IEEE Microwave and Wireless Components Letters · 2014 · 20 citations · 10 references
EngineeringElectrical EngineeringAntennasMicrowave EngineeringWireless CommunicationsMicrowave AntennasMicrowave Integrated CircuitsMicrowave Network AnalysisMicrowave System DesignPlanar AntennasUltra-wideband CommunicationCompact Coupler DesignImbalanceMicrowave Coupler DesignMultilayer CouplersReturn LossScattering Matrix AnalysisWideband Couplers
We present a multilayer 4 × 4 Butler matrix based on corrugated slot-coupled structures, which operates over the complete UWB band (3.1 to 10.6 GHz) with excellent phase and amplitude performance. A prototype has been fabricated which covers the UWB band with a measured return loss better than 21 dB, an isolation better than 24 dB, an amplitude imbalance lower than 1.2 dB and a maximum differential phase error of ±4.5°.
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