Bouallegue, "Cramer-Rao lower bound for NDA SNR estimation from linear modulation schemes over flat Rayleigh fading
Yang, "LDPC-coded Modulation for Transmission over AWGN and Flat Rayleigh Fading Channels," Master's thesis, Faculte' Des Sciences Et De Genie' Universite' Laval Que'bec, 2010.
1 Simulations parameters and their values Parameters Values Digital Modulation QPSK, 8QAM, 16QAM, 64QAM, 265QAM Distance between Source 1Km and Destination, d Number of Relay Nodes, N 1, 4, 8 Channels AWGN, flat Rayleigh fading LDPC Codes WiMAX LDPC codes LDPC Code Rate, r 1/2, 2/3, 3/4, 5/6 Codeword Length, n 2304 bit Encoding Richardson-Urbanke algorithm Decoding Logarithmic BP algorithm Maximum number of iterations 30 Table.
To overcome these problems, we devise a new LLR approximation using Padee approximation 22] on the uncorrelated flat Rayleigh fading channels with unknown CSI for BPSK and 8-PAM.
Figure 5 shows bit error rate (BER) of ([lambda](x), [rho](x)) = ([x.sup.2], [x.sup.3]) LDPC codes with N = 15000 for the uncorrelated flat Rayleigh fading channel with 8-PAM.
In this paper, we apply the Padee approximation, which is a generalization of the Taylor approximation, to the LLR function on the uncorrelated flat Rayleigh fading channels with unknown CSI.
Since the jointly statistical analysis of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] for j = 1,2, ..., [N.sub.k] may be difficult in flat Rayleigh fading
channels that are changing between time slots, we assume that [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] are independent.
where [x.sub.m] is the m-th user's data, [R.sub.mn] is the received signal from the m-th user to the n-th user, [g.sub.mn] is the flat Rayleigh fading channel coefficient between the m-th user and the n-th user, and [z.sub.m] is AWGN with zero mean and [N.sub.0] variance.
The flat Rayleigh fading channels are also assumed.