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.
A comparison of experimental thermal stratification parameters for an oil/pebble-bed thermal energy storage (TES) system during charging
Six different experimental thermal stratification evaluation parameters during charging for an oil/pebble-bed TES system are presented. The six parameters are the temperature distribution along the height of the storage tank at different time intervals, the charging energy efficiency, the charging exergy efficiency, the stratification number, the Reynolds number and the Richardson number. These parameters are evaluated under six different experimental charging conditions. Temperature distribution along the height of the storage tank at different time intervals and the stratification number are parameters found to describe thermal stratification quantitatively adequately. On the other-hand, the charging exergy efficiency and the Reynolds number give important information about describing thermal stratification qualitatively and should be used with care. The charging energy efficiency and the Richardson number have no clear relationship with thermal stratification.