Abstract: A multiple phase shift keying (MPSK) spread spectrum communications receiver uses weighted correlation techniques for carrier recovery and tracking. The receiver includes three subsystems: a synchronization system, a carrier tracking system, and a data demodulation system. To demodulate the received signal, the receiver requires a carrier frequency that matches the frequency of an associated transmitter as well as the sampling (or chip) and symbol clocks that are synchronized with those of the transmitter. In the disclosed receiver, the carrier tracking subsystem continually tracks the carrier frequency of the received signal using a tracking scheme that uses weighted correlation techniques. The weighted correlation technique combines signals from two correlator modules, an R-correlator module and a W-correlator module, to generate the correlation output. The R-correlator is similar to conventional correlators. The W-correlator, however, is unlike conventional correlators.

Abstract: This invention relates to a broad band spread spectrum communications receiver with carrier recovery and tracking based on multiple phase shift keying (MPSK) techniques. The receiver comprises three subsystems: the synchronization system, the carrier tracking system and the data demodulation system. To demodulate the received signal, the receiver requires a carrier frequency that matches that of the transmitter as well as the chip and symbol clocks that are synchronized with those of the transmitter. In the disclosed system the carrier tracking subsystem continually tracks the carrier frequency of the received signal using a tracking scheme which is based on correlation techniques. The synchronization subsystem synchronizes the symbol clock and chip clock. These three subsystems interact with each other and result in an improved bit error rate (BER) performance.

Abstract: A multiple phase shift keying (MPSK) spread spectrum communications receiver uses weighted correlation techniques for carrier recovery and tracking. The receiver includes three subsystems: a synchronization system, a carrier tracking system, and a data demodulation system. To demodulate the received signal, the receiver requires a carrier frequency that matches the frequency of an associated transmitter as well as the sampling (or chip) and symbol clocks that are synchronized with those of the transmitter. In the disclosed receiver, the carrier tracking subsystem continually tracks the carrier frequency of the received signal using a tracking scheme that uses weighted correlation techniques. The weighted correlation technique combines signals from two correlator modules, an R-correlator module and a W-correlator module, to generate the correlation output. The R-correlator is similar to conventional correlators. The W-correlator, however, is unlike conventional correlators.