Accession Number : ADA319761

Title :   Multiprocessor Implementation of a Real-Time Celp Algorithm.

Descriptive Note : Final rept. Apr 94-Oct 95,

Corporate Author : KANSAS UNIV CENTER FOR RESEARCH INC LAWRENCE TELECOMMUNICATIONS AND INFORMATI ON SCIENCES LAB

Personal Author(s) : Prescott, Glenn ; Chakravarthula, Hari N. ; Sivaprakasam, Sinivas ; Johnson, Timouthy

PDF Url : ADA319761

Report Date : NOV 1996

Pagination or Media Count : 91

Abstract : The objective of this effort was to develop the methodology of transferring communication signal processing algorithms from a single processor (SUN Workstation) to multiple DSP processors TMS32OC4Os. The CELP (Code Excited Linear Prediction) voice compression algorithm was chosen for real time implementation of 3 processors. The algorithm operates at an output rate of 4800 bits per second with an input sampling rate of 8000 samples per second. Using efficient parallel processing algorithms (optimized to reduce the inter-processor communication time overhead) one can implement complicated communication functions such as the CELP algorithm on more than one processor and achieve real time performance. A block diagram description of the CELP algorithm has been developed using the Signal Processing Worksystem (SPW), a block oriented design tool from the Alta Group of Cadence to generate optimized code for a VMEbus based network of TM5320C40 processors. The CELP algorithm is based on the U.S. Federal Standard 1016. Data transfers between the processors is achieved by using the C40 processors' high speed communication ports and concurrent multi channel DMA transfer capability. The approach frees the CPU of burdensome interprocessor communication functions.

Descriptors :   *ALGORITHMS, *REAL TIME, *MULTIPROCESSORS, *VOICE COMMUNICATIONS, SIGNAL PROCESSING, LINEAR SYSTEMS, INPUT, OPTIMIZATION, COMPUTER COMMUNICATIONS, PREDICTIONS, TOOLS, RATES, EFFICIENCY, PARALLEL PROCESSING, CODING, MATHEMATICAL PREDICTION, COMMUNICATIONS NETWORKS, SAMPLING, COMMUNICATION AND RADIO SYSTEMS, DIAGRAMS, DATA PROCESSING TERMINALS, SPEECH COMPRESSION.

Subject Categories : Electrical and Electronic Equipment
      Computer Hardware
      Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE