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ABSTRACT The objective of this article is to propose a miniaturized rectangular dielectric resonator antenna (RDRA) configuration and dual mode operation using a simple feeding scheme. It demonstrates the potential advantages achieved by choosing a microstrip line feeding mechanism at the edge of the RDRA. Measurement and simulation results are both in good agreement. The fabricated antenna possesses wide impedance bandwidth (BW) of 800 MHz (5.65 to 6.48 GHz) and dimensions of RDRA are 17 × 7 × 3 mm3. Measured radiation patterns have linear polarization over the frequency range. By the proposed design, the BW is enhanced more than four times as compared to the conventional way to excite the RDRA by microstrip line. To validate the design, the comparison of published design is discussed. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:229-235, 2015. [ABSTRACT FROM AUTHOR]

This work presents a simplified design of a Solid State Power Amplifier (SSPA) with varying RF output power (flexible SSPA) and its' new type of application for onboard application. For satellite applications, the uplink rain fading losses can be compensated with the help of the Automatic Level Control (ALC) technique by increasing the gain of the amplifier but the for downlink rain fading losses the output power of the power amplifier has to be increased. This can be achieved by the use of flexible SSPA to compensate the downlink rain fade losses. For satellite applications it is necessary to maximize power added efficiency in all operating conditions for reliable and cost effective operation. This is achieved by DC bias control of the power stages of the power amplifier to improve the overall power added efficiency. A remarkable improvement of the order of 5 % at 3 dB back off is achieved. As a part of recent developments on flexible payloads worldwide, the flexi TWTAs can be replaced by flexi SSPAs. [ABSTRACT FROM AUTHOR]

In the past, a TEδ01x mode had been proposed with two metal strips on the side walls of a rectangular dielectric resonator antenna (RDRA) as well as hybrid rectangular dielectric-air-metal strips composite resonator antenna. In this paper, a new radiating TEδ10x mode in the RDRA is proposed by placing single metal strip on top surface. To validate the TEδ10x mode and a conventional lowest order TEδ11x mode, simple RDRA with and without a metal strip is designed, fabricated, and measured. The RDRA is mounted on the grounded substrate and fed by a simple microstrip line. Based on parametric study and electric field distributions, dimension along the y-axis is principally used to determine the resonant frequency of the proposed mode. The proposed mode has an impedance bandwidth of 35 MHz at 2.24 GHz and gain of 2.35 dBi. The radiating TEδ10x mode has broadside radiation patterns. As compared to the conventional TEδ11x mode, reduction in the resonant frequency and the impedance bandwidth by 58% and 79% is observed in the new mode. [ABSTRACT FROM AUTHOR]