Experimental study of mutual coupling compensation in smart antennaapplications

摘要

This paper investigates the benefit of mutual couplingncompensation via a method of moments (MoM) approach in a uniformncircular antenna array operating at 1.8 GHz. This mutual couplingncompensation technique is applied to a direction of arrival (DOA) studynof up to two cochannel mobile users. Field measurements and computernsimulations are examined to explore the assumptions of the technique andnverify its effect when using the Bartlett and MUSIC DOA algorithms.nComputer simulations considering the application of the technique tondown-link beamforming are also included. Experimental results show thatnthe mutual coupling compensation technique improves up-link DOAnalgorithm performance primarily by reducing unwanted sidelobe levels.nThis reduction in sidelobe levels aids in down-link beamforming weightndesign. Specifically, simulation results show that use of thencompensation technique allows DOA-based down-link beamforming algorithmsnto perform similarly to spatial signature-based algorithms. All fieldnmeasurements were made using the smart antenna testbed at the Universitynof Texas at Austin