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A binary programmable metasurface is designed to generate arbitrary images in the near-field region. By adequately changing the coding sequences of the metasurface, these images can be detected by a single fixed probe, hence realizing direct transmission of near-field images.

With the developement of metamaterials in recent years, more and more interests have been attracted in the potential applications of these novel materials. Metamaterials are usually composed of periodic subwavelength units, which can produce electric or magnetic responses under the excitation of external incident waves. Since the characteristic dimensions of the composing units are far smaller than the working wavelength, effective medium theory can be utilized to describe the electromagnetic properties of the periodic structures. A number of applications have been verified by experiments like invisible cloaks, microwave lens and tunneling structures [1–3].

The UTD analysis to the diffraction of electromagnetic (EM) waves by smoothly convex surfaces is of great importance in many problems, such as the EM compatibility, the analysis of coupling between two antennas, and the estimation of scattering properties. When a ray illuminates on the curved surface at grazing incidence, the ray-propagating direction is tangent to the curved surface at the incident point, and then surface rays are launched. These surface rays, or creeping waves, propagate along geodesic paths on the convex surface starting from the incident point. Hence the ray tracing of creeping waves on the convex surface is a key process in the UTD method. Usually, some typically geometric objects are used to approximate a certain of objects for engineering applications. However, it is difficult to use such typically geometric objects to approximate arbitrarily-shaped objects, which limits the application of the UTD method.

A novel microstrip phase shifter is presented using metamaterial structures. The phase shifter is composed of complementary split-ring resonators (CSRR) and complementary electric-LC (CELC) resonators to realize the 180 degrees of phase difference. The added insertion loss is only 1.33 dB at 16.8 GHz in a transmission line, which is originally 64.5 degrees long. Moreover, a new design method to control the phase difference by changing the effective permittivity and permeability is proposed.

This article presents the design of an inexpensive, efficient, and electrically small antenna based on metamaterial- inspired structure fed by the coplanar waveguide (CPW). The size of the proposed antenna is 12 mm x 12 mm with the resonant frequency of 1.47 GHz. Details of the proposed antenna are presented, with full-wave simulation results to support the design.

This paper concerns the simulation of inverse synthetic aperture radar (ISAR) image for radar targets based on the shooting and bouncing ray (SBR) method. Contrary to the conventional approach where the ISAR image is obtained by inverse Fourier transforming to the scattering field, we adopt a newly-developed method [8], where the Fourier transformation has been merged into the SBR algorithm. Such a method has been improved and used in the imaging of real-size aircraft. High resolution two-dimensional ISAR images have been obtained. Hence such a method is considered as a general tool for the characterization of large and complex targets.