一种新的零中频调器的应用研究

随着对移动通信收机低功耗，高集成的要求，零中频（IF＝0）结构体现了比传统超外差结构更大的优势，但由于常规零中频接收机采用单正交通道，这种结构对90度相移网络的相位误差较为敏感，从而使得镜象抑制比下降，进而影响了零中频接收机的总体性能指标，文中提出的双正交零中频拓扑结构对正交相移网络的相位误差是不敏感的，从而大大地减小了由相位误差引起的镜象抑制比的下降，进一步提高了零中频接收的优势。

A New Topology of Zero-IF Receiver

With increasing demand for mobile wireless receivers of low power and high integration, the zero-IF receiver demonstrates a greater advantage than the conventional superheterodyne receivers. The normal zero-IF topology with the single quadrature channels is very sensitive to the phase-error of the phase-shift network of LO. It decreases the image-reject ratio (IRR) and limits the applications of this structure. This paper presents a new topology called double-quadrature zero-IF topology, which is insensitive to the phase-error of the phase-shift network of LO and greatly increases the performance of the zero-IF receiver.