Research And Design Of RF Front-end Circuit For The Beidou Satellite Navigation System

The Beidou satellite navigation system is independently developed by China, and the purpose is to consolidate Chinese military strength in an increasingly grim world. The Beidou ratio frequency receiver (RF receiver) chip is the core of the entire ground-side equipment of the Beidou satellite navigation system, therefore the RF receiver chip's research and design work has important practical significance. Low-noise amplifier and mixer are important component modules of the RF receiver chip, and they should have both the low noise figure and high linearity. This dissertation completes the following works:First, the RF front-end circuit used in the the Beidou first-generation satellite navigation system is designed, and it mainly includes the low-noise amplifier (LNA) and the mixer circuit modules. During the RF front-end circuit's design, a more stable single-ended to differential low-noise amplifier circuit is put forward by introducing a negative feedback.Second, the RF front-end circuit applied to the Beidou second-generation satellite navigation system is designed, and it mainly includes the low-noise amplifier and the mixer circuit blocks. During the RF front-end circuit's design, a single switch to dual circuit low-noise amplifier with higher balance is put forward by introducing a phase compensation. The mixer's design uses the current injection technology, and at the same time, improves the swing of the LO signal by adding buffer to the local oscillator port, thereby enhances the gain and reduces the noise.Third, an image rejection solution for the receiver in the Beidou second-generation satellite navigation system is designed on the basis of the design of the low noise amplifier, mixer and the Hartley receiver structure. This solution is different from the traditional ones adopting polyphase filter, for it uses the RC phase shifter network to achieve the mixer's output signal's relative 90-degree phase shift.