Systems and methods for enhancing GNSS numerically controlled oscillators

摘要

Systems and methods for enhancing numerically controlled oscillators are provided. In certain embodiments, a numerically controlled oscillator enhancer includes a desired rate interface configured to receive a desired numerically controlled oscillator rate from an external device and a closest quantized rate identifier configured to identify a closest quantization rate that is closest to the desired numerically controlled oscillator rate. Further, the numerically controlled oscillator enhancer includes a quantization rate corrector configured to identify the quantization rate correction that, when applied to the closest quantization rate, constrains an accumulated quantization error within an error range and a rate output configured to output a corrected quantized numerically controlled oscillator rate.

主权项

1. A global navigation satellite system receiver, the receiver comprising:
a front end configured to receive global navigation satellite system signals and mix the received global navigation satellite system signals to intermediate frequency signals; a code and carrier remover configured to mix the intermediate frequency signals to baseband signals and remove codes from the baseband signals; a code numerically controlled oscillator configured to provide a code oscillating signal to the code and carrier remover, wherein the code and carrier remover uses the code oscillating signal to remove codes from the baseband signal; a carrier numerically controlled oscillator configured to provide a carrier oscillating signal to the code and carrier remover, wherein the code and carrier remover uses the carrier oscillating signal to mix the intermediate frequency signals to the baseband signals; a control block, wherein the control block monitors the baseband signal to determine a desired code numerically controlled oscillator rate and a desired carrier numerically controlled oscillator rate; a code numerically controlled oscillator enhancer configured to receive the desired code numerically controlled oscillator rate from the control block, wherein the code numerically controlled oscillator enhancer selects a quantized code oscillator rate for the code numerically controlled oscillator based on an accumulated quantization error; and a carrier numerically controlled oscillator enhancer configured to receive the desired carrier numerically controlled oscillator rate from the control block, wherein the carrier numerically controlled oscillator enhancer selects a quantized carrier oscillator rate for the carrier numerically controlled oscillator based on the carrier accumulated quantization error.