Design and measurement-based evaluations of coherent JT CoMP: a study of precoding, user grouping and resource allocation using predicted CSI

EURASIP Journal on Wireless Communications and Networking

Table 2 Prediction performance

ϑ	$σ_{n}^{2}$	Predicted channels		Outdated CSIT
	(dBm)	NMSE all	NMSE for weakest	NMSE all BS (dB)
		BS (dB)	BS (dB)
0	-110	-17.8	-7.1	-17.8
	-120	-23.9	-12.7	-23.9
	-130	-30.9	-20.0	-30.9
4	-110	-12.8	-5.9	-10.5
	-120	-15.3	-9.4	-12.5
	-130	-17.6	-13.3	-14.0
8	-110	-11.0	-4.8	-6.9
	-120	-12.9	-7.4	-7.9
	-130	-14.8	-10.3	-8.6
12	-110	-9.6	-4.0	-4.4
	-120	-11.2	-5.9	-5.0
	-130	-12.8	-8.2	-5.3
18	-110	-7.9	-3.0	-1.8
	-120	-9.2	-4.1	-2.1
	-130	-10.3	-5.4	-2.2

The average over all measurement locations and all subcarriers of the NMSE for prediction horizons of ϑ = 0 (filter estimate), 4, 8, 12 and 18 RS samples in time or 0, 0.06, 0.13, 0.19 and 0.28 λ in space, for the three noise levels. Results are averaged in decibels over all base stations (third column) and the weakest base station only (fourth column). Fifth column: the NMSE when using outdated estimates.