@article{(Open Science Index):https://publications.waset.org/pdf/10430, title = {Optimization of Quantization in Higher Order Modulations for LDPC-Coded Systems}, author = {M.Sushanth Babu and P.Krishna and U.Venu and M.Ranjith}, country = {}, institution = {}, abstract = {In this paper, we evaluate the choice of suitable quantization characteristics for both the decoder messages and the received samples in Low Density Parity Check (LDPC) coded systems using M-QAM (Quadrature Amplitude Modulation) schemes. The analysis involves the demapper block that provides initial likelihood values for the decoder, by relating its quantization strategy of the decoder. A mapping strategy refers to the grouping of bits within a codeword, where each m-bit group is used to select a 2m-ary signal in accordance with the signal labels. Further we evaluate the system with mapping strategies like Consecutive-Bit (CB) and Bit-Reliability (BR). A new demapper version, based on approximate expressions, is also presented to yield a low complexity hardware implementation.}, journal = {International Journal of Electronics and Communication Engineering}, volume = {6}, number = {1}, year = {2012}, pages = {75 - 81}, ee = {https://publications.waset.org/pdf/10430}, url = {https://publications.waset.org/vol/61}, bibsource = {https://publications.waset.org/}, issn = {eISSN: 1307-6892}, publisher = {World Academy of Science, Engineering and Technology}, index = {Open Science Index 61, 2012}, }