Title :
Performance analysis of hierarchical coded modulation systems
Author :
Lim, J.-H. ; Gelfand, S.B.
Author_Institution :
Sch. of Electr. & Comput. Eng., Purdue Univ., West Lafayette, IN, USA
Abstract :
In this paper, analytical performance bounds are presented for a hierarchical coded modulation system of the type which has been proposed for backward compatibility and/or variable error rate protection. This system uses two convolutional encoders (and two Viterbi (1989) decoders) with a hierarchical 16-QAM constellation, and is compatible with an existing QPSK based coded system. In the AWGN channel, we derive upper bounds for four different schemes (two decoding schemes, multi-stage decoding (MSD) and independent decoding(ID), and two labeling schemes, Gray labeling (GL) and non-Gray labeling (NGL)). We show that the performance of the simple GL with ID scheme is nearly optimum in the AWGN channel. Then we analyze the GL with ID scheme in the Rayleigh fading channel. Simulation results are given for comparison with the bounds
Keywords :
AWGN channels; Rayleigh channels; Viterbi decoding; convolutional codes; modulation coding; quadrature amplitude modulation; quadrature phase shift keying; AWGN channel; Gray labeling; QPSK based coded system; Rayleigh fading channel; Viterbi decoders; analytical performance bounds; backward compatibility; convolutional encoders; hierarchical 16-QAM constellation; hierarchical coded modulation systems; independent decoding; multi-stage decoding; nonGray labeling; performance analysis; simulation results; upper bounds; variable error rate protection; AWGN channels; Convolutional codes; Decoding; Error analysis; Labeling; Modulation coding; Performance analysis; Protection; Quadrature phase shift keying; Viterbi algorithm;
Conference_Titel :
Global Telecommunications Conference, 2000. GLOBECOM '00. IEEE
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-6451-1
DOI :
10.1109/GLOCOM.2000.891908
