A Q-band miniaturized uniplanar MMIC HEMT mixer

A miniaturized uniplanar GaAs MMIC HEMT mixer is proposed based on a compact multifunction transition structure. By the independence nature of the coplanar-waveguide (CPW) mode and the coplanar-stripline (CPS) mode, a compact transition which converts the CPW mode into the CPS mode is realized. This transition structure also has the functions of 180/spl deg/ hybrid, RF and LO diplexer, and bandpass filter. Thus the size of the proposed mixer may be drastically reduced, and the LO-to-IF and LO-to-RF isolations and RF conversion gain are excellent. This mixer is designed to operate with RF frequency from 35 to 40 GHz, IF frequency from 0.5 to 6 GHz, and LO frequency at 35 GHz. The lower sideband conversion gain is about 5 dB, the single-sideband (SSB) noise figure is 6.5 dB, the isolations are all better than 30 dB, and the size of the mixer is much compact than those of the conventional mixers.

[1]  Yo-Shen Lin,et al.  Novel lumped-element coplanar waveguide-to-coplanar stripline transitions with low-pass and high-pass characteristics , 2002, 2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278).

[2]  A. Tessmann,et al.  Avoiding cross talk and feed back effects in packaging coplanar millimeter-wave circuits , 1998, 1998 IEEE MTT-S International Microwave Symposium Digest (Cat. No.98CH36192).

[3]  M. Kintis,et al.  Design and performance of a new uniplanar diode mixer , 2000 .

[4]  Huei Wang,et al.  A full-wave analysis model for uniplanar circuits with lumped elements , 2003 .

[5]  Yo-Shen Lin,et al.  Novel lumped-element uniplanar transitions , 2001 .

[6]  Huei Wang,et al.  A Miniaturized Uniplanar Singly-Balanced Mixer , 2002, 2002 32nd European Microwave Conference.

[7]  E. Rius,et al.  A novel uniplanar bi-phase (0/spl deg/-180/spl deg/) modulator/mixer , 1995, Proceedings of 1995 IEEE MTT-S International Microwave Symposium.

[8]  Sanjay Raman,et al.  A 60-GHz uniplanar MMIC 4/spl times/ subharmonic mixer , 2002 .

[9]  Ke Wu,et al.  A novel uniplanar balanced subharmonically pumped mixer for low-cost broadband millimeter-wave transceiver design , 2000, 2000 IEEE MTT-S International Microwave Symposium Digest (Cat. No.00CH37017).

[10]  S. Raman,et al.  A 60 GHz uniplanar MMIC 4X subharmonic mixer , 2001, 2001 IEEE MTT-S International Microwave Sympsoium Digest (Cat. No.01CH37157).