1. A Current-Switching Phase Shifter for Millimeter-Wave Applications Chien M. TA, Efstratios SKAFIDAS, and Robin J. EVANS National ICT Australia (NICTA) Department of Electrical and Electronic Engineering The University of Melbourne

2. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France2 Outline Introduction to 60-GHz wireless communications –Phased-array antennae Phase shifter design Results Conclusions

3. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France3 60 GHz wireless communications Unlicensed band –7GHz of bandwidth –Multi-Gbps wireless communications High path loss –88dB free-space loss at 60GHz and 10m distance –Additional attenuation due to oxygen absorption –Phased-array antenna system Low cost –CMOS technology

4. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France4 Steerable antenna system Transmitter: focus output power Receiver: improve SNR, reject interferers

5. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France5 Array factor Beamβ1β1 β2β2 β3β3 Β4Β4 10°0° 180 ° 0°0° 20°0° 270 ° 90 ° 0°0° 30°0° 270 ° 180 ° 90 ° 40°0° 270 ° 180 ° 50°0° 0°0° 0°0° 0°0° 60°0° 90 ° 180 ° 70°0° 90 ° 180 ° 270 ° 80°0° 90 ° 270 ° 0°0°

6. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France6 Published 60-GHz phase shifters [Alalusi CICC 2006] –Vector modulator –Pros: 360° phase control –Cons: high power consumption (~72mW) [Wu EuMIC 2007] –Vector modulator –Pros: continuous, 360° phase control –Cons: lossy (more than 17dB) [Ta CCECE 2008] –Distributed –Pros: negligible power consumption –Cons: lossy, narrow phase control range

7. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France7 Proposed phase shifter architecture Discrete phases determined by length of transmission line Current switching mode

8. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France8 Schematic M 0 : input transconductance, sized and biased for high gain and low noise M 1-4 : switches V 000, V 090, V 180, V 270 : digital input for phase control

9. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France9 Layout 65-nm RF-CMOS Microstrip lines MIM capacitors 525 μ m × 470 μ m

10. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France10 Simulation results 90°

11. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France11 Simulation results (cont’d) Frequency band57 GHz to 66 GHz Power supply1.5 V Power consumption9 mW Output phase0°, 90°, 180°, 270° Power loss< 3 dB Input return loss< −6.7 dB Output return loss< −10 dB Noise figure4.3 to 6.1 dB IIP 3 1.2 dBm

12. June 29, 2009NEWCAS-TAISA 2009, Toulouse, France12 Conclusions and future works Active phase shifter on CMOS –57 to 66 GHz –90°-step output phase –Low noise –Digitally controlled Experimental works –Chip is under fabrication –Phase shifter measurement –Antenna array measurement

13. A Current-Switching Phase Shifter for Millimeter-Wave Applications TA, Chien M., SKAFIDAS, Efstratios, and EVANS, Robin J. National ICT Australia (NICTA) Department of Electrical and Electronic Engineering The University of Melbourne