Introduction Measurement and control of gain and reflected power in wireless transmitters are critical auxiliary functions that are often overlooked. The power reflected back from an antenna is specified using either the Voltage Standing Wave Ratio (VSWR) or Reflection Coefficient (also referred to as Return Loss). Poor VSWR can cause shadowing in a TV broadcast system as the signal reflected o...

Nowadays, microwave frequency systems, in many applications are used. Regardless of the application, all microwave communication systems are faced with transmission line matching problem, related to the load or impedance connected to them. The mismatching of microwave lines with the load connected to them generates reflected waves. Mismatching is identified by a parameter known as VSWR (Voltage...

The design of reconfigurable active antennas requires an efficient system simulation in order to analyze the impact of other components on the array pattern, especially the Power Amplifiers (PA) effect. Therefore, the performance prediction of PA on Tx-Rx chains is important. This paper presents a behavioral model of a PA, which is able to take into account the load impedance mismatch with a VS...

The effects of parasitic elements on the voltage standing wave ratios (VSWR’s) of two antennas are investigated. First, a parasitic monopole is used for a normal-mode helical antenna. The VSWR investigation shows that dual-frequency operation is obtained by the parasitic element effects. The dualfrequency operation is revealed as a function of monopole position above a ground plane (monopole he...

A WLAN band notched compact ultra-wideband (UWB) microstrip monopole antenna with stepped geometry is proposed. A L-slot loaded modified mushroom type Electromagnetic Band Gap (EBG) is designed, analyzed and used to realize notched band characteristics for wireless local area network (WLAN) in the UWB frequency range. The proposed antenna having partial ground plane is fabricated on a low cost ...

Dual-polarized antenna is widely used in communication systems such as ECM and DF systems. In this paper a novel doubleridged horn antenna with dual polarizations is introduced for frequency range of 8–18 GHz. Common double ridged horn antennas have single polarization over the operating frequency. We have used five layers polarizer to provide dual polarizations performance of the doubleridged ...