System-level integration and simulation of ultra wideband receiver front-end

To determine the most appropriate design for ultra wideband (UWB) receiver front-end, a study was conducted on the designs of wideband antennas, wideband filters, and wideband amplifiers. Previous works on these devices have been analysed and compared for the following major parameters, which are antenna return loss, antenna bandwidth, filter bandwidth, filter insertion loss, filter return loss, amplifier gain, amplifier bandwidth, amplifier return loss, and amplifier noise figure. This work is to integrate wideband antenna, filter, and amplifier that were previously designed separately, into a complete UWB receiver front-end. The preferred designs for the integration are antipodal Vivaldi for the antenna, multiple-mode resonator (MMR) for the filter, and three cascaded Agilent HMMC-5200 series-shunt heterojunction bipolar transistor (HBT) amplifiers for the amplifier module. Setup and simulation of the antenna is performed using Agilent ADS Momentum while the simulations of the filter and UWB amplifier module are performed using Agilent ADS Schematic. The antipodal Vivaldi antenna achieves partial wideband capability with return loss below -10 dB between 3.3 GHz and 6.2 GHz. The MMR bandpass filter simulation realizes an almost maximally flat insertion loss response for the entire UWB passband that is from 3.1 GHz to 10.6 GHz and return loss below -15 dB throughout the passband. The UWB amplifier module demonstrates amplification from 28.7 dB to 30.3 dB and return loss below -17 dB from DC to 20 GHz. The front-end simulation realizes 25 dB to 29 dB of signal amplification within the UWB passband. The out-of-band rejection performances are 8.2 dB/GHz and -8.1 dB/GHz roll-off rates for the lower and upper stopband respectively. The link system also realizes low noise figure between 1.47 dB and 3.13 dB within the UWB passband.