DOA Estimation of a Wideband Signal Using a 2-D Array Antenna with Spatial Processing Capability

This paper describes investigations into Direction–Of–Arrival (DOA) estimation of a wideband signal by a two–dimensional array antenna, which employs only spatial signal processing for beam forming. The elements of this array are arranged in a horizontal rectangular lattice to steer a beam in azimuth over a wide frequency band. By applying the concept of interpolated array, a composite covariance matrix is produced. This composite covariance matrix is a simple addition of covariance matrices of narrowband virtual arrays, being stretched or compressed versions of a nominal array, all featuring the same radiation pattern. DOA is estimated by eigen–decomposition of the composite covariance matrix using the narrowband MUSIC algorithm. The performance of the proposed DOA estimation method is demonstrated by computer simulations. The obtained results indicate that the two–dimensional array provides better estimation of DOA than the one–dimensional one when the interpolated array technique in conjunction with the MUSIC algorithm is applie

Comparisons of Performance of Various Transmission Schemes of MIMO System Operating under Rician Channel Conditions

In this paper, we compare various transmission schemes, as described by the covariance matrix of transmitted signals, for a Multiple Input Multiple Output (MIMO) system operating under Rician channel conditions. It is shown that in order to obtain the best performance in terms of the maximum communication rate the receiver has to have full knowledge of the channel while the transmitter requires the knowledge of the Rice factor and the signal to noise ratio that are measured at the receiver. Based on this, a new transmission scheme is described. Analytical and simulation results are presented showing that the proposed transmission scheme outperforms the other schemes, which were reported earlier in the literature

Mutual coupling in antenna arrays

10.1155/2010/736701International Journal of Antennas and Propagation2010