Research Of DOA Estimation Algorithms With Known Waveforms

As an important research content of array signal processing,the direction of arrival(DOA)estimation has been rapidly developed in recent years.It not only has a wide range of applications in the field of military,but also plays a more crucial role in many civilian aspects.The traditional DOA estimation technique uses array space sampling without considering any prior information of the received signal.However,In radar,sonar,medical equipment and other applications,the waveform of the signal is often completely known or partly known,using the prior knowledge of known waveforms can further improve DOA estimation accuracy and reduce computational complexity.Therefore,the direction of arrival estimation based on the known waveform is the main research content of this paper.This paper mainly studies the maximum likelihood class and iterative class method.The main content of this article is as follows:The decoupled maximum likelihood estimation algorithm,the decoupled maximum likelihood estimation algorithm with coherent signals and the maximum likelihood estimation algorithm with coherent signals in white noise are studied,the above method has been improved with the alternating maximum algorithm.Joint the Angle and Fading Coefficients Estimation Algorithm is also studied.The subarray beamforming algorithm is studied,and the multistage Wiener filter is introduced into the algorithm.The CSA-SBDOA algorithm based on known waveforms is proposed.This method avoids the process of inverting the matrix and does not calculate the blocking matrix.The subspace decomposition algorithm is improved by using the known waveform information to avoid the process of feature decomposition.When the incoming signals are coherent,The spatial smoothing algorithm is directly used in the data domain.The wideband RELAX algorithm with known waveform is studied.The received data of the reference array element can be represented by the integral of the waveform frequency domain.Considering the delay of each array element,a new wideband array receiving model can be obtained.Combined with the RELAX algorithm based on signal separation,the estimate of the angle of arrival can be obtained.The algorithm does not require narrow-band preprocessing,and it has the advantage of easy calculation.