Performance and Bounds of Optical Receivers with Electronic Detection and Decoding

The work investigates electronic receivers with digital signal processing (DSP) for intensitymodulated optical communication systems. The investigated DSP methods are based on probabilistic signal detection and forward error correction (FEC) coding. The Viterbi and the BCJR (Bahl-Cocke-Jelinek-Raviv) algorithm are used for probabilistic signal detection; lowdensity parity check (LDPC) codes and Reed-Solomon codes for FEC. Also, receivers with concatenated signal detection and FEC decoding, like Turbo equalizers, are investigated. Further, lower signal-to-noise ratio (SNR) bounds of error-free data communication are determined for all investigated receiver structures. In a fi1nal step, the performances of all investigated receiver structures are compared and are evaluated by use of the previously determined SNR bounds.