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In this paper a multi target Doppler-only tracking scheme as well as its related algorithms are proposed and analyzed. Specifically the Doppler-only single target localization is firstly addressed in an heteroscedastic environment exploiting a weighted least square approach. Then this approach is extended to a multi target case introducing an algorithm to solve the inherent measurements to targets...
We deal with the performance prediction of the conventional cell-averaging constant false alarm rate (CA-CFAR) detector in the presence of non-independent identically distributed (non-iid) target backscattered echoes. Accounting for the generalized Swerling-Chi fluctuation target model, we develop the analytical expressions for the target detection probability for CA-CFAR detector. Finally, we assess...
Some Inverse Synthetic Aperture Radar (ISAR) algorithms form the image in a two-step process of range alignment and phase conjugation. This paper discusses a comprehensive set of measures used to quantify the quality of range alignment, with the aim of 1) reviewing their benefits and shortcomings and 2) comparing their relative performance. Some quality measures may favour particular alignment techniques...
This paper describes a new STAP algorithm based on Principal Components (PC) method. PC performs an eigendecomposition of the full space-time covariance matrix retaining the dominant (those associated with the interference space) eigenvalues and eigenvectors pairs to build the STAP filter coefficients. In this new proposed algorithm PC method is applied on the space-time covariance matrix associated...
The paper presents the instrument concept and performance of a Ka-band single-pass interferemetric mission proposed for measuring topography and topographic changes. A formation flying constellation of two compact synthetic aperture radars (SAR) satellites equipped with innovative digital beamforming hardware and advanced operation modes is described.
This paper proposes a solution to the problem of searching for a moving airborne target in unknown coloured Gaussian interference. Traditional space-time adaptive processing (STAP) approaches to this problem rely on the existence of a training data set that helps build an estimate to the covariance matrix of the background noise and interference. These algorithms are thus labelled as two data set...
Radar target classification typically uses feature sets derived from high range resolution profiles as an input to a classifier. However, such feature sets, when projected in feature space, show both substantial overlap for different targets and substantial variability for a single target. This results in degraded classification performance, as targets cannot be reliably distinguished from one another...
This paper presents a systematic methodology that rates the effectiveness of each tracker configuration or signal processing algorithm in a radar system. The approach uses a linear additive model for aggregating selected Measures of Performance (MOP) with the relative importance of each MOP determined through the application of the analytic hierarchy process (AHP). With the aggregate MOP score, track...
This paper presents a novel processing method of TerraSAR-X spotlight data to high accuracy Digital Elevation Model generation, since many conventional SAR interferometry processing methods do not work well for TerraSAR-X spotlight data interferometry processing. The proposed method is based on co-registration with Doppler centroid frequency estimation and joint phase unwrapping method, and it had...
Many modern radar systems employ pulse compression to maximize the energy on target while maintaining high range resolution. For a solitary point target in white noise, employing a matched filter on receive will maximize the target signal-to-noise ratio (SNR) at the output of the receiver. The matched filter itself is a time-reversed version of the transmitted waveform which is convolved with the...
In Digital Beamforming (DBF) radars, multiple beams are formed simultaneously at different azimuth and/or elevation angles to monitor large areas of interest. In order to estimate the location of a target in azimuth without specifically steering the beams at the target or using special techniques such as monopulse, amplitude comparison angle measurement can be used. Since the digital phased array...
In this paper a receiver architecture for a Passive Bistatic Radar (PBR) based on multiple broadcast signals is described. Specific receiver sections are foreseen for each selected waveform of opportunity, while a common part of the system performs the I&Q demodulation and the Analog-to-Digital conversion. The scheme for a double conversion (up-conversion stage from Radio Frequency to Intermediate...
The goal of this paper is to develop methods for determining the calibrated array weights for uniform linear transmit and receive radar arrays necessary to achieve desired uniform sidelobe performance. The ability of current radar systems to suppress sidelobe clutter and interference is seriously limited by miscalibration of antenna array gain and phase due to non-ideal antenna and near-field scattering...
Phase shifters distort a wideband signal as well as cause beam squint in a large array. Time delay units are expensive, so they are used sparingly. This paper explains the performance tradeoffs associated with the selection, size, and distribution of time delay units in a large wideband phased array antenna. Design equations and examples are given.
Wind Energy is considered as the green and free energy. It can be harvested any time wherever there are high winds. One of the concerns with turbine is with birds and bats. There are reports of birds and bats fatalities around wind turbine. One way to investigate this issue is to monitor wind turbine areas. Researchers have used marine radars for this purpose. Weather radars commonly known as NEXRAD...
In this paper, we present an approach to the design of orthogonal, Doppler tolerant waveforms for diversity waveform radar (e.g. MIMO radar). Previous work has given little consideration to the design of radar waveforms that remain orthogonal when they are received. Our research is focused on: (1) developing sets of waveforms that are orthogonal on both transmit and receive, and (2) ensuring that...
Change detection by spaceborne high resolution synthetic aperture radar (SAR) images is a very powerful tool for reconnaissance tasks, as this is largely uninfluenced by weather conditions or the time of the day and additionally doesn't violate sovereign rights. The use of different spaceborne SAR sensors would reduce the revisit time of a region of interest considerably, allowing a denser monitoring...
Passive radars utilize a source of illumination that is primarily intended for other use. The DVB-T2 is a digital television broadcast system that can be used as an illuminator in passive radar configurations. The design of the passive radar systems is especially challenging since there is no control over the transmitted waveforms. In this paper, we propose a method for control symbol based passive...
The unique, bi-pedal motion of humans has been shown to generate a characteristic micro-Doppler signature in the time-frequency domain that can be used to discriminate humans from not just other targets, but also between different activities, such as walking and running. However, the classification performance increasingly drops as the aspect angle between the target and radar approaches perpendicular,...
We address the problem of three-dimensional (3-D) imaging for multiple-input multiple-output (MIMO) radar in the presence of phase synchronization mismatch between each transmitter-receiver pair. Although usually set to the default values (zero) in the popular practice, such inevitable errors often occur owing to imperfect knowledge of the local oscillators and could seriously deteriorate the imaging...
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