| 摘要 |
PROBLEM TO BE SOLVED: To improve a peak versus average transmission output ratio by selecting a kernel cord consisting of a prescribed number of bits, generating a complementary code whose each bit corresponds to each bit of the kernel code, converting the complementary code into a complex vector and modulating a carrier. SOLUTION: An orthogonal frequency division modulation(OFDM) transmitter 100 receives a bit stream from a data bit source 25 and a coder 30 stores the stream once in an internal memory. The coder 30 selects a kernel code in, e.g. 8-bit, and a phase rotation θi independent of each bit is assigned as a prescribed conversion function and then a complementay code θi is generated. The coder 30 generates a complementary code θi by relating bits directly related to input data extracted from a memory to the phase rotation ψi for each of a prescribed number of groups. An IFFT processor 40 converts the complementary code θi into a code for a frequency area and each phase vector is generated. A transmitter 50 applies orthogonal frequency division modulation to the carrier by an analog-converted phase vector and transmits the result. A receiver 200 demodulates the signal by the reverse procedure to above. |
