电子科技大学：《射频集成电路 RF Integrated Circuits》课程教学资源（课件讲稿）第七讲 混合器 Mixers

第七讲Mixers 游飞博导/副教授，电子科技大学 feiyou@uestc.edu.cn

第七讲 Mixers 游飞 博导/副教授，电子科技大学 feiyou@uestc.edu.cn

6.1 General Considerations Figure 6.1.Role of mixers in a generic transceiver. LNA Downconversion Mixer IF/Baseband Port F Port LO Port Duplexer LO PA RF LO Port Port IF/Baseband Upconversion Port Mixer Figure 6.2.(a)Mixer using an ideal switch,(b)input and output spectra. V.o RF 3010 C> 00L0 0A-30L000RP-L0 (a) (b时

6.1 General Considerations

6.1 General Considerations Noise and Linearity 。LNA Gain 。Conversion gain Port-to-port Feedthrough Figure 6.3.(a)Feedthrough mechanisms in a mixer,(b)feedthrough paths in a MOS mixer. RF RL LO a b

6.1 General Considerations Noise and Linearity ◦ LNA Gain ◦ Conversion gain Port-to-port Feedthrough

6.1 General Considerations Figure 6.6.Offset generated by LO leakage. VLo oΠ冂 Vaf RL

6.1 General Considerations

6.1 General Considerations Figure 6.7.Effect of RF-LO feedthrough in a direct-conversion receiver. LNA RF-IF Feedthrough LPF RF-LO Feedthrough LO

6.1 General Considerations

6.1 General Considerations Figure 6.8.Effect of LO feedthrough in a heterodyne RX. RF LNA Mixer (JF LO-RF LO-IF Feedthrough Feedthrough LO

6.1 General Considerations

6.1.2 Mixer Noise Figure Figure 6.10.SSB noise figure. Signal Band Spectrum at X Image Band Thermal Noise 0L0 0 0L0 Spectrum at Y 0 0

6.1.2 Mixer Noise Figure

6.1.2 Mixer Noise Figure Figure 6.11.DSB noise figure. Signal Band Spectrum at X Thermal M Noise 0L0 0 Spectrum at Y 0 Typical noise figure meters measure the DSB NF and predict the SSB value by simply adding 3 dB

6.1.2 Mixer Noise Figure Typical noise figure meters measure the DSB NF and predict the SSB value by simply adding 3 dB

6.1.2 Mixer Noise Figure Example 6.3 RF LNA Mixer A BPF @RF 0L01 LO (a) RF Channel LNA LNA Output Noise Output Noise SA SA Smix Smix ORF 0 im RF F 0 (b) (F c

6.1.2 Mixer Noise Figure Example 6.3

NF of Direct-conversion receivers Figure 6.13.Direct-conversion RX for NF calculation. I Mixer LPF LNA NF= SNRin SNRin SNRI SNRO LPF Q Q Mixer

NF of Direct-conversion receivers