Title :
Rate l/(l+1) convolutional encoders over rings with maximal free branch distance
Author :
Gu, Wei-Hsin ; Lu, Chung-Chin
Author_Institution :
Dept. of Electr. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
When we consider convolutional coded CPFSK over fading channels, the primary design criterion (for high SNR) is to maximize the effective code length (ECL), where ECL is the minimal possible Hamming distance between any two distinct symbol sequences. We define the free branch distance (dfree) as the minimal possible branch distance between any two (unlabeled) parallel paths in the code trellis. We show that dfree achieving the maximum value is a necessary condition for maximizing ECL
Keywords :
continuous phase modulation; convolutional codes; fading channels; frequency shift keying; Hamming distance; code rate; code trellis; convolutional coded CPFSK; convolutional encoders; effective code length; fading channels; finite field; high SNR; maximal free branch distance; necessary condition; rings; symbol sequences; Computer aided software engineering; Contracts; Convolutional codes; Councils; Fading; Galois fields; Hamming distance; Intersymbol interference; Modules (abstract algebra); Upper bound;
Conference_Titel :
Information Theory, 2001. Proceedings. 2001 IEEE International Symposium on
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-7123-2
DOI :
10.1109/ISIT.2001.936029
