Combined turbo equalisation and block turbo coded modulation

A Block Turbo Equalizer Scheme

“…III. SPC-TPC CODES APLIED TO CONVENTIONAL TURBO EQUALIZATION AND TURBO DECODING Before presenting the new turbo equalizer proposed here, the SPC-TPC code will be adapted to the conventional scheme of turbo equalization and turbo decoding used in [4], [7] and [6]. The communication system is depicted in Figure 1.…”

“…In the equalizer block, the use of algorithms with reduced complexity represents a challenging research effort in itself [3] [5]. The use of block turbo codes in the turbo equalization process seems to be less investigated [6] [7]. In these references, the channel decoding block uses the turbo decoding process described in [8] for decoding a BCH-based parallel-concatenated scheme and a BCH-based two-dimensional product code, respectively.…”

“…In these references, the channel decoding block uses the turbo decoding process described in [8] for decoding a BCH-based parallel-concatenated scheme and a BCH-based two-dimensional product code, respectively. In [6] and [7], one turbo decoding iteration is performed for each turbo equalizer iteration.…”

“…In this paper, a block turbo code is used in the channeldecoding block. However, instead of waiting for the end of a complete iteration of the turbo decoding process, only one dimension of a D-dimensional SPC-TPC is decoded at each iteration of the turbo equalization process, the complexity of such scheme being reduced, if compared to the block turbo equalizers analyzed in [6] and [7]. Furthermore, the delay of this process can be reduced in comparison to the case in which there is a complete iteration in the turbo decoding process per turbo equalizer iteration.…”

Iterative Equalization and Decoding Scheme for Underwater Acoustic Coherent Communications

“…It isn't suit for the underwater acoustic channel with long delay spreads. In the structure of iterative euqalization and decoding, equalizer can use ADFE (Choi, 2008;Noorbakhsh et al, 2003) or equalizer based on channel estimation (Flanagan & Fagan, 2007;Otnes & Tuchler, 2004;Tuchler et al, 2002). For underwater acoustic channel with severely mutipath propagation and large time delay, adptive channel tracking can get better performance than channel estimation using trainning sequence or pilot symbols.…”