A ultrawideband low noise amplifier using metamorphic HEMT on organic substrate

The U.S. Federal Communications Commission (FCC) approved the unlicensed use of ultra- wideband (UWB) (range of 3.1-10.6 GHz) for commercial purposes in 2002 [1]. The chip-set for lowband (range 3.1-4.8 GHz) application has already been developed and UWB system for lowband has been evaluated by many companies. But the chip-set for full-band (range of 3.1-10.6 GHz) is on its developing stage. Therefore, various researches on the active devices like LNA, PA and the passives like filter, balun, antenna for full-band application are being performed vigorously [2], [3]. High electron mobility transistors(HEMTs) have played an important role in applications at millimeter wave ranges due to its high speed, low noise characteristics. Focusing on the low noise and high gain characteristics of the devices, applications at 3.1-10.6 GHz, utilizing pseudomorphic HEMT(pHEMT) has reported with excellent performance [4]. Motivated by this we have fabricated balanced low noise amplifier for UWB application utilizing metamorphic InAlAs/InGaAs HEMTs(MHEMT) on GaAs substrate. For the wideband amplifier evaluation, the balanced amplifier with the broadband coupler was designed and realized using multilayer organic substrate based on the ceramic- polymer composite materials developed in this work.