Design and implementation of a high-sensitivity receiver channel for the BeiDou RDSS

Area of Science:

• Satellite communication systems
• Radio frequency engineering
• Signal processing

Background:

• BeiDou Radio Determination Satellite Service (RDSS) applications require enhanced receiver sensitivity and long-term operational stability.
• Existing user terminals face challenges in reliably receiving weak signals over extended periods.

Purpose of the Study:

• To develop a novel RDSS-oriented receiver design that significantly improves reception sensitivity and long-term operational stability.
• To address the stringent requirements for BeiDou RDSS short-message user terminals.

Main Methods:

• Optimized a two-stage cascaded low-noise amplifier (LNA) front end for enhanced sensitivity.
• Implemented a superheterodyne down-conversion chain and noncoherent signal acquisition for frequency offset tolerance.
• Developed a cost-efficient local oscillator (LO) aging compensation approach using an improved resistor divider tuning network and embedded software.

Main Results:

• Achieved a total gain of 28.19 dB and a noise figure (NF) of 1.87 dB.
• Satisfied sensitivity requirements with a bit error rate (BER) of [Formula: see text] at -127.6 dBm and near-threshold demodulation at -128.1 dBm.
• Demonstrated a 99.31% message success rate on an end-to-end testing platform, exceeding the 95% requirement.

Conclusions:

• The proposed high-sensitivity receiver design offers competitive weak-signal reception capabilities.
• The LO aging compensation approach effectively mitigates frequency drift, ensuring reliable reception over years.
• The solution provides practical engineering value, supporting the widespread deployment of BeiDou RDSS short-message services.