Title :
Coded nonuniform phase/frequency modulation
Author :
Chalid, Aminuddin ; Sasase, Iwao ; Yashima, Hiroyuki ; Mori, Shinsaku
Author_Institution :
Dept. of Electr. Eng., Keio Univ., Yokohama, Japan
Abstract :
Coded nonuniform phase/frequency modulation is proposed to achieve a performance gain over uniformly spaced signal-constellation-coded phase/frequency modulation. In particular, the joint design of m/(m+1) systematic convolutional encoders and nonuniform 2FSK/2/sup m/PSK modulation signals are considered. The minimum free Euclidean distance of the trellis is calculated for several classes of codes, and the asymptotic performance gains due to coding and nonuniformity are evaluated. Numerical results on bit error probability are also presented for some codes to demonstrate the additional savings in required energy bit to noise ratio. It is shown that by designing the signal constellations to be nonuniform, performance gain can be obtained over the conventional coded uniform phase/frequency modulation in many instances.<>
Keywords :
encoding; error statistics; frequency modulation; phase modulation; asymptotic performance gains; bit error probability; coded nonuniform modulation; coding; frequency modulation; minimum free Euclidean distance; nonuniformity; performance gain; phase modulation; systematic convolutional encoders; uniformly spaced signal constellation coded modulation; Constellation diagram; Convolution; Convolutional codes; Error probability; Euclidean distance; Frequency modulation; Performance gain; Phase shift keying; Signal design; Signal to noise ratio;
Conference_Titel :
Communications, 1988. ICC '88. Digital Technology - Spanning the Universe. Conference Record., IEEE International Conference on
Conference_Location :
Philadelphia, PA, USA
DOI :
10.1109/ICC.1988.13654
