Multi-phase vector synthesis demodulation method and apparatus

A demodulation apparatus at a receiver of communications systems that transmit one or more carrier modulated signals, the demodulation apparatus comprising:

• one or more local oscillators for generating an N number of phase-shifted carrier signals, wherein each phase of the N number of phase-shifted carrier signals is successively and equally shifted by N/360°, where N is an odd number greater than or equal to 3;
• an N number of mixers for mixing a received signal with the N number of phase-shifted carrier signals and producing N-phase mixed signals;
• an N number of band-pass filters for band-pass filtering the N-phase mixed signals and obtaining N-phase demodulated baseband signals by filtering out carrier signal components;
• and
• an N-phase zero-force synthesizer for synthesizing in-phase (I) and quadrature-phase (Q) signals from the N-phase demodulated baseband signals, wherein synthesis coefficients and gain are pre-determined.

A computer program for demodulation of a carrier modulated signal in a communication system, the computer program stored in a non-transitory computer-readable storage medium and configured to execute one or more microprocessor software modules to:

• generate an N number of phase-shifted carrier signals;
• generate N-phase mixed signals by mixing a received signal with the N number of phase-shifted carrier signals;
• generate an N-phase demodulated baseband signals by removing a carrier or intermediate frequency from the N-phase mixed signals;
• and
• synthesize I and Q signals from the N-phase demodulated baseband signals by a zero-force synthesis.