All-microstrip design of three multiplexed antennas and LNA for UWB systems

An ultra-wideband (UWB) 3.1–4.8 GHz radio front-end consisting of three frequency multiplexed antennas and a low-noise amplifier (LNA) is presented in this paper. Using one antenna for each sub-band and an LNA designed for maximum-flat power gain provides equal performance within the entire frequency band. Frequency multiplexing is used to combine the antennas for multi-band UWB. The LNA is optimized for wideband operation and minimum noise figure. The LNA design employs dual-section input and output matching networks. The antennas, the frequency multiplexing network, the matching networks and the bias circuit of the LNA are all implemented using microstrip lines.