Closed-Form Waveform Design for MIMO Radar Transmit Beampattern Synthesis via Integral Equality

Yezi Ma,Yan Pan,Huaguo Zhang,Ping Wei

doi:10.1109/access.2020.2996676

Abstract

Recently, due to the adequate use of waveform diversity, MIMO technology has been widely adopted, resulting in the waveform design for MIMO radar beampattern synthesis becoming a hot issue. However, most previous works regarding this problem optimize the waveform by introducing the global mean squared error (MSE) as the cost function, this requires large computation in applications. Different from these works, we adopt the idea from the shaped beampattern synthesis problem of 2-D array in this paper, that is, to form a flat-top beampattern in the desired area with small ripple. By considering the physical meaning of the flat-top beampattern from scratch, the MIMO waveform design problem is turned to designing the waveforms that make its beampattern integral (i.e. the energy transmitted by array) equal in the desired area. Subsequently, we put forth a closed-form method and give its mathematical proof. Numerical simulations and comparisons to known MIMO radar waveform design methods are provided to verify its effectiveness and outperformance.

Highlights

In the past decade, multiple-input multiple-output (MIMO) technology has attracted widespread attention and been widely used in the fields of communication [1], [2], beamforming technique [3], [4], source localization [5]–[7] and target tracking [8]
Different from the previous work designing S by optimizing global mean squared error (MSE), in this paper, as shown in the FIGURE 2, we introduce the ‘distance’ ε between the desired beampattern shaped d (θ ) and the MIMO radar transmit beampattern F (θ ) from the shaped beampattern synthesis problem [30]
Unlike previous work optimizing the waveform by introducing the global MSE as the cost function, we use the idea from shaped beampattern synthesis problem of 2-D array, which synthesis the beampattern with the smallest local MSE in the desired area

Summary

INTRODUCTION

Multiple-input multiple-output (MIMO) technology has attracted widespread attention and been widely used in the fields of communication [1], [2], beamforming technique [3], [4], source localization [5]–[7] and target tracking [8]. Y. Ma et al.: Closed-Form Waveform Design for MIMO Radar Transmit Beampattern Synthesis via Integral Equality waveform covariance matrix R that matches the desired beampattern [27], [28]. In the problem of shaped beampattern synthesis with time-invariant parameters, accurately transmitting the array energy to certain desired areas means forming flat-top beampatterns with smallest local MSE in the desired areas [30], [31]. This problem usually requires lots of optimizations as well [32]–[35]. Notation: We use uppercase (lowercase) bold-face letters to denote matrices (column vectors). (·)T and (·)H represent the transpose and conjugate transpose, respectively. sup (·) denotes the supremum

BEAMPATTERN SYNTHESIS PROBLEM FOR MIMO RADAR

SIMULATIONS

ONE MAINLOBE BEAM

Findings

CONCLUSION