This article presents a S-C band active balun in a GaN integrated technology. Based on a differential pair this circuit realizes the single to differential conversion. Moreover this circuit can be used as preamplifier to drive a power stage. It delivers more than 25dBm in each differential path in the [2,4GHz-6GHz] band with a maximum of 29dBm at 3.8GHz. The chip has been realized in the UMS GH25 process, a GaN HEMT technology with a 0.25µm gate length. I.

This article presents a 4-6GHz power amplifier in a 0.25µm GaN integrated technology from UMS foundry. Two unit power cells are combined to increase output power. A new power combiner based on a stacked balun is presented. It has the advantage of occupying a much smaller area than a conventional one. The measured circuit exhibits a peak output power of 37 dBm together with a peak PAE of 47% at 4GHz. Index Terms-GaN. High power amplifier (HPA), power combining, vertically stacked balun.

This article reports the design of a switchable low‐noise power amplifier (LNPA) intended for an active backscatter tag used in microwave localization and positioning applications. Due to system specifications, the backscattering transponder requires an amplifier having both low‐noise and high‐output power characteristics at the same time. Low‐noise amplifier and PA design considerations are both taken into account to realize a single structure achieving the required performances. The proposed LNPA is operating in the frequency range of 4.5–5.8 GHz. It achieves a gain of 21 dB with a ripple of ±1 dB, a noise figure of less than 2.5 dB, and an output compression point at −1 dB of 11 dBm over the operational bandwidth. This structure can be switched on and off by a control signal to modulate the tag radar cross section and enable distance measurement. A packaged prototype of the LNPA was fabricated and measured. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1251–1255, 2014