CAJ | 학술논문

低旁瓣MIMO雷达发射方向图可以在保证主瓣发射能量的前提下，抑制旁瓣杂波和虚假目标能量，从而达到提升回波信噪比的目的。该文提出一种低旁瓣MIMO雷达发射方向图设计方法，通过对已有发射信号协方差矩阵的非对角线元素进行修正来实现低旁瓣方向图的优化设计。首先，利用方向图匹配设计方法得到具有期望主瓣形状的发射方向图，并以其作为初始值；其次，以最小化峰值旁瓣或积分旁瓣为目标函数，在约束修正后的信号协方差矩阵为半正定矩阵的前提下，利用修正矩阵的Frobenius范数为量度约束主瓣形状失真程度。上述两个优化问题都是凸优化问题，可以求得全局最优解。仿真结果表明，该方法可以得到具有期望主瓣形状和低旁瓣特性的方向图。
저방판MIMO뢰체발사방향도가이재보증주판발사능량적전제하，억제방판잡파화허가목표능량，종이체도제승회파신조비적목적。해문제출일충저방판MIMO뢰체발사방향도설계방법，통과대이유발사신호협방차구진적비대각선원소진행수정래실현저방판방향도적우화설계。수선，이용방향도필배설계방법득도구유기망주판형상적발사방향도，병이기작위초시치；기차，이최소화봉치방판혹적분방판위목표함수，재약속수정후적신호협방차구진위반정정구진적전제하，이용수정구진적Frobenius범수위량도약속주판형상실진정도。상술량개우화문제도시철우화문제，가이구득전국최우해。방진결과표명，해방법가이득도구유기망주판형상화저방판특성적방향도。
Low sidelobe transmit pattern of MIMO radar can concentrate majority energy in the mainlobe region to improve the target detection, and reduce the energy of clutter and false targets from sidelobe, so as to enhance the SNR of echo. Based on a modified non-diagonal elements of transmit signal covariance matrix, a low sidelobe transmit pattern optimization algorithm for MIMO radar is proposed. Firstly, the pattern matching design method is implemented to obtain the desired mainlobe shape of transmit pattern, with the results as the initial value. Secondly, the cost function can be formulated as the minimization of peak-sidelobe or integrated-sideloble; the mainlobe shape distortion can be constrained by the Frobenius norm of modification matrix, and the modified transmit signal covariance matrix needs to be positive semi-definite. Since the two optimization problems are convex, the global optima can be acquired. The simulation results show that the desired mainlobe shape and low sidelobe pattern can be obtaibed with the proposed method.