一种可变积分时间全球导航定位系统位同步算法

A Global Navigation Satellite System Bit Synchronization Algorithm with Integral Time Variable

提出一种可变积分时间全球导航定位系统(GNSS)位同步算法,该方法改进了固定非相干积分次数的传统最大似然估计方法。在非相干积分过程中对不同候选位置对应的能量进行比较,利用最大能量连续出现在同一候选位置的次数作为观测量,针对不同信号强度自适应地约束非相干积分次数。数值仿真与分析表明,在保证错误估计概率基本不变的前提下,该方法有效地减少了平均估计时间。

A GNSS bit synchronization approach with integral time variable is proposed, which improves conventional maximum likelihood estimating method with fixed non-coherent integral times. The approach introduces the times of max energy consecutively appearing at a same candidate position as an indicator, and constrains the non-coherent integral times self-adaptively for various signal intensities. Numerical simulations validate that the approach is able to reduce the mean estimate time significantly, on the assumption that the estimation error rate is kept almost as low as the conventional method.