Simulation, design and integration of 60 GHz Gallium Nitride transceiver into nano-ferrite circulator on-silicon CMOS substrate
In this work the design and integration of 60 GHz monolithic microwave integrated circuit (MMIC) transceiver using 0.15 um Gallium Nitride (GaN) Qorvo process that will support the Wireless Gigabit Alliance (WiGig)/802.11ad radio specifications will be presented. The wideband GaN Power Amplifier (PA) can operate at 60–65 GHz with output power of 27 dBm and large signal gain of 23.5 dB. The wideband Low Noise Amplifier (LNA) has a small signal gain of 16 dB with a noise figure (NF) of 1 dB. The GaN PA and LNA are integrated to a nano-ferrite on-silicon CMOS circulator to construct a single front-end transceiver module.
Ka-band GaN power amplifier MMIC chipset for satellite and 5G cellular communications
Ka-band gallium nitride (GaN) power amplifier monolithic microwave integrated circuits (MMICs) with 2 W driver Amplifier (DRA) MMIC and 8 W high power amplifier (HPA) MMIC have been developed. These MMICs are demonstrated using a 0.15 um GaN high electron mobility transistor (HEMT) technology on silicon carbide (SiC) substrate. At 28 GHz, the three-stage DRA MMIC in-fixture exhibits 25.8 dB of small signal gain and 33.1 dBm of continuous wave (CW) output power, which is sufficient to drive a HPA MMIC. The three-stage HPA MMIC achieves 23.5 dB of small signal gain, a CW output power of 39 dBm, and power added efficiency (PAE) of 26.6% at 28 GHz. The chip areas of the DRA MMIC and HPA MMIC are 4.08 mm2 and 11.22 mm2, respectively.
Experimental Study for a Double-Glazed Forced-Flow Solar Collector/Regenerator
Experimental study of a double-glazed forced-convection solar collector/regenerator for absorption solar cooling is presented. The south facing experimental solar collector/regenerator with 10 deg slope is located at Kaohsiung, Taiwan at 120{degree}19minutesE longitude and 22{degree}34minutesN latitude. The size of the collector is 1 m wide and 7 m long with an effective regeneration area of 0.9 m by 6 m. Previous study for single-glazed forced-convection solar collector/regenerator operated at the same location has shown to have a best day-average efficiency of 17%. In order to raise the system performance, a double-glazed collector/regenerator is constructed such that air can be preheated in the upper channel flow. The preheated air is then conducted into the lower channel where it contacts with the film flow of solar heated lithium-chloride solution and regenerates the solution by carrying out the evaporated water vapor. The preheated air has lower relative humidity but the same humidity ratio since it is sensibly heated. Therefore, the regeneration driving potential is increased. The present study shows that the best day-average efficiency can reach 20% which increases the feasibility of the open-cycle absorption solar cooling system. Effects of controlling parameters on the collector/regenerator performance are studied, and heat and mass transfer correlationsmore » are also presented for design purposes.« less