this paper presents a design of an uwb downconversion integrated cmos resistive ring mixer with linear voltage regulator (lvr), to supply required biasing voltages for the mixer section. the designed mixer circuit has been optimized for using in heart rate extraction system with microwave doppler radar at 2.4ghz frequency. this mixer needs 2 dc bias voltages equal to 0.5 and 1 volts for its bes...

(not more than 200 words) This report describes the 94 GHz imaging radar system that has been developed and used within the IR/mm project during the years 2001-2003. The new system, which is based on active gate mixers (GaAs MMIC), shows higher performance than an earlier used system, which was based on resistive mixers (InP HEMT). The conversion loss and pumping power requirement have both bee...

This paper presents an IDS(VGS,VDS) model to represent PHEMT behavior in the reverse ) 0 ( < DS V , and forward zone ) 0 ( > DS V . The model predicts with high accuracy the measured data as well as higher orders derivatives of the transconductance over a large range of VDS bias. These characteristics are important for the analysis of intermodulation distortion using harmonic balance or Volterr...

We have demonstrated a low noise superconducting MgB2 hot electron bolometer (HEB) mixer working at the frequency of 5.3 terahertz (THz) with 20 K operation temperature. The consists 7 nm thick submicrometer bridge contacted spiral antenna to couple THz radiation through high resistive Si lens, and it has critical temperature 38 K. By using hot/cold blackbody loads Mylar beam splitter all in va...

The isolation of the two-dimensional material graphene, a single hexagonal sheet of carbon atoms, is believed to trigger a revolution in electronics. Theory predicts unprecedented carrier velocities in ideal graphene, from which ultrahigh speed graphene field effect transistors (GFETs) are envisioned. In this thesis, the prospects of GFETs for microwave receivers are investigated with the empha...

Graphene is a one-atom-thick sheet of carbon with numerous impressive properties. It is a promising material for future high-speed nanoelectronics due to its intrinsic superior carrier mobility and very high saturation velocity. These exceptional carrier transport properties suggest that graphene field effect transistors (G-FETs) can potentially outperform other FET technologies. This doctoral ...

This paper describes design techniques for both single-ended and differential VCOs, with examples shown fabricated in GaAs MMIC processes. The potential uses and advantages of the differential over the conventional single-ended approach are discussed. Introduction Voltage Controlled Oscillators (VCOs) are widely used as signal sources in RF and microwave communication systems. Fully monolithic ...

Two packaged low noise amplifiers for the 0.3-4 GHz frequency range are described. The amplifiers can be operated at temperatures of 300-4 K and achieve noise temperatures in the 5 K range (<0.1 dB noise figure) at 15 K physical temperature. One amplifier utilizes commercially available, plastic-packaged SiGe transistors for first and second stages; the second amplifier is identical except it u...