Title :
Performance analysis of CDMA systems by using biorthogonal codes
Author :
Seung-Hee, Hong ; Jong-Seon, No
Author_Institution :
Daeyoung Electron. Ind. Co. Ltd., Kyoungi-Di, South Korea
Abstract :
A new CDMA system is proposed, which is composed of very low rate convolutional codes and biorthogonal codes. Convolutional encoders with rate 1/64 and constraint length 7 and 128 rows×64 chips biorthogonal codes generated from Walsh codes with 64 rows×64 chips are used for encoding and spreading. A Viterbi decoder is used for demodulating the newly designed CDMA system. The performance of proposed CDMA system using biorthogonal codes is better than that of the CDMA system using FEC and orthogonal modulation, and from the hardware complexity point of view, the amount of computation for implementing the proposed CDMA system is increased only a little
Keywords :
Viterbi decoding; Walsh functions; code division multiple access; convolutional codes; land mobile radio; modulation coding; pseudonoise codes; quadrature phase shift keying; spread spectrum communication; CDMA systems; Viterbi decoder; Walsh codes; biorthogonal codes; constraint length; convolutional encoders; demodulation; hardware complexity; performance analysis; spreading; very low rate convolutional codes; Convolution; Convolutional codes; Decoding; Encoding; Hardware; Mobile communication; Modulation coding; Multiaccess communication; Performance analysis; Viterbi algorithm;
Conference_Titel :
Vehicular Technology Conference, 1995 IEEE 45th
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-2742-X
DOI :
10.1109/VETEC.1995.504957
