We present a novel reflective quarter-wave plate comprised of subwavelength meanderline elements. The device is operational over the long-wave infrared (LWIR) spectrum, with significant spectral and angular bandwidths. Power reflection is approximately 70% over the majority of the LWIR. Efficient conversion from a 45° linear polarization state into circular polarization is demonstrated from fin...

The modern mobile communication systems requires high gain, large bandwidth and minimal size antenna’s that are capable of providing better performance over a wide range of frequency spectrum.This paper presents the design of microstrip rectangular patch antenna with center frequency at 1.176GHz for IRNSS application. The array of four by one (1x4) patch array microstrip rectangular antenna wit...

earthquakes travel times inversion for determination of velocity structure of crust is one of the most important objectives in seismology. in the simultaneous inversion method, the parameters of earthquakes and velocity model are determined initially and are improved during inversion steps. in this study, we have used more than 22000 calculated travel times for first arrivals of 6000 earthquake...

This paper presents lumped dual-frequency impedance transformers for frequency-dependent complex loads. According to different dual-frequency allocations of a complex load in Smith chart, three types of impedance matching networks are presented respectively. Several kinds of lumped circuit blocks are used as basic elements for constructing these transformers with design formula deduced. Various...

We demonstrate optically thin quarter-wave plates built with metasurfaces that generate high-quality circularly polarized light over a broad wavelength range for arbitrary orientation of the incident linear polarization. The metasurface consists of an array of plasmonic antennas with spatially varying phase and polarization responses. Experimentally demonstrated quarter-wave plates generate lig...

spatial distribution of electric field amplitude has an essential role in laser-induced damagemulti-layer coating. a new method introduced in this paper to reduce the electric field intensityeffectively within the high index layers in multi-layer reflectors that are irradiated by high power lasers.the design is based on specific non-quarter wave pairs, assuming the number of layers is held cons...

In this paper the recently developed semi-analytic method to solve the free-surface wave interaction with a thin elastic plate is extended to the case of a plate of finite thickness. The method used is based on the reformulation of the differential-integral equation for this problem. The thickness of the plate is chosen such that the elastic behavior of the plate can be described by means of th...