Patent ID: 6519295
Filing Date: 2003-02-11
Classification: H03D,H04L,H04N

Abstract:
A receiver for a baseband symbol code designed to have a spectrum reaching at least substantially to zero-frequency and transmitted by vestigial-sideband amplitude modulation of a suppressed carrier wave so as to have an asymmetrical channel response even in a narrow-frequency band including a pilot carrier signal at the frequency of said suppressed carrier wave, said receiver comprising:a local oscillator responsive to an automatic frequency and phase control signal for generating local oscillations used in detecting said vestigial-sideband amplitude modulation; a mixer for heterodyning said local oscillations with vestigial-sideband amplitude modulation of a suppressed carrier wave to generate a final intermediate-frequency signal; an analog-to-digital converter for digitizing said final intermediate-frequency signal to generate a digitized final intermediate-frequency signal; real-only digital synchrodyne means for synchrodyning said digitized final intermediate-frequency signal only with a real digital carrier; and quadrature synchrodyne means for producing said automatic frequency and phase control signal.