In this work a new robust adaptive digital beamforming algorithm called Gaussian Robust Capon Beamformer (GRCB) is proposed, it is based on conventional Capon criteria and provides compensation of the steering vector errors through diagonal loading approach. This research was conducted assuming a critical scenario where a communication environment presents a high value of angular spread (AS >2 degrees) on signal of interest and in which other beamforming methods, including robust Capon algorithm, can degrade their performance upon presenting the phenomenon of auto-cancellation of the signal of interest. Additionally, is discussed a study of the beamforming algorithms performance, based on Minimum Variance Distortionless Response (MVDR) method as well as its robust version; this study is conducted using a radio channel model with a Gaussian scatters distribution, around the signal of interest and typical angular spread values for different mobile communication environments. Finally, simulations results are shown where the performance of GRCB algorithm is compared with different approaches of Capon beamforming, can be observe that using the proposed algorithm is possible to achieve a minimization in signal of interest degradation and a better isolation, regardless of interferers and noise levels.
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