| 摘要 |
PROBLEM TO BE SOLVED: To provide a spread spectrum communication system based on a direct spreading system hardly causing mutual interference even when the band of the same frequency is shared. SOLUTION: At a spreading part 2, a signal from a data transmission part 1 on the side of transmission is spread by a code generated by a spreading code generating part 21. The chip rate of spread is controlled by a chip rate control part 22. On the side of reception, the input signal from the antenna is converted by a frequency converting part 5, inversely spread by an inverse spreading part 6 and demodulated by a demodulating part 7. Inverse spreading is performed by operating the inverse spreading part 6 while controlling a spreading code generating part 61 through a chip rate control part 62. When the chip rate of one system defines an L spreading rate as (k) for preventing interference, the chip rate of the other system becomes (L/k)×m (m: 1, 2, 3...). In this case, the spreading cycle of one system is inserted into one chip on the other side for one cycle. |
