Phase difference correcting demodulator for a receiver for spread spectrum communication

摘要

A data demodulator of a receiving apparatus for spread spectrum communication for removing the phase difference remaining after detection for improving reception quality. In-phase and quadrature axis receive signals are multiplied by pseudonoise codes PNI(t) and PNQ(t) and the results are averaged by averaging sections for calculating the correlation. By performing correlation processing, ρk0 cos ϑ , -ρ0 sin ϑ , ρk0 sin ϑ , and ρk0 cos ϑ are output when the amplitude of receive path signal is assumed to be ρ, the phase difference to be ϑ, and a proportional constant to be k0. These signals are multiplied by in-phase and quadrature axis receive signals and the results are added by adders, thereby removing the effect of the phase difference ϑ. The signal is used for data demodulation and data reproduction.