1. www.bundesnetzagentur.de Compatibility measurements UMTS/LTE/GSM -> GSM-R Thomas Hasenpusch Federal Network Agency, Germany CG-GSM-R(13)033

2. 2 Motivation / Aims Frequency planning in Europe: What happens to the GSM-R terminal receivers when facing UMTS/LTE in the public mobile band above 925 MHz? GSM-R compatibility measurements (BnetzA Germany)02.10.2016

3. 3 Interference Mechanisms (1) Unwanted emissions from UMTS/LTE in the GSM-R channel A f 925 MHz GSM-R channel GSM-R compatibility measurements (BnetzA Germany)02.10.2016

4. 4 Interference Mechanisms (2) Receiver blocking due to high input powers A f Min. S/N Max. mixer power GSM-R compatibility measurements (BnetzA Germany)02.10.2016

5. 5 Interference Mechanisms (3) Receiver intermodulation (2 narrowband signals) A f GSM-R channel f1f1 f2f2 f IM f IM = 2*f 1 -f 2 GSM-R compatibility measurements (BnetzA Germany)02.10.2016

6. 6 Interference Mechanisms (4) Receiver intermodulation (1 wideband signal) 921.2MHz 924.8MHz UMTS GSM UMTS signal IM products (all) IM frequencies involved when GSM-R frequency is 921.2 MHz IM frequencies involved when GSM-R frequency is 924.8 MHz GSM-R compatibility measurements (BnetzA Germany)02.10.2016

7. 7 Interfering GSM Signals GSM-R compatibility measurements (BnetzA Germany)02.10.2016

8. 8 Interfering UMTS signals GSM-R compatibility measurements (BnetzA Germany)02.10.2016

9. 9 Interfering LTE/5MHz signals GSM-R compatibility measurements (BnetzA Germany)02.10.2016

10. 10 Receiver Selection Rx1 „improved“: Receiver with highly linear front- end, improved filter and AGC, exceeding requirements of ETSI TS 102 933 Rx2 „standard“: Receiver representing equipment currently used in trains, meeting requirements of ETSI EN 300 910 V8.5.1 and ETSI TS 145 005 V8.16 GSM-R compatibility measurements (BnetzA Germany)02.10.2016

11. 11 Failure Criterion The GSM-R link was regarded interfered when the RxQual value reported by the terminal receiver dropped to 4 or less. Measured with CMU200 base station tester. GSM-R compatibility measurements (BnetzA Germany)02.10.2016

12. 12 Measurement of Receiver Characteristics Sensitivity of both receivers: -107 to -108 dBm Selectivity (measured with unmodulated carrier): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

13. 13 C/I from Unwanted Emissions Measurement setup: GSM-R base station emulator CMU200 10 dB GSM-R receiver (DUT) M downlink uplink Rx Tx Circulator (10) Directional coupler 20 dB 50 dB Signal generator Interfering signal 6-60 dB GSM-R signal level: -101 dBm and -98 dBm GSM-R compatibility measurements (BnetzA Germany)02.10.2016

14. 14 C/I from Unwanted Emissions Measurement results for standard interferers: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

15. 15 C/I from Unwanted Emissions Measurement results for realistic interferers: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

16. 16 C/I Using Blocking Test Setup: Measurement setup: GSM-R base station emulator CMU200 10 dB GSM-R receiver (DUT) M downlink uplink Rx Tx Circulator Directional coupler 20 dB 50 dB Signal generator Interfering signal 6-60 dBBand pass GSM-R frequencies 924.8 MHz and 921.2 MHz GSM-R signal levels between -101 and -35 dBm 3 different interfering frequencies, but always high offset GSM-R compatibility measurements (BnetzA Germany)02.10.2016

17. 17 C/I Using Blocking Test Setup Measurement results for GSM interferer: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

18. 18 C/I Using Blocking Test Setup Measurement results for broadband interferer: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

19. 19 C/I Using Intermodulation Test Setup Measurement setup: GSM-R base station emulator CMU200 10 dB GSM-R receiver (DUT) M downlink uplink Rx Tx Circulator (10) Directional coupler 20 dB 50 dB Signal generator 1 Interfering signal 6-60 dBBand pass Signal generator 2 + 50 Ω GSM-R compatibility measurements (BnetzA Germany)02.10.2016

20. 20 C/I Using Intermodulation Test Setup Frequency combinations: Signal 1Signal 2 CombinationSystemFrequency f 1 SystemFrequency f 2 1GSM935,0 MHzGSM948,8 MHz 2GSM935,0 MHzUMTS947,5 MHz 3UMTS937,5 MHzGSM953,8 MHz 4LTE/10MHz935,0 MHzUMTS942,5 MHz 5UMTS937,5 MHzUMTS952,5 MHz 6GSM927,4 MHzUMTS932,5 MHz GSM-R compatibility measurements (BnetzA Germany)02.10.2016

21. 21 C/I Using Intermodulation Test Setup Measurement results GSM-R compatibility measurements (BnetzA Germany)02.10.2016

22. 22 Combination of Results One single GSM interferer GSM-R compatibility measurements (BnetzA Germany)02.10.2016

23. 23 Combination of Results One UMTS interferer: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

24. 24 Combination of Results One LTE/5MHz interferer: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

25. 25 Combination of Results Two or more GSM interferers: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

26. 26 Combination of Results UMTS interferer plus UMTS/GSM interferer: GSM-R compatibility measurements (BnetzA Germany)02.10.2016

27. 27 Result Evaluation (1) At low GSM-R levels unwanted emissions dominate, at higher GSM-R levels receiver overloading dominates. Transition between interference effects strongly depends on interfering signal quality: Realistic signals have much less interference potential from unwanted emissions than signals just meeting the standard. The interference potential of UMTS and LTE/5MHz is nearly equal. Interference potential due to unwanted emissions from UMTS/LTE is about 10-20 dB higher than from GSM. One UMTS/LTE signal alone may create receiver intermodulation often affecting the whole GSM-R band. GSM-R compatibility measurements (BnetzA Germany)02.10.2016

28. 28 Additional Measurements with Filters Necessary to assess: GSM-R on upper channels, UMTS/LTE in first 5MHz of public band (critical situations) Improvements by different receiver filter solutions Receiver configurations: Rx1: „improved“ Rx2: „standard“ Rx3: „standard“ receiver plus dual 8-cavity Kaelus filter Rx4: „improved“ receiver plus small Lorch filter GSM-R compatibility measurements (BnetzA Germany)02.10.2016

29. 29 Additional Measurements with Filters Filter response dual 8-cavity Kaelus (1): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

30. 30 Additional Measurements with Filters Filter response dual 8-cavity Kaelus (2): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

31. 31 Additional Measurements with Filters Filter response low pass Lorch (1): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

32. 32 Additional Measurements with Filters Filter response low pass Lorch (2): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

33. 33 Additional Measurements with Filters Measurement setup: GSM-R base station emulator CMU200 10 dB GSM-R receiver (DUT) incl. filter for Rx3 and Rx4 M downlink uplink Rx Tx Circulator (10) Directional coupler 20 dB 50 dB Signal generator SMU200A Interfering signal GSM-R frequencies 924.8 MHz and 924.2 MHz GSM-R levels from -101 dBm to -31 dBm Interfering frequencies 927.6 MHz and 932.6 MHz (UMTS/LTE) and 925.2 MHz (GSM) GSM-R compatibility measurements (BnetzA Germany)02.10.2016

34. 34 Additional Measurements with Filters Result example (realistic broadband interferer): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

35. 35 Additional Measurements with Filters Result example (standard broadband interferer): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

36. 36 Additional Measurements with Filters Result example (realistic interferer on 932.6 MHz): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

37. 37 Additional Measurements with Filters Result example (standard interferer on 932.6 MHz): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

38. 38 Additional Measurements with Filters Result example (realistic interferer vs. channel 970): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

39. 39 Additional Measurements with Filters Result example (standard interferer vs. channel 970): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

40. 40 Additional Measurements with Filters Result example (GSM realistic interferer): GSM-R compatibility measurements (BnetzA Germany)02.10.2016

41. 41 Additional Measurements with Filters Transition levels from unwanted emissions to overloading effects InterfererRx1 (improved) Rx2 (standard) Rx3 (standard with Kaelus filter) Rx4 (improved with Lorch filter) UMTS realistic on 927.6 MHz -80 dBm-100 dBmnever *)-80 dBm LTE realistic on 927.6 MHz -85 dBm-98 dBmnever *)-85 dBm UMTS standard on 927.6 MHz -48 dBm-72 dBmnever *)-45 dBm LTE standard on 927.6 MHz -52 dBm-78 dBmnever *)-50 dBm UMTS realistic on 932.6 MHz never *)-100 dBmnever *)- LTE realistic on 932.6 MHz never *)-100 dBmnever *)- UMTS standard on 932.6 MHz never *)-85 dBmnever *)- LTE standard on 932.6 MHz never *)-90 dBmnever *)- GSM realistic on 925.2 MHz -90 dBm-80 dBm -88 dBm GSM standard on 925.2 MHz -85 dBm-75 dBm-72 dBm-82 dBm *) never = not overloaded up to about +10 dBm GSM-R compatibility measurements (BnetzA Germany)02.10.2016

42. 42 Result Evaluation (2) The standard receiver is nearly always overloaded by UMTS/LTE in the first 5 MHz of the public mobile band. The improved receiver is only overloaded when UMTS/LTE is on 927.6 MHz and the GSM-R level is high (>80dBm for realistic, >50dBm for standard signals), and then the tolerable interference level is up to 20 dB higher than for the standard receiver. Receivers with the Kaelus filter are never overloaded by UMTS/LTE signals. The additional Lorch filter for the improved receiver does not further increase immunity against UMTS/LTE on 927.6 MHz. GSM-R compatibility measurements (BnetzA Germany)02.10.2016

43. www.bundesnetzagentur.de Compatibility measurements UMTS/LTE/GSM -> GSM-R Thomas Hasenpusch Federal Network Agency, Germany / ECC Thank you for your attention!