Title :
Unit memory rotationally invariant multiple trellis codes for QAM systems
Author :
AygÖlü, Ürnit ; Panayirci, Erdal
Author_Institution :
Fac. of Electr. & Electron. Eng., Istanbul Tech. Univ., Turkey
Abstract :
In this paper, new rotationally invariant two-state M-QAM trellis encoders which transmit two channel symbols per trellis branch are designed based on the MTCM approach. An ACG of 1.25 dB is obtained with respect to the classical M-QAM trellis encoders. The proposed schemes are made transparent to 90°, 180° and 270° signal element rotations by means of linear binary convolutional encoders to avoid performance degradation due to the phase ambiguities of the received signal elements. For the special case of 16-QAM, an error probability upper bound is derived analytically to evaluate the performance compared to the classical two-state 16-QAM trellis encoder
Keywords :
amplitude modulation; encoding; trellis codes; 16-QAM; ACG; M-QAM trellis encoders; QAM systems; channel symbols; error probability; linear binary convolutional encoders; performance evaluation; phase ambiguities; rotationally invariant multiple trellis codes; unit memory codes; upper bound; Amplitude modulation; Convolution; Convolutional codes; Data communication; Design engineering; Gain; Modulation coding; Performance analysis; Quadrature amplitude modulation; Upper bound;
Conference_Titel :
Singapore ICCS/ISITA '92. 'Communications on the Move'
Print_ISBN :
0-7803-0803-4
DOI :
10.1109/ICCS.1992.255158
