Research Of DOA Estimation Algorithm Of Wideband Array Signals

Array structure is widely used in radar, communication, electronics, biomedical and many other areas. Direction of Arrival (DOA for short) is a very important content of the research of Array Signal Processing. Wideband signal or even ultra-wideband signal is widely used in the array system at present, however, traditional algorithms are only limited to narrowband signal processing. Therefore, the research of DOA estimation of Array Signal Processing based on wideband system gets more and more attention. This paper focuses on the study of DOA estimation algorithms of broadband system. The main works of this paper are as follows:1. Array model of narrowband system and array model of wideband system are built under ideal condition and array manifolds of each common array lattice structure are studied. Also, two classical algorithms are discussed:MUSIC and ESPRIT. Furthermore, simulation shows that MUSIC algorithms can deal with coherent signals when data covariance matrix has been conjugate rearrangement.2. Two wideband DOA estimation algorithms based on subspace method are analyzed and:the Incoherent Signal subspace Method (ISM) and the Coherent Signal subspace Method (CSM). ISM and modified ISM are discussed and the results of them are compared through computer simulations and so as well as CSM which uses TCT algorithm.3. The DOA estimation algorithm based on the true time delay (TTD) theory is discussed. This method uses TTD theory to eliminate the wave path difference between array elements and the phases are synchronized and the signals are pulse compressed to get the result of DOA. The simulation points out that this method can figure out the DOA result of any input waveform without knowing the number of the signal source.