한국정보통신학회논문지 (Journal of the Korea Institute of Information and Communication Engineering)

  • 제9권6호
  • /
  • Pages.1195-1201
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  • 2005
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  • 2234-4772(pISSN)
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  • 2288-4165(eISSN)
한국정보통신학회 (The Korea Institute of Information and Commucation Engineering)
권호 표지

무선통신 적용을 위한 단일 DSP칩상의 음성/채널 부호화기 실시간 구현

Real-time Implementation of Speech and Channel Coder on a DSP Chip for Radio Communication System

  • 김재원 (경주대학교 컴퓨터멀티미디어공학부) ;
  • 손동철 (천안대학교 정보통신공학부)
  • 발행 : 2005.10.01
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⟨ 이전 논문 다음 논문 ⟩

초록

본 논문에서는 무선통신 시스템 적용을 위한 G.729 음성부호화기와 길쌈부호화기(R=1/2, K=9) 비터비 복호기를 하나의 고정 소수점 DSP칩을 이용하여 실시간 구현하였다. 프로그램 구현은 고정 소수점 C 프로그램을 연산결과의 기준으로 활용하였으며, 복잡도의 최적화를 위하여 어셈블 언어로 설계하였다. 최적화 과정을 통하여 구현한 결과는 연산량 측면에서 음성부호화기 24MIPS, 채널부호화기 9MIPS, 프로그램 크기 측면에서 음성 24K words, 채널 4K words가 소요되었으며, 연산의 검증은 테스트 벡터를 이용하여 Bit exact 방법에 의하여 검증하였다. 본 논문의 결과는 기존의 음성/채널 부호화기의 개별적인 칩을 이용한 구현 방법에 비하여 구현의 용이성 및 구현 비용 측면에서 성능 개선이 가능할 것으로 판단된다.

This paper deals with procedures and results for teal time implementation of G.729 speech coder and channel coder including convolution codec, viterbi decoder, and interleaver using a fixed point DSP chip for radio communication systems. We described the method for real-time implementation based on integer simulation results and explained the implemented results by quality performance and required complexity for real-time operation. The required complexity was 24MIPS and 9MIPS in computational load, and 12K words and 4K words in execution code length for speech and channel. The functional evaluation was performed into two steps. The one was bit exact comparison with a fixed point C code, the other was executed by actual speech samples and error test vectors. Unlik other results such as individual implementation, We implemented speech and channel coders on a DSP chip with 160MIPS computation capability and 64 K words memory on chip. This results outweigh the conventional methods in the point of system complexity and implementation cost for radio communication system.

키워드

참고문헌

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