As a result of recent technical and regulatory developments, the millimeter wave (mmw) frequency band (30GHz – 300 GHz) is being adopted for a wide range of applications. Based on array signal processing technologies used for 4G and MIMO, companies are developing small active array antennas operating throughout the millimeter-wave bands. These arrays may include radiating elements and feed stru...

a newly designed printed slot antenna is presented that incorporates variable two band-notched functions for ultra-wideband (uwb) applications. the two band notches of this coplanar waveguide (cpw) fed antenna are achieved by an m-shaped slot (mss) embedded in the radiating element and a c-shaped strip(css) close to ground plane, therefore two very narrow rejected properties in the wireless loc...

Active echo cancellation is an efficient method for reducing the target detected probability. The radar cross section (RCS) of by after using active defined as (ARCS). ARCS concept, which may be used to evaluate reflection under effect multiple antennas, employed design and achieve cancellation. In this paper, numerical simulation antennas designed. direction radiation source obtained means dua...

A compact microstrip-fed antenna with dual notched bands is proposed. First, a simple basic configuration is presented for Ultra Wide Band (UWB) applications and then the dual band notched structure is extended from the UWB one. The basic structure of the UWB antenna consists of a simple square radiating patch and a ground plane with a wide square slot on back of the substrate. A semi-circle sh...

Antenna 3D pattern measurement can be a tedious and time consuming task even for antennas with manageable sizes inside anechoic chambers. Performing onsite measurements by scanning the whole 4π [sr] solid angle around the antenna under test (AUT) is more complicated. In this paper, with the aim of minimum duration of flight, a test scenario using unmanned aerial vehicles (UAV) is proposed. A pr...

In this paper, a high-efficiency and compact AlGaN/GaN heterojunction field-effect transistor (HFET) power amplifier integrated with a microstrip antenna at 7.25 GHz is presented for RF front-end circuit applications. A microstrip circular sector antenna is employed as both a radiator and frequency-dependent output load. Higher order harmonics from the HFET in nonlinear operation are reactively...

In this chapter, we describe a compact array antenna. Beamforming is achieved by tuning the load reactances at parasitic elements surrounding the active central element. The existing beam forming algorithms for this reactively controlled parasitic array antennas require long training time. In comparison with these algorithms, a faster beamforming algorithm, based on simultaneous perturbation st...

TerraSAR-X is a highly flexible X-band radar satellite. Its primary objective is the acquisition of high quality SAR images in a multitude of possible acquisition modes. The great amount of antenna patterns needed for image acquisition and correction requires an antenna model accurately describing all beams. To guarantee the required image quality, the model was verified in-orbit during the com...

A new design of coplanar waveguide (CPW)-fed antenna with circular polarization (CP) and excellent impedance matching is presented. In this design a pair of circular-shaped slits is applied to opposite corners of the slot for enhancing the impedance matching and realizes bandwidth of 134.43% across 2.98-15.20 GHz for VSWR≤2. Furthermore this structure exhibits axial ration bandwidth (ARBW) of 3...