X‐band high‐power amplifier with a magnetically coupled power‐combiner

Abstract

In this article, a high-power amplifier for X-band application is studied, which consists of a two-stage amplifier with magnetically coupled power-combiners and dividers. These are based on transmission line transformers, which has lower loss characteristics than spiral-type transformers at the frequencies. The proposed amplifier utilizes the voltage-combining concept with the transformers and differential amplifiers. The size of the amplifier is also minimized by using the virtual grounds of the differential structure. The saturated output power of the power amplifier is 38.1 dBm (6.45 W), and the gain is 17 dB at 10 GHz. The area of the chip is 2.56 mm  3.13 mm and the power density of the amplifier is 806 mW/mm 2 .ABSTRACT: This article presents the design and radiation characteristics of a dual-mode corrugated matched feed horn. This type of feed eliminates the unwanted high cross-polarization of an offset parabolic reflector antenna and improves the overall performance of the antenna sub-system. In a cylindrical corrugated structure, higher order HE 21 mode is added with the fundamental HE 11 mode to configure a dual-mode corrugated horn. For the proposed horn, the return-loss characteristics and the far-field radiation patterns were measured and the results are compared with the simulated results. The horn has been used as a primary feed device to illuminate a linearly polarized offset parabolic reflector antenna and the improvement in the crosspolarization has been estimated. Figure 1 Simulated secondary radiation pattern of an offset reflector illuminated by a conventional (HE 11 mode guided) corrugated horn. (For F/D ¼ 0.82, h 0 ¼ 34.8 )

An X‐band CMOS power amplifier with a driver stage using a shot‐through current rejection technique

“…Power amplifiers have many uses owing to their essential functions for wireless communication systems . In particular, along with the requirement of low‐cost implementation, power amplifiers that use CMOS technology have become more popular .…”