一种多系统兼容卫星导航抗窄带干扰专用芯片设计

A Multi-constellations Compatibly Anti-narrowband-jamming ASIC Design on Satellite Navigation

卫星导航信号由于其自身特点,经过长距离传输到达地面信号功率十分微弱,所以很容易受到外来同频窄带信号干扰。主要介绍了一种满足北斗、GPS多系统兼容的卫星导航抗窄带专用芯片的设计方案。其采用模数转换、抗干扰处理集成单颗芯片设计架构,可直接替换原有卫星导航终端的A/D芯片,实现抗窄带干扰功能;并着重对抗干扰算法的多系统兼容设计、低功耗干扰检测技术进行了介绍;经流片测试,该芯片抗北斗B1、B3频点和GPS L1频点窄带干扰干信比大于60d B,北斗S频点抗窄带干扰干信比大于55d B,双路同时工作最大功耗小于260m W,可有效满足手持、车载、弹载等小型低功耗卫星导航终端的应用需求。

In view of the characteristics of its own, the power of satellite navigation signal is very weak when it reaches the ground after long distance travel. It is vulnerable to be interfered by the same-frequency narrowband signal. The paper shows a design scheme which can satisfy a kind of multi-constellations such as Beidou, GPS, compatibly anti-narrowband-jam- ming ASIC. It also shows a scheme which integrates A/D conversion, anti-interference processing into a signal chip. It is feasible to directly replace the original A/D chip of terminals and realize the function of anti-jamming. The paper shows an algorithm that can adapt to the different systems of satellite navigation. At the same time, a kind of accurate, low power jamming detection strategy is put forward. It can start anti-jamming processing in due course and hold the lowest power con- sumption when the chip is at work. Thus, it can meet the needs of the small, low power consumption satellite terminals such as the handheld devices, on-board equipment and so on. After the test, the chip can realize the anti-jamming, which indicates JSR （jamming to signal ratio） above 60dB, at B1, B3 frequency points of Beidou and L1 frequency point of GPS, and realize anti-narrowband-jamming, which indicates JSR above 55dB, at S frequency point of Beidou. The largest power consumption is less than 260mW, when the chip can make dual work at the same time.