摘要
提出了一种针对GPS系统的自适应最大似然比特同步方法。该方法改进了固定非相干累加次数的传统最大似然估计方法,利用归一化的比特能量最大值和次大值差值作为检测量,针对不同载噪比的信号自适应地约束非相干累加次数。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 self-adaptive maximum likelihood bit synchronization approach dedicated for GPS receivers was proposed.The approach introduces a normalized gap between the maximal and the submaximal bit energies to the conventional maximum likelihood method with fixed noncoherent accumulation times as an indicator,to constrain the noncoherent accumulation times for various signal powers self-adaptively.Numerical simulations validate the approach is able to reduce the mean estimation time significantly,while the estimation error rate is guaranteed to be kept almost as low as the conventional method.
出处
《系统仿真学报》
CAS
CSCD
北大核心
2009年第24期7747-7750,7754,共5页
Journal of System Simulation
基金
国家高技术研究发展(863)计划(2007AA12Z344)
关键词
GPS
比特同步
最大似然
自适应
数值仿真
GPS
bit synchronization
maximum likelihood
adaptive
numerical simulations
