A new SISO algorithm with application to turbo equalization

Marcin Sikora; Daniel J. Costello Jr

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A new SISO algorithm with application to turbo equalization

Marcin Sikora·Daniel J. Costello Jr

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Abstract

In this paper we propose a new soft-input soft-output equalization algorithm, offering very good performance/complexity tradeoffs. It follows the structure of the BCJR algorithm, but dynamically constructs a simplified trellis during the forward recursion. In each trellis section, only the M states with the strongest forward metric are preserved, similar to the M-BCJR algorithm. Unlike the M-BCJR, however, the remaining states are not deleted, but rather merged into the surviving states. The new algorithm compares favorably with the reduced-state BCJR algorithm, offering better performance and more flexibility, particularly for systems with higher order modulations.

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Marcin Sikora, Daniel J. Costello Jr. 2005-04-06. A new SISO algorithm with application to turbo equalization. https://arxiv.org/abs/cs/0504017

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