3GPP FDD Base Station Tests with Signal Generators and Analyzers

Transcription

1 3GPP FDD Base Station Tests with Signal Generators and Analyzers 1GPP-Dq 04/02 1 3GPP tests with SMIQ

2 Agenda to TS Adjacent channel selectivity 1GPP-Dq 04/02 2

3 Base stations Multi standard base station (software radio) higher bandwidth better dynamic range 1GPP-Dq 04/02 3

4 Base stations Multi standard base station (software radio) higher bandwidth better dynamic range 1GPP-Dq 04/02 4

5 Measurement equipment Stronger requirements on physical performance use general-purpose instruments (spectrum analyzers and signal generators) functional tests required general-purpose instruments need more functionality 1GPP-Dq 04/02 5

6 3GPP FDD Base TS Transmitter tests can be done with general-purpose instruments (spectrum analyzers and signal generators) 1GPP-Dq 04/02 6

7 Transmitter tests - test setup Base station under test RX SMIQ generates 3GPP signal with TPC field information FSIQ measures code domain power in transmitted signal by the base station TX 1GPP-Dq 04/02 7

8 Power control steps Base station sends test model 2 signal and reacts on TPC field information by the up link signal generator Two tests Accuracy of 1 db power step has to be ±0.5 db optional: accuracy of 0.5 db power steps has to be ± 0.25 db Accuracy of 10 consecutive equal commands (up or down) has to be ±2 db for a 1 db step size (±1 db for 0.5 db steps) 1GPP-Dq 04/02 8

9 Power control dynamic range Base station sends test model 2 signal Max. power for DPCH under test should be greater than P max -3 db Uplink signal generator sends consecutive 0 s to drive the code channel power to the minimum level which shall be less than P max - 28 db 1GPP-Dq 04/02 9

10 Base to TS as defined in the standard Reference sensitivity level Dynamic range Adjacent channel selectivity Blocking characteristics Intermodulation characteristics Verification of the internal BER calculation 1GPP-Dq 04/02 10

11 Test setup Demodulation of a DPCH in presence of various interferers Wanted 3GPP signal uplink reference measurement channel (12.2 kbps) Interfering signal 3GPP or CW signal Receiver demodulates reference measurement channel Bit error rate (BER) is measured as a function of signal-to-interferer ratio 1GPP-Dq 04/02 11

12 Test setup RF 2 SMIQ 2 generating interfering 3GPP signal BERT Demodulated and decoded PRBS Data RF 1 Power combiner RF = RF 1 + RF 2 + RF 3 DUT SMIQ 1 generating wanted 3GPP signal SMR or SMP generating interfering CW signal RF 3 1GPP-Dq 04/02 12

13 Adjacent channel selectivity Uplink signal generator sends 12.2 kbps DPCH with reference measurement channel Apply interfering 3GPP signal Measure BER P 3GPP interferer wanted 3GPP signal 63 db f f 0 f MHz 1GPP-Dq 04/02 13

14 Base to TS as defined in the standard Demodulation in static propagation conditions Demodulation of DCH in multipath fading conditions Demodulation of DCH in moving propagation conditions Demodulation of DCH in birth/death propagation conditions Verification of the internal BLER calculation 1GPP-Dq 04/02 14

15 Test setup Demodulation of a DPCH in various propagation conditions Wanted 3GPP signal uplink reference measurement channel Signal is generated in different propagation conditions static propagation conditions (without Fading) multipath fading moving propagation birth-death propagation White Gaussian noise is added Receiver demodulates reference measurement channel Block error rate (BLER) is measured as a function of signal-to-noise ratio 1GPP-Dq 04/02 15

16 Test setup with receiver antenna diversity 1GPP-Dq 04/02 16

17 Test setup with receiver antenna diversity I/Q out Base station under test RX A SMIQ 1 generating wanted 3GPP signal with fading and AWGN I/Q SMIQ 2 adds fading and AWGN to I/Q signal received from 1st SMIQ I/Q in RX B 1GPP-Dq 04/02 17

18 Demodulation of DCH in multipath fading conditions The table shows the propagation conditions that are used for the performance measurements in multi-path fading environment. All taps have classical Doppler spectrum. 1GPP-Dq 04/02 18

19 Demodulation of DCH in moving propagation conditions The dynamic propagation conditions for the test of the baseband performance are non fading channel models with two taps. The taps have equal strengths and equal phases The moving propagation condition has two tap, one static, Path 0, and one moving, Path 1. The time difference between the two paths is according to P 0 P 1 τ t 0 t 1 1GPP-Dq 04/02 19

20 Demodulation of DCH in birth/death propagation conditions The dynamic propagation conditions for the test of the baseband performance is a non fading propagation channel with two taps. The moving propagation condition has two taps, Path 1 and Path 2 which alternate between 'birth' and 'death'. The positions the paths appear are randomly selected with an equal probability rate P1 P2 P1 P1 P2 P2 P1 P GPP-Dq 04/02 20

21 3GPP FDD BS tests (TS ) can be done with spectrum analyzers and signal generators Strong functional requirements on measurement equipment In the future: higher demand on physical performance (bandwidth, dynamic range) 1GPP-Dq 04/02 21