Faisal Aldhubaib

Subsurface Target Recognition Based on Transient Electromagnetic Scattering

The E-pulse technique which typically uses transient scattering data from radar targets in free space is one of the most well known resonance based radar target recognition schemes on which target recognition is based. In this communication, the possibility of subsurface target recognition based on the E-pulse technique is investigated using numerical examples of a metallic hip prosthesis embedded in models of realistic human tissue.

A radar target signature based on resonance and dual polarization features

A physically based radar target scattering signature is derived from observable data using a frequency domain scattering model that incorporates the backscattered radar target polarization response at the target natural resonance frequencies (NRF). Two rotationally symmetric targets of simple but similar characteristic geometry are used to demonstrate the theoretical feasibility and the ability to distinguish the two similar targets by this proposed signature.

Characteristic Polarization States Estimation in an Ultrawideband Context: A Frequency Approach

The concept of characteristic polarization states (CPSs) is extended to an ultrawideband (UWB) context. This is achieved by a sparse representation of the target UWB scattering spectrum by a set of frequency bands associated with the target natural resonance modes. The polarization description involves using the average power within each resonant frequency band to derive the Kennaugh power matrix and, subsequently, a set of CPSs using the Lagrangian optimization procedure. To validate this, preliminary feature sets are formed by extracting robust information from each derived CPS and then implementing a correlation measure criterion from which the relationships between these preliminary feature sets as a function of resonance order are established. These relationships are invariant to range and target orientation about the radar-target direction and are robust to noise.

Characteristic Polarization States in an Ultrawideband Context Based on the Singularity Expansion Method

The concept of characteristic polarization states (CPSs) is extended to an ultrawideband (UWB) context by a time-domain approach. This is achieved by a sparse representation of the target UWB temporal response by the singularity expansion model. The polarization description uses the complex residues and frequencies associated with each singularity mode to derive both coherent target polarization scattering information and, subsequently (using the Lagrangian optimization procedure), a set of CPSs associated with the singularities of interest.

Optimal radar bistatic angle by statistical analysis of scattering patterns

In this work, we introduce the concept of optimal bistatic angle such that the scattered radar target signal has a robust strength level irrespective of the target aspect. The concept involves statistically analyzing the scattering patterns as a function of the target aspect to a fixed and known incident radar direction. Henceforth, statistical quantities like mean and standard deviation are used to obtain statistics patterns for radar scattering patterns of an ellipsoid, a cylinder, and a square shape targets. Since different targets are likely to have different optimal angles, we propose using the optimal angle concept to improve the signal-to-noise ratio of a target of interest. This benefit can be further exploited in a radar target classification process.

Ultra wideband radar target recognition using multiple transient responses

In resonance based target recognition, studies have mainly been focus on exploiting the natural resonant modes embedded in an ultra wideband transient signature measured at a specific aspect and polarization state. The information that carries in polarimetric and aspect dependency nature of the scattering phenomena has not been well exploited. The objective of this paper is to investigate the pros and cons for different possible approaches to handle the multiple aspects, full polarimetric, and wideband scattered data, aiming for a more robust target recognition procedures and outcomes.

Polarization studies in the UWB radar target response using joint Time-Frequency analysis

The polarization dependent nature of ultra wideband (UWB) scattering from a radar target is studied using time-frequency (TF) analysis. The UWB frequency responses of the target under linear and circular polarization incidence are studied. The results demonstrate that the Q-factor of the resonant peaks vary as the incident polarization changes, indicating that different layer SEM poles are extracted for different polarization incident states.