文档介绍：
一种提高捕获灵敏度的降采样滤波方法
刘宇隆,吴晓非**
(北京邮电大学信息与通信工程学院,北京 100876)
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摘要:提高软件 GNSS 接收机的灵敏度是 GNSS 接收机走向实用化的必经之路。提高 GNSS
接收机灵敏度的主要方法是提高捕获质量和消除多径的影响,而提高捕获质量主要是靠改善
基带信号处理算法来获取增益的。信号经过下变频滤波会引入频谱混叠,混叠后的信号将很
难恢复。因此,抗混叠在降采样滤波器中至关重要。本文通过对三种降采样滤波器的性能加
以分析对比,找到最适合系统设计以及最能提高捕获灵敏度的一种降采样滤波方法。
关键词:信息与信号处理;降采样滤波器;CIC 滤波;Farrow 滤波;
中图分类号:TN927+.2
A Method for Improving GNSS Sensitivity by
Down-sampling Filter
LIU Yulong, WU Xiaofei
(School of Information munication Engineering,Beijing University of Posts and
munications, Beijing 100876)
Abstract: The primary way of GNSS receiver to the practical application is to improve its
sensitivity. The main method to enhance the GNSS receiver's sensitivity is improving the quality
of acquisition and eliminating the effects of multi-path. To increase the quality of acquisition is
mainly on the gain introduced by the baseband-signal processing algorithm. Signals filtered by
down-conversion can be introduced with spectrum aliasing which will make the original signals
difficult to recover. Therefore, anti-aliasing is significant for down-sampling filters. In this
article, we analyze the performance of three kinds of down-sampling filters to find the most
suitable down-sampling way for system design and the sensitivity of acquisition improvement.
Key words: munication;Navigation receiver;Sensitivity;Down-sampling Filter