0.5–20-GHz UWB Distributed Combiners and Dividers for Multi-Antenna Transceivers

This paper presents discrete active combiners and dividers for ultra-wideband (UWB) applications. The proposed solution exploits distributed amplifier techniques to perform the combination and division of signals over the band from 0.5 to 20 GHz. Three circuit boards are demonstrated: a 2-to-1 active combiner with 17-dB gain, a 4-to-1 active combiner with 30-dB gain, and a 2-to-1 active divider with 10-dB gain. Standard S-parameter and large-signal measurements have been performed to characterize the presented circuit. Multi-antenna demonstrators have been setup to validate the device functionality in more complex scenarios. In particular combination of wideband and narrowband communications has been demonstrated, as well as the use of the combiners for UWB antenna arrays. The presented 4-to-1 combiner shows the best values in terms of gain and a number of inputs with respect to the state-of-art (SOA), while the performance of the other presented devices is comparable to the SOA despite using SMA connectors in place of on-chip measurements.