μs, PRR = 

1,000/sec, DC = 10%) interference................................................................................................61

Figure 54. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) interference. .............................................62

Figure 55. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to PW = 200 μs, PRR = 

1,000/sec, DC = 20%) interference................................................................................................63

Figure 56. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) interference. .............................................64

Figure 57. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent to PW = 300 μs, PRR = 

1,000/sec, DC = 30%) interference................................................................................................65

Figure 58. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 0.4%) interference. ...................................66

Figure 59. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 3%) interference. .....................................67

Figure 60. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 

TDWR/P0N-13 (PW = 1 μs, PRR = 2,000/sec, DC = 3%) interference. ......................................68

Figure 61. Data throughput and MCS state for P0N-1 interference. .............................................69

Figure 62. Data throughput and MCS state for P0N-2 interference. .............................................70

x
Figure 63. Data throughput and MCS state for P0N-5 interference. .............................................70

Figure 64. Data throughput and MCS state for P0N-8 interference. .............................................71

Figure 65. Data throughput and MCS state for P0N-10 interference. ...........................................71

Figure 66. Data throughput and MCS state for P0N-11 interference. ...........................................72

Figure 67. Data throughput and MCS state for Q3N-1 interference..............................................72

Figure 68. Data throughput and MCS state for Q3N-4 interference..............................................73

Figure 69. Data throughput and MCS state for Q3N-6 interference..............................................73

Figure 70. Data throughput and MCS state for Q3N-7 interference..............................................74

Figure 71. Data throughput and MCS state for Q3N-9 interference..............................................74

Figure 72. Data throughput and MCS state for Q3N-10 interference............................................75

Figure 73. System set-up for the LTE emission spectra measurements. .......................................76

Figure 74. Peak-detected and average-detected LTE eNB emission spectra.................................77

Figure 75. Roll-off of LTE eNB emission spectrum. ....................................................................78

Figure 76. Peak-detected and average-detected LTE UE emission spectra...................................79

Figure A–1. Block diagram of the LTE network showing all the components in 

the RF path, interference injection points, and spectrum analyzer monitoring 

points..............................................................................................................................................88

Figure B–1. Throughput and eNB Noise Floor for LTE (TDD) network for 20 

MHz wide Gaussian noise interference (covering full LTE bandwidth).......................................90

Figure B–2. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network 

for 10 MHz wide Gaussian noise interference (covering full LTE bandwidth). ...........................90

Figure B–3. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-1 

interference. ...................................................................................................................................91

Figure B–4. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network 

for P0N-1 interference. ..................................................................................................................91

Figure B–5. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-2 

interference. ...................................................................................................................................92

Figure B–6. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network 

for P0N-2 interference. ..................................................................................................................92

xi
Figure B–7. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-3 

interference. ...................................................................................................................................93

Figure B–8. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network 

for P0N-3 interference. ..................................................................................................................93

Figure B–9. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-4 

interference. ...................................................................................................................................94

Figure B–10. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-4 interference. ....................................................................................................94

Figure B–11. Throughput and eNB Noise Floor for LTE (TDD) network for P0N5 interference. ................................................................................................................................95

Figure B–12. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-5 interference. ....................................................................................................95

Figure B–13. Throughput and eNB Noise Floor for LTE (TDD) network for P0N6 interference. ................................................................................................................................96

Figure B–14. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-6 interference. ....................................................................................................96

Figure B–15. Throughput and eNB Noise Floor for LTE (TDD) network for P0N7 interference. ................................................................................................................................97

Figure B–16. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-7 interference. ....................................................................................................97

Figure B–17. Throughput and eNB Noise Floor for LTE (TDD) network for P0N8 interference. ................................................................................................................................98

Figure B–18. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-8 interference. ....................................................................................................98

Figure B–19. Throughput and eNB Noise Floor for LTE (TDD) network for P0N9 interference. ................................................................................................................................99

Figure B–20. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-9 interference. ....................................................................................................99

Figure B–21. Throughput and eNB Noise Floor for LTE (TDD) network for P0N10 interference. ............................................................................................................................100

Figure B–22. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-10 interference. ................................................................................................100

xii
Figure B–23. Throughput and eNB Noise Floor for LTE (TDD) network for P0N11 interference. ............................................................................................................................101

Figure B–24. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-11 interference. ................................................................................................101

Figure B–25. Throughput and eNB Noise Floor for LTE (TDD) network for P0N12 interference. ............................................................................................................................102

Figure B–26. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-12 interference. ................................................................................................102

Figure B–27. Throughput and eNB Noise Floor for LTE (TDD) network for P0N13/TDWR interference.................................................................................................................103

Figure B–28. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for P0N-13/TDWR interference. ...................................................................................103

Figure B–29. Throughput and eNB Noise Floor for LTE (TDD) network for ECC1/WFM-1 interference. ................................................................................................................104

Figure B–30. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for ECC-1/WFM-1 interference.....................................................................................104

Figure B–31. Throughput and eNB Noise Floor for LTE (TDD) network for ECC2/WFM-2 interference. ................................................................................................................105

Figure B–32. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for ECC-2/WFM-2 interference.....................................................................................105

Figure B–33. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N1 interference. ..............................................................................................................................106

Figure B–34. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-1 interference...................................................................................................106

Figure B–35. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N2 interference. ..............................................................................................................................107

Figure B–36. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-2 interference...................................................................................................107

Figure B–37. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N3 interference. ..............................................................................................................................108

Figure B–38. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-3 interference...................................................................................................108

xiii
Figure B–39. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N5 interference. ..............................................................................................................................109

Figure B–40. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-4 interference (Q3N-4 waveform parameters are the same as 

Q3N-5 in previous study).............................................................................................................109

Figure B–41. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N6 interference. ..............................................................................................................................110

Figure B–42. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-6 interference...................................................................................................110

Figure B–43. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N9 interference. ..............................................................................................................................111

Figure B–44. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-9 interference...................................................................................................111

Figure B–45. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N12 interference. ............................................................................................................................112

Figure B–46. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) 

network for Q3N-10 interference (Q3N-10 waveform parameters are the same as 

Q3N-12 in previous study)...........................................................................................................112

xiv
TABLES

Table 1. P0N (carrier wave) pulsed radar waveform parameters. ...................................................8

Table 2. Q3N (swept-frequency) pulsed radar waveform parameters, 1 MHz/μs 

chirp. ................................................................................................................................................8

Table 3. Additional special interference waveforms used in testing. ..............................................9

Table 4. Relationship between MCS, CQI, modulation, and spectral efficiency. .........................13

Table 5. MCS state for 10 MHz wide Gaussian noise interference...............................................14

Table 6. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) 

interference. ...................................................................................................................................15

Table 7. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) 

interference off-tuned from the LTE eNB center transmit frequency by 2 MHz. .........................16

Table 8. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) 

interference off-tuned from the LTE eNB center transmit frequency by 4 MHz. .........................17

Table 9. MCS state for P0N-2 (PW = 0.33 μs, PRR = 3000/sec, DC = 0.1%) 

interference. ...................................................................................................................................18

Table 10. MCS state for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) 

interference. ...................................................................................................................................19

Table 11. MCS state for P0N-4 (PW = 10 μs, PRR = 1000/sec, DC = 1.0%) 

interference. ...................................................................................................................................20

Table 12. MCS state for P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) 

interference. ...................................................................................................................................21

Table 13. MCS state for P0N-6 (PW = 1.0 μs, PRR = 10,000/sec, DC = 1%) 

interference. ...................................................................................................................................22

Table 14. MCS state for P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) 

interference. ...................................................................................................................................23

Table 15. MCS state for P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) 

interference. ...................................................................................................................................24

Table 16. MCS state for P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) 

interference. ...................................................................................................................................25

Table 17. MCS state for P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) 

interference. ...................................................................................................................................26

xv
Table 18. MCS state for P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) 

interference. ...................................................................................................................................27

Table 19. MCS state for P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) 

interference. ...................................................................................................................................28

Table 20. MCS State for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) 

interference. ...................................................................................................................................29

Table 21. MCS state for Q3N-2 (PW = 1 μs, PRR = 10,000/sec, DC = 1.0%) 

interference. ...................................................................................................................................30

Table 22. MCS state for Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) 

interference. ...................................................................................................................................31

Table 23. MCS state for Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to 

PW = 100 μs, PRR = 1,000/sec), DC = 10%) interference. ..........................................................32

Table 24. MCS state for Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) 

interference. ...................................................................................................................................33

Table 25. MCS state for Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to 

PW = 200 μs, PRR = 1,000/sec), DC = 20%) interference. ..........................................................34

Table 26. MCS state for Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) 

interference. ...................................................................................................................................35

Table 27. MCS state for Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent to 

PW = 300 μs, PRR = 1,000/sec), DC = 30%) interference. ..........................................................36

Table 28. MCS state for ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 

0.4%) interference..........................................................................................................................37

Table 29. MCS state for ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 

3%) interference.............................................................................................................................38

Table 30. MCS state for P0N-13/TDWR (PW = 1 μs, PRR = 2,000/sec, DC = 

0.05%) interference........................................................................................................................39

Table 31. MCS state for 10 MHz wide Gaussian noise interference.............................................45

Table 32. MCS state for P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) 

interference. ...................................................................................................................................46

Table 33. MCS state for P0N-2 (PW = 0.33 μs, PRR = 3,000/sec, DC = 0.1%) 

interference. ...................................................................................................................................47

Table 34. MCS state for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) 

interference. ...................................................................................................................................48

xvi
Table 35. MCS state for P0N-4 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) 

interference. ...................................................................................................................................49

Table 36. MCS state for P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) 

interference. ...................................................................................................................................50

Table 37. MCS state for P0N-6 (PW = 1 μs, PRR = 10,000/sec, DC = 1%) 

interference. ...................................................................................................................................51

Table 38. MCS state for P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) 

interference. ...................................................................................................................................52

Table 39. MCS state for P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) 

interference. ...................................................................................................................................53

Table 40. MCS state for P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) 

interference. ...................................................................................................................................54

Table 41. MCS state for P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) 

interference. ...................................................................................................................................55

Table 42. MCS state for P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) 

interference. ...................................................................................................................................56

Table 43. MCS state for P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) 

interference. ...................................................................................................................................57

Table 44. MCS state for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) 

interference. ...................................................................................................................................58

Table 45. MCS state for Q3N-2 (PW = 0.33 μs, PRR = 10,000/sec, DC = 1%) 

interference. ...................................................................................................................................59

Table 46. MCS state for Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) 

interference. ...................................................................................................................................60

Table 47. MCS state for Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to 

PW = 100 μs, PRR = 1,000/sec), DC = 10%) interference. ..........................................................61

Table 48. MCS state for Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) 

interference. ...................................................................................................................................62

Table 49. MCS state for Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to 

PW = 200 μs, PRR = 1,000/sec, DC = 20%) interference.............................................................63

Table 50. MCS state for Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) 

interference. ...................................................................................................................................64

xvii
Table 51. MCS state for Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent to 

PW = 300 μs, PRR = 1,000/sec, DC = 30%) interference.............................................................65

Table 52. MCS state for ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 

0.4%) interference..........................................................................................................................66

Table 53. MCS state for ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 

3%) interference.............................................................................................................................67

Table 54. MCS state for TDWR/P0N-13 (PW = 1 μs, PRR = 2,000/sec, DC = 3%) 

interference. ...................................................................................................................................68

xviii
ABBREVIATIONS/ACRONYMS AND SYMBOLS

BLER block error rate

CQI Channel quality indicator

CSV comma separated variable

DC duty cycle

EIRP effective isotropic radiated power

eNB E-UTRAN Node B or Evolved Node B

FCC Federal Communications Commission

FDD frequency division duplexing

FDR frequency dependent rejection

FNPRM Further Notice of Proposed Rulemaking

GHz Gigahertz

HARQ hybrid automatic repeat request

I interference power

ITS Institute for Telecommunication Sciences (NTIA)

kHz kilohertz

LNA low noise amplifier

LTE Long Term Evolution

MCS modulation coding scheme

MHz Megahertz

MIMO multiple input multiple output

ms milliseconds

N noise power

nmi nautical miles

NPRM Notice of Proposed Rulemaking

xix
NTIA National Telecommunications and Information Administration

OOB out of band

OSM Office of Spectrum Management

P0N fixed-frequency carrier wave pulse modulation

PW pulse width

PRR pulse repetition rate

Q3N swept-frequency carrier wave pulse modulation

RB resource block

RF radio frequency

RLM radio link monitoring

RSSI received signal strength indicator

S LTE received signal power

TDD time division duplexing

TDWR Terminal Doppler Weather Radar

UE user equipment

VSG vector signal generator

xx
EXECUTIVE SUMMARY

In late 2012, the Federal Communications Commission (FCC) issued a Notice of 

Proposed Rulemaking (NPRM) in FCC Docket 12-354 [1], followed by a Further Notice 

of Proposed Rulemaking (FNPRM) [2] in April 2014, regarding possible future spectrum 

sharing between radar and non-radar systems in the band 3550–3650 MHz (3.5 GHz). 

These documents called for tests and measurements to investigate the compatibility of 

broadband communications systems and incumbent Federal radars operating in that band. 

In response, personnel from the National Telecommunications and Information 

Administration (NTIA)’s Office of Spectrum Management (OSM) and NTIA’s Institute 

for Telecommunication Sciences (ITS) have performed interference-effects tests in which 

simulated radar signals were injected into a prototype 4G Long Term Evolution (LTE) 

Frequency Division Duplexing (FDD) network that operates in the 3.5 GHz band.

Prototype LTE units, provided by an industry participant, for the 3.5 GHz band were used 

during these tests as no commercially available hardware existed at the time of the 

testing. Being prototypes, the tested LTE units used prototype RF front-end hardware 

with a nominal 7 dB receiver noise figure. These tests did not investigate high-power 

effects such as LTE receiver saturation or front-end overload. Interference power levels 

as high as -25 dBm were injected into the radio RF front-ends.

The industry participant configured a laboratory LTE network for the tests and 

maintained it as an actual deployment during all phases of testing. The testing was done 

via hardline RF connections that were free of any external RF sources that could possibly 

affect the test results.

Twenty-four interference waveforms were injected into both the uplink and downlink paths of 

the prototype LTE network; the tests were performed in a closed-loop test bed under steady-state 

conditions and the interference was synthesized using up to two vector signal generators (VSGs)

at a time. The interference injection was done separately on either the uplink or the downlink RF 

path. Diagnostic LTE system software, running in the background, collected performance data.

The desired downlink signal power was held at a constant level throughout the tests, set to a 

nominal level by the LTE engineers who assisted the testing. The desired uplink signal power 

was set to a nominal starting level and verified before each new interference waveform data 

collection. The uplink signal level varied during the tests due to power control, which is part of 

normal LTE operation, and could increase power by as much as 25 dB from the nominal starting 

point. 

For the downlink tests, data throughput, block error rate (BLER) of the first hybrid automatic 

repeat request (HARQ) transmission, and modulation coding scheme (MCS) were recorded for 

post-test analysis. For the uplink tests, UE transmit signal power, MCS, BLER of the first 

transmission of HARQ, and resource block (RB) usage were recorded as a function of 

interference power level. Nominal rates of data throughput were 48 Mbps and 12 Mbps for the 

downlink and uplink, respectively. Call initiation and hand-off performance were not tested. 

Each interference waveform was specified by pulse modulation, pulse width, and pulse repetition 

rate. Pulse modulation for each waveform was either simple pulsing of a fixed-frequency carrier 

xxi
wave (referred to as P0N) or else swept-frequency for the duration of each pulse (called chirping

or Q3N). The radar waveforms were not exact replications of any existing or planned future 

operational 3.5 GHz radar emissions. By not exactly replicating any operational or possible 

future radar waveforms, the authors avoided issues with association, classification and 

identification of particular waveforms with individual radar systems. This approach also made 

the test results applicable to radar interference effects on LTE receivers on a general rather than 

system-specific basis. The radar interference waveform parameters were carefully tailored to 

span the entire range of all existing and anticipated future waveforms that do/may occur in the

3.5 GHz spectrum. A band-limited Gaussian noise waveform was included along with two 

waveforms from a test that was previously performed by the European CEPT Electronic 

Communications Committee (ECC). A waveform that replicated a widely deployed type of 

weather radar which operates in the band 5600–5650 MHz was also tested.

Two interference scenarios were tested: continuous and burst. Continuous pulse interference 

testing allowed prolonged collection of LTE system performance statistics. However, in realworld situations, radar beams do not often dwell on fixed points in space, producing continuous 

pulse streams at individual locations. Rather, radar beams ordinarily scan rapidly across points in 

space. This means that receivers ordinarily see radar interference as short, intermittent bursts of 

pulses. In this study, such short, intermittent bursts were injected into the LTE network to 

replicate the way that deployed LTE networks would typically encounter radar interference. 

For continuous-interference tests, the waveforms were injected at steady-state power levels 

during nominal 60 second intervals of data collection. The injected power for each interference 

waveform started at a low level and was increased in discrete steps until reaching a point where 

the throughput decreased to 0 Mbps or until the VSG power maxed out at the limit of permissible 

power into the LTE network. The impacts of the waveforms on the respective receiver’s 

performance parameters were processed to produce graphs showing the impact that each 

waveform had on the receiver’s performance as a function of the received interference power 

level.

For burst interference tests, selected interference waveforms were injected in 20 pulse bursts 

spaced 5 seconds apart, thus replicating the behavior typical of radar beam scanning. Interference 

power levels as high as -25 dBm were injected while data throughput and MCS were monitored. 

For the continuous-interference downlink case, all P0N interference waveforms produced 

appreciable effects on data throughput when interference, I, was greater than -65 dBm. Some 

Q3N waveforms degraded data throughput when interference, I, was -85 dBm. As the 

interference power level was increased, the interference impact increased.

For the continuous-interference uplink case, at least one of the four measured parameters 

(throughput, UE transmit power, BLER, and RB usage) were affected by increasing interference 

power. It is believed that since the UE was able to vary transmit power and RB usage, the uplink 

was more adaptable to interference than the downlink.

Concerning the results of burst testing, at the highest interference power levels (I between -50 

dBm and -30 dBm), downlink data throughput rates were minimally affected for all tested burst 

interference waveforms. The effect is observed as momentary, evenly-spaced (every 5 seconds) 

xxii
reductions in throughput. The Q3N-4 (10% duty cycle) waveform had the greatest impact,

producing momentary reductions of up to 7 Mbps (from 48 Mbps to 41 Mbps). There were no 

discernable impacts on uplink data throughput rates.

The authors do not determine the acceptability of radar interference effects on LTE network 

performance. The data in this report can be used as a building block in the construction of band 

sharing criteria for radar transmitters and LTE receivers, supporting possible future spectrum 

sharing at 3.5 GHz.

More work is needed in this area to support sharing in the 3.5 GHz band. Topics for additional 

testing could include: these same types of tests with commercially available 3.5 GHz LTE 

receivers, an investigation of LTE receiver saturation and gain compressions due to pulsed 

signals, investigation of interference into an LTE network with multiple user equipment devices, 

and measuring the emissions of additional 3.5 GHz LTE transmitters. NTIA is prepared to work 

with other government agencies and industry to accomplish these goals.

xxiii
EFFECTS OF RADAR INTERFERENCE ON LTE (FDD) ENODEB AND UE 

RECEIVER PERFORMANCE IN THE 3.5 GHZ BAND

Geoffrey A. Sanders,

1 John E. Carroll,1 Frank H. Sanders,1 Robert L. Sole2

In response to proposals to introduce new radio systems into 3.5 GHz radio 

spectrum in the United States, the authors have performed measurements and 

analysis on effects of interference, from a variety of radar waveforms, to the 

performance of a prototype 3.5 GHz Long Term Evolution (LTE) network, 

consisting of one base station (an eNodeB) and one client (referred to as user 

equipment or UE) utilizing frequency-division duplexing (FDD). This work has 

been prompted by the possibility that LTE receivers may eventually share 

spectrum with radar operations in this spectrum range. Radar pulse parameters 

used in this testing spanned the range of both existing and anticipated future radar 

systems in the 3.5 GHz spectrum range. Effects of radar interference on the LTE 

uplink and downlink throughput, block error rate (BLER), and modulation coding 

scheme (MCS) were measured. Additionally, for the uplink tests, resource block 

(RB) usage and UE transmit power were recorded. Effects on LTE performance 

are presented as a function of radar pulse parameters and the incident power level 

of radar pulses into the LTE receivers. The authors do not determine the 

interference protection criterion for LTE networks. Rather, the data presented can 

be used by spectrum managers and engineers as a building block in the

construction of band sharing criteria for radar transmitters and LTE receivers, 

supporting possible future spectrum sharing at 3.5 GHz.

Key words: Block error rate (BLER); chirped pulses; Long Term Evolution (LTE); P0N pulses;

radar; spectrum sharing; frequency-division duplexing (FDD); evolved-Node B 

(eNB); Q3N pulses

1 INTRODUCTION

In December of 2012, the Federal Communications Commission (FCC) issued a Notice 

of Proposed Rulemaking (NPRM) [1] followed by a Further Notice of Proposed 

Rulemaking (FNPRM) [2] in April of 2014, regarding possible future spectrum sharing 

between radar and non-radar systems in radio spectrum near 3.5 GHz. In response to this 

NPRM and FNPRM, personnel from NTIA’s Office of Spectrum Management (OSM) 

and NTIA’s Institute for Telecommunication Sciences (ITS) have performed 

interference-effects tests in which simulated radar signals were injected into a prototype 

Long Term Evolution (LTE) frequency-division duplexing (FDD) network, operating in 

1 The authors are with the Institute for Telecommunication Sciences, National Telecommunications and 

Information Administration (NTIA), U.S. Dept. of Commerce, Boulder, CO 80305.

2 The author is with the Office of Spectrum Management, NTIA, U.S. Dept. of Commerce, Washington, 

DC 20230.

 
the 3.5 GHz frequency band. Interference was injected into both the base station, known 

as an eNodeB (eNB) in LTE networks, and a single client, called user equipment (UE) 

The interference was injected into the uplink (UE to eNB) and downlink (eNB to UE) RF 

paths separately.3 The eNB transmitter operated with 9 MHz of bandwidth centered at 

3600 MHz and the UE transmitter operated with up to 7.2 MHz of bandwidth centered at 

3520.9 MHz.

A prototype micro-cell LTE system was used in the NTIA tests described in this report. 

Current plans for LTE operations at 3.5 GHz in the United States envision the use of 

micro-cell LTE systems, as described in [1]. The authors have performed similar testing 

on a macro-cell network as described in [3]. The differences between micro and macrocell LTE systems are understood to be primarily in eNB antenna types, heights, and gains 

along with transmitter power levels. Error correction and other signal processing 

parameters inherent to the LTE protocol are understood to be identical between the two 

types of systems.

The tests described in this report were performed in March 2014 at an industry laboratory 

in Colorado. The effects of radar interference on data throughput, block error rate 

(BLER) of the first hybrid automatic repeat request (HARQ) transmission (hereafter 

referred to as just BLER), and modulation coding scheme (MCS) were observed and 

recorded for both uplink and downlink. Additionally, the effects of radar interference on 

UE transmit power and UE resource block (RB) usage were observed and recorded for 

the uplink tests. The test results, and the measurements that produced them, are described 

in this report.

The authors do not determine the interference protection criterion for nominal LTE 

network performance. Rather, the data presented in this report can be used by spectrum 

managers and engineers as a building block in the construction of band sharing criteria

for radar transmitters and LTE receivers, supporting possible future spectrum sharing at 

3.5 GHz.

1.1 Interference Coupling Scenario for Possible Future 3.5 GHz Spectrum Sharing 

3.5 GHz spectrum is utilized by a variety of radar systems [4]. Many of these radars operate on 

ships in near-shore (littoral) waters around American coastlines. These radars are used for a 

variety of purposes and missions including air surveillance and air defense. Transmitted beams

of these radars scan through 360 degrees of azimuth around their ship platforms, providing 

detection, surveillance and tracking of air-breathing aerial targets at distances of up to about 

180–240 nautical miles (nmi) and of targets outside the Earth’s atmosphere at larger distances. 

These radar beams transmit over both oceans and littoral shorelines. The air-search radar beam 

shapes often have cross sections in the shape of a 1/(squared cosecant) function. The lower edge 

of the radars’ air-search and space-search beam is typically tilted above any given ship’s local 

3 The interference was injected separately to isolate interference effects in the respective paths. In the real 

world, it is unlikely that uplinks and downlinks would experience interference simultaneously (i.e. it is 

unlikely that they would be co-linear with a radar beam).

2

 
horizon at an angle of about 0.5 to 1.0 angular degrees. Additional information about radar 

systems operating in the 3100–3650 MHz frequency band is presented in [4].

Traditional (legacy) long range air-search radar waveforms often use pulse widths (PWs) that are 

between 1 and 10 μs long, at pulse repetition rates (PRRs) of between 300 and 1,000 pulses/sec. 

The transmitted waveform duty cycle (DC, defined as time interval during which waveform 

power is transmitted divided by total time of the waveform’s periodicity) of such radars is about 

0.1 percent. Such radars use tube-type output devices (e.g., magnetrons, klystrons, crossed-field 

amplifiers) that generate effective isotropic radiated peak power levels (peak EIRP) of 1–10 GW. 

Newer radars often use solid-state output devices radiating peak EIRPs of 10–100 MW, but at 

the cost of longer PWs and higher DCs that can approach 10 percent.

4 The longer PWs of current 

and future solid state radars require, in turn, that transmitted pulses be frequency-modulated or 

phase coded to maintain adequate range resolution. The NTIA radar interference waveforms

incorporate the characteristics of both legacy and newer radars.

Future LTE systems at 3.5 GHz are expected to operate with handheld user equipment (UE) units 

that will usually be at or near ground level. The UEs are expected to communicate with LTE 

eNBs that will typically be located at greater heights than the UEs, for example on the sides of 

buildings or on building rooftops. Because antenna beams for the radar systems of concern are 

tilted somewhat above local horizons, they should couple more strongly into LTE systems’ eNB

receivers than into the UE receivers. This coupling scenario is shown schematically in Figure 1.

Although it is believed that radar interference would couple into LTE eNB receivers more 

strongly than into UE receivers, effects on both the uplink and downlink were examined in this 

study. To maximize coverage, LTE eNB antennas are typically situated at high locations such as 

at the tops of towers or building rooftops and, therefore, have a higher probability of receiving 

radar interference.

Figure 1. Schematic diagram showing coupling scenario between littoral radar transmitters and 

possible future 3.5 GHz LTE systems. By geometry, coupling from radar transmitters should 

occur more into LTE eNB receivers than into UEs.

4 Solid-state radars can cause more interference than higher-power tube-transmitter radars because the 

peak EIRPs of the newer radars are still high enough to exceed interference thresholds for many systems, 

while their higher DCs of around 10 percent have more impact in the time domain than the 0.1 percent 

DCs of older radars.

3

 
1.2 Implementation of the Interference Scenario in an Interference-Effects Test Bed

The authors assembled a hardware implementation of the coupling scenarios of Figure 1 in a test 

bed with the assistance of an industry participant. This included an LTE UE, an LTE eNB, and a 

transmitter producing radar interference waveforms consisting of one or two vector signal 

generators (VSGs) for the uplink and downlink cases, respectively. This implementation is 

shown schematically in Figure 2 and as a more electronically-detailed diagram in Figure 3. A full 

description of the losses in the test bed LTE network is provided in Appendix A.

For the uplink tests, radar interference was injected into the receiver side of the LTE eNB along 

with desired LTE signals originating from an LTE UE. To do this, and to establish and maintain 

normal LTE communications during the testing, a link had to be established for regular, two-way 

communications between the eNB and UE.

5 In the LTE eNB receiver path, a radio frequency 

(RF) combiner was installed to couple radar signals into the eNB receiver along with the desired 

UE signals. This combiner requirement is shown in Figures 2 and 3.

For the downlink tests, radar interference was injected into the UE receiver on both transmit 

channels using two separate VSGs along with LTE traffic from the LTE eNB. Once again a 

regular two-way communication link between the eNB and UE was established while the 

interference was injected. This configuration is also shown in Figures 2 and 3.

Figure 2. Simple diagram of the test bed for the radar-to-LTE interference scenario of Figure 1.

5 It is noted that there could be utility in eventually testing an LTE eNB with multiple UE inputs.

4

 
Figure 3. Detailed diagram of the interference-effects test bed of Figure 2.

The effects of interference were determined by observing and recording diagnostic outputs from 

either the LTE eNB receiver or the LTE UE receiver whilst radar interference was injected. The 

interference effects were measured as functions of the power levels and waveform modulations 

of the radar interference. The measured diagnostic parameters for the downlink case were data 

throughput, BLER, and MCS usage. For the uplink case, UE transmit power and RB usage were 

recorded in addition to the parameters recorded for the downlink case. 

All RF connections within the test bed were via hardlines; the LTE communication signal and

the radar interference were not radiated. Hardlines were used so that the effects of radar 

interference could be observed without any effects from radio propagation, antenna performance, 

environmental noise or extraneous signals from other radio systems. While such collateral

factors might well affect actual 3.5 GHz spectrum sharing, the purpose of this study was to 

understand the effects of radar interference alone; a hardline test bed was deemed to be the best 

approach for observing radar interference effects with a high degree of isolation and acuity. 

Propagation studies and analysis will eventually be needed to determine the exact power levels 

that would be coupled from radar transmitters to LTE receivers at actual field locations under a 

variety of ambient conditions and circumstances, as discussed in [4]. LTE performance 

degradation that might arise from additional factors associated with radiated signal environments

should likewise be studied separately.

5
The authors programmed two Agilent 8267 (C and D variants) VSGs to generate radar 

interference waveforms in addition to a 10 MHz wide Gaussian noise waveform. The 

interference waveforms are described in detail in Section 2. 

For the downlink case, two VSGs were required for the Gaussian noise tests to remove any 

signal correlation. Each VSG was programmed with a unique 10 MHz wide Gaussian noise 

signal and each was combined with one of the eNB transmit channels as shown in Figure 3.

6

While two VSGs were not required for the radar waveform interference injection, it was decided 

to continue using two for consistency. The radar waveforms transmitted by the two VSGs were 

synchronized using an Agilent 33250 arbitrary waveform generator outputting a trigger pulse to 

each of the two VSGs. Power levels from each VSG were calibrated at the beginning of each 

interference waveform test to be the same level on both receive channel paths and the VSGs’ 

time sources were synchronized via a 10 MHz reference signal.

For the uplink case, only a single VSG was required as there was only one interference injection 

coupler. This is consistent with the understood operation of an LTE UE at the time these tests 

were conducted, where there is typically only one data stream transmitted from the UE. In future 

LTE implementations the UE will support multiple transmitters. It is believed this will make an 

LTE network more robust to interference. 

6 Originally a single VSG was used to inject the Gaussian noise signal into both channels via a splitter. 

The LTE network was able to use the correlated nature of the split Gaussian noise signal received at the 

UE to cancel it out to some extent, thereby significantly reducing the effects of the interference. The 

authors, along with engineers from the industry participant, decided that in a real world situation, a 

Gaussian noise signal received at the UE would be uncorrelated so it was decided to use two separate 

VSGs loaded with distinct Gaussian noise waveforms.

6

 
2 INTERFERENCE-EFFECTS TESTING PROCEDURES

2.1 LTE Operation During Testing

As shown in Figures 2 and 3, the UE and eNB units operated with traffic generators and 

communicated via hardline connection. The UE and eNB operated with frequency diversity and 

80 MHz of separation between uplink and downlink channels. The eNB communicated with the 

UE using two MIMO channels across 9 MHz (50 RBs, each 180 kHz wide) of bandwidth,

centered at 3600 MHz. The UE communicated with the eNB using a single channel centered at 

3520.9 MHz, using a nominal 40 RBs. Path loss in both uplink and downlink directions was 

simulated via adjustable attenuators in the RF path to values recommended by the industry 

participant as being within nominal coverage. The attenuators in the uplink RF path were set 

such that the signal power level from the UE into the eNB receiver was -85 dBm without 

interference. Conversely, the attenuators in the downlink RF path were set such that the signal 

power level from the eNB into the UE receiver was -75 dBm without interference. LTE receiver

performance for the eNB and the UE (data throughput, BLER,

7 MCS, UE transmit power,8 and 

RBs) was monitored by diagnostic software throughout the testing. The nominal throughput was 

approximately 48 Mbps in the downlink and approximately 12 Mbps in the uplink as configured 

by the industry participant.

2.2 Radar and Gaussian Noise Interference Waveforms

The interference effects of twenty-three radar waveforms and a 10 MHz wide Gaussian noise

signal were tested. Each radar waveform was pulsed and was specified by modulation, pulse 

width (PW), and pulse repetition rate (PRR). Radar pulses were modulated as either fixedfrequency carrier waves (designated P0N) or as linearly increasing swept-frequency carriers

(called chirping, designated Q3N).

9 The radar waveforms were not exact replications of any 

existing or planned future operational 3.5 GHz radar emissions. By not exactly replicating any 

operational or possible future radar waveforms, the authors avoided issues of identification of 

waveforms with operational radar systems. This approach was also intended to make the test 

results applicable to radar interference effects on LTE receivers on a generic rather than a 

system-specific basis. The radar interference waveform parameter space was designed, however,

to span the entire range of all existing and possible future radar waveforms that do/may occur in

3.5 GHz band. Emission spectra of the interference waveforms tested are provided in Appendix 

B of [3].

7 BLER is defined as the number of erroneous transport data block transmissions divided by the total 

number of transport data block transmissions.

8 The UE was configured by the industry participant to have a maximum possible transmit power of -10 

dBm.

9 P0N and Q3N designations are used to identify these modulations in the NTIA Manual of Regulations 

and Procedures for Federal Radio Frequency Management (the NTIA “Redbook”), Section 9.8.2. 

http://www.ntia.doc.gov/page/2011/manual-regulations-and-procedures-federal-radio-frequencymanagement-redbook

7

 
A Gaussian noise waveform, of 10 MHz bandwidth, was programmed and used in the testing. 

The Gaussian noise testing provided a baseline check on the results of the radar interference 

testing. The authors estimated, in advance of the testing, that Gaussian noise testing should 

verify that the LTE test bed system would yield interference effects even if some or none of

radar waveforms were to produce identifiable interference effects.

The technical characteristics of the radar interference waveforms are shown for P0N and Q3N 

pulse modulations in Tables 1 and 2, respectively. Each entry includes a code printed in red by 

which each waveform was identified in the VSG’s on-board memory; these codes were used in 

the field-data logs to identify each waveform as testing progressed. The programmed 

interference waveforms included a 10 MHz wide Gaussian noise waveform described above, 

plus a waveform similar to that of a terminal Doppler weather radar (TDWR) and two 

waveforms (designated ECC-1 and -2) that were used in similar previous interference testing in 

Europe [5].

Table 1. P0N (carrier wave) pulsed radar waveform parameters.

Duty Cycle (percent) PRR = 1,000/sec PRR = 3,000/sec PRR = 10,000/sec

0.1 PW = 1 μs

P0N-1

PW = 0.33 μs

P0N-2

PW = 0.1 μs

P0N-3

1 PW = 10 μs

P0N-4

PW = 3.33 μs

P0N-5

PW = 1 μs

P0N-6

3 PW = 30 μs

P0N-7

PW = 10 μs

P0N-8

PW = 3 μs

P0N-9

10 PW = 100 μs

P0N-10

PW = 33.3 μs

P0N-11

PW = 10 μs

P0N-12

Table 2. Q3N (swept-frequency) pulsed radar waveform parameters, 1 MHz/μs chirp.

Duty Cycle

(percent)

Chirped Pulse Group 1 Chirped Pulse Group 2 Chirped Pulse Group 3

PW (μs) PRR (s-1

) PW (μs) PRR (s-1) PW (μs) PRR (s-1)

1 10 1000

Q3N-1 1 10,000Q3N-2 0.33 30,000Q3N-3

10 100 → 10 1,000 → 10,000

Q3N-4 10 10,000

Q3N-5* 3.3 30,303Q3N-6

20 200 → 10 1,000 → 20,000

Q3N-7 20 → 10 20,000

Q3N-8* 6.6 30,303Q3N-9

30 300 → 10 1,000 → 30,000

Q3N-10 30 → 10 10,000 → 30,000Q3N-11* 10 30,000

Q3N-12*

* These waveforms were not used for testing with this LTE network because they were redundant to other waveforms created 

when the pulse width was adjusted to maintain a maximum 10 MHz wide chirp.

8
Table 3. Additional special interference waveforms used in testing.

Duty Cycle (percent) Waveform Names PW (μs) PRR (pulses/sec)

0.4 ECC-1

WFM-1 4 1,000

3 ECC-2

WFM-2 100 300

0.05 TDWR

P0N-13 1 2,000

An overall goal of the interference waveform design was to vary interference duty cycle (DC)

values in an approximately logarithmic progression: 1 percent, 3 percent 10 percent, and so forth.

PW and PRR values were adjusted to achieve these DCs. For the P0N pulses, setting DC was 

straightforward: DC = PW ∙ PRR. The P0N pulses were centered at 3600 MHz for the downlink 

testing and 3520 MHz for the uplink testing. Two additional P0N-1 tests were performed on the 

downlink path at +2 MHz and +4 MHz offsets from 3600 MHz (3602 MHz and 3604 MHz, 

respectively).

For the Q3N (chirped) pulses, achieving the proper duty cycle can be more complicated. While 

the goal for a DC progression was the same for the chirped pulses as for the P0N pulses, the 

chirp bandwidth was an additional degree of freedom in the waveform design. The authors dealt 

with this by holding the chirp frequency-sweeping rate constant at 1 MHz per microsecond.10 In 

order to maintain a 1 MHz/microsecond chirp rate within the 10 MHz LTE receiver bandwidth 

while also maintaining DC, pulse widths could not be allowed to exceed 10 μs. This adjustment 

to PW required adjustment of PRR to maintain duty cycle. The relationship is one of 

proportionality:

DC = τ′ ∙ PRR ′ = τ0 ∙ PRR0

where τ0 = full pulse width of a chirped radar pulse, PRR0 = full pulse repetition rate for chirped 

radar pulses, τ

’ = reduced pulse width for testing, and PRR’ = increased pulse repetition rate for 

testing. Since the reduced pulse widths chirped 10 MHz in 10 μs and were 10 μs long, the 

adjusted PRR values were computed as:

PRR′ = τ0 ∙ PRR0

τ′ = τ0 ∙ PRR010 μs

These adjustments are shown in Table 2. The chirp direction monotonically increased in

frequency and the center frequencies of the Q3N signals were 3600 MHz and 3520 MHz for the 

downlink and uplink tests, respectively. Making these Q3N adjustments for PWs greater than 10 

microseconds created redundant test waveforms with identical parameters. The authors decided 

to only use one of each of the redundant waveforms. The following waveforms were not used 

during this test effort: Q3N-5 (same as Q3N-4), Q3N-8 (same as Q3N-7), Q3N-11 (same as 

Q3N-10), and Q3N-12 (same as Q3N-10).

10 A chirp rate of 1 MHz per microsecond represents a nominal chirp rate for modern radars.

9

 
2.3 Testing Methodology

The overall concept of the testing methodology was to measure and record the LTE diagnostics 

of data throughput, BLER, and MCS usage for both the downlink and uplink, and additionally 

UE transmit power and RB usage for the uplink. These diagnostics were recorded for a wide 

range of interference power levels, I, for every interference waveform listed in Tables 1–3 except 

for the redundant waveforms.

The ratio of Savg/I was measured with monitoring spectrum analyzer(s) (Figure 3) in an 8 MHz 

resolution bandwidth, and recorded. Peak detection was used to measure radar interference 

power and average detection was used for the Gaussian noise interference measurements; Savg

was always measured using average detection, consistent with the LTE diagnostic software. The

value of Savg/I (in dB) was used to determine I in the receiver by subtracting it from the known 

value of Savg = -75 dBm for the downlink and Savg = -85 dBm for the uplink initial condition 

(with no interference). 

Interference power, I, for the downlink case needed to be calculated as total power in the UE 

receiver downlink bandwidth of 9 MHz. For the uplink, I was calculated in the 7.2 MHz 

bandwidth of the eNB receiver (with no interference). It was assumed, for the purposes of this 

study, that the respective LTE receiver bandwidths were the same as the nominal emission 

bandwidths for the both the uplink and downlink. It is noted that for the uplink case, the UE was 

able to change the number of resource blocks in use, thereby changing the total bandwidth. The 

7.2 MHz eNB receiver bandwidth represents the nominal 40 RBs in use by the UE when there 

was no interference. 11

For each interference waveform, the testing proceeded by first establishing a communication link

between the eNB and the UE in a non-interference state (that is, with the VSG RF output turned 

off). Interference from the VSG was then injected continuously at a power level that did not 

appear to affect throughput, shown on a real-time diagnostic display, while the diagnostic 

software recorded dedicated electronic (comma-separated variable, or CSV format) files 

containing several key diagnostics including: data throughput, BLER, MCS, UE transmit power, 

eNB received signal strength indicator (RSSI), and dedicated RBs for both the uplink and 

downlink. Diagnostics were recorded for approximately 60 seconds,

12 after which the recording 

was stopped. The interference power was then increased (usually in 5 or 10 dB increments) and 

the LTE diagnostic software was restarted. This process was repeated until throughput decreased 

to zero or until the VSG reached the maximum available output power level (while not 

exceeding an upper limit for reverse power into the LTE system). It should be noted that the 

closed loop rate control algorithm of the eNB scheduler was set to achieve a target BLER on first 

transmission to 10% for the downlink and 30% for the uplink.

In addition to the continuous interference tests described above, burst tests were also performed 

using selected radar interference waveforms. For these tests, a communication link was 

11 The average internal inherent noise level of the UE receiver was calculated based on a 7 dB noise figure 

(provided by the industry participant) to be -97.5 dBm in a 9 MHz bandwidth for the downlink and -98.4 

dBm in a 7.2 MHz bandwidth for the uplink.

12 120–180 seconds for subsequent radar interference burst testing.

10

 
established and the diagnostic software was started. Radar interference was then injected by 

bursting 20 radar pulses,

13 with the PWs and PRRs described in Tables 1–3, every 5 seconds. 

This simulated a radar azimuthal scan with a 72 degree/sec rotation rate. For all burst tests 

performed on the downlink, the interference power level, I, was set such that it was equal to or 

greater than the value of I that caused significant throughput degradation during the respective 

continuous test. For the uplink case, the interference power level, I, was set to -25 dBm. For the 

downlink, I was between -50 dBm and -30 dBm. Diagnostics were recorded for approximately 

120–180 seconds with the interference on. For the downlink case radar waveforms P0N-5, 

P0N-8, P0N-11, Q3N-1, Q3N-4, Q3N-7, and Q3N-10 were burst-tested. For the uplink case 

radar waveforms P0N-1, P0N-2, P0N-5, P0N-8, P0N-10, P0N-11, Q3N-1, Q3N-4, Q3N-6, 

Q3N-7, Q3N-9, and Q3N-10 were burst-tested. More cases were tested for the uplink because

the authors believe this is the real-world scenario in which interference would be the most 

prominent.

13 For volume air-search radars in general, a nominal 15 to 20 pulse echo returns must be integrated to 

declare a target.

11

 
3 INTERFERENCE-EFFECTS TEST RESULTS

3.1 Downlink Interference-Effects Results

3.1.1 Continuous Interference Testing

Figures 4–29 show the effects of radar waveform interference and Gaussian noise interference on 

LTE UE receiver (downlink) data throughput (blue, upper line) and BLER (green, lower line).

For each data point on each graph, the circle indicates the mean throughput or BLER as 

calculated from all of the data samples recorded by the diagnostic software for each interference 

waveform power level. The number of samples used to calculate mean and standard deviation 

was approximately 100 for throughput and over 2,000 for BLER. The error bars associated with 

each point show the standard deviation from the mean. In the figures, a smoothing spline was 

used to demonstrate general trends for both throughput and BLER.

Each plot is followed by a table (Tables 5–30) indicating how the MCS was affected by the 

interference waveforms as the interference power level was varied. Downlink multi-antenna 

transmissions are reported with a “Rank 1” or “Rank 2” label in each table and are mutually 

exclusive. These rank values indicate the number of useful transmission layers as determined 

from UE reporting and, ultimately, indicate the transmission mode used by the test bed network 

at any given time [6]. In addition to showing which MCSs were used in each rank, the tables also 

indicate what percentage of the time each rank was used during the data recording for the given 

interference power level, I. 

The interference power levels, I, shown in the MCS tables coincide with the points in the graph 

showing the effects of the same interference waveform on throughput and BLER. Table 4

provides a key indicating what each of the numbers in the MCS tables means in terms of MCS, 

channel quality indicator (CQI) and spectral efficiency [7].

The LTE network was configured to have a signal to noise ratio (S/N) of +22.5 dB for the 

baseline downlink condition (with no interference) and was set by the industry participant as 

standard practice.

12
Table 4. Relationship between MCS, CQI, modulation, and spectral efficiency.

MCS CQI Modulation Spectral Efficiency MCS CQI Modulation Spectral Efficiency

0

2

QPSK

0.2344 16

9 16 QAM 2.5684

1 0.3057 17

64 QAM

2.5684

2

3

0.3770 18

10

2.7305

3 0.4893 19 3.0264

4

4

0.6016 20

11

3.3223

5 0.7393 21 3.6123

6

5

0.8770 22

12

3.9023

7 1.0264 23 4.2128

8

6

1.1758 24

13

4.5234

9 1.3262 25 4.8193

10

16 QAM

1.3262 26

14

5.1152

11

7

1.4766 27 5.3349

12 1.6953 28 15 5.5547

13

8

1.9141 29 QPSK

14 2.1602 30 16 QAM Reserved

15 9 2.4063 31 64 QAM

13
Figure 4. Data throughput and BLER for 10 MHz wide Gaussian noise interference.

Table 5. MCS state for 10 MHz wide Gaussian noise interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-93 2 23 23 1.90 7 23 23 1 23 23 98.10

-90 6 22 22 1.80 9 22 23 9 22 23 98.20

-87 10 19 22 0.75 4 19 21 2 19 21 99.25

-84 15 16 16 3.70 13 15 23 13 15 23 96.30

-81 3 13 18 2.72 4 11 23 8 11 15 97.28

-78 0 9 10 1.49 6 8 13 4 8 23 98.51

-75 4 6 22 2.42 3 5 22 3 5 23 97.58

-72 1 2 3 2.11 0 2 23 0 2 14 97.89

-69 0 0 15 98.23 0 0 23 0 0 23 1.77

14
Figure 5. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) 

interference.

Table 6. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0 2 23 23 14 23 23 100

-70 N/A N/A N/A 0 16 23 23 7 23 23 100

-65 N/A N/A N/A 0 1 22 23 6 22 23 100

-60 N/A N/A N/A 0 6 21 23 15 21 23 100

-55 N/A N/A N/A 0 6 20 23 5 20 23 100

-50 N/A N/A N/A 0 10 19 23 1 19 23 100

-45 N/A N/A N/A 0 11 15 23 11 15 23 100

-40 N/A N/A N/A 0 5 14 23 7 14 23 100

-35 N/A N/A N/A 0 3 21 23 0 21 23 100

-30 N/A N/A N/A 0 2 14 23 3 14 23 100

-25 N/A N/A N/A 0 7 12 17 3 12 16 100

15
Figure 6. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) 

interference off-tuned from the LTE eNB center transmit frequency by 2 MHz.

Table 7. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) interference off-tuned 

from the LTE eNB center transmit frequency by 2 MHz.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 6 6 10 0.01 4 23 23 1 23 23 99.99

-70 12 12 12 0.00 17 23 23 7 23 23 100.00

-65 23 23 23 0.80 1 23 23 4 23 23 99.20

-60 21 22 23 0.80 15 22 23 12 22 23 99.20

-55 4 20 23 1.06 3 20 23 7 20 23 98.94

-50 20 21 21 0.73 17 20 23 2 20 23 99.27

-45 16 19 21 3.27 3 19 23 8 19 23 96.73

-40 5 20 23 1.05 3 19 23 1 19 23 98.95

-35 9 14 23 2.44 8 13 23 8 13 23 97.56

-30 3 14 23 0.12 1 13 23 9 13 23 99.88

-25 5 23 23 2.81 7 22 23 9 22 23 97.19

16
Figure 7. Data throughput and BLER for P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) 

interference off-tuned from the LTE eNB center transmit frequency by 4 MHz.

Table 8. MCS state for P0N-1 (PW = 1 μs, PRR = 1000/sec, DC = 0.1%) interference off-tuned 

from the LTE eNB center transmit frequency by 4 MHz.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0.00 0 23 23 7 23 23 100.00

-70 10 23 23 0.08 12 23 23 4 23 23 99.92

-65 21 23 23 0.37 1 23 23 4 23 23 99.63

-60 3 23 23 2.46 13 23 23 6 23 23 97.54

-55 9 21 23 1.21 3 22 23 8 22 23 98.79

-50 19 20 23 1.79 10 20 23 0 20 23 98.21

-45 18 20 21 0.29 14 19 22 13 19 22 99.71

-40 6 20 21 0.14 4 19 21 15 19 23 99.86

-35 7 16 23 2.71 4 18 23 0 18 23 97.29

-30 15 19 20 1.28 1 19 21 7 19 22 98.72

-25 13 14 22 0.57 9 13 19 9 13 18 99.43

17
Figure 8. Data throughput and BLER for P0N-2 (PW = 0.33 μs, PRR = 3,000/sec, DC = 0.1%) 

interference.

Table 9. MCS state for P0N-2 (PW = 0.33 μs, PRR = 3000/sec, DC = 0.1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0 14 23 23 13 23 23 100

-70 N/A N/A N/A 0 1 23 23 13 23 23 100

-65 N/A N/A N/A 0 0 23 23 0 23 23 100

-60 N/A N/A N/A 0 4 23 23 0 23 23 100

-55 N/A N/A N/A 0 11 21 23 8 21 23 100

-50 N/A N/A N/A 0 7 18 23 7 18 23 100

-45 N/A N/A N/A 0 0 18 23 3 18 23 100

-40 N/A N/A N/A 0 0 14 23 0 14 23 100

-35 N/A N/A N/A 0 0 13 23 0 13 23 100

-30 N/A N/A N/A 0 0 6 22 0 6 22 100

-25 N/A N/A N/A 0 0 6 23 0 6 23 100

18
Figure 9. Data throughput and BLER for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) 

interference.

Table 10. MCS state for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0.00 9 23 23 2 23 23 100.00

-70 N/A N/A N/A 0.00 10 23 23 12 23 23 100.00

-65 N/A N/A N/A 0.00 23 23 23 23 23 23 100.00

-60 N/A N/A N/A 0.00 2 21 23 1 21 23 100.00

-55 N/A N/A N/A 0.00 14 19 23 4 19 23 100.00

-50 N/A N/A N/A 0.00 5 23 23 4 23 23 100.00

-45 N/A N/A N/A 0.00 0 6 23 3 6 23 100.00

-40 1 22 23 99.76 0 0 11 0 0 20 0.24

-35 11 18 21 99.99 4 4 15 0 18 18 0.01

-30 N/A N/A N/A 0.00 10 10 19 8 8 13 100.00

-25 1 13 23 99.50 23 23 23 23 23 23 0.50

19
Figure 10. Data throughput and BLER for P0N-4 (PW = 10 μs, PRR = 1,000/sec, DC = 1.0%)

interference.

Table 11. MCS state for P0N-4 (PW = 10 μs, PRR = 1000/sec, DC = 1.0%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0.00 17 23 23 6 23 23 100.00

-70 5 5 18 0.01 23 23 23 5 23 23 99.99

-65 0 0 23 0.27 6 22 23 19 22 23 99.73

-60 0 0 23 1.96 2 22 23 12 22 23 98.04

-55 0 20 20 3.27 8 19 23 2 19 23 96.73

-50 0 0 23 3.13 1 19 23 0 19 23 96.87

-45 0 14 23 2.98 0 13 23 5 13 23 97.02

-40 0 0 23 2.68 11 14 23 6 14 23 97.32

-35 0 0 22 0.79 4 12 23 4 12 23 99.21

-30 0 0 21 0.88 5 13 22 3 13 22 99.12

-25 0 8 22 2.82 4 7 20 4 7 21 97.18

20
Figure 11. Data throughput and BLER for P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) 

interference.

Table 12. MCS state for P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 13 13 13 0.00 1 23 23 4 23 23 100.00

-70 3 11 23 0.01 5 23 23 23 23 23 99.99

-65 0 0 23 0.07 23 23 23 7 23 23 99.93

-60 0 21 23 2.13 8 21 23 1 21 23 97.87

-55 0 21 22 3.68 13 20 23 3 20 23 96.32

-50 0 0 23 1.32 7 15 23 1 15 23 98.68

-45 0 0 23 4.22 3 13 23 0 13 23 95.78

-40 0 11 17 4.49 2 7 23 2 7 23 95.51

-35 0 8 23 39.67 0 5 23 0 5 23 60.33

-30 0 2 23 94.69 0 23 23 0 23 23 5.31

21
Figure 12. Data throughput and BLER for P0N-6 (PW = 1.0 μs, PRR = 10,000/sec, DC = 1%) 

interference.

Table 13. MCS state for P0N-6 (PW = 1.0 μs, PRR = 10,000/sec, DC = 1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 0 23 0.01 5 23 23 2 23 23 99.99

-70 0 22 23 0.19 19 21 23 5 21 23 99.81

-65 0 0 23 0.40 9 23 23 2 23 23 99.60

-60 0 0 23 2.91 11 14 23 4 14 23 97.09

-55 0 0 19 1.20 2 18 23 14 18 23 98.80

-50 20 23 23 99.99 13 14 23 2 20 20 0.01

-45 17 22 23 99.26 0 23 23 10 23 23 0.74

-40 0 17 23 99.21 3 23 23 9 23 23 0.79

-35 1 8 23 99.25 2 23 23 3 23 23 0.75

-30 0 4 23 46.31 9 23 23 9 23 23 53.69

22
Figure 13. Data throughput and BLER for P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) 

interference.

Table 14. MCS state for P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 0 23 0.01 13 23 23 5 23 23 99.99

-70 N/A N/A N/A 0.00 5 23 23 10 23 23 100.00

-65 0 23 23 0.01 9 23 23 2 23 23 99.99

-60 0 22 23 0.72 4 22 23 2 22 23 99.28

-55 0 0 20 0.41 3 18 23 4 18 23 99.59

-50 0 0 22 1.93 5 15 22 12 15 22 98.07

-45 0 18 23 32.83 2 12 23 5 12 23 67.17

-40 0 18 23 96.38 2 11 23 2 11 23 3.62

-35 0 15 23 98.86 4 23 23 4 23 23 1.14

-30 1 15 23 98.88 4 23 23 4 23 23 1.12

-25 0 6 23 97.18 3 23 23 2 23 23 2.82

23
Figure 14. Data throughput and BLER for P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) 

interference.

Table 15. MCS state for P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS Min

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 0 23 0.03 23 23 23 21 23 23 99.97

-70 9 9 9 0.00 4 23 23 2 23 23 100.00

-65 0 0 23 1.55 5 23 23 8 23 23 98.45

-60 0 0 23 0.62 2 22 23 11 22 23 99.38

-55 0 0 23 1.96 2 20 23 5 20 23 98.04

-50 0 0 23 3.72 3 15 23 3 15 23 96.28

-45 0 0 23 6.37 0 12 23 0 12 23 93.63

-40 0 8 23 9.63 0 6 23 0 6 23 90.37

-35 0 0 23 62.39 0 23 23 0 23 23 37.61

24
Figure 15. Data throughput and BLER for P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) 

interference.

Table 16. MCS state for P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0.00 3 23 23 7 23 23 100.00

-70 0 23 23 0.02 11 23 23 0 23 23 99.98

-65 0 23 23 1.89 4 23 23 10 23 23 98.11

-60 0 0 22 1.00 3 21 23 7 21 23 99.00

-55 0 0 23 1.53 10 18 23 12 18 23 98.47

-50 0 0 19 1.14 8 12 19 5 12 19 98.86

-45 0 8 23 30.24 0 23 23 0 23 23 69.76

25
Figure 16. Data throughput and BLER for P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) 

interference.

Table 17. MCS state for P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 18 18 18 0.00 16 23 23 2 23 23 100.00

-70 N/A N/A N/A 0.00 1 23 23 5 23 23 100.00

-65 0 23 23 5.35 9 22 23 10 22 23 94.65

-60 0 21 21 2.29 2 20 23 5 20 23 97.71

-55 0 0 19 2.29 10 18 23 1 18 23 97.71

-50 0 15 20 1.26 11 12 23 1 12 20 98.74

-45 0 8 15 2.04 5 8 17 3 8 17 97.96

-40 0 0 23 3.21 0 5 23 2 5 23 96.79

26
Figure 17. Data throughput and BLER for P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) 

interference.

Table 18. MCS state for P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 N/A N/A N/A 0.00 1 23 23 1 23 23 100.00

-72 0 23 23 1.65 9 23 23 2 23 23 98.35

-69 0 0 23 0.02 1 23 23 4 23 23 99.98

-66 0 0 23 1.60 20 23 23 19 23 23 98.40

-63 0 0 23 2.06 4 22 23 17 22 23 97.94

-60 0 0 22 3.25 12 20 23 7 20 23 96.75

-57 0 0 23 1.16 0 18 23 9 18 23 98.84

-54 0 0 23 1.67 11 17 23 0 17 23 98.33

27
Figure 18. Data throughput and BLER for P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) 

interference.

Table 19. MCS state for P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 9 9 9 0.01 1 23 23 2 23 23 99.99

-72 2 23 23 0.02 2 23 23 10 23 23 99.98

-69 4 4 21 0.01 0 23 23 13 23 23 99.99

-66 0 23 23 1.74 23 23 23 7 23 23 98.26

-63 0 0 23 0.09 20 22 23 18 22 23 99.91

-60 0 0 23 2.86 0 20 23 14 20 23 97.14

-57 0 0 23 1.37 7 18 23 13 18 23 98.63

-54 0 0 21 2.54 0 14 23 0 14 23 97.46

28
Figure 19. Data throughput and BLER for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) 

interference.14

Table 20. MCS State for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-80 0 0 23 0.74 8 23 23 5 23 23 99.26

-75 0 0 21 5.15 18 20 23 18 20 23 94.85

-70 0 0 23 0.47 15 19 23 0 19 23 99.53

-65 0 0 23 2.35 0 19 23 1 19 23 97.65

-60 0 0 22 1.58 1 13 23 0 13 23 98.42

-55 0 0 22 0.21 2 8 23 4 8 23 99.79

-50 0 0 21 0.12 4 8 23 1 8 23 99.88

-45 0 0 21 0.15 4 8 23 4 8 23 99.85

-40 0 0 21 0.15 0 6 23 4 6 23 99.85

-35 0 19 19 0.15 0 6 23 4 6 23 99.85

14 The BLER points that are off the graph are believed to be the result of erroneous diagnostic software behavior.

29

 
Figure 20. Data throughput and BLER for Q3N-2 (PW = 1 μs, PRR = 10,000/sec, DC = 1.0%) 

interference.

Table 21. MCS state for Q3N-2 (PW = 1 μs, PRR = 10,000/sec, DC = 1.0%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 0 15 0.01 3 23 23 12 23 23 99.99

-70 0 0 5 0.01 8 23 23 3 23 23 99.99

-65 0 0 23 0.03 15 23 23 23 23 23 99.97

-60 0 21 22 0.58 0 21 23 0 21 23 99.42

-55 0 0 21 2.82 4 18 23 4 18 23 97.18

-50 0 0 21 0.81 11 14 21 11 14 21 99.19

-45 0 18 19 9.40 0 12 23 1 12 23 90.60

-40 0 14 23 99.30 1 23 23 10 23 23 0.70

30
Figure 21. Data throughput and BLER for Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) 

interference.

Table 22. MCS state for Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 2 23 23 0.02 12 23 23 4 23 23 99.98

-70 0 0 23 0.77 20 23 23 23 23 23 99.23

-65 0 0 23 0.42 7 22 23 1 22 23 99.58

-60 0 20 23 3.28 9 20 23 6 20 23 96.72

-55 0 15 23 6.87 3 14 23 7 14 23 93.13

-50 0 13 13 0.50 1 12 17 8 12 19 99.50

-45 0 0 8 2.78 2 5 14 2 5 9 97.22

31
Figure 22. Data throughput and BLER for Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to 

PW = 100 μs, PRR = 1,000/sec), DC = 10%) interference.

Table 23. MCS state for Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to PW = 100 μs, 

PRR = 1,000/sec), DC = 10%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 0 0 23 0.02 15 23 23 6 23 23 99.98

-80 0 0 23 3.71 5 23 23 10 23 23 96.29

-75 0 21 22 1.10 4 21 22 15 21 22 98.90

-70 0 0 23 2.51 13 16 22 10 16 19 97.49

-65 1 23 23 100.0 N/A N/A N/A N/A N/A N/A 0.00

-60 6 23 23 100.0 15 15 15 8 8 8 0.00

-60 12 23 23 100.0 1 1 1 7 7 12 0.00

32
Figure 23. Data throughput and BLER for Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) 

interference.

Table 24. MCS state for Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 N/A N/A N/A 0.00 4 23 23 10 23 23 100.00

-80 0 23 23 0.83 9 23 23 23 23 23 99.17

-75 0 22 22 2.82 1 21 23 4 21 23 97.18

-70 0 19 20 4.27 2 19 23 17 19 23 95.73

-65 0 15 23 2.57 0 15 23 1 15 23 97.43

-60 18 23 23 99.99 11 23 23 10 23 23 0.01

-55 15 20 23 99.99 11 11 21 1 1 20 0.01

33
Figure 24. Data throughput and BLER for Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to 

PW = 200 μs, PRR = 1,000/sec), DC = 20%) interference.

Table 25. MCS state for Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to PW = 200 μs, 

PRR = 1,000/sec), DC = 20%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

%

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-80 0 22 23 1.54 18 22 23 11 22 23 98.46

-75 0 0 19 2.10 14 19 22 14 19 22 97.90

-70 6 23 23 100.0 15 17 17 13 13 17 0.00

-65 12 23 23 100.0 0 0 0 6 6 6 0.00

-60 13 21 23 99.99 12 12 22 10 18 23 0.01

-55 10 16 23 99.54 6 23 23 3 23 23 0.46

34
Figure 25. Data throughput and BLER for Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) 

interference.

Table 26. MCS state for Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 0 0 23 0.01 1 23 23 3 23 23 99.99

-80 0 22 23 8.13 1 22 23 3 22 23 91.87

-75 0 20 20 6.92 5 19 23 3 19 23 93.08

-70 0 23 23 46.65 11 14 23 11 14 23 53.35

-65 4 23 23 100.0 18 18 18 7 7 19 0.00

-60 14 21 23 99.99 14 14 14 7 7 13 0.01

-55 1 15 23 88.22 2 23 23 10 23 23 11.78

35
Figure 26. Data throughput and BLER for Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent 

to PW = 300 μs, PRR = 1,000/sec), DC = 30%) interference.

Table 27. MCS state for Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent to PW = 300 μs, 

PRR = 1,000/sec), DC = 30%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-90 11 11 23 0.00 2 23 23 23 23 23 100.00

-85 3 23 23 8.23 2 23 23 18 23 23 91.77

-80 0 0 21 8.33 1 20 21 5 20 21 91.67

-75 0 0 16 8.33 2 15 19 3 15 21 91.67

-70 0 23 23 99.13 0 13 18 8 13 18 0.87

-65 12 23 23 100.0 6 6 12 1 1 20 0.00

-60 7 21 23 100.0 11 11 23 5 5 13 0.00

36
Figure 27. Data throughput and BLER for ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 

0.4%) interference.

Table 28. MCS state for ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 0.4%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 0 23 0.01 20 23 23 1 23 23 99.99

-70 14 14 14 0.00 13 23 23 4 23 23 100.00

-65 3 3 23 0.01 1 23 23 13 23 23 99.99

-60 0 0 23 1.44 6 23 23 5 23 23 98.56

-55 0 22 23 2.19 4 21 23 2 21 23 97.81

-50 0 0 20 1.10 2 19 23 5 19 23 98.90

-45 0 0 23 1.78 12 17 23 12 17 23 98.22

-40 0 0 23 1.25 11 12 23 11 12 23 98.75

-35 0 0 20 0.48 0 11 23 0 11 23 99.52

-30 0 0 23 2.89 0 8 23 0 8 23 97.11

-25 0 14 23 67.65 0 7 23 0 7 23 32.35

37
Figure 28. Data throughput and BLER for ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 

3%) interference.

Table 29. MCS state for ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 3%) interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 23 23 23 0.01 2 23 23 5 23 23 99.99

-70 0 23 23 0.39 13 23 23 20 23 23 99.61

-65 0 0 23 1.41 4 23 23 19 23 23 98.59

-60 0 0 23 1.33 0 20 23 7 20 23 98.67

-55 0 0 20 1.82 1 19 23 2 19 23 98.18

-50 0 0 21 1.17 4 12 23 4 12 23 98.83

-45 0 0 23 1.13 0 7 23 0 7 23 98.87

-40 0 0 23 0.95 0 6 23 0 6 23 99.05

-35 0 0 21 0.62 4 8 19 4 8 19 99.38

-30 0 2 20 1.66 0 6 23 0 6 23 98.34

-25 0 0 23 4.55 0 6 23 0 6 23 95.45

38
Figure 29. Data throughput and BLER for P0N-13/TDWR (PW = 1 μs, PRR = 2,000/sec, DC = 

0.05%) interference.

Table 30. MCS state for P0N-13/TDWR (PW = 1 μs, PRR = 2,000/sec, DC = 0.05%) 

interference.

I

dBm

Rank 1

Rank 2

Channel 0 Channel 1 % 

Time 

Min Used

MCS

Most 

Frequent 

MCS

Max 

MCS

% 

Time 

Used

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-75 0 23 23 0.02 14 23 23 2 23 23 99.98

-70 0 23 23 0.06 1 23 23 6 23 23 99.94

-65 0 0 23 5.17 0 22 23 2 22 23 94.83

-60 0 0 22 2.97 8 21 23 11 21 23 97.03

-55 0 20 20 4.83 5 19 23 8 19 23 95.17

-50 0 0 23 1.89 9 19 23 5 19 23 98.11

-45 0 0 22 3.08 2 14 23 5 14 23 96.92

-40 0 14 20 0.94 3 13 23 2 13 23 99.06

-35 0 0 20 0.76 4 12 23 4 12 23 99.24

-30 0 0 23 4.11 4 7 23 0 7 23 95.89

-25 0 7 22 1.95 3 6 23 2 6 23 98.05

39
3.1.2 Burst Interference Testing

As noted previously, radar beams normally scan intermittently across fixed points in space. Burst 

interference testing replicated realistic radar-beam interference scenarios by injecting 20 pulses 

of radar interference every 5 seconds throughout the collection of diagnostic data. Figures 30–36

provide the results of the burst tests for the downlink. These graphs show how data throughput 

(top graph) and MCS (bottom graph) varied over time during the total duration of the data 

recording. MCS Rank 1 is presented as discrete points in these graphs because the LTE network 

infrequently used the rank 1 transmission strategy during these tests. Data points were collected 

every 0.627–100 ms. Keyed from timestamps contained in the diagnostic software data, the two 

graphs in each figure are time synchronized. Data recordings were manually initiated and, 

consequently, the data collection for each parameter began at offset times. For example, in 

Figure 30, one can see that the MCS recording both began before and stopped after the data 

throughput recording. The first timestamp in either the throughput data or the MCS data 

(whichever was started first) was used to determine the starting time of each graph.

For all burst tests performed on the downlink, the interference power level, I, was set such that it

was equal to or greater than the value of I that caused significant throughput degradation during 

the respective continuous test. 

Figure 30. Data throughput and MCS state for P0N-5 interference (Ipeak = -35 dBm).

40
Figure 31. Data throughput and MCS state for P0N-8 interference (Ipeak = -35 dBm).

Figure 32. Data throughput and MCS state for P0N-11 interference (Ipeak = -35 dBm).

41
Figure 33. Data throughput and MCS state for Q3N-1 interference (Ipeak = -30 dBm).

Figure 34. Data throughput and MCS state for Q3N-4 interference (Ipeak = -45 dBm).

42
Figure 35. Data throughput and MCS state for Q3N-7 interference (Ipeak = -50 dBm).

Figure 36. Data throughput and MCS state for Q3N-10 interference (Ipeak = -50 dBm).

43
3.2 Uplink Interference-Effects Results

3.2.1 Continuous Interference Testing

Figures 37–60 show the effects of radar waveform interference and Gaussian noise interference 

on LTE eNB receiver (uplink) data throughput, BLER, RB usage, and UE transmit power level. 

Each figure is divided into three graphs. The top graph displays mean data throughput as blue 

points with error bars showing the standard deviation from the mean. The green line on the top 

graph depicts the mean UE transmit power level. The middle graph shows the mean BLER, 

again with standard-deviation error bars. The bottom graph shows how the mean number of RBs

varied as I increased. In the figures, a smoothing spline was applied to demonstrate general 

trends for both data throughput and BLER as a function of interference power, I.

As with the downlink case, the number of samples used to calculate mean and standard deviation 

was approximately 100 for throughput and over 2,000 for BLER. The mean RB usage and mean 

UE transmit power were calculated from tens of thousands of samples provided by the diagnostic 

software.

Each plot is followed by a table (Tables 31–53) indicating how the MCS was affected by the 

interference waveforms as the interference level was increased. For the uplink, only a single 

transmission channel was used. The interference power levels, I, shown in the MCS tables 

coincide with the points in each graph showing the effects of the same interference waveform on 

throughput, UE transmit power, BLER, and RBs. Table 4 in Section 3.1.1 provides a key 

indicating what each of the numbers in the MCS tables means in terms of MCS.

The LTE network was configured to have a signal to noise ratio (S/N) of approximately +13 dB 

for the baseline uplink condition (with no interference) and was set by the industry participant as 

standard practice.

44
Figure 37. Data throughput, UE transmit (Tx) power, BLER, and RB usage for 10 MHz wide 

Gaussian noise interference.

Table 31. MCS state for 10 MHz wide Gaussian noise interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-105 20 20 20

-100 20 20 20

-95 7 20 20

-90 7 20 20

-85 7 20 20

-80 18 19 20

-75 18 18 20

-70 9 20 20

45
Figure 38. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-1 (PW = 1

μs, PRR = 1,000/sec, DC = 0.1%) interference.

Table 32. MCS state for P0N-1 (PW = 1 μs, PRR = 1,000/sec, DC = 0.1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 20 20 20

46
Figure 39. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-2 (PW = 

0.33 μs, PRR = 3,000/sec, DC = 0.1%) interference.

Table 33. MCS state for P0N-2 (PW = 0.33 μs, PRR = 3,000/sec, DC = 0.1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 20 20 20

47
Figure 40. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-3 (PW = 0.1 

μs, PRR = 10,000/sec, DC = 0.1%) interference.

Table 34. MCS state for P0N-3 (PW = 0.1 μs, PRR = 10,000/sec, DC = 0.1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-60 20 20 20

-55 20 20 20

-50 20 20 20

-45 20 20 20

-40 20 20 20

-35 20 20 20

-30 18 20 20

-25 19 20 20

48
Figure 41. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-4 (PW = 10 

μs, PRR = 1,000/sec, DC = 1%) interference.

Table 35. MCS state for P0N-4 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 20 20 20

49
Figure 42. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-5 (PW = 

3.33 μs, PRR = 3,000/sec, DC = 1%) interference.

Table 36. MCS state for P0N-5 (PW = 3.33 μs, PRR = 3,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 18 20 20

-35 18 18 20

-25 20 20 20

50
Figure 43. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-6 (PW = 1 

μs, PRR = 10,000/sec, DC = 1%) interference.

Table 37. MCS state for P0N-6 (PW = 1 μs, PRR = 10,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 18 20 20

-35 18 20 20

-25 17 20 20

51
Figure 44. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-7 (PW = 30 

μs, PRR = 1,000/sec, DC = 3%) interference.

Table 38. MCS state for P0N-7 (PW = 30 μs, PRR = 1,000/sec, DC = 3%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 20 20 20

52
Figure 45. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-8 (PW = 10 

μs, PRR = 3,000/sec, DC = 3%) interference.

Table 39. MCS state for P0N-8 (PW = 10 μs, PRR = 3,000/sec, DC = 3%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 7 20 20

-65 20 20 20

-55 15 20 20

-45 20 20 20

-35 10 20 20

53
Figure 46. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-9 (PW = 3 

μs, PRR = 10,000/sec, DC = 3%) interference.

Table 40. MCS state for P0N-9 (PW = 3 μs, PRR = 10,000/sec, DC = 3%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-85 20 20 20

-70 20 20 20

-55 20 20 20

-40 20 20 20

-25 13 20 20

54
Figure 47. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-10 (PW = 

100 μs, PRR = 1,000/sec, DC = 10%) interference.

Table 41. MCS state for P0N-10 (PW = 100 μs, PRR = 1,000/sec, DC = 10%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-90 20 20 20

-80 7 20 20

-70 20 20 20

-60 20 20 20

-50 18 20 20

-40 13 20 20

55
Figure 48. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-11 (PW = 

33.3 μs, PRR = 3,000/sec, DC = 10%) interference.

Table 42. MCS state for P0N-11 (PW = 33.3 μs, PRR = 3,000/sec, DC = 10%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-85 20 20 20

-70 20 20 20

-55 18 20 20

-40 15 20 20

56
Figure 49. Data throughput, UE transmit (Tx) power, BLER, and RB usage for P0N-12 (PW = 10 

μs, PRR = 10,000/sec, DC = 10%) interference.

Table 43. MCS state for P0N-12 (PW = 10 μs, PRR = 10,000/sec, DC = 10%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-75 20 20 20

-70 20 20 20

-65 19 20 20

-60 18 20 20

-55 18 20 20

-50 17 20 20

-45 17 20 20

-40 15 20 20

57
Figure 50. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-1 (PW = 10 

μs, PRR = 1,000/sec, DC = 1%) interference.

Table 44. MCS state for Q3N-1 (PW = 10 μs, PRR = 1,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 19 20 20

-25 20 20 20

58
Figure 51. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-2 (PW = 

0.33 μs, PRR = 10,000/sec, DC = 1%) interference.

Table 45. MCS state for Q3N-2 (PW = 0.33 μs, PRR = 10,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 18 20 20

-35 19 20 20

-25 18 19 20

59
Figure 52. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-3 (PW = 

0.33 μs, PRR = 30,000/sec, DC = 1%) interference.

Table 46. MCS state for Q3N-3 (PW = 0.33 μs, PRR = 30,000/sec, DC = 1%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 18 19 20

60
Figure 53. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-4 (PW = 10 

μs, PRR = 10,000/sec, equivalent to PW = 100 μs, PRR = 1,000/sec, DC = 10%) interference.

Table 47. MCS state for Q3N-4 (PW = 10 μs, PRR = 10,000/sec, equivalent to PW = 100 μs, 

PRR = 1,000/sec), DC = 10%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-95 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-75 20 20 20

-70 20 20 20

-65 17 20 20

-60 18 18 20

-55 17 20 20

61
Figure 54. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-6 (PW = 3.3

μs, PRR = 30,303/sec, DC = 10%) interference.

Table 48. MCS state for Q3N-6 (PW = 3.3 μs, PRR = 30,303/sec, DC = 10%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-75 20 20 20

-70 20 20 20

-65 18 19 20

-60 18 18 20

-55 14 20 20

62
Figure 55. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-7 (PW = 10

μs, PRR = 20,000/sec, equivalent to PW = 200 μs, PRR = 1,000/sec, DC = 20%) interference.

Table 49. MCS state for Q3N-7 (PW = 10 μs, PRR = 20,000/sec, equivalent to PW = 200 μs, 

PRR = 1,000/sec, DC = 20%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-95 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-75 20 20 20

-70 20 20 20

-65 18 19 20

-60 18 18 20

-55 14 20 20

63
Figure 56. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-9 (PW = 6.6 

μs, PRR = 30,303/sec, DC = 20%) interference.

Table 50. MCS state for Q3N-9 (PW = 6.6 μs, PRR = 30,303/sec, DC = 20%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-70 19 20 20

-65 18 18 20

64
Figure 57. Data throughput, UE transmit (Tx) power, BLER, and RB usage for Q3N-10 (PW = 

10 μs, PRR = 30,000/sec, equivalent to PW = 300 μs, PRR = 1,000/sec, DC = 30%) interference.

Table 51. MCS state for Q3N-10 (PW = 10 μs, PRR = 30,000/sec, equivalent to PW = 300 μs, 

PRR = 1,000/sec, DC = 30%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-100 20 20 20

-95 20 20 20

-90 20 20 20

-85 20 20 20

-80 20 20 20

-75 20 20 20

-70 18 20 20

-65 18 18 20

-60 13 20 20

65
Figure 58. Data throughput, UE transmit (Tx) power, BLER, and RB usage for ECC-1/WFM-1

(PW = 4 μs, PRR = 1,000/sec, DC = 0.4%) interference.

Table 52. MCS state for ECC-1/WFM-1 (PW = 4 μs, PRR = 1,000/sec, DC = 0.4%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 20 20 20

66
Figure 59. Data throughput, UE transmit (Tx) power, BLER, and RB usage for ECC-2/WFM-2

(PW = 100 μs, PRR = 300/sec, DC = 3%) interference.

Table 53. MCS state for ECC-2/WFM-2 (PW = 100 μs, PRR = 300/sec, DC = 3%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-95 20 20 20

-85 20 20 20

-75 20 20 20

-65 20 20 20

-55 20 20 20

-45 20 20 20

-35 20 20 20

-25 17 20 20

67
Figure 60. Data throughput, UE transmit (Tx) power, BLER, and RB usage for TDWR/P0N-13 

(PW = 1 μs, PRR = 2,000/sec, DC = 3%) interference.

Table 54. MCS state for TDWR/P0N-13 (PW = 1 μs, PRR = 2,000/sec, DC = 3%) interference.

I

dBm

Transmit Channel 0

Min 

MCS

Most 

Frequent 

MCS

Max 

MCS

-70 20 20 20

-55 20 20 20

-40 20 20 20

-25 20 20 20

68
3.2.2 Burst Interference Testing

As noted previously, radar beams normally scan intermittently across fixed points in space. Burst 

interference testing replicated realistic radar-beam interference scenarios by injecting 20 pulses 

of radar interference every 5 seconds throughout the collection of diagnostic data. Figures 61–72

provide the results of the burst tests for the uplink. These graphs show how data throughput (top 

graph) and MCS (bottom graph) varied over time during the total duration of the data recording. 

For the uplink, only a single transmission channel was used. The two graphs in each figure are 

time synchronized based on timestamps contained in the diagnostic software data, the same way 

the burst data was synchronized for the downlink. The first timestamp in either the throughput 

data or the MCS data (whichever was started first) was used to determine the starting time of 

each graph. For all burst tests performed on the uplink, Ipeak = -25 dBm.

Figure 61. Data throughput and MCS state for P0N-1 interference.

69
Figure 62. Data throughput and MCS state for P0N-2 interference.

Figure 63. Data throughput and MCS state for P0N-5 interference.

70
Figure 64. Data throughput and MCS state for P0N-8 interference.

Figure 65. Data throughput and MCS state for P0N-10 interference.

71
Figure 66. Data throughput and MCS state for P0N-11 interference.

Figure 67. Data throughput and MCS state for Q3N-1 interference.

72
Figure 68. Data throughput and MCS state for Q3N-4 interference.

Figure 69. Data throughput and MCS state for Q3N-6 interference.

73
Figure 70. Data throughput and MCS state for Q3N-7 interference.

Figure 71. Data throughput and MCS state for Q3N-9 interference.

74
Figure 72. Data throughput and MCS state for Q3N-10 interference.

75
4 LTE EMISSION SPECTRUM MEASUREMENTS

4.1 LTE Emission Spectrum Measurement Procedure

While the authors had access to the LTE (FDD) prototype network during the course of the 

interference-effects measurements, they measured the emission spectrum of unfiltered LTE eNB

and UE transmitters. The measurements were performed, with a slight variation, in accord with 

the procedures of [8], by measuring using both peak and average detection. The measurement 

set-up is shown in Figure 73. The spectra were measured with approximately 60 dB of dynamic 

range for the eNB and 65 dB for the UE. Dynamic range was limited for these measurements due 

to configuration of the downlink and uplink RF paths between the eNB and UE which could not 

be altered. The RF path loss from the eNB output to the preselector input was approximately

50 dB, and the RF path loss from the UE output to the preselector input was approximately

53 dB.

Figure 73. System set-up for the LTE emission spectra measurements.

The standard wide-dynamic range measurement procedure of [8] was followed exactly for the 

peak-detected spectrum measurements, the key aspect of this procedure being that the 

measurement progressed as a stepped-frequency rather than a swept-frequency process, allowing 

for control of dynamic range during the measurement. For the average spectra, however, the 

procedure was varied slightly. To obtain the average spectra data points, the spectrum analyzer

collected 1,001 sample-detected points at each measured frequency in the spectrum. Then the 

linear-power root-mean-square (RMS) average of those 1,001 points was computed as the 

average emission spectrum power level at each frequency. Both the peak and average spectra 

76
were measured with a dwell interval of 300 ms per frequency data point. The measurement 

bandwidth of 30 kHz was selected in accordance with [9] for both eNB and UE spectra.

4.2 LTE eNB Emission Spectra

The emission spectrum structure of the LTE eNB transmitter, as measured with both peak and 

average detection, is shown in Figure 74. The spectrum is similar to WiMAX emission spectra 

presented in a recent NTIA Report [10], and another LTE eNB emission spectrum presented in 

[3], around the fundamental. Due to the limited dynamic range of these measurements, it is not 

possible to determine whether or not the eNB emission spectrum examined in this study exhibits 

the same flat “porch” seen in the previous LTE and WiMAX emission measurements. The 

“porch” observed in the previous measurements began leveling off at about -60 dB relative to the 

fundamental. It is also noted that the spectrum is from a prototype 3.5 GHz LTE eNB.

Figure 74. Peak-detected and average-detected LTE eNB emission spectra.

The spectra of other LTE eNBs, manufactured by other companies, may be assumed to generally 

look similar to Figure 74 around the fundamental. This is due to the fact that various existing

manufacturers use similar transmitter designs and they obtain their transmitter power amplifiers 

from a limited number of suppliers who are all working from the same current technology base.

There may, however, be differences in occupied bandwidth. For this FDD LTE network with 

77
10 MHz channel bandwidth, the emission bandwidth of the eNB transmission was 9 MHz. For 

the TDD LTE network previously examined [3], the occupied bandwidth was closer to 18 MHz. 

Comparable TDD and FDD LTE systems might both use 20 MHz of total spectrum. The TDD

LTE network would allocate that 20 MHz in a single spectrum channel carrying both eNB and 

UE data. The FDD LTE network would achieve the same performance by splitting the eNB and 

UE data across two spectrum channels of about 10 MHz each. 

The roll-off of the LTE eNB emission spectrum is shown in Figure 75. This spectrum was 

recorded with all the same parameters as the full eNB emission spectrum using average 

detection, except that a measurement bandwidth of 1 kHz was used. The number of samples over 

which the average power was computed (1,001) and the dwell time (300 ms) for each frequency 

point remained the same as in the full spectrum measurement.

Figure 75. Roll-off of LTE eNB emission spectrum.

4.3 LTE UE Emission Spectra

The emission spectrum structure of the LTE UE transmitter, as measured with both peak and 

average detection, is shown in Figure 76. While the UE transmission is centered at 

f0 = 3520 MHz, the lowest (in frequency) 10 RBs were unused, leaving only the upper 40 RBs 

78
active. Each RB is 180 kHz wide so the total occupied bandwidth of the emission spectrum of 

the UE is 7.2 MHz, causing the center of the intentional emissions to appear to be at 

3520.9 MHz. It should be noted that in the presence of interference, this spectrum can change 

dramatically as the UE changes the number of RBs in use. A change in RBs will change the total 

occupied bandwidth of the UE emission spectrum as:

BW = RB ∙ BWRB

where, BW is the total emission bandwidth, RB is the number of resource blocks in use, and 

BWRB is the bandwidth of a single resource block (180 kHz). The authors do not know how RBs 

are allocated in the presence of interference.

Figure 76. Peak-detected and average-detected LTE UE emission spectra.

79
5 SUMMARY AND CONCLUSIONS

5.1 Summary of Work and Results

The effects of radar interference on the performance of a prototype LTE (FDD) network have 

been assessed with a hardware test bed for a wide variety of radar waveforms. The parameters of 

the waveforms tested span the range of existing and likely future radar systems at 3.5 GHz. The 

LTE network that was tested is designed to be used as a micro-cell, but the test results are 

believed to likely be valid for other LTE systems. As a baseline, well-understood check on the

radar interference results, a 10 MHz wide Gaussian noise signal was also injected into the LTE 

receivers.

5.2 Radar Interference Impacts on LTE UE Receiver Performance (Downlink)

5.2.1 Continuous Interference Impacts

The impacts of continuous interference waveforms on data throughput and BLER for the 

downlink direction are shown in Figures 4–29. Tables 5–30 show how the MCS was affected by 

the coinciding interference waveforms. 

All P0N interference waveforms produced appreciable effects when interference, I, was greater 

than -65 dBm. Some Q3N waveforms degraded LTE performance when interference, I, 

was -85 dBm. The figures show that as the interference power level was increased, the 

interference impact increased. 

Regarding results for specific waveforms and trends, the simple pulsed waveforms (P0N and 

ECC) that caused the most loss of data throughput were ECC-2, P0N-2, P0N-5 through P0N-10,

and P0N-13, all resulting in throughput being reduced to 10 Mbps or less from a nominal 48 

Mbps. This level of degradation did not occur until interference power levels, I, were greater 

than -45 dBm. All of the P0N waveforms eventually caused some reduction in data throughput in 

the downlink. 

With respect to the chirped-pulsed (Q3N) waveforms, Q3N-1 through Q3N-3 and Q3N-9 caused 

the most reduction in data throughput, causing reductions to 10 Mbps or less from a nominal 48 

Mbps. For these interference waveforms, this level of degradation of throughput occurred when 

interference power levels, I, were greater than -55 dBm. It is noted that Q3N waveform impacts 

began at lower interference levels than for the P0N waveforms. Among the Q3N waveforms, 

Q3N-4 caused the least data throughput loss, but still reduced the throughput to approximately

21 Mbps at I = -60 dBm.

It is beyond the scope of this report to determine why particular waveforms had the most or least 

effects. NTIA welcomes LTE operators and other technical readers to review these data and 

share their views on these test results.

80
5.2.2 Off-Tuned Continuous Interference Impacts

One radar interference waveform, P0N-1, was tested with the center frequency of the radar 

interference offset from the eNB center frequency by 2 and 4 MHz. In both cases, the radar 

interference remained co-channel with the LTE system since it was still within the occupied 

bandwidth of the LTE eNB emission. Figures 6 and 7 show the effects of the 2 and 4 MHz offtune P0N-1 radar interference, respectively, on data throughput and BLER of the LTE downlink.

Tables 7 and 8 show how MCS was impacted by the coinciding off-tune interference. For the 

most part, the impact of the off-tune interference was very similar to that of the center-tuned 

interference (Figure 5, Table 6).

5.2.3 Burst Interference Impacts

Figures 30–36 show the impact of radar burst interference on data throughput and MCS for the 

downlink. All tested burst interference waveforms demonstrate some effect on the downlink 

throughput. The effect is observed as momentary, evenly-spaced (every 5 seconds) reductions in 

throughput. The Q3N-1 and Q3N-4 interference waveforms had the most instantaneous impact 

on data throughput. The Q3N-1 waveform resulted in brief throughput reductions of 2.5 Mbps 

typically, with one reduction of approximately 5 Mbps. For the Q3N-4 interference case, there 

was a momentary 6 to 7 Mbps reduction in throughput occurring every 20 seconds, or every 4th

radar burst, whilst other bursts resulted in momentary reductions of typically 1 Mbps.

Examining MCS, Q3N-4 and Q3N-10 were the only waveforms to exhibit an effect. This is 

observed as adjustments of the eNB MCS in 5 second intervals for both of these waveforms. No 

MCS changes were observed with other burst interference waveforms.

5.3 Radar Interference Impacts on LTE eNB Receiver Performance (Uplink)

5.3.1 Continuous Interference Impacts

For the uplink case, Figures 37–60 show how the interference waveforms impacted data 

throughput, UE transmit power, BLER, and RBs, and Tables 31–53 show how MCS was 

affected by the coinciding interference waveforms. 

The figures show that at least one of the four measured parameters (throughput, UE transmit 

power, BLER, and RB usage) were effected by increasing interference power. It is believed that 

since the UE was able to vary transmit power and RB usage, the uplink was more adaptable to 

interference than the downlink. 

Regarding results for specific waveforms and trends, the simple pulsed waveforms (P0N and 

ECC) that caused the most loss of data throughput were P0N-6, P0N-8 through P0N-10, and 

P0N-12, all resulting in throughput being reduced to less than 3 Mbps from a nominal 

12.5 Mbps. This level of degradation was not achieved until interference, I, was greater than -

40 dBm. Some waveforms exhibited little to no impact on data throughput at any tested 

81
interference levels. The figures also show that, at times, the LTE system mitigated the 

interference and maintained data throughput by adjusting UE transmit power and/or RBs.

With respect to the chirped-pulsed waveforms, Q3N-4, Q3N-6, Q3N-7 and Q3N-10 caused the 

most data throughput loss, degrading to 2.5 Mbps or less. Q3N-3 caused the least data 

throughput reduction, only reducing throughput to about 11 Mbps when the interference power 

level was -25 dBm.

As already noted, it is beyond the scope of this report to determine why particular waveforms had 

the most or least effects. NTIA welcomes LTE operators and other technical readers to review 

these data and share their views on these test results.

5.3.2 Burst Interference Impacts

Figures 61–72 show the effects of radar burst interference on data throughput and MCS for the 

uplink case. For all interference waveforms tested, MCS never changed. Furthermore, radar burst 

interference had no discernable effect on throughput at an interference level of -25 dBm.

5.4 Recommendations for Future Work

1. Theoretical analysis is recommended to better understand why various radar interference 

waveforms have the particular effects that have been published in this report. LTE signal 

detection needs to be understood to perform such analyses.

2. When commercial 3.5 GHz LTE equipment becomes available, LTE receivers should be 

tested to determine the non-linear effects of saturation and front-end overload from radar 

signals.

3. More emission spectra of LTE transmitters should be measured.

4. The impact of radar interference on an LTE network with multiple UEs should be 

investigated. 

5. Using data from this report and from the tasking described above, band sharing criteria need 

to be developed for spectrum sharing between 3.5 GHz radars and LTE systems.

82
6 REFERENCES

[1] Federal Communications Commission, “Proposal to Create a Citizen’s Broadband Service 

in the 3550-3650 MHz Band,” FCC Docket No. 12-354.

http://www.fcc.gov/document/enabling-innovative-small-cell-use-35-ghz-band-nprm-order

[2] Federal Communications Commission, “Amendment of the Commission’s Rules with 

Regard to Commercial operations in the 3550-3650 MHz Band,” FCC GN Docket No. 12-

354. http://apps.fcc.gov/ecfs/document/view?id=7521099242

[3] Sanders, F. H., J. E. Carroll, G. A. Sanders, and R. L. Sole, “Effects of Radar Interference 

on LTE Base Station Receiver Performance,” NTIA Technical Report TR-14-499, U.S. 

Dept. of Commerce, Dec. 2013. http://www.its.bldrdoc.gov/publications/2742.aspx

[4] U.S. Dept. of Commerce, National Telecommunications and Information Administration, 

“An Assessment of the Near-Term Viability of Accommodating Wireless Broadband 

Systems in the 1675-1710 MHz, 1755-1780 MHz, 3500-3650 MHz, 4200-4220 MHz and 

4380-4400 MHz Bands (President's Spectrum Plan Report),” NTIA, U.S. Dept. of 

Commerce, Nov. 2010. http://www.ntia.doc.gov/report/2010/assessment-near-termviability-accommodating-wireless-broadband-systems-1675-1710 MHz 17

[5] CEPT ECC Report 174, “Compatibility Between the Mobile Service in the Band 2500-

2690 MHz and the radiodetermination service in the band 2700-2900 MHz,” CEPT 

Electronic Communications Committee, Mar. 2012. 

http://www.erodocdb.dk/docs/doc98/official/Pdf/ECCRep174.pdf

[6] “LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures 

(3GPP TS 36.213 version 8.8.0 Release 8),” 3GPP, Section 7.2, October 2009.

http://www.etsi.org/deliver/etsi_ts/136200_136299/136213/08.08.00_60/ts_136213v08080

0p.pdf

[7] “TBS and MCS Signaling and Tables,” Motorola Submission to 3GPP, March 31, 2008. 

http://www.3gpp.org/ftp/tsg_ran/WG1_RL1/TSGR1_52b/Docs/R1-081638.zip

[8] Sanders, F. H., R. L. Hinkle and B. J. Ramsey, “Measurement Procedures for the Radar 

Spectrum Engineering Criteria (RSEC),” NTIA Technical Report TR-05-420, U.S. Dept. of 

Commerce, Mar. 2005. http://www.its.bldrdoc.gov/publications/2450.aspx

[9] ETSI TS 137 104 V11.2.1 Release 11, “Digital cellular telecommunications system (Phase 

2+); Universal Mobile Telecommunications System (UMTS); LTE; E-UTRA, UTRA and 

GSM/EDGE; Multi-Standard Radio (MSR) Base Station (BS) radio transmission and 

reception (3GPP TS 37.104 version 11.2.1 Release 11),” Oct. 2012.

http://www.etsi.org/deliver/etsi_ts/137100_137199/137104/11.02.01_60/ts_137104v11020

1p.pdf

[10] Sanders, F. H., R. L. Sole, J. E. Carroll, G. S. Secrest and T. Lynn Allmon, "Analysis and 

Resolution of RF Interference to Radars Operating in the Band 2700-2900 MHz from 

83
Broadband Communication Transmitters,” NTIA Technical Report TR-13-490, U.S. Dept. 

of Commerce, Oct. 2012. http://www.its.bldrdoc.gov/publications/2684.aspx

84
7 ACKNOWLEDGEMENTS

The authors would like to thank Durga Malladi, Yongbin Wei, Dean Brenner, Peter Gaal, 

Matthew Kwon, John Kuzin, and Rajeev Krishnamurthi for making this measurement possible. 

The authors would also like to thank Sam Liu and Awaiz Khan for traveling to Colorado and 

working with ITS engineers to perform this study. A final thank-you goes to Vishwanth Kamala 

Govindaraju and Awaiz Khan, again, for providing help to ITS during post-processing and 

analysis.

85
86
APPENDIX A: LTE TEST BED SYSTEM LOSSES

All losses in the LTE network for both the uplink and downlink were measured by ITS 

engineers, as shown in Figure A–1. The losses in the uplink and downlink RF paths as well as

the cable losses to monitoring and injection equipment were measured as follows:

• Uplink 

o Channel 0

 Interference injection port to analyzer monitoring port = 49.9 dB

 UE Tx port to analyzer monitoring port = 50.2 dB

 Interference injection port to eNB Rx port = 51.5 dB

 UE Tx port to eNB Rx port = 51.0 dB

o Channel 1

 Interference injection port to analyzer monitoring port = 50.0 dB

 UE Tx-0 port to analyzer monitoring port = 50.6 dB

 Interference injection port to eNB Rx port = 51.5 dB

 UE Tx port to eNB Rx port = 51.4 dB

• Downlink

o Channel 0

 Interference injection port to analyzer monitoring port = 20.3 dB

 eNB Tx port to analyzer monitoring port = 46.8 dB

 Interference injection port to UE Rx port = 21.7 dB

 eNB Tx port to UE Rx port = 48 dB

o Channel 1

 Interference injection port to analyzer monitoring port = 20.5 dB

 eNB Tx port to analyzer monitoring port = 42.0 dB

 Interference injection port to UE Rx port = 21.7 dB

 eNB Tx port to UE Rx port = 42.5 dB

• Cables

o From VSG to channel 0 interference injection port = 2.8 dB

o From VSG to channel 1 interference injection port = 3.5 dB

o Channels 0 and 1 analyzer monitoring port to spectrum analyzer = 0.7 dB

87
88

Figure A–1. Block diagram of the LTE network showing all the components in the RF path, interference injection points, and 

spectrum analyzer monitoring points.
APPENDIX B: COMPARISON FIGURES OF INTERFERENCE EFFECTS ON LTE 

(TDD) AND (FDD) UPLINKS

B.1 Notes on Comparison Figures of Interference Effects on LTE (TDD) and LTE (FDD) 

Uplinks

Figures from [3] showing the effects of interference into a TDD LTE uplink are reproduced here 

along with FDD LTE uplink throughput data (from this study) plotted as a function of S/(I+N)

for comparison. Some interference waveforms from this study were not used in [3] and vice 

versa. Only figures using the same interference waveform parameters are compared.

In order to facilitate comparison, the data throughput results presented in the figures of Section 

3.2.1 are now shown as a function of S/(I+N) (as opposed to only I); where S is the baseline

received signal power (with no interference), I is the interference power level, and N is the 

internal noise level of the receiver. The values of S, I, and N used to compute S/(I+N) to 

represent the data from this study are as follows:

• S = -85 dBm,

• N = -98.4 dBm,

• I = displayed interference power levels in the figures from Section 3.2.1. 

The baseline received desired signal of S = -85 dBm represents the nominal received signal 

power without interference from both studies. The internal inherent noise in the receiver is 

calculated to be -98.4 dBm in the 7.2 MHz bandwidth of the eNB receiver witha 7 dB noise 

figure. The value of S/I (in dB) was measured (as described in Section 2.3) and I, in the receiver, 

was calculated by subtracting S/I from the known value of S = -85 dBm for the uplink baseline 

condition (with no interference). 

It is noted that these are distinctly different tests. The system in the [3] was a 20 MHz wide TDD 

macro-cell uplink without any UE transmit power or RB control. The system described in this 

report was a roughly 10 MHz wide FDD micro-cell uplink that was able to employ UE transmit 

power (thereby changing the value of S) and RB control. In [3], the allowable uplink BLER was 

set to 10% and for this study it was set to 30%. The TDD system in [3] used a channel emulator 

(frequency-selective multipath) between the UE and eNB whereas the system examined in this 

study did not. Finally, the noise figure of the TDD system in [3] was measured to be 3 dB 

whereas in the FDD system it was reported by the industry participant as 7 dB.

When comparing the throughput results for the TDD and FDD uplinks, the general trend of 

decreasing throughput as S/(I+N) decreases is observed for both systems for the majority of the 

interference waveforms. However, significant differences in degradation behavior are observed. 

Compared to the TDD uplink, the FDD LTE uplink examined in this study had substantially 

more flexibility in mitigating interference effects through the use of UE power control and the 

ability to reduce RB usage, thereby providing more power to the remaining available RBs. The 

relatively robust behavior of the FDD LTE uplink compared to the TDD uplink is likely 

explained by these dynamic capabilities. There were only two interference waveforms, P0N-7 

and P0N-11, where the TDD system appears to be more capable of handling the respective 

interference waveforms.

89
B.2 Comparison Figures from the Two LTE Uplinks

Figure B–1. Throughput and eNB Noise Floor for LTE (TDD) network for 20 MHz wide 

Gaussian noise interference (covering full LTE bandwidth). 

Figure B–2. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for 10 MHz 

wide Gaussian noise interference (covering full LTE bandwidth).

90
Figure B–3. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-1 interference.

Figure B–4. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-1 

interference.

91
Figure B–5. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-2 interference.

Figure B–6. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-2 

interference.

92
Figure B–7. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-3 interference.

Figure B–8. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-3 

interference.

93
Figure B–9. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-4 interference.

Figure B–10. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-4 

interference.

94
Figure B–11. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-5 interference.

Figure B–12. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-5 

interference.

95
Figure B–13. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-6 interference.

Figure B–14. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-6 

interference.

96
Figure B–15. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-7 interference.

Figure B–16. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-7 

interference.

97
Figure B–17. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-8 interference.

Figure B–18. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-8 

interference.

98
Figure B–19. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-9 interference.

Figure B–20. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-9 

interference.

99
Figure B–21. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-10 

interference.

Figure B–22. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-10 

interference.

100
Figure B–23. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-11 

interference.

Figure B–24. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-11 

interference.

101
Figure B–25. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-12 

interference.

Figure B–26. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N-12 

interference.

102
Figure B–27. Throughput and eNB Noise Floor for LTE (TDD) network for P0N-13/TDWR

interference.

Figure B–28. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for P0N13/TDWR interference.

103
Figure B–29. Throughput and eNB Noise Floor for LTE (TDD) network for ECC-1/WFM-1 

interference.

Figure B–30. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for ECC1/WFM-1 interference.

104
Figure B–31. Throughput and eNB Noise Floor for LTE (TDD) network for ECC-2/WFM-2 

interference.

Figure B–32. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for ECC2/WFM-2 interference.

105
Figure B–33. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-1 interference.

Figure B–34. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-1 

interference.

106
Figure B–35. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-2 interference.

Figure B–36. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-2 

interference.

107
Figure B–37. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-3 interference.

Figure B–38. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-3 

interference.

108
Figure B–39. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-5 interference.

Figure B–40. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-4 

interference (Q3N-4 waveform parameters are the same as Q3N-5 in previous study).

109
Figure B–41. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-6 interference.

Figure B–42. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-6 

interference.

110
Figure B–43. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-9 interference.

Figure B–44. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-9 

interference.

111
Figure B–45. Throughput and eNB Noise Floor for LTE (TDD) network for Q3N-12 

interference.

Figure B–46. Throughput, UE Tx power, BLER, and RBs for LTE (FDD) network for Q3N-10 

interference (Q3N-10 waveform parameters are the same as Q3N-12 in previous study).

112
FORM NTIA-29 U.S. DEPARTMENT OF COMMERCE 

(4-80) NAT’L. TELECOMMUNICATIONS AND INFORMATION ADMINISTRATION

BIBLIOGRAPHIC DATA SHEET

1. PUBLICATION NO.

TR-14-506

2. Government Accession No. 3. Recipient’s Accession No.

4. TITLE AND SUBTITLE

Effects of Radar Interference on LTE (FDD) eNodeB and UE Receiver Performance in 

the 3.5 GHz Band

5. Publication Date

July 2014

6. Performing Organization Code

NTIA ITS.T/NTIA OSM

7. AUTHOR(S)

Geoffrey A. Sanders, John E. Carroll, Frank H. Sanders, Robert L. Sole

9. Project/Task/Work Unit No.

8. PERFORMING ORGANIZATION NAME AND ADDRESS 6469000-200

Institute for Telecommunication Sciences

National Telecommunications & Information Administration

U.S. Department of Commerce

325 Broadway

Boulder, CO 80305

10. Contract/Grant Number.

11. Sponsoring Organization Name and Address

National Telecommunications & Information Administration

Herbert C. Hoover Building

14th & Constitution Ave., NW

Washington, DC 20230

12. Type of Report and Period Covered

14. SUPPLEMENTARY NOTES

15. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant bibliography or 

literature survey, mention it here.)

In response to proposals to introduce new radio systems into the 3550 – 3650 MHz radio spectrum in the United States, the 

authors have performed measurements and analysis on effects of interference, from a variety of radar waveforms, to the 

performance of a prototype 3.5 GHz Long Term Evolution (LTE) network, consisting of one base station (known as an 

eNodeB) and one client (referred to as user equipment or UE) utilizing frequency-division duplexing (FDD). This work has 

been prompted by the possibility that LTE receivers may eventually share spectrum with radar operations in this spectrum 

range. Radar pulse parameters used in this testing spanned the range of both existing and anticipated future radar systems in

the 3100 – 3650 MHz spectrum range. Effects of radar interference on the LTE uplink and downlink throughput, BLER, and 

modulation coding scheme (MCS) were measured. Additionally, for the uplink tests, resource block (RB) usage and UE 

transmit power were recorded. Effects on LTE performance are presented as a function of radar pulse parameters and the 

incident power level of radar pulses into the LTE receivers. The authors do not determine the interference protection criterion 

for nominal LTE network performance. Rather, the data presented can be used by spectrum managers and engineers as a 

building block in the construction of frequency-and-distance separation requirements for radar transmitters and LTE 

receivers, supporting possible future spectrum sharing at 3.5 GHz.

16. Key Words (Alphabetical order, separated by semicolons)

Block error rate (BLER); chirped pulses; Long Term Evolution (LTE); P0N pulses; radar; spectrum sharing; frequencydivision duplexing (FDD); evolved-Node B (eNB); Q3N pulses

17. AVAILABILITY STATEMENT

UNLIMITED.

FOR OFFICIAL DISTRIBUTION.

18. Security Class. (This report)

Unclassified

20. Number of pages

141

19. Security Class. (This page)

Unclassified

21. Price:

n/a

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