Design and Development of Mixers for Ultra Wide Band System

Abstract

Mixers are widely used in the analog/RF front end of receivers. The architecture of a super newlineheterodyne receiver typically consists of multiple mixing stages for the purpose of optimizing newlineimage rejection, selectivity, and dynamic range. Down conversion mixer down converts radio newlinefrequency (RF) to intermediate frequency (IF) with the help of local oscillator (LO) frequency newlinePrinciples of mixer operation can be classified in two broad categories ie square law mixers, newlinewhich utilizes the second order I-V characteristics to generate mixing products whereas newlineswitching mixers based on switching of RF signal with LO frequency to produce mixing newlineproducts. When switching mixer are implemented along with transconductance stage to newlineproduce the conversion gain, such mixer are termed as active mixers. Being a nonlinear newlinesystem, mixer dominates the overall performance of the receiver system. Selecting the right newlineRF mixer is a key factor in the overall RF circuit design. There is a continuing demand for newlineincreasing the data rate. newline