In this paper, a low profile and wideband backward-wave directional coupler is introduced. It operates similar to the composite right left handed (CRLH) couplers. Two different mechanisms including connections between the coupled lines to provide shunt inductance for odd mode and defected ground structure (DGS) to add series capacitance for even mode are applied to obtain high performance and wideband coupler. Neural network process is used to obtain the optimized parameters of the proposed coupler. The introduced coupler is then numerically investigated using full wave simulator software. A prototype of the proposed coupler is fabricated and successfully tested. The measured results are in a good agreement with those obtained by simulation. The measured coupling level is 0.49 dB over the frequency range from 6.5 GHz up to 14

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