Frequency spectral line tracking receiver

摘要

An improved navigation satellite receiver for tracking individual spread-spectrum frequency spectral lines with a microwave receiver antenna to receive signals from orbiting navigation satellites, a downconverter to produce in-phase and quadrature (I and Q) signals from the received satellite signals, and a digital processing system for frequency and phase locking numeric controlled oscillators (NCO) to the carrier and code of the satellite signals. The improvement comprises at least one spectral line tracker connected to receive the (I and Q) signals and including a spectral line numeric controlled oscillator (NCO) connected to a spectral line mixer that drives a spectral line code correlator. The spectral line NCO is frequency-aided to frequency lock on a spectral line from a value obtained from the carrier NCO.