A 5.8 GHz Rectenna Design for Microwave Power Transmission

In this era of the Internet of Things, we designed a rectenna working at 5.8 GHz in order to solve the finite things about battery-powered wireless sensor. First, an E-shape embedded microstrip feed antenna by HFSS software has been designed, then a technique called “offset correction” to balance the deviation between theory and simulation was proposed. It effectively spanned the gap between simulation and measure, so that the physical antenna could achieve the design specifications. Then, an impedance measurement model for rectifier circuit was established, which was applied to the vector network analyzer with limited output power. Finally, rectifier’s error was analyzed by “mirror de-embedding impedance measurement”.

Integrated GaAs Diode Technology for Millimeter and Submillimeter-wave Components and Systems

ABSTRACTGaAs Schottky barrier diodes remain a workhorse technology for submillimeter-wave applications including radio astronomy, chemical spectroscopy, atmospheric studies, plasma diagnostics and compact range radar. This is because of the inherent speed of these devices and their ability to operate at room temperature. Although planar (flip-chip and beam-lead) diodes are replacing whisker contacted diodes throughout this frequency range, the handling and placement of such small GaAs chips limits performance and greatly increases component costs. Through the use of a novel wafer bonding process we have fabricated and tested submillimeter-wave components where the GaAs diode is integrated on a quartz substrate along with other circuit elements such as filters, probes and bias lines. This not only eliminates the cost of handling microscopically small chips, but also improves circuit performance. This is because the parasitic capacitance is reduced by the elimination of the GaAs substrate and the electrical embedding impedance seen by the diodes is more precisely controlled. Our wafer bonding process has been demonstrated through the fabrication and testing of a fundamental mixer at 585 GHz (Tmix < 1200K) and a 380 GHz subharmonically pumped mixer (Tmix < 1000K). This paper reviews the wafer bonding process and discusses how it can be used to greatly improve the performance and manufacturability of submillimeter-wave components.

Wide-Band Tunerless Mixer Mounts for 100 GHz and 150 GHz SIS receivers

The performance of the new SIS receiver systems at the Nobeyama Millimeter Array are described. These receivers operate at 100 GHz and 150 GHz bands and tunerless mixer mounts have been adopted. These receivers show very low noise temperature (< 50 K) over a very wide frequency range because of the large embedding impedance range.