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Exploiting UEP in QAMbased BICM: Interleaver and code design
 IEEE Trans. Commun
, 2010
"... In this paper we formally analyze the interleaver and code design for QAMbased BICM transmissions using the binary reflected Gray code. We develop analytical bounds on the bit error rate and we use them to predict the performance of BICM when unequal error protection (UEP) is introduced by the cons ..."
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Cited by 7 (4 self)
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In this paper we formally analyze the interleaver and code design for QAMbased BICM transmissions using the binary reflected Gray code. We develop analytical bounds on the bit error rate and we use them to predict the performance of BICM when unequal error protection (UEP) is introduced by the constellation labeling. Based on these bounds the optimum design of interleaver and code is found, and numerical results for representative configurations are presented. When the new design is used, the improvements may reach 2 dB, and they are obtained without complexity increase. We also introduce the concept of generalized optimum distance spectrum convolutional codes, which are the optimum codes for this scenario.
On the distribution of Lvalues in graymapped M 2 QAM signals: Exact expressions and simple approximations
 in IEEE Global Commun. Conf
, 2007
"... Abstract — In this paper we develop formulas for the probability density function (PDF) of the reliability metrics in bitinterleaved coded modulation (BICM) for arbitrary M 2ary quadrature amplitude modulation (M 2QAM) with Gray mapping. The advantage of this approach over an entirely general one ..."
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Cited by 5 (3 self)
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Abstract — In this paper we develop formulas for the probability density function (PDF) of the reliability metrics in bitinterleaved coded modulation (BICM) for arbitrary M 2ary quadrature amplitude modulation (M 2QAM) with Gray mapping. The advantage of this approach over an entirely general one proposed previously, is that the resulting formulas are obtained without resorting to any algorithmic steps. We also propose Gaussian mixture approximations that are analytically tractable, and we analyze their accuracy when evaluating uncoded bit error rate (BER) and BICM capacity.
Constellation labeling maps for low error floors
 in Proc. IEEE Military Commun. Conf. (MILCOM
, 2007
"... Abstract—A constellation labeling map is the assignment of a bit pattern to each symbol in a signalset constellation. In a system with iterative decoding and demodulation, the error floor of the bit error rate is highly dependent on the labeling map. A simple class of labeling maps that significant ..."
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Cited by 3 (1 self)
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Abstract—A constellation labeling map is the assignment of a bit pattern to each symbol in a signalset constellation. In a system with iterative decoding and demodulation, the error floor of the bit error rate is highly dependent on the labeling map. A simple class of labeling maps that significantly lower the error floors is presented. Examples show the applications of the proposed mapping to multiple phaseshift keying (MPSK), quadrature amplitude modulation (QAM), and continuousphase frequencyshift keying (CPFSK). Simulation results indicate that the proposed labeling maps are comparable to or better than other labeling maps in providing a low error floor. A major advantage of the proposed labeling maps is that they are easily generated even when the alphabet size is large. Index Terms—Constellation, labeling map, error floor, iterative decoding, bitinterleaved coded modulation. I.
Distribution of Lvalues in Graymapped M 2 QAM: Closedform approximations and applications
 IEEE Trans. Commun
, 2009
"... Abstract — In this paper we develop closed form approximations for the probability density function (PDF) of the reliability metrics (Lvalues) in bitinterleaved coded modulation (BICM). The expressions are valid for M 2ary quadrature amplitude modulations (M 2QAM) with Gray mapping when the metr ..."
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Abstract — In this paper we develop closed form approximations for the probability density function (PDF) of the reliability metrics (Lvalues) in bitinterleaved coded modulation (BICM). The expressions are valid for M 2ary quadrature amplitude modulations (M 2QAM) with Gray mapping when the metrics are calculated using the socalled maxlog approximation. Based on the developed expressions, we also propose two simple Gaussian mixture approximations that are analytically tractable. We apply our developments to efficiently calculate the BICM capacity, and to develop bounds on the coded biterror rate when a convolutional code is used. The coded performance of a hybrid automatic repeat request (HARQ) based on constellation rearrangement is also evaluated.
Combined Packet Retransmission Diversity and Power Adjustment Scheme for High Speed Wireless Networks
"... improve the bearer capacity of the mobile network and make the dream of multimedia communications, anytime and anywhere, come true. One of the central features of HSDPA concept is advanced physical layer retransmission scheduling employing soft combining gain, incremental redundancy, and low retrans ..."
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improve the bearer capacity of the mobile network and make the dream of multimedia communications, anytime and anywhere, come true. One of the central features of HSDPA concept is advanced physical layer retransmission scheduling employing soft combining gain, incremental redundancy, and low retransmission delays. This paper studies symbol mapping diversity in combination with power adjustment for HSDPA. If retransmission are requested, the bittosymbol mapping and transmission power is changed in every retransmission. Compared to the conventional HARQ schemes, our proposed scheme increases the throughput and decreases the average number of retransmissions significantly and reduce the power consumption in HSDPA. Index Terms—Constellation rearrangement, Diversity, LLR, Power adjustment, MQAM, BER
constellation rearrangement ‡
"... Evaluation of bit error rate for packet combining with ..."
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BER Evaluation of BICMID via
"... Abstract—In this paper, we evaluate the bit error rate (BER) of bitinterleaved coded modulation (BICM) receivers that operate with aprioriinformation obtained from the decoder during the socalled turbo iterations. We use Bonferronitype lower and upper bounds to tightly estimate the BER performance ..."
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Abstract—In this paper, we evaluate the bit error rate (BER) of bitinterleaved coded modulation (BICM) receivers that operate with aprioriinformation obtained from the decoder during the socalled turbo iterations. We use Bonferronitype lower and upper bounds to tightly estimate the BER performance in the range of signaltonoise ratio (SNR) of interest. The results are shown to be useful for the convergence analysis of the iterative demapping via the socalled extrinsic information transfer (EXIT) charts and for the evaluation of the coded performance of BICM with iterative demapping (BICMID). Index Terms—BICM with iterative demapping (BICMID), bitinterleaved coded modulation (BICM), Bonferroni bounds, iterative demapping, turbo decoding, turbo demapping. I.