An efficient finite precision realization of the block adaptive decision feedback equalizer

Recently, a block based adaptive decision feedback equalizer (ADFE) is presented which first uses an iterative scheme to evaluate a block of unknown decisions. FFT based block processing is then used on the received input block and the decision block to carry out the block ADFE operation. A direct floating point (FP) based realization of this scheme, however, pushes up the cost and complexity of processing hugely, as each FP operation involves several additional steps not present in its fixed point (FxP) counterpart. To overcome this problem, a block floating point (BFP) based treatment is presented in this paper for realization of the block ADFE. The proposed scheme, while maintaining FP like high dynamic range, deploys mostly FxP operations and thus reduces the processing cost and complexity substantially.