Study On Approaches Of MIMO Radar Array Design

MIMO radar is a new system that has been payed a lot of attention by both domestic and international researchers ever since its proposal. At the same time, the research topics of traditional array radar systems such as array design are endued with novel connotations under this new concept. Based on the well-developed theories of traditional array design, many researchers have worked on MIMO radar array design and obtained some important results. In the context that MIMO radar system is flourishing very fast, this dissertation also studies on the hot issue of MIMO radar array design subject and put forward several approaches, among which some are inspired by the ideas and theories of traditional array design. The specific studies are as follows:Chapter one introduces the basic concepts of MIMO radar, reviews the MIMO radar development process and current status, and then summerizes the published results and main research contents of MIMO radar array design.Chapter two specifically discusses MIMO radar system structure, basic principles and main features, and re-establishes the signal model. On this basis, MIMO radar matched filtering and beamforming processing structure is studied and the beam pattern formula is derived. In addition, the concept of virtual array is detailedly introduced and its formation principle is explained by bringing in spatial convolution theory.Chapter three mainly studies on MIMO radar array design problem from the perspective of pattern optimization. On the one hand, taking into account that traditional methods only optimize side lobe amplitude while ignoring main lobe performances, a new objective function which contains both beam width and side lobe level is proposed, so that the obtained array can reach a compromise between them. On the other hand, a new array design approach using pattern fitting is also proposed. This method treats the error integrality of the actual array pattern and desired pattern as an objective function to fit the optimized array pattern to the desired pattern, so as to achieve optimization purpose.Chapter four focuses on array design of MIMO radar by exploying polynomial theory. The part of article firstly builds the equivalent relationships between sparse array and polynomial, polynomial multiplication and spatial convolution of transmiting array and receiving array, thus polynomial theories can be utilized for radar array design. According to the requirement of uniform virtual array, a method is given to achieve this purpose by using factorization theory. Moreover, the tapering aperture function in traditional array is refered in order to improve beam pattern performances.Finally, chapter five summarizes the works in this article and outlines the future research directions of MIMO radar array design.