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Full-Text Articles in Engineering
On Block-Coded Modulation Using Unequal Error Protection Codes Over Rayleigh-Fading Channels, Robert H. Morelos-Zaragoza, Tadao Kasami, Shu Lin, Hideki Imai
On Block-Coded Modulation Using Unequal Error Protection Codes Over Rayleigh-Fading Channels, Robert H. Morelos-Zaragoza, Tadao Kasami, Shu Lin, Hideki Imai
Faculty Publications
This paper considers block-coded 8-phase-shift-keying (PSK) modulations for the unequal error protection (UEP) of information transmitted over Rayleigh-fading channels. Both conventional linear block codes and linear UEP (LUEP) codes are combined with a naturally labeled 8-PSK signal set, using the multilevel construction of Imai and Hirakawa (1977). Computer simulation results are presented showing that, over Rayleigh-fading channels, it is possible to improve the coding gain for the most significant bits with the use of binary LUEP codes as constituent codes, in comparison with using conventional binary linear codes alone.
Coded Modulation For Satellite Broadcasting, Robert H. Morelos-Zaragoza, Oscar Y. Takeshita, Hideki Imai, Marc P. C. Fossorier, Shu Lin
Coded Modulation For Satellite Broadcasting, Robert H. Morelos-Zaragoza, Oscar Y. Takeshita, Hideki Imai, Marc P. C. Fossorier, Shu Lin
Faculty Publications
In this paper, three-level block coded 8-PSK modulations, suitable for satellite broadcasting of digital TV signals, are presented. A design principle to achieve unequal error protection is introduced. The coding scheme is designed in such a way that the information bits carrying the basic definition TV signal have a lower error rate than the high definition information bits. The large error coefficients, formally associated with standard mapping by set partitioning, are reduced by considering a nonstandard partition of an 8-PSK signal set. The bits-to-signal mapping induced by this partition allows the use of suboptimal low-complexity soft-decision decoding of binary block …
On Primitive Bch Codes With Unequal Error Protection Capabilities, Robert H. Morelos-Zaragoza, Shu Lin
On Primitive Bch Codes With Unequal Error Protection Capabilities, Robert H. Morelos-Zaragoza, Shu Lin
Faculty Publications
Presents a class of binary primitive BCH codes that have unequal-error-protection (UEP) capabilities. The authors use a previous result on the span of their minimum weight vectors to show that binary primitive BCH codes, containing second-order punctured Reed-Muller (RM) codes of the same minimum distance, are binary-cyclic UEP codes. The values of the error correction levels for this class of binary LUEP codes are estimated.
Multilevel Block Coded 8-Psk Modulations Using Unequal Error Protection Codes For The Rayleigh Fading Channel, Robert H. Morelos-Zaragoza, Tadeo Kamasi, Shu Lin
Multilevel Block Coded 8-Psk Modulations Using Unequal Error Protection Codes For The Rayleigh Fading Channel, Robert H. Morelos-Zaragoza, Tadeo Kamasi, Shu Lin
Faculty Publications
This paper introduces new block coded 8-PSK modulations with unequal error protection (UEP) capabilities for Rayleigh fading channels. The design of efficient block coded modulations (BCM) over 8-PSK signal sets, for the specific purpose of UEP, over Rayleigh fading channels is considered. UEP is desirable in communications systems where part of the source information is more important, or error sensitive, such as the transmission of coded speech and data broadcasting. The proposed block modulation codes are based on the multilevel construction of Imai and Hirakawa (1977). It is shown that the use of binary linear UEP (LUEP) codes as component …
Qpsk Block-Modulation Codes For Unequal Error Protection, Robert H. Morelos-Zaragoza, Shu Lin
Qpsk Block-Modulation Codes For Unequal Error Protection, Robert H. Morelos-Zaragoza, Shu Lin
Faculty Publications
Unequal error protection (UEP) codes find applications in broadcast channels, as well as in other digital communication systems, where messages have different degrees of importance. Binary linear UEP (LUEP) codes combined with a Gray mapped QPSK signal set are used to obtain new efficient QPSK block-modulation codes for unequal error protection. Several examples of QPSK modulation codes that have the same minimum squared Euclidean distance as the best QPSK modulation codes, of the same rate and length, are given. In the new constructions of QPSK block-modulation codes, even-length binary LUEP codes are used. Good even-length binary LUEP codes are obtained …
On A Class Of Optimal Nonbinary Linear Unequal-Error-Protection Codes For Two Sets Of Messages, Robert H. Morelos-Zaragoza, Shu Lin
On A Class Of Optimal Nonbinary Linear Unequal-Error-Protection Codes For Two Sets Of Messages, Robert H. Morelos-Zaragoza, Shu Lin
Faculty Publications
Several authors have addressed the problem of designing good linear unequal error protection (LUEP) codes. However, very little is known about good nonbinary LUEP codes. We present a class of optimal nonbinary LUEP codes for two different sets of messages. By combining t-error-correcting ReedSolomon (RS) codes and shortened nonbinary Hamming codes, we obtain nonbinary LUEP codes that protect one set of messages against any t or fewer symbol errors and the remaining set of messages against any single symbol error. For t ≥ 2, we show that these codes are optimal in the sense of achieving the Hamming lower bound …
Unequal Error Protection Qpsk Modulation Codes, Robert H. Morelos-Zaragoza, Shu Lin
Unequal Error Protection Qpsk Modulation Codes, Robert H. Morelos-Zaragoza, Shu Lin
Faculty Publications
The authors use binary linear UEP (LUEP) codes, in combination with a QPSK signal set and Gray mapping, to obtain new efficient block QPSK modulation codes with unequal minimum squared Euclidean distances. They give several examples of codes that have the same minimum squared Euclidean distance as the best QPSK modulation codes of the same rate and length. A new suboptimal two-stage soft-decision decoding is applied to LUEP QPSK modulation codes.