MULTI-CHANNEL MULTI-SYSTEM RADIO FREQUENCY UNIT OF A SATELLITE NAVIGATION RECEIVER

摘要

The invention relates to multisystem radio-frequency units of navigational satellite receivers and may be used for the simultaneous reception of any combination of navigation signals from multiple navigation systems: GLONASS, GPS, Galileo, BeiDou, IRNSS and QZSS. The unit made based on the "system-on-chip" technology comprises four identical independently configurable reception channels with a high degree of isolation from interpenetration of a signal and contaminating signals, two heterodyne frequency synthesizers having a single heterodyne signal generation mode for all four channels, a quadrature heterodyne signal driver for quadrature mixers and an automatic intermediate frequency filter band calibration system. Each reception channel comprises a quadrature mixer with image channel suppression adapted to select an upper or lower stop band, and a digital-to-analog automatic intermediate frequency gain control system. When the claimed unit operates, any reference frequency from the specified band is used for receiving the signal, as well as any conversion frequency from the specified band for quadrature mixers. The clock frequency for a correlator is obtained from the heterodyne frequency generated by any of two integrated frequency synthesizers.