Research And Design Of Radio-frequency Front-end Circuit Based On CMOS And BiCMOS

With the rapid increase of wireless communication demand,wireless communica-tion is moving in the direction of high speed and diversity.Ultra wideband(UWB)communication technology transmits data through sending nanosecond ultra-narrow pulse signals.For the high channel capacity,high speed,high spatial resolution,good security,anti-multi-path decline ability,and strong penetrating object,UWB becomes an important technology for Wireless Personal Area Network(WPAN),and attracts wide notice on high speed communication,through-wall imaging,and precise position-ing.In the UWB communication system,radio frequency front end is difficult.It is meaningful for the development of UWB to achieve the design of low power,low cost and high performance transceiver front end integrated circuit.The dissertation mainly focuses on the study of transceiver front end in Impulse radio UWB communication system based on CMOS/BiCMOS process.The main re-search contents and novelties are as follows.(1)An UWB impulse generator consists of ultra-narrow pulse generator and 3rd LC Gaussian bandpass filter is proposed.Firstly,the digital logic cells are used to gen-erate an ultra-narrow pulse with duration of about 100 picoseconds and a bandwidth much greater than interest Then the power of the ultra-narrow pulse can be ampli-fied by a filter drive circuit.Finally,an on-chip 3rd LC Gaussian bandpass filter is used to transfer the ultra-narrow pulse to 3-5GHz UWB impulse,which meets the FCC mask well.The power consumption of the logic device is quite low.And the filter drive circuit only consumes energy in the ulta-narrow pulse duration.Thus this design has the advantages of high integration,low power,and low complexity.(2)A dual band on-off VCO UWB impulse generator is proposed.The narrow rectan-gular pulses with a duration of Ins,which is generated by logic cells,are used to switch on/off the tail current of the dual band LC VCO.And the envelope of the output signal of VCO can be affected by the tail current.UWB impulse which meets the FCC can be obtained.In this design,the dual band switching of the output signal is available.This design has the advantages of high efficiency.And the interference to IEEE 802.11a applications can be avoided,which makes the UWB transmitter more compatible to other system.(3)A millimeter wave signal generator consists of differential Colpitts oscillator and frequency doubler is proposed.A differential Colpitts VCO is designed for 38.5GHz oscillation signal with low phase noise.Then a push-push frequency doubler is im-plemented,which is combined with Colpitts VCO to generate 77GHz oscillation signal.This generator is able to produce two oscillation signals with frequency of 38.5GHz and 77GHz,while the power consumption and phase noise is relatively low.And in this design,the millimeter wave generator is easier to implement for overcoming the limitation of maximum oscillation frequency of transistors.(4)A resistive shunt feedback UWB low noise amplifier with post distortion is pro-posed.The single-stage cascode amplifier is used for low power.And the resisti-ve shunt feedback and dual resonance load network is applied to broaden the band-width of input impedance matching and power gain.Post distortion method is in-troduced to enhance the linearity of the amplifier,while the power gain and noise performance will not be degrade seriously.This design has the advantage of high integration,low power,and high linearity.