1132 半导体学报 第29卷 ,70(a) Table 1 Performance comparison of O-mixer and G-mixer G-mixer,IRR2 60 Parameter CG IIP3 NF IRR1 IRR2 FOM /mA /dB /dBm /dB /dB /dB /dB 50 Q-mixer 2.5611.2 10.3 17.51073314.9 40 Q-mixer,IRR2 G-mixer 2.45 8.4 10.9 20 27 5012.9 30 2.5 Summary 20 … G-mixer,IRRI 10 The simulated performances of the Q-mixer and 0.70.80.91.01.11.21.3 Relative transistor gate length G-mixer are summarized and compared in Table 1. The RF and LO frequency are 1.005GHz and 1GHz respectively,and the LO amplitude is 5dBm,which is 55 (b) a typical value in receivers.IRRI and IRR2 are both 50 simulated with a relative transistor gate length of 1.1.Linearity figures-of-merit (FOM)defined as G-mixer,IRR2 10lg(OIP3(mW)/Pde(mW))are also calculated for 40 G-mixer.IRRI Q-mixer,IRR2 the two topologies,which indicates the higher per- formance of the Q-mixer in commutating mode. 30 在AAAA-AA-AAA-A 3 Circuit design and optimization 0.2 0.40.60.8 1.0 LO amplitude/V The presented quadrature down-conversion mixer Fig.6 (a)Simulated IRR versus relative transistor gate for UHF RFID readers is shown in Fig.7.According length.with LO amplitude of 5dBm:(b)Simulated IRR versus to the analysis in Section 2,the Q-mixer topology is a- LO amplitude,with relative transistor gate length of 1.I dopted here to consume less power while achieving sistor gate length in the I path to that in the Q path. the same performance as the G-mixer topology.More- As expected,the IRR of the Q-mixer is immune to over,this topology also relaxes the design trade-offs mismatch in the transconductor stage but more sensi- between NF,CG,and linearity.To get high CG and tive to mismatch in the switching stage.However,as low NF,higher bias current is expected in the the LO amplitude increases,the switching in the O- transconductor stage,while lower bias current is pre- mixer will be more ideal,and the loss of image rejec- ferred in the switching stage.Because previous works tion due to the switching stage will be reduced fur- used current bleeding or folded structures to solve this ther,as shown in Fig.6(b). problem,they either increased the circuit complexity I-Path Q-Path IFL-o IFQ+ LOI+o- LOQ LOQ RF- G Fig.7 Presented quadrature down-conversion mixer with shared transconductor stage半 导 体 学 报 第２９卷 犉犻犵．６ （犪）犛犻犿狌犾犪狋犲犱 犐犚犚 狏犲狉狊狌狊狉犲犾犪狋犻狏犲狋狉犪狀狊犻狊狋狅狉 犵犪狋犲 犾犲狀犵狋犺，狑犻狋犺犔犗犪犿狆犾犻狋狌犱犲狅犳５犱犅犿；（犫）犛犻犿狌犾犪狋犲犱犐犚犚狏犲狉狊狌狊 犔犗犪犿狆犾犻狋狌犱犲，狑犻狋犺狉犲犾犪狋犻狏犲狋狉犪狀狊犻狊狋狅狉犵犪狋犲犾犲狀犵狋犺狅犳１１ 狊犻狊狋狅狉犵犪狋犲犾犲狀犵狋犺犻狀狋犺犲犐狆犪狋犺狋狅狋犺犪狋犻狀狋犺犲犙狆犪狋犺． 犃狊犲狓狆犲犮狋犲犱，狋犺犲犐犚犚 狅犳狋犺犲 犙犿犻狓犲狉犻狊犻犿犿狌狀犲狋狅 犿犻狊犿犪狋犮犺犻狀狋犺犲狋狉犪狀狊犮狅狀犱狌犮狋狅狉狊狋犪犵犲犫狌狋犿狅狉犲狊犲狀狊犻 狋犻狏犲狋狅 犿犻狊犿犪狋犮犺犻狀狋犺犲狊狑犻狋犮犺犻狀犵狊狋犪犵犲．犎狅狑犲狏犲狉，犪狊 狋犺犲犔犗 犪犿狆犾犻狋狌犱犲犻狀犮狉犲犪狊犲狊，狋犺犲狊狑犻狋犮犺犻狀犵犻狀狋犺犲 犙 犿犻狓犲狉狑犻犾犾犫犲犿狅狉犲犻犱犲犪犾，犪狀犱狋犺犲犾狅狊狊狅犳犻犿犪犵犲狉犲犼犲犮 狋犻狅狀犱狌犲狋狅狋犺犲狊狑犻狋犮犺犻狀犵狊狋犪犵犲 狑犻犾犾犫犲狉犲犱狌犮犲犱犳狌狉 狋犺犲狉，犪狊狊犺狅狑狀犻狀犉犻犵６（犫）． 犜犪犫犾犲１ 犘犲狉犳狅狉犿犪狀犮犲犮狅犿狆犪狉犻狊狅狀狅犳犙犿犻狓犲狉犪狀犱犌犿犻狓犲狉 犘犪狉犪犿犲狋犲狉 犐犇犇 ／犿犃 犆犌 ／犱犅 犐犐犘３ ／犱犅犿 犖犉 ／犱犅 犐犚犚１ ／犱犅 犐犚犚２ ／犱犅 犉犗犕 ／犱犅 犙犿犻狓犲狉 ２．５６ １１．２ １０．３ １７．５ １０７ ３３ １４．９ 犌犿犻狓犲狉 ２．４５ ８．４ １０．９ ２０ ２７ ５０ １２．９ ２．５ 犛狌犿犿犪狉狔 犜犺犲狊犻犿狌犾犪狋犲犱狆犲狉犳狅狉犿犪狀犮犲狊狅犳狋犺犲犙犿犻狓犲狉犪狀犱 犌犿犻狓犲狉犪狉犲狊狌犿犿犪狉犻狕犲犱犪狀犱犮狅犿狆犪狉犲犱犻狀 犜犪犫犾犲１． 犜犺犲犚犉犪狀犱犔犗犳狉犲狇狌犲狀犮狔犪狉犲１００５犌犎狕犪狀犱１犌犎狕 狉犲狊狆犲犮狋犻狏犲犾狔，犪狀犱狋犺犲犔犗犪犿狆犾犻狋狌犱犲犻狊５犱犅犿，狑犺犻犮犺犻狊 犪狋狔狆犻犮犪犾狏犪犾狌犲犻狀狉犲犮犲犻狏犲狉狊．犐犚犚１犪狀犱犐犚犚２犪狉犲犫狅狋犺 狊犻犿狌犾犪狋犲犱 狑犻狋犺 犪狉犲犾犪狋犻狏犲狋狉犪狀狊犻狊狋狅狉犵犪狋犲犾犲狀犵狋犺 狅犳 １１．犔犻狀犲犪狉犻狋狔 犳犻犵狌狉犲狊狅犳犿犲狉犻狋 （犉犗犕）犱犲犳犻狀犲犱 犪狊 １０犾犵（犗犐犘３（犿犠）／犘犱犮（犿犠））犪狉犲 犪犾狊狅 犮犪犾犮狌犾犪狋犲犱犳狅狉 狋犺犲狋狑狅狋狅狆狅犾狅犵犻犲狊，狑犺犻犮犺犻狀犱犻犮犪狋犲狊狋犺犲犺犻犵犺犲狉狆犲狉 犳狅狉犿犪狀犮犲狅犳狋犺犲犙犿犻狓犲狉犻狀犮狅犿犿狌狋犪狋犻狀犵犿狅犱犲． ３ 犆犻狉犮狌犻狋犱犲狊犻犵狀犪狀犱狅狆狋犻犿犻狕犪狋犻狅狀 犜犺犲狆狉犲狊犲狀狋犲犱狇狌犪犱狉犪狋狌狉犲犱狅狑狀犮狅狀狏犲狉狊犻狅狀犿犻狓犲狉 犳狅狉犝犎犉犚犉犐犇狉犲犪犱犲狉狊犻狊狊犺狅狑狀犻狀犉犻犵７．犃犮犮狅狉犱犻狀犵 狋狅狋犺犲犪狀犪犾狔狊犻狊犻狀犛犲犮狋犻狅狀２，狋犺犲犙犿犻狓犲狉狋狅狆狅犾狅犵狔犻狊犪 犱狅狆狋犲犱犺犲狉犲狋狅犮狅狀狊狌犿犲犾犲狊狊狆狅狑犲狉 狑犺犻犾犲犪犮犺犻犲狏犻狀犵 狋犺犲狊犪犿犲狆犲狉犳狅狉犿犪狀犮犲犪狊狋犺犲犌犿犻狓犲狉狋狅狆狅犾狅犵狔．犕狅狉犲 狅狏犲狉，狋犺犻狊狋狅狆狅犾狅犵狔犪犾狊狅狉犲犾犪狓犲狊狋犺犲犱犲狊犻犵狀狋狉犪犱犲狅犳犳狊 犫犲狋狑犲犲狀犖犉，犆犌，犪狀犱犾犻狀犲犪狉犻狋狔．犜狅犵犲狋犺犻犵犺 犆犌 犪狀犱 犾狅狑 犖犉，犺犻犵犺犲狉 犫犻犪狊 犮狌狉狉犲狀狋 犻狊 犲狓狆犲犮狋犲犱 犻狀 狋犺犲 狋狉犪狀狊犮狅狀犱狌犮狋狅狉狊狋犪犵犲，狑犺犻犾犲犾狅狑犲狉犫犻犪狊犮狌狉狉犲狀狋犻狊狆狉犲 犳犲狉狉犲犱犻狀狋犺犲狊狑犻狋犮犺犻狀犵狊狋犪犵犲．犅犲犮犪狌狊犲狆狉犲狏犻狅狌狊狑狅狉犽狊 狌狊犲犱犮狌狉狉犲狀狋犫犾犲犲犱犻狀犵狅狉犳狅犾犱犲犱狊狋狉狌犮狋狌狉犲狊狋狅狊狅犾狏犲狋犺犻狊 狆狉狅犫犾犲犿，狋犺犲狔犲犻狋犺犲狉犻狀犮狉犲犪狊犲犱狋犺犲犮犻狉犮狌犻狋犮狅犿狆犾犲狓犻狋狔 犉犻犵．７ 犘狉犲狊犲狀狋犲犱狇狌犪犱狉犪狋狌狉犲犱狅狑狀犮狅狀狏犲狉狊犻狅狀犿犻狓犲狉狑犻狋犺狊犺犪狉犲犱狋狉犪狀狊犮狅狀犱狌犮狋狅狉狊狋犪犵犲 １１３２