A Variable Length Code Transmission Technique on Multicode DS/SS Systems

• SANADA Yukitoshi

  the Faculty of Engineering, Tokyo Institute of Technology

• ARAKI Kiyomichi

  the Faculty of Engineering, Tokyo Institute of Technology

Abstract

In this paper, a new variable length code transmission technique utilizing multicode DS/SS is proposed. A common problem associated with the use of variable length codes over wireless channels is loss of synchronization due to bit inversion caused by channel noise. The loss of synchronizationproduces burst errors in the received source symbols. The proposed system assigns multiple spreading codes to a single user to transmit variable length codes. The number of the spreading codes is equal to the maximum bit length of the codewords. All the bits of the codeword are spread and transmitted at one time by utilizing the assigned multiple spreading codes. Therefore no synchronization of the codeword is required. This paper evaluates the performance of the proposed technique over an AWGN channel and a Rayleigh fading channel. Our results show that the proposed technique improves the symbol error rate (SER) performance by 2-3dB on the AWGN channel and 10-20dB on the Rayleigh fading channel as compared with a conventional transmission technique. The source-chnnel coding suitable for the proposed technique improves the performance by another 15dB on the Rayleigh fading channel. The Proposed transmission technique works even in a low Es/No region.

Journal

• IEICE Trans. Commun.

  IEICE Trans. Commun. 81 (3), 625-636, 1998-03-25

  The Institute of Electronics, Information and Communication Engineers

Keywords

• variable length code
• multicode DS
• SS
• image transmission

Details

• CRID: 1570009752558229888
• NII Article ID: 110003218116
• NII Book ID: AA10826261
• ISSN: 09168516
• Text Lang: en
• Data Source:
  • CiNii Articles