Design and implementation of a high-sensitivity receiver channel for the BeiDou RDSS
摘要
With the growing adoption of BeiDou RDSS short-message applications, increasingly stringent requirements are imposed on the reception sensitivity and long-term operational stability of user terminals. To meet these demands, we introduce an RDSS-oriented receiver design that enhances overall sensitivity by jointly optimizing a two-stage cascaded low-noise amplifier (LNA) front end, a superheterodyne down-conversion chain, and noncoherent signal acquisition in the presence of frequency offsets. In addition, we develop a cost-efficient local oscillator (LO) aging compensation approach that integrates an improved resistor divider tuning network with embedded software algorithms to mitigate frequency drift caused by crystal aging and maintain reliable reception of weak signals over multiple years. Experimental validation shows that the solution delivers a total gain of 28.19 dB and a noise figure (NF) of 1.87 dB. The receiver satisfies the sensitivity requirement of a bit error rate (BER)