A 433 MHz low noise amplifier applied in ASK receiver has been designed in UMC 0.18 μm standard CMOS process.The amplifier employs differential cascade structure with inductive source degeneration,implements single input and differential output,and avoids using balun when connect to mixer.This low noise amplifier provides a forward gain of 18.2 dB with a noise figure of only 1.65 dB,so this LNA can largely improves performance of receiver.Input and output matching is-28 dB and-24 dB,input third-order intercept point is-9.8 dBm.The total power dissipation is 6.5 mW from a 1.8 V supply.The LNA chip area is 0.6 mm×0.9 mm.

A dual-band voltage-controlled oscillator applied to IEEE 802.11 a/b/g and Bluetooth multistandard zero-IF transceivers is proposed.Power consumption is minimized by means of current reuse that two VCOs operating in different bands is stacked with series connection.The simulated phase noise is-126.2 and-120.1 dBc/Hz at 1 MHz offset from 2.44 and 5.23 GHz carriers with power consumption of 12.22 mW,which completely meets the demand for IEEE 802.11a/b/g and Bluetooth standards.The simulation is performed in Agilent ADS and this circuit with chip area of 1.18 mm×0.67 mm will be implemented by 0.18 μm CMOS process.