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Item This letter presents techniques for improving the distribution of the number of stack entries, for stack sequential decoding over hard quantized channel, with emphasis on high rate codes. It is shown that, for a class of high rate b/(b+1) codes, a table-based true high rate approach can be easily implemented for obtaining decoding advantage over the punctured approach. Modified algorithms, which significantly improve the distribution of the number of stack entries and decoding time, are proposed for rate 1/N codes and high rate b/(b+1) codes.(IEEE, On low complexity stack decoding of convolutional codes) D'Souza, J.; Maskara, S.L.1999Item Performance of Spatially Coupled LDPC Codes over the Underwater Wireless Optical Channel with Strong Turbulence and Pointing Errors(Institute of Electrical and Electronics Engineers Inc., 2024) Padala, S.K.; D'Souza, J.The major problems in an underwater wireless optical communication (UWOC) link are turbulence induced fading and pointing errors. In this paper, we have investigated the bit error rate (BER) performance of spatially coupled low-density parity-check (SC-LDPC) coded horizontal UWOC link over a strong turbulent channel model with pointing errors. The performance of this link for different channel and code parameters has been studied using simulations. It has been observed that a rate 1/2 ARJA protograph based SC-LDPC code with graph lifting factor of 256 gives a coding gain of 47 dB at a BER of 10^-4 for strong turbulence channel model with pointing errors. An analytical BER expression for an uncoded UWOC link under strong turbulence with pointing errors for the On-Off Keying modulation technique has been derived. A multidimensional protograph based extrinsic information transfer algorithm has been developed to obtain the decoding thresholds for different channel parameters and code rates. We have also studied the SC-LDPC coded vertical UWOC link performance for some specific strong turbulence channel parameters with pointing errors and observed that as the link length increases from 20 m to 40 m , the performance gap between the hypothetical and cascaded channel models increases from 1.1 dB to 5.5 dB. © 2013 IEEE.