电离层扰动对局域增强系统的影响分析

摘要

Differenctial correction method is adopted in GNSS Local Area Augmentation System (LAAS) to improve accuracy .Various ionospheric disturbances with different phe‐nomenon could seriously degrade the performance of LAAS .For ionospheric storm ,the deg‐radation will be caused by the loss of ionospheric delay spatial correlation produced by large delay gradients . For ionospheric scintillation , the effects will be results of two different mechanisms ,one is the degradation of signal quality and measurements quality caused by scintillation ,the other is the loss of ionospheric delay spatial correlation caused by irregulari‐ties in electron density .Measures from various aspects such as receiver design ,system de‐velopment ,and method of integrity realization should be taken to avoid the effects of iono‐spheric disturbance .%卫星导航局域增强系统采用差分技术实现高精度定位能力。电离层扰动现象将对局域增强系统产生严重影响。电离层暴降低了电离层延迟空间相关性，进而影响差分定位的精度；电离层闪烁引起卫星信号质量和测量质量的降低，同时伴随闪烁产生的电离层电子密度不均匀体也会降低电离层延迟的空间相关性，影响差分定位精度。电离层扰动对局域增强系统的影响应通过接收机设计、增强系统设计、完好性实现方法等多方面的改进加以应对。