摘要 |
In a communication system which conforms to the IS-99 standard, a concatenated code is used to provide for error free file transfer over the air. The concatenated code comprises Reed-Solomon coding, CRC block coding, and convolutional coding. The file is partitioned into data frames and Reed-Solomon encoding is performed on the data frames. CRC block encoding is then performed on the Reed-Solomon encoded data. The CRC encoded data is convolutionally encoded. The CRC block encoding and convolutional encoding are performed in accordance with the IS-99 standard. The additional Reed-Solomon encoding step provides improved error correction capability while maintaining compatibility with the IS-99 standard. At the receiver, Reed-Solomon decoding is performed if the number of erasures in a code word is less than or equal to (n-k) or the symbol errors in a code word is less than or equal to (n-k)/2. Otherwise, a request for retransmission is sent.
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