Performance Comparison of Channel Estimation Algorithms Based on Near-Field Signal Model

As the 5G technology is applied indoors, the antenna array aperture and the distance from the source to the antenna array become comparable, which makes the far-field signal model no longer valid. In this case, the complexity of signal model is increased because the channel parameters are not only the angle of arrival, but also the distance. In this paper, a nearfield signal model based on a uniform circular array (UCA) is studied to avoid the estimation error caused by the plane wave model. Moreover, channel estimation algorithms based on nearfield signal model are investigated and compared in terms of estimation accuracy and algorithm complexity. Finally based on these two aspects, the algorithm that is more suitable for indoor communication will be selected.