The Design Of LNA And VCO For 2.4GHz RF Receiver In 0.25μm CMOS Process

With the development of the technology of wireless communication, the dream of data communication anywhere and anytime has been realized primarily. At the same time, the demand has been on a great upsurge for higher-rate, larger-capability and higher-performance of wireless communication systems. Under such circumstances, researches in the field of radio and wireless communication IC become more and more active. Now there exist several kinds of wireless data communication standard, for example, in 2.4GHz ISM-band there are 802.1 l(b/g) standard, Bluetooth and home RF etc.With the progress of CMOS technology, the characteristic size is shrinking, which can meet the requirements of several ten GHz RFIC. At the same time, the improvement of device model, the appearance of high performance passive IC device and especially the realization of inductors in chip make the RF front-back function circuits integrating into single chip possible. So, the competition ability of CMOS technology in RFIC is largely enhanced by all of these progresses.In this thesis it is presented that the design of LNA and VCO for IEEE 802.11b/g WLAN receiver in a 0.25μm CMOS process. For the 2.4GHz receiver the RF is tunable from 2.4 to 2.483GHz and the IF is 480MHz.The inductor and capacitor in CMOS process is an important issue in designing LNA and VCO. The model of inductor and capacitor are introduced in the first. With the help of software ASITIC, different kinds of inductors are simulated to fit the requirement of the design. Starting from the noise analysis, the relationship of the noise factor of circuit and the width of MOSFET is deduced, which is quite important for LNA. In the VCO designing, the model of linear time dependent noise is adopted to calculate the phase noise. The quantitative relationship of phase noise and other parameters is obtained. To solve the contradiction of gain and tuning range of VCO, the self-adjusted-discrete VCO is introduced, by which the gain and phase noise of VCO can be largely decreased in wide tuning range. To reach better performance of circuit, the bias circuit of band gap reference is adopted which makes the bias voltage and current independent of the power supply and temperature.Several key simulation results are achieved in the work of the thesis: the voltage control oscillator (VCO) has an output frequency range from 1.8 to 2.28GHz with...