Radio frequency receiver of BeiDou radio determination satellite service (RDSS) satellite navigation system

Abstract

The invention relates to a radio frequency receiver of a BeiDou radio determination satellite service (RDSS) satellite navigation system. According to the receiver, a twice frequency conversion structure is adopted; a radio frequency signal is converted into a first intermediate frequency signal by using down conversion through a radio frequency front-end circuit; after being filtered, the frequency of the first intermediate frequency signal is converted into a clock sampling frequency by using the down conversion; on one hand, after being added with a driver, the clock sampling frequency serves as a sampling operating frequency of post-circuits; and on the other hand, the clock sampling frequency is subjected to divide-by-4 frequency dividing, an intermediate frequency output signal required by a system is acquired, and the intermediate frequency output signal enters the post-circuits. The receiver comprises a low noise amplifier, two stages of mixer, filters, a variable gain amplifier, an automatic gain control circuit, a divide-by-4 frequency divider, a drive circuit, an analog to digital converter, a fractional frequency division phase locked loop of an internal radio frequency voltage control oscillator and a divide-by-3 frequency divider circuit, wherein the internal radio frequency voltage control oscillator generates two stages of local oscillator signals.

Description

technical field [0001] The invention relates to a radio frequency receiving circuit, in particular to a chip circuit design of a Beidou RDSS satellite navigation system radio frequency receiver. Background technique [0002] With the operation of my country's Beidou satellite navigation experimental system, the development of the global satellite navigation system is gradually forming a pattern of four parties, namely the GPS of the United States, the GLONASS of Russia, the GALILEO system of the European Union and the Beidou system of China. The Beidou satellite navigation system is a global satellite navigation system independently built by China, operated independently, and compatible with other satellite navigation systems in the world. Its creation and development have completely broken the monopoly of Western countries in global satellite navigation technology. It has great and far-reaching significance in economic, political, and military aspects. The Beidou system ca...

AI Technical Summary

Problems solved by technology

All these factors are not conducive to the independent development and popularization of the Beidou system

[0006] Most of the current Beidou RDSS receivers use a frequency conversion structure, resulting in poor image suppression performance. Even if some receivers use a double frequency conversion structure, they are composed of two frequency synthesizers, that is, two voltage-controlled oscillators with different frequency bands. The loop part of the phase-locked loop and the separate phase-locked loop provide two-level local oscillator signals, and the module that provides the clock function for the subsequent circuit also needs to be generated by another phase-locked loop circuit in the receiver chip, which leads to complex systems and low power consumption. High, the on-chip interference of the local oscillator signal is serious

More importantly, the frequency synthesizer that provides the local oscillator signal adopts an integer frequency-division phase-locked loop structure, which will reduce the phase noise of the local oscillator signal under the application of special frequency points and high frequency division ratios, thereby reducing the receiver Sensitivity and anti-interference performance

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