The Research On Correlative Blocks Of UWB RF Receiving System

In recent years, Wireless communication technology has been developed rapidly. As an aspect of wireless communication's development, UWB wireless communication technology has been developed quickly.This paper aims at the design demand of UWB receiving system and combines with the advantage of CMOS RFIC。We have designed the important blocks of UWB receiving system, that is Low noise amplifier (LNA) and down-conversion Mixer.Firstly, this paper discussed something about UWB development actuality and characteristic of CMOS RFIC, which explained the importance of designing LNA and Mixer.Secondly, we analyzed the physical characteristic and noise characteristic of MOSFET, which is an important element of CMOS RFIC. At the same time, we discussed smith chart and S-parameter, which are the design foundation of RFIC.Afterwards, according to the design demand of UWB receiving system, LNA is implemented in CMOS RF technology . In the course of designing UWB LNA, we adopted feedback resistor to realize wideband impedance match according to the down-band demand of UWB receiving system. We designed the LNA according to the performance index of its forward power gain, noise figure, linearity, power consumption and so on.We designed UWB down-conversion Mixer in succession. With the use of double balance mixer structure, we achieved wideband impedance match at RF port and selected appropriate switch signal at LO port. During the designing of UWB Mixer, we designed it according to its performance index of frequency conversion gain, noise figure, linearity, power consumption, port isolation and so on.We designed and simulated the circuit by the Star-Hspice software. Furthermore, we analyzed the simulation results. The research results show: the performance indexes of LNA and Mixer can satisfy design demand, which validates design correctness.