Overview and comparison of equalization schemes for space-time-coded signals with application to EDGE

This paper describes and compares several practical equalization schemes for space-time-coded transmissions over broadband wireless channels. For space-time trellis codes (STTCs), we describe and compare two reduced-complexity trellis-based joint equalization and decoding schemes whose performance is further optimized by a front-end finite-impulse response (FIR) channel-shortening prefilter. For space-time block codes, we describe and compare three joint equalization and decoding schemes based on a block-level implementation of the well-known Alamouti scheme either in the time or frequency domains. We consider the third-generation time division multiple access (TDMA) cellular system known as Enhanced Data rates for Global Evolution (EDGE) and recommend a promising equalization scheme for space-time trellis-coded and for Alamouti-type space-time block-coded dual-antenna transmissions based on simulation results for typical urban channel conditions where the delay spread is few symbol periods.