| 摘要 |
PROBLEM TO BE SOLVED: To reduce the bit error rate of the system by using a transmitter where a mapper connects in series with an encoder and a bit inteleaver and a receiver where a demapper connects to a bit de-interleaver and a decoder. SOLUTION: A binary random signal that is convolution-coded is fed to a random bit interleaver that interleaves a bit signal in a transmitter. An encrypted bit stream passing through the interleaver is given to a demultiplexer that conducts serial/parallel conversion, where the stream is demultiplexed into N-sets of parallel bit streams. A mapper conducts N-bit-N-bit mapping. The bit streams 1,...N after mapping receive spread processing by binary antipodal channel processing codes (code words 1,..., N) whose length is Nc chip. N-sets of the channel processing codes are usually orthogonal to each other. A receiver is provided with a demapper, which conducts repetitive demapping and decoding after de-spreading. |
