Capabilities of Dual-Frequency Millimeter Wave SAR With Monopulse Processing for Ground Moving Target Indication

Abstract

Ground moving target indication (GMTI) for syn-thetic aperture radar (SAR) provides information on nonstatic objects in radar imagery of a static ground scene. An efficient approach for GMTI is the use of multichannel SAR systems for a space-and time-variant analysis of moving targets. This allows the indication, correction of position displacement, and estimation of radial velocity components of moving targets in a SAR image. All three steps are possible due to a determinable Doppler frequency shift in the radar signal caused by radial target movement. This paper focuses on the millimeter wave (mmW) SAR system MEMPHIS with multichannel amplitude-comparison monopulse data acquisition and the ability to use carrier frequencies of 35 and 94 GHz simultaneously, making it a dual-frequency SAR. This paper includes mmW-specific SAR GMTI considerations, an adaptive algorithm to collect velocity and position information on moving targets with mmW monopulse radar, and a discussion on GMTI blind speed elimination and target velocity ambiguity resolving by dual-frequency SAR. To determine the capabilities of both, system and algorithm, three large-scale experiments with MEMPHIS in different environments are presented. Abstract-Ground moving target indication (GMTI) for synthetic aperture radar (SAR) provides information on nonstatic objects in radar imagery of a static ground scene. An efficient approach for GMTI is the use of multichannel SAR systems for a space-and time-variant analysis of moving targets. This allows the indication, correction of position displacement, and estimation of radial velocity components of moving targets in a SAR image. All three steps are possible due to a determinable Doppler frequency shift in the radar signal caused by radial target movement. This paper focuses on the millimeter wave (mmW) SAR system MEMPHIS with multichannel amplitude-comparison monopulse data acquisition and the ability to use carrier frequencies of 35 and 94 GHz simultaneously, making it a dual-frequency SAR. This paper includes mmW-specific SAR GMTI considerations, an adaptive algorithm to collect velocity and position information on moving targets with mmW monopulse radar, and a discussion on GMTI blind speed elimination and target velocity ambiguity resolving by dual-frequency SAR. To determine the capabilities of both, system and algorithm, three large-scale experiments with MEMPHIS in different environments are presented.Index Terms-Ground moving target indication (GMTI), millimeter wave (mmW) radar, monopulse radar, synthetic aperture radar (SAR).

A Closed-Form Robust Chinese Remainder Theorem and Its Performance Analysis

“…With these erroneous remainders, (5) becomes (11) If the remainder errors are constrained as (12) then and can be accurately reconstructed by (8). Therefore, the unknown can be estimated as (13) where is the average of the remainders errors, and stands for the rounding integer, i.e., for any is an integer and subject to (14) In fact,…”

“…Recall that stands for the rounding integer which is defined in (14). Let for denote a set of solution of (21) Although the condition (28) in Theorem 1 is necessary and sufficient (under the assumption of (27)) for the uniqueness of the solution of the folding integers from our proposed closedform robust CRT, it involves with two remainder errors and hard to check in practice.…”

Ground moving target indication and parameters estimation using a dual-frequency synthetic aperture radar

“…This equation is an extension to [25,26] and is the basic model for correcting the target's real azimuth position in a SAR image.…”

Moving-Target Velocity Estimation in a Complex-Valued Sar Imagery

“…Due to temporal sampling, the induced Doppler shift suffers the limitation of pulse repetition frequency (PRF). Classical solutions to this problem are to relocate the equipment with an increasing PRF [2] or a nonuniform PRF [26], or using waveform diversity techniques [27]. However, these measures increase the memory requirement and equipment complexity.…”