GPS软件接收机码环鉴相器研究

摘要

The tracking performances of three discriminator functions based on Delay Lock Loop ( DLL) were studied; Early Minus Late Power ( EML Power) , Early Minus Late Envelope ( EML Envelope) and Dot Power ( DOT). A new mode that shifting discriminator function based on the tracking state is proposed to improve the performance of tracking loop. The experimental results tested by actual IF data show modified discriminator tracking signal effectively.%分析非相干前减后功率法、非相干前减后幅值法和相干点积功率法三种码环鉴相函数的跟踪性能.改变整个通道采用单一码环鉴相函数的模式,在牵引状态采用非相干前减后功率法,稳定跟踪阶段采用相干点积功率法,改善了跟踪性能,并用中频数据进行了验证.