D.4 Birth-Death propagation conditions

25.1413GPPBase Station (BS) conformance testing (FDD)Release 17TS

The dynamic propagation conditions for the test of the baseband performance is a non fading propagation channel with two taps. The birth-death propagation condition has two taps, Path1 and Path2 which alternate between ‘birth’ and ‘death’. The positions the paths appear are randomly selected with an equal probability rate and is shown in figure D.2. For BS with receiver diversity, the same path positions shall be applied to both receiver antenna connectors, and the path switching times shall be synchronized on the two receiver antenna connectors, but the AWGN signals applied to the two receiver antenna connectors shall be uncorrelated.

Figure D.2: Birth death propagation sequence

1. Two paths, Path1 and Path2 are randomly selected from the group [-5, -4, -3, -2, -1, 0 ,1, 2, 3, 4, 5] μs. The paths have equal magnitudes and equal phases.

2. After 191 ms, Path1 vanishes and reappears immediately at a new location randomly selected from the group [-5, -4, -3, -2, -1, 0 ,1, 2, 3, 4, 5] μs but excludes the point Path2. The magnitudes and the phases of the tap coefficients of Path 1 and Path 2 shall remain unaltered.

3. After an additional 191 ms, Path2 vanishes and reappears immediately at a new location randomly selected from the group [-5, -4, -3, -2, -1, 0 ,1, 2, 3, 4, 5] μs but excludes the point Path1. The magnitudes and the phases of the tap coefficients of Path 1 and Path 2 shall remain unaltered.

4. The sequence in 2) and 3) is repeated.

D.4A High speed train conditions

High speed train conditions are as follows:

Scenario 1: Open space

Scenario 2: Tunnel with leaky cable

Scenario 3: Tunnel for multi-antennas

The high speed train conditions for the test of the baseband performance are 2 non fading propagation channels (scenario 1 and 3) and 1 fading propagation channel (scenario 2) with one tap. For BS with Rx diversity defined in scenario 1, the Doppler shift variation is the same between antennas.

For scenario 1 and 3, Doppler shift is given by

(D.2)

where is the Doppler shift and is the maximum Doppler frequency. The cosine of angle is given by

, (D.3)

, (D.4)

, (D.5)

where is the initial distance of the train from BS, and is BS-Railway track distance, both in meters; is the velocity of the train in m/s, is time in seconds.

For scenario 2, Rician fading is considered where Rician factor, K is defined as the ratio between the dominant signal power and the variant of the other weaker signals.

Doppler shift and cosine angle is given by equation D.2 and D.3-D.5 respectively, where the required input parameters listed in table D.2A and the resulting Doppler shift shown in Figure D.3 and D.4 are applied for all frequency bands.

Table D.2A: Parameters for high speed train conditions

Parameter	Value
	Scenario 1	Scenario 2	Scenario 3
	1000 m	Infinity	300 m
	50 m	–	2 m
K	–	10 dB	–
	350 km/h	300 km/h	300 km/h
	1340 Hz	1150 Hz	1150 Hz

NOTE1: Parameters for HST conditions in table D.2A including and Doppler shift trajectories presented on figures D.3 and D.4 were derived for Band1.

Figure D.3: Doppler shift trajectory for scenario 1

Figure D.4: Doppler shift trajectory for scenario 3