Wideband mutual coupling compensation based on MIMO system identification

A wideband mutual coupling compensation method is introduced in this paper. Using the method of system identification in the frequency domain, a multi-input and multi-output (MIMO) compensation network is identified to equalize the frequency-dependent characteristics of array mutual coupling effect. The receiving mutual impedances calculated at discrete sampling frequencies over a wide bandwidth are used as input data for the system identification. The least-square method is applied to identify the wideband mutual coupling compensation network. The decoupled array snapshots are applied to a wideband direction of arrival (DOA) estimation example using a compact uniform circular array. The almost frequency-independent estimation results indicate the effectiveness and validity of the proposed method for wideband mutual coupling compensation.