A Four Channel Impulse Radio Ultrawideband (IR-UWB) Front End Transmitter System for a 2 × 2 Quadrature Based Phased Array Antenna Designed in 180 nm CMOS Process

One of the challenges of integrating phased array antennas with an IR-UWB transmitter system is to transmit impulse signals at various phases to achieve different beam steering angles and transmit the highest possible power efficiently to the antenna arrays to enhance the gain of the antenna. Prior works that demonstrated wireless power transmission schemes using ultrawideband signals, were limited in terms of the transmitter system design along with the antenna design optimization to deliver the highest power and improve the PTE. To overcome these constraints, this paper presents the design of a four-channel IR-UWB transmitter system for a 2 X 2 quadrature phased array antenna using the standard 180 nm CMOS process. The system consists of a voltage-controlled ring oscillator (VCRO) which achieves a linear frequency range of 2.31 – 8.03 GHz by tuning the control voltage from 0.1 – 0.9 V. The designed impulse generator can generate as low as 435 ps impulse signal with 100 MHz pulse repetition frequency (PRF). The impulse is delayed by controlling the delay control voltages of the two double-inverter based delay blocks thus achieving a delay range of 160 to 260 ps. The designed class-C power amplifier can deliver as high as 32.2 dBm output power at 3 GHz achieving a gain of 14.2 dB and a power added efficiency (PAE) of 50.1 %.