Analysis on forward link pilot ratio for DS-CDMA under correlated Rician fading
Wen-Yi Kuo · 2002
In the forward link of many CDMA systems, a common pilot channel (shared by all users) is employed to provide the reference for coherent demodulation. A higher pilot ratio yields a good channel estimate but takes away some capacity from traffic users while a lower pilot ratio results in a higher traffic power need per user. This paper analyzes this trade-off by deriving the analytical error performance which includes (1) the imperfect channel estimation by pilot channel and (2) a very general channel model where correlation between paths as well as Rician fading (ranges from Rayleigh to AWGN) is considered. The effect of the interference pattern from different base stations is also evaluated.