An active receiving antenna for Radio Navigation and Radio Positioning applications in S-band frequency is designed and fabricated. In this active antenna, the amplifier is integrated with the radiator which is a rectangular patch antenna. This patch antenna is analyzed with full-wave momentum method. With the developed design routine, ultra-low noise active receiving antenna can be realized. The ADS software and its full-wave Momentum is used for simulation. The experimental results show good agreement with the simulation results.

In this article, a triple-mode microstrip bandstop Filter for CDMA (1.9GHz), WCDMA (2.14GHz) and RFID (2.45GHz) is presented. The center frequencies Low insertion loss, integrated structure and deep rejection level in the passband should be mentioned as benefits for this resonator. Good concurrence between the analytical result and experimental results, full-wave simulation, transmission line model has been obtained. The filter structure is made of a perfect conductor on the top of a substrate (RT_DURROID_5880) with a relative dielectric constant of 2.21 and a height of 20mil, supported with a perfect conductor ground plan.

In this paper, the design of a broadband multi-layer microstrip antenna is presented. The broadband characteristics are the results of coupled resonances of the patch and transmission line through the resonant aperture. For this purpose, a cross-shaped transmission line, a ring slot, and a shaped ring patch are used. The simulation and measurement results indicate that a wide impedance bandwidth of 70% for |S11| < −10 dB and a perfect impedance matching 35% for |S11| < −20 dB are achieved. The gain is stable over the impedance bandwidth. The maximum gain of the proposed antenna is 8.8 dBi at 5 GHz. The radiation pattern, radiation efficiency, and cross-polarization are also suitable throughout the impedance bandwidth.