← 返回 JSSC 论文列表JSSC 2007第12期RF & Wireless65nm
A Blocker Filtering Technique for SAW-Less
提出一种用于无线接收机的主动滤波技术，无需外部声表面波滤波器。
65nm CMOS, 3-dB带宽从220MHz降至4.5MHz, 阻带抑制超过21dB
无线接收机前馈滤波陷波滤波低噪声放大器GSM
▸创新点1：采用前馈滤波路径技术，通过在低噪声放大器（LNA）中引入额外的信号处理路径，有效抑制带外干扰信号，实现了220 MHz到4.5 MHz的带宽缩减，显著提升了接收机的抗干扰能力。
▸创新点2：利用接收机平移环路实现陷波滤波，该方法通过共享主接收机的本地振荡器（LO）信号，简化了电路设计并降低了功耗，同时实现了超过21 dB的阻带抑制性能。
▸创新点3：无需外部表面声波（SAW）滤波器，通过集成化的滤波技术替代传统外置SAW滤波器，降低了系统成本和体积，适用于紧凑型移动通信设备。
▸创新点4：采用65 nm标准CMOS工艺实现原型放大器，展示了该技术在先进制程下的可行性和高性能，为未来无线接收机的集成化设计提供了重要参考。
Abstract
An active filtering technique to remove the out-of- band blockers in wireless receivers is presented. The circuit employs a feed-forward filtering path to produce an arbitrarily narrow frequency response in the low-noise amplifier (LNA), eliminating the need for an external surface acoustic wave (SA W) filter at the receiver front-end. The required notch filtering in the feed-forward path is realized through a receiver translational loop, driven by the same local oscillator (LO) signals used in the main receiver. For the proof of concept, a prototype amplifier in 65 nm standard CMOS, intended for Global System for Mobile Communication (GSM) applications, is implemented. When the filtering is enabled, the amplifier 3-dB bandwidth reduces from 220 MHz to about 4.5 MHz, and a stop-band rejection of over 21 dB is achieved.