超紧组合导航系统SINS辅助GPS快速捕获技术研究

为提高强干扰和高动态环境下,GPS接收机的灵敏度,缩短首次定位时间及失锁重捕时间,研究了超紧组合导航系统中SINS辅助GPS快速捕获技术。首先,研究了基于FFT的并行快速捕获技术,采用相干累加方法,提高弱信号环境下的捕获灵敏度。采用循环移位、平均采样以及FFT模块复用技术,降低捕获算法的运算量和硬件资源占用率。其次,采用SINS辅助捕获技术,提高接收机高动态环境下的捕获灵敏度,降低首次定位时间和失锁重捕时间。经仿真验证,结果表明,所采用技术是有效的,在高动态和弱信号条件下,接收机捕获时间和灵敏度均显著提高。

Research on GPS Signal Rapid Acquisition Technology of Ultra-Tight Integrated Navigation System Aided by SINS

In order to improve the sensitivity and reduce the time to first fix and lost reacquisition under the circumstance ofstrong Interferences and high dynamic, the GPS signal rapid acquisition technology of ultra-tight integrated navigation system aidedby SINS is researched.Firstly, the parallel rapid acquisition approach based on FFT is adopted and improved.In order to enhance theacquisition sensitivity in the week signal environment, the coherent accumulation method is utilized, and by means of the cyclic shift,average sampling and module reuse technique, the computational load and hardware resource occupy rate of the parallel rapidacquisition approach based on FFT are remarkably reduced.Secondly, the acquisition technique aided by SINS is used to shorten thetime to first fix and lost reacquisition.Finally, the simulation shows that the approaches proposed here are effective.