Title :
Analysis of hybrid selection/maximal-ratio combining of diversity branches with unequal SNR in Rayleigh fading
Author :
Win, Moe Z. ; Winters, Jack H.
Author_Institution :
Wireless Syst. Res. Dept., AT&T Lab.-Res., Red Bank, NJ, USA
Abstract :
The performance of a hybrid selection/maximal-ratio combining (H-S/MRC) diversity system in multipath fading environment is analyzed. With H-S/MRC, L out of N diversity branches are selected and combined using maximal-ratio combining (MRC). This technique provides improved performance over L branch MRC when additional diversity is available, without requiring additional resources (i.e., power consumption, RF electronics). In particular, we consider independent Rayleigh fading on each diversity branch without assuming equal signal-to-noise ratio (SNR) averaged over the fading. We analyze this system using a “virtual branch” technique which results in a simple derivation and formula for the mean of the combiner output SNR for any L and N. We further obtain the symbol error probability (SEP) for coherent reception of M-ary phase-shift keying (MPSK) and quadrature amplitude modulation (MQAM)
Keywords :
Rayleigh channels; diversity reception; error statistics; multipath channels; personal communication networks; phase shift keying; quadrature amplitude modulation; M-ary phase-shift keying; M-ary quadrature amplitude modulation; MPSK; MQAM; PCS band; RF electronics; Rayleigh fading; SNR; coherent reception; combiner output SNR; diversity branches; hybrid selection/maximal-ratio combining; independent Rayleigh fading; multipath fading environment; performance; power consumption; signal-to-noise ratio; symbol error probability; unequal SNR; virtual branch; Bit error rate; Diversity reception; Energy consumption; Error probability; Fading; Lifting equipment; Performance analysis; Radio frequency; Rayleigh channels; Telephone sets;
Conference_Titel :
Vehicular Technology Conference, 1999 IEEE 49th
Conference_Location :
Houston, TX
Print_ISBN :
0-7803-5565-2
DOI :
10.1109/VETEC.1999.778049