摘要
在0.18μm CMOS工艺下设计了一种用于无线传感器网络的具有低功耗、低中频特性的2.4GHz射频前端。该射频前端由一个共栅结构的可变增益低噪声放大器(VGLNA)和一个低功耗折叠正交吉尔伯特结构混频器构成,内部同时集成了一个给混频器提供IQ差分本振信号的二分频器以及一组缓冲器。其低噪声放大器具有高、低两个增益模式。为了弥补共栅低噪声放大器在增益和噪声等性能方面的不足,选取有一定增益的折叠吉尔伯特有源混频器结构。对共栅结构的低噪声放大器的设计过程、相关负载电感建模过程及混频器设计过程进行了详细分析,对整个射频前端芯片进行了测试,测试结果显示,射频前端核心电路在1.8V电源电压下工作电流为3.2mA,功耗为5.76mW;在高增益模式下,具有26dB的转化电压增益及8dB的噪声系数;在低增益模式下,输入1dB压缩点为-20dBm。
A 2.4GHz low power low-IF RF frontend for wireless sensor networks was designed and implemented in a 0.18~m CMOS technology. The RF frontend consists of a variable gain low noise amplifier (VG-LNA) , a low pow- er folded Gilbert quadrature mixer and a divide-by-two circuit which generates the differential quadrature LO signals for the quadrature balanced mixer. The VG-LNA has the high gain mode and the low gain mode. The folded Gilbert active mixer was chosen to make up for the weakness on gain and noise figure of the common gate LNA. The design of the common gate LNA and the inductor modeling for this LNA, and the design of the mixer, were analyzed in de- tail, and the RF frontend was tested and measured. The measurement results showed that the frontend achieved the 26dB voltage conversion gain and the 8dB noise figure at the high gain mode, and the -20dBm input referenced l dB compression point at the low gain mode, while its DC operating current and power consumption were 3.2mA and 5.76mW under a 1.8V voltage supply.
出处
《高技术通讯》
CAS
CSCD
北大核心
2013年第4期413-420,共8页
Chinese High Technology Letters
基金
863计划(2007AA0122A7)
江苏省科技成果转化基金(BA2010073)资助项目