N. Rorsman

An empirical table-based FET model

A new large signal field effect transistor (FET) model combining empirical and table based models was developed and investigated experimentally. The Chalmers empirical model was used as a spline function for the table based model. Combining models improves accuracy and simplifies and speeds extraction. The procedure can be applied for other types of devices.

A 40-GHz integrated quasi-optical slot HFET mixer

We present for the first time a quasi-optical mixer realized as a resistive HFET mixer with an integrated slot antenna. Two different types of HFETs, based on GaAs and InP, are compared for this application. The mixer conversion loss, defined as the measured IF power in the 50 /spl Omega/ load divided by the RF power available at the slot-antenna terminals, is better than 7 dB at LO powers down to 0 dBm. Subharmonic pumping of the mixer is also investigated. This topology has a potential interest for future low-cost millimeter-wave receivers for automobile radar and speed detector systems. >

An integrated millimeterwave BCB patch antenna HEMT receiver

A new integrated millimeterwave patch antenna HEMT receiver for imaging applications is presented. The mixer element is a HEMT working in a resistive mode. We use a relatively thick layer of BenzoCycloButhene (BCB) as dielectric support for the antenna element, and to realize microstrip based circuits. At an RF of 35 GHz we obtain a minimum conversion loss of 8 dB, defined as the IF power dissipated in a 50 /spl Omega/ load divided by the available power from the patch antenna.<<ETX>>

Comparison between Si-LDMOS and GaN-based microwave power transistors

We present in this paper a performance comparison between Si-LDMOSTs with an optimized structure for high breakdown voltage, and AlGaN/GaN power HFETs, based on DC-I/V, small-signal and RF power measurement results.

A LO-rejecting balanced upconverter for communication systems

An LO-rejecting millimeterwave balanced resistive HFET-upconverter based on a dual FET configuration is investigated. Theoretical and experimental results for a 50-60 GHz upconverter as a function of local oscillator power and gate bias voltage, Vgb, is presented. A conversion loss and LO-rejection of 10 dB and 35 dB is experimentally obtained at an LO-power of 5 dBm.