Cancellation techniques for LO leakage and Dc offset in direct conversion systems
Cancellation techniques for LO leakage and Dc offset in direct conversion systems
复制标题
直接变频系统中 LO 泄漏和 DC 偏移的消除技术
DOI：
--
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
V. Lubecke
中科院分区：
文献类型：
--
作者：
Shuhei Yamada;O. Boric;V. Lubecke
本文介绍了直接转换系统的漏极和直流偏置消除技术。混频器输出端的直流偏置，部分原因是由于LO泄漏，通过诱导闪烁噪声降低系统灵敏度，而天线侧的LO泄漏可能会造成额外的干扰。为了减少这些问题，研究了收发器和接收器配置的LO泄漏和直流偏移抵消技术。在接收机配置中使用混频器LO泄漏消除器，实现了零直流偏移和17dB的LO泄漏降低。由于最小的直流偏移，闪烁噪声也减少了19.3 dB。在收发器配置中，同时消除LO泄漏和发射信号泄漏导致闪烁噪声降低21.7dB。这种收发器补偿技术也可用于消除杂波反射。
This paper presents LO leakage and dc offset cancelling techniques for direct conversion systems. Dc offset at the mixer output, partially due to LO leakage, degrades system sensitivity by inducing Flicker noise, while LO leakage on the antenna side may cause additional interference. To reduce these problems, LO leakage and dc offset cancelling techniques were studied for both transceiver and receiver configurations. Using a mixer LO leakage canceller for the receiver configuration, zero dc offset and 17dB of LO leakage reduction were achieved. Flicker noise was also reduced by 19.3 dB as a result of the minimized dc offset. In a transceiver configuration, simultaneous cancellation of LO leakage and transmit signal leakage resulted in a 21.7dB reduction in Flicker noise. This transceiver compensation technique can also be used to cancel clutter reflections.