Superiority of poly-alphabetic sequences (PAS) for pulse compression radar over the binary and ternary sequences was established earlier. However, the enlarged alphabets in poly–alphabetic sequences deteriorate the noise and Doppler robustness at higher lengths in high resolution radar (HRR) systems. In this paper, poly-semantic sequences (PSS) with restricted alphabet {+1,-1} are considered an...

We present a compressive radar design that combines multitone linear frequency modulated (LFM) waveforms in the transmitter with classical stretch processor and sub-Nyquist sampling receiver. The proposed illumination scheme has fewer random elements resulting reduced storage complexity for implementation calibration than previously designs based on stochastic waveforms. analyze this task of jo...

The newly emerging theory of compressed sensing (CS) enables restore of a sparse signal from inadequate number of linear projections. Based on compressed sensing theory, a new strategy of high-resolution range profiling of stepped-frequency (SF) radar with missing pulses is proposed. If a certain part of received pulses are missing, we demonstrate the proposed method is capable of reconstructin...

The new generation of Synthetic Aperture Radar (RADARSAT-2, TerraSAR-X, ALOS, . . . ) allows us to capture Earth surface images with very high resolution. Therefore the possibility to characterize objects has become more and more attainable. Moreover, the short revisit time propertie of these satellites enables the development of techniques of change detection and their applications. Sphericall...

A new fused Bayesian maximum entropy–variational analysis (BMEVA) method for enhanced radar/synthetic aperture radar (SAR) imaging is addressed as required for high-resolution remote sensing (RS) imagery. The variational analysis (VA) paradigm is adapted via incorporating the image gradient flow norm preservation into the overall reconstruction problem to control the geometrical properties of t...

Since 1986 the Electromagnetics Institute, the Technical University of Denmark, has designed, build and tested a high resolution airborne C-band Synthetic Aperture Radar, SAR. The first test flights took place in November and December 1989. The radar design has been based on digital technology to the largest possible extent, to make the system as adaptable as possible. This has resulted in a ve...

Efficient digital phased array beams require a high resolution timing vector. The timing coefficients cause speed bottleneck for FPGA implementation of beam forming in the HF frequency range. In this paper we present polyphase interpolator to overcome the speed limitation of FPGA implementation of digital beamforming (DBF) for ionospheric radar. The radar requires a constant phasing vector to s...