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A QO power divider were fabricated practically and the S-parameter was measured at 37.5GHz using a Millimeter wave vector network analyzer (37369C, Anritsu). The measured transmission coefficients between all output ports and input port are shown in Figure 11. The insertion loss variation of different output ports was less than 62.1 dB and the relative phase variation less than 9. Total output power was achieved by adding up the power of all out ports to be 80.8% of the input power at the designed working frequency, which is well agreed with the simulated value of 88.7%. CONCLUSIONSA general method of designing QO power divider was proposed in this article. And applying this method, a 1 Â 18 QO power divider was designed successfully. The measured results of the divider were consistent with that of simulation, and the ratio of the total output power to the input power was 80.8%. So feasibility of holography QO power-combining was verified and validity of method of designing was also confirmed by the experiment.Divider to split input power into further more outputs directly can be designed using this method. And this method can be used to solve the heat-sinking problem at higher frequencies even at submillimeter wave band because of no degradation of dividing efficiency resulted by enlarging spacing between neighbor output ports. ACKNOWLEDGMENTSThe authors will thank to Southwest Institute of Electronic Technology for financial support of this research. ABSTRACT: An on-board uniplanar printed mobile handset antenna with a small size of 15 Â 30 mm 2 for 8-band long term evolution/wireless wide area network (LTE/WWAN) (698-960/1710-2690 MHz) operation is presented. The antenna is a spiral monopole coupled with a long parasitic shorted strip. The spiral monopole has a length of 78 mm (about 0.25 wavelength at 950 MHz), while the shorted strip capacitively excited by the spiral monopole has a length of 125 mm (close to 0.25 wavelength at 700 MHz). The spiral monopole is encircled by the shorted strip so that the antenna has a compact configuration to fit in a small no-ground portion at the corner of the bottom edge of the main circuit board in the mobile handset. In addition, the antenna is closely integrated with the system ground plane on the main circuit board and is spaced by a small distance of 0.5 mm to the nearby system ground plane. This leads to compact integration of the on-board LTE/WWAN printed antenna on the main circuit board of the mobile handset. Results of the proposed antenna including its specific absorption rate and hearing aid compatibility behavior are presented and discussed. The antenna is about the smallest for the on-board all-printing LTE/WWAN handset antennas that have been reported for the present. [20,21] or the lens of the embedded digital camera [22][23][24] on the main circuit board and limits the compact integration of the LTE/WWAN antenna inside the mobile handset.In this article, we present an on-board printed internal mobile handset antenna for eight-band LTE/WWAN operation with ...

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This paper presents a broad-band spatial powercombining system based on tapered-slot antenna arrays integrated in a standard WR-90 waveguide environment. The system is designed using a modular tray architecture, providing full waveguide-band frequency coverage and an excellent thermal environment for a set of monolithic-microwave integrated-circuit (MMIC) amplifiers. The shape of the tapered-slot or finline structures was optimized to minimize return loss and provide a broad-band impedance transformation from the waveguide mode to the MMIC amplifiers. A prototype eight-element array using commercial GaAs MMIC power amplifiers yielded a maximum of 41-W output power (continuous wave) with a gain variation less than 61.2 dB within the entire band of interest. The average combining efficiency over the operating band was estimated at 73%. The results suggest the efficacy of the design and a strong potential for higher powers by moving toward a greater number of MMIC's per tray and a larger number of trays. Should the 100-W system be realized in the near future, our combiner system will become a promising candidate to challenge the dominant position currently claimed by the traveling-wave tube amplifiers.

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