Chapter 17
Iterative Channel Estimation and Multi-stream Detection for SDM-OFDM
17.1 Iterative Signal Processing
Despite the immense interest of both the academic and the industrial research communities, the conception of a practical multiple-input, multiple-output (MIMO) transceiver architecture which is capable of approaching the MIMO channel’s capacity in realistic channel conditions remains largely an open problem. An important overview encompassing most major aspects of broadband MIMOOFDM wireless communications including both channel estimation and signal detection, as well as time- and frequency-domain synchronization, was contributed by Stüber et al. [295]. Other important publications considering MIMO systems operating in realistic channel conditions include those by Münster and Hanzo [297], Li et al. [294],Mai et al. as well as Qiao et al. [308]. Nevertheless, substantial contributions addressing all the major issues pertaining to the design of MIMO transceivers, namely error correction, space–time detection and channel estimation, in realistic channel conditions remain scarce.
Against this background, in this chapter we introduce an iterative, so-called turbo Multi-Antenna, Multi-Carrier (MAMC) receiver architecture. Our turbo receiver is illustrated in Figure 17.1. Following the philosophy of turbo processing [314], our turbo SDM-OFDM receiver comprises a succession of detection modules which iteratively exchange soft-bit-related information and thus facilitate a substantial ...
