Title :
Structure, optimization, and realization of FFSK trellis codes
Author :
Moreno, Fidel Morales ; Pasupathy, Subbarayan
Author_Institution :
Dept. of Electr. Eng., New Jersey Inst. of Technol., Newark, NJ, USA
fDate :
7/1/1988 12:00:00 AM
Abstract :
The structure of combinations of (l,k) binary trellis encoders and fast frequency-shift keying (FFSK) modulation is studied. A novel method for the optimization of these combinations is proposed. It is concluded that, regardless of the particular realization, the best combinations can always be obtained by using a so-called matched convolutional code. Optimum FFSK codes of rates 1/2 and 2/3 for up to 64 and 32 states, respectively, are reported. It is shown that the best matched encoders for FFSK modulation are also matched and best for any FFSK-type scheme, where the pulse shape is required to satisfy Nyquist´s third criterion
Keywords :
codes; encoding; frequency shift keying; optimisation; FFSK modulation; Nyquist´s third criterion; binary trellis encoders; fast frequency-shift keying; matched convolutional code; optimization; trellis codes; Convolution; Convolutional codes; Decoding; Euclidean distance; Frequency modulation; Frequency shift keying; Mexico Council; Modulation coding; Optimization methods; Viterbi algorithm;
Journal_Title :
Information Theory, IEEE Transactions on
