Hardware receiver and method for achieving GNSS-R phase difference extraction

Abstract

The invention relates to a hardware receiver and method for achieving GNSS-R phase difference extraction. The hardware receiver comprises a code phase difference fast rough measurement module, a code phase difference accurate measurement module, a carrier phase difference estimation module, and a full-phase transformation and carrier phase difference correction module. The method is based on a FPGA and a DSP, achieves reflected signal effective coherent integration by using a FIFO to perform data time delay, uses a code phase difference rough measured value as an initial computation code phase different accurate measured value of a Gauss-Newton iteration algorithm, guides carrier phase difference solution by using a code phase difference accurate measured value, computes the initial phase values of a direct signal and a reflected signal by using full-phase FFT, and corrects a carrier phase difference final result by means of the comparison of the initial phase values. A hardware device may accurately process acquired direct navigation signals and reflected navigation signals in real time and may correct a carrier phase difference measurement error caused by a reflection plane.

Description

technical field [0001] The invention belongs to the technical field of using global satellite navigation system reflection signals (GNSS-R signals) for earth and ocean remote sensing or passive target detection, and relates to a new method for extracting the code phase difference and carrier phase of direct navigation signals and reflection signals Poor hardware receiver and method. Background technique [0002] In the application field of satellite navigation signal reflection signal (GNSS-R signal), special application functions are realized mainly through the signal characteristic difference between navigation direct signal and reflection signal, such as code phase difference, carrier phase difference, and related power waveform changes, such as Land and ocean remote sensing, passive target detection, etc. In the field of GNSS-R research and application, due to the complex receiving and processing process of reflected signals, software receivers are mainly used to receiv...

AI Technical Summary

Problems solved by technology

In practical application, the accuracy of DCF method is poor, and the accuracy of iterative estimation method is higher, but the amount of calculation required is larger

[0006] 3. After the navigation signal is reflected by the reflective surface, the carrier phase of the signal will change due to the reflective surface. The undulating sea surface and high-speed moving aircraft may cause changes in the carrier phase of the reflected signal, such as signal phase breaks, etc.

However, the current software and hardware GNSS-R receivers cannot estimate and eliminate the carrier phase change caused by the reflection process when estimating the carrier phase difference between the direct and reflected signals.

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