| 摘要 |
An improved navigation satellite receiver with a digital channel processor including a triple carrier mixer with an early carrier mixer, a punctual carrier mixer and a late carrier mixer all connected to receive I and Q sample outputs from an IF downconverter. A triple carrier numeric controlled oscillator (NCO) includes an early carrier NCO, a punctual carrier NCO and a late carrier NCO for synthesizing three independent local carrier frequency outputs that are separated in phase from one another. A triple code mixer connects to the triple carrier mixer and comprises an inphase early-carrier early-code mixer, an inphase punctual-carrier punctual-code mixer, an inphase late-carrier late-code mixer, a quadrature early-carrier early-code mixer, a quadrature punctual-carrier punctual-code mixer, and a quadrature late-carrier late-code mixer with corresponding outputs for each mixer. A set of six correlators connected to the triple code mixer provide information to the microcomputer for the control of the triple carrier NCO in three independent carrier tracking loops that use three corresponding time-delayed points on the overall autocorrelation function and form a corrected carrier phase measurement substantially independent of multipath interference.
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