synthetic aperture radar (sar), which has been widely used for earth remote sensing, provides high resolution, day-and-night and weather-independent images for a multitude of applications. design of sar sensors has had some considerations, associated to sar systems issues (microwave propagation, antenna, orbit design and etc.). altitude and attitude errors of sar sensor have a direct effect on ...

We consider passive synthetic aperture imaging where a single moving receiver antenna records signals that are generated by distant unknown noise sources and backscattered by one or several reflectors. The reflectors can be imaged by migrating the autocorrelation functions of the received signals. We compare this passive synthetic aperture imaging with the usual, active synthetic aperture imagi...

Synthetic aperture radar (SAR) is an active remote sensing tool operating in the microwave range of the electromagnetic spectrum. It uses the motion of the radar transmitter to synthesize an antenna aperture much larger than the actual antenna aperture in order to yield high spatial resolution radar images (Curlander & McDonough, 1991). It has been applied to military survey, terrain mapping, a...

This paper presents a novel structure of a frequency-reconfigurable microstrip antenna fed with an aperture-coupled technique and stacked patch technology. The proposed antenna design has a unique structure; the radiating elements (top and bottom patch) are sorted in stacked substrate layers to indicate the different operating frequencies. One PIN diode switch integrated at the feedline is reco...

A novel TEM horn antenna placed in a solid dielectric medium is proposed for microwave imaging of the breast. The major design requirement is that the antenna couples the microwave energy into the tissue without being immersed itself in a coupling medium. The antenna achieves this requirement by: 1) directing all radiated power through its front aperture, and 2) blocking external electromagneti...

During the past few decades, there has been growing interest in the use of microwave and millimeter wave radiometers for remote sensing of the Earth. Due to the need of large antennas and scanning mechanism, the conventional real aperture radiometer becomes infeasible for high spatial resolution application. Interferometric aperture synthesis was suggested as an alternative to real aperture rad...

Certain applications such as RFID, on body sensors network, microwave systems usually require good matching impedance, high gain and large bandwidth for their antennas. The aperture coupled antenna is one candidate that can provide high gain large bandwidth and little packaging. Thus, it would be of interest to enhance the characteristics of a singly-fed aperture antenna used for Zigbee applica...

The selection of a near-field or far-field ground-penetrating radar (GPR) model is an important question for an accurate but computationally effective characterization of medium electrical properties using full-wave inverse modeling. In this study, we determined an antenna height threshold for the near-field and farfield full-wave GPR models by analyzing the variation of the spatial derivatives...

This paper presents a high-gain cavity resonant antenna (CRA), consisting of an FSS layer placed above an aperture coupled microstrip patch antenna (ACMPA). Geometry of the proposed FSS superstrate is highly reflective with |Γ > 0.9|. Ray-tracing method has been employed for determining the resonant condition of the antenna. ACMPA operating at S-band is serving as a feeding source. The coupling...

In mobile communication, a less explored technique to mitigate fading effects is based on the physical parameter of the transmitter by varying the physical dimension of the transmitting antenna. This paper deals with a self adaptive system to eliminate severe fading effects in different multi antenna set-ups by adaptively updating the effective aperture of the transmitting antenna. The system c...