摘要
由于多普勒频移和载波频差引起的大频偏问题对数字移动通信系统的性能影响很大，文中在研究多普勒频移（ＤＦＳ）校正数字滤波算法的基础上，设计并实现了传输速率为４．８ｋｂｉｔ／ｓ的四相差分相移键控调制（ＤＱＰＳＫ）的全数字接收机，并且对存在多普勒频漂和载波频差时的性能进行了分析和测试。研究结果表明，该接收机在结构上更为简单、实现更为有效，该接收机抗频偏能力接近传输符号速率，并具有较强的抗ＤＦＳ频漂能力。
The problem of large frequency shift due to doppler frequency shift (DFS) and carrier frequency bias greatly affects the performance of digital mobile communication systems. Based on the correction algorithms via digital filter, this paper deals with the design and realization of an all digital receiver with differential quadrature phase shift keying (DQPSK) modulation scheme, which has a data rate of 4.8 kbit/s. Furthermore, the analysis and testing of the system performance in present of DFS and carrier frequency bias are also described. The results have shown that this novel receiver is simple in structure and available in implementation. The receiver is so robust to DFS, as up to such that the DFS is near the transmission symbol rate. Meanwhile, it has much stronger ability against DFS shift effects.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
1997年第9期24-28,共5页
Journal of Tsinghua University(Science and Technology)
基金
国家自然科学基金
关键词
全数字接收机
数字移动通信
DQPSK
大频偏
Doppler frequency shift (DFS), carrier frequency bias, all digital receiver, DFS correction algorithm
