Compact Hybrid Coaxial Architecture for 3 GHZ-10 GHZ Uwb Quasi-Optical Power Combiners

Abstract

Abstract-Tray-type quasi-optical (QO) power combiners are able to combine the high-and medium-output power of QO systems with the well-known advantages of pulsed ultra-wideband (UWB) systems. In this work, an alternative low-profile tray-type passive structure for 3 GHz-10 GHz power combining is proposed. The purpose of the proposed solution is to reduce the physical size with respect to other existing architectures by using hybrid coaxial lines. In spite of the reduced size, the structure maintains ultra-wideband operation and high combining efficiency, as proved through measurements. Therefore, the proposed structure is suitable for integration with monolithic microwave integrated circuit (MMIC) amplifiers for medium-and high-power generation, depending on the type of MMICs which are integrated into the passive combiner. Numerical analyses of the designed power combiner integrated with some MMIC amplifiers reveal its benefits in terms of increased output power and wider dynamic range compared to isolated MMICs. INTRODUCTIONA rapid diffusion of ultra-wideband (UWB) technologies into the military and civil markets has been observed in recent years. The main reasons can be attributed to the numerous advantages that UWB offers in comparison to narrowband systems. The power Nevertheless, UWB frontends also need sources generating power levels that are able to penetrate high-absorption materials. Single solid-state amplifiers are often unable to provide the power level needed in such applications. Quasi-optical (QO) or spatial power combining systems [7] have shown, in the last two decades, their promising capabilities to produce medium-and high-output power levels for frequencies spanning from the microwave to millimeter-wave ranges. The key concept of a QO combiner is the use of a high-efficient combining network containing several active sources. A QO power combiner consists of a number of solid-state devices, each of them equipped with a transmitting and a receiving antenna. The use of freespace networks for the distribution of the input signal and for the recombination of the amplified contributions permits a strong reduction in terms of losses in comparison to conventional folded combiners. The main reason for this is that the power combining process takes place in the surrounding air.The attention of researchers in the field of QO combiners has been particularly focused on tile-type grid amplifiers [8][9][10], amplifier arrays [11][12][13][14] and oscillators [15,16]. Referring to the tile-type family, represented by grid amplifiers and amplifier arrays (Figure 1(a)), the operating principle is based on the amplification of a free-space wave coming from an external source. A y-polarized incident wave excites RF currents on the receiving antennas of the array/grid, each of which is connected to an amplifier. The amplified versions of those currents are then radiated to the output with 90 • -rotated polarization and the single phase-coherent contributions sum up in the free-space to form a high-power output si...

Printed sectoral horn power combiner

“…Two sub categories can be distinguished: grid-amplifiers (Kim et al, 1993) and arrays of amplifiers (Kawasaki & Itoh, 1993;Russo, Boccia, Amendola, & Di Massa, 2009). In tile configurations, solidstate devices are arranged in waveguides or in coaxial structures (Russo, Boccia, Amendola, & Schumacher, 2012;Song, Fan, & Zhou, 2009), which provides wider bandwidth.…”

Computation of the Resonant Frequency and Quality Factor of Lossy Substrate Integrated Waveguide Resonators by Method of Moments

“…Since its advent, Substrate Integrated Waveguides (SIW) technology has been exploited to realize several passive devices at the frequency of the microwaves and of the millimeter waves. Many examples like filters [1,2], power dividers [3,4], antennas [5,6] and other realizations have been presented in the recent literature. Many of these devices are based on the working principles of resonators.…”

Characterization of Lossy Siw Resonators Based on Multilayer Perceptron Neural Networks on Graphics Processing Unit

“…All kind of devices, operating in the regions of microwaves and millimeter waves, have been developed making SIW a well established technology. Filters [1], antennas [2], power combiners [3,4] and other devices have been successfully designed and realized. The design of such devices can be faced with the help of commercial codes based on finite methods like FEM [5], however, in a series of papers [6][7][8][9] the authors have shown alternative and more effective methods to analyze SIW structures.…”