A 250-Mb/s Data Rate IR-UWB Transmitter Using Current-Reused Technique

This paper describes the design, simulation, implementation and testing of an impulse-radio ultra-wideband bi-phase shift keying (IR-UWB BPSK) transmitter, working in the frequency range between 3.5 and 6.5 GHz. The transmitter has been optimized to achieve the maximum distance of transmission while working within the power limits specified by the Federal Communications Commission (FCC). In this transmitter, the IR-UWB signal is generated by differentiating a Gaussian signal and then amplifying the differentiated signal. This is accomplished using a current-reused power amplifier circuit as both the differentiator and amplifier. A theoretical analysis is performed to obtain the relationship between the output amplitude and the data rate of the transmitted signal. The simulations and experimental results of the IR-UWB BPSK transmitter, implemented in a 180-nm CMOS process, are then presented. The transmitter was found to function at data rates up to 250 Mb/s with a maximum peak amplitude of 0.5 V. The dc energy consumption of the transmitter is 86 pJ/pulse. The energy efficiency is 26.2% for the pulsewidth of 1 ns. The experimental results show that power spectral density of the transmitter agrees with the simulated results and is within the FCC limits. The total core area of the chip is 0.22 mm
²
.