Communication system, transmitter and receiver

摘要

Differences between adjacent two bits of connection control data are derived in sequence. The derived differences are logically combined with a pilot signal and simultaneously with user data. The logically combined signals are spread to spreading bands and added to each other. The added signal is used as a modulating signal and transmitted through phase shift keying (PSK). Thereafter, a PSK carrier is demodulated to derive the modulating signal. The modulating signal is despread to derive a user signal. The user signal includes the user data and the foregoing differences. The modulating signal is further despread to derive the pilot signal with the foregoing differences included. The pilot signal with the foregoing differences is subjected to a conjugate conversion and then multiplied by the user signal so that the foregoing differences are removed from the user signal to obtain the user data. The connection control data is reconstructed from the foregoing differences included in the pilot signal.