摘要：With a lot of millimeter-wave(mm-Wave)applications being issued,wideband circuits and systems have attracted much attention because of their strong applicability and *** this paper,four transformer-based ultra-wideband mm-Wave circuits demonstrated in CMOS technologies are reviewed from theoretical analysis,implementation,to ***,we introduce a mm-Wave low-noise amplifier with transformer-based Gm-boosting and pole-tuning *** achieves wide operating bandwidth,low noise figure,and good gain ***,we review an injection-current-boosting technique which can significantly increase the locking range of mm-Wave injection-locked frequency *** on the injectionlocked principle,we also discuss an ultra-wideband mm-Wave divider with the transformer-based high-order ***,an E-band up-conversion mixer is presented;using the two-path transconductance stage and transformer-based load,it obtains good linearity and a large operating band.