Design and Implementation of Radio Frequency Power Feeding Networks for Antenna Array Applications: Simulation and Measurements of Multiport, Equal and Unequal, Fixed and Reconfigurable Radio Frequency Power Feeding Networks for Narrow and Ultra-Wideband Applications
AuthorAli, Ammar H.A.
SupervisorAbd-Alhameed, Raed A.
KeywordWilkinson power divider
Uniplanar power divider
Multi-layer power divider
Multi-port power divider
Ultra-wideband power divider
Reconfigurable power divider
Equal and unequal power divider
The University of Bradford theses are licenced under a Creative Commons Licence.
InstitutionUniversity of Bradford
DepartmentFaculty of Engineering and Informatics
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AbstractPower dividers are vital components and widely used in radio technology, such as antenna arrays, power amplifiers, multiplexers and mixers. A good example is the well-known Wilkinson power divider with its distinctive feeding network characteristics. A comprehensive review indicated that limited research is carried out in the area of planar multiport and reconfigurable power dividers in terms of the power levels between output ports. The main objectives of this work were to develop a small size power divider, a planer multi-output ports power divider and a power divider with a reconfigurable power division ratio. These power dividers were designed to operate over either an ultra-wideband frequency (3.1-10.6 GHz) or WLAN bands (2.4 or 5.2 GHz). A novel multi-layered topology solved the complexity of interconnecting isolation resistors by introducing an additional layer below the ground layer. The prototype was fabricated and tested to validate the results. The measurements and simulation were in good agreement. Finally, a novel uniplanar power divider with reconfigurable output power level difference was developed. The configurability feature was achieved by tuning the quarter wave transformer using one varactor diode. The power divider was applied to improve a full duplex system cancellation performance at the receiver element caused by interference from in-site transmitting antennas. This study investigated fixed power dividers, multi-output power dividers and reconfigurable power dividers. The measurements validated by the simulation results and applications proved the designed power dividers could be used in practical applications.
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A design procedure for a 1-to-4 Ultra-Wideband Wilkinson power dividerAli, Ammar H.; Abd-Alhameed, Raed A.; Hu, Yim Fun; Child, Mark B. (2016-11)The design of a physically small, equal phase and equal power, 1-to-4 ultra-wideband Wilkinson power divider is presented. Initially, a 1-to-2 divider was designed and optimized for the 3.1 GHz-to-10.6 GHz range. The 1-to-4 divider was then realized using three 1-to-2 dividers, and further optimized for full band insertion loss, return loss, and isolation. The circuits were constructed using a 0.75 mm thick Rogers RO3035 substrate, and experimentally validated.
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