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Due to the associated computational load and required statistically homogeneous training, fully optimal space-time adaptive processing (STAP) is well-accepted to be impractical. Previous work has addressed these issues by reducing the adaptive degrees of freedom (DoF). In this paper we introduce a new multistage STAP approach that significantly reduces required sample support, and computational complexity,...
High Frequency Surface Wave Radar (HFSWR) is a technology used for over-the-horizon detection of ocean vessels. This radar exploits the diffraction of electromagnetic waves around the curved surface of the Earth. To minimize the attenuation of the diffracted waves, the radar must operate at frequencies in the lower part of the high frequency (HF) band. However, radar signals at these frequencies also...
The use of Frank waveform codes in radar applications is well known. These codes are phase modulation based, with the number of phase steps dependent on the order of the code. Amplitude shaping techniques are applied to the modulation bits to reduce the sidelobe levels and constrain the bandwidth of the transmitted signal. This combination of amplitude shaping and phase modulation of the waveform...
This paper investigates the use of space-time adaptive processing (STAP) for high frequency surface wave radar (HFSWR) systems. STAP has hitherto been investigated in great detail for airborne radar systems; the majority of the adaptive algorithms that have been developed have been designed with a bias towards such applications. HFSWR systems are characterized by the severely limited number of data...
A high frequency (HF) radar system comprising a skywave transmit channel and surface wave receive channel is studied. Simple analytic expressions for the resolution of this radar system are determined by considering the spreading of radar signals in Doppler and angle during the ionospheric propagation. The detection of ocean surface targets within the patch of ocean surface illuminated by the radar...
To increase the number of location options for an HF surface-wave radar (HFSWR) there is significant interest in reducing the physical size of the receive array. Reducing the aperture results in a degradation of both sensitivity and azimuth information. Azimuth accuracy may be retained by the use of high-resolution methods (such as MUSIC) that have a significantly smaller beamwidth than standard beamforming...
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