Palash Roy

Fully integrated LTE-Advanced band-switchable high-gain CMOS power amplifier

This paper presents a fully integrated multiband high gain CMOS tunable power amplifier (PA) for 760–960 MHz, 1.3–1.6 GHz, 1.7–2.34 GHz, 2.35–2.81 GHz, thus, covering 33 Long Term Evolution-advanced (LTE-a) bands for cellular applications. The 3 mm × 1.5 mm PA chip fabricated using 0.13 um CMOS process exhibits peak output power of 21 dBm / 23.2 dBm / 21 dBm / 23 dBm with maximum gain of 34 dB / 42 dB/ 42 dB/ 40 dB.

A variable high gain and high dynamic range CMOS phase shifter for phased array beamforming applications

This paper presents for the first time the development of a variable high gain phase shifter with the capability of high dynamic gain control using 0.18 μm CMOS process in the frequency range of 1 ~ 3 GHz to be used with conformal phased array beamforming antenna for wireless communication applications. The vector modulator based phase shifter has an integrated variable gain amplifier co-designed with the phase shifter circuitry in order to vary gain along with phase which are essential to recover the degraded radiation pattern due to the conformal shaping of the phased array antenna in the entire 360° range. The design shows the state-of-the-art performances including 20.5 dB gain with 30dB gain control range, continuous phase rotation of 360° with RMS phase error of 2° at 2.2 GHz. The chip area comprising all pads is 1.35 mm2.

A single-chip CMOS transmitter for automatic dependent surveillance-broadcast (ADS-B) system

This paper presents a single-chip CMOS transmitter for Automatic Dependent Surveillance-Broadcast (ADS-B) system, for the first time, operating at both 978 MHz Universal Access Transceiver (UAT) mode and 1090 MHz Extended Squitter (1090 ES) mode. The 1.9 mm × 0.84 mm transmitter chip fabricated using 0.18 um CMOS process exhibits peak output power of 17 dBm at 978 MHz with 128 MHz bandwidth, thus providing a big advantage of reduction in size and cost over the state-of-the-art ADS-B technology.