International Journal

The paper proposes a new design for a single-arm, rectangular, spiral antenna (SARSA) with a wide azimuth space coverage. The antenna, operating at around 3.3 GHz, is capable of steering the beam in four separate directions in the azimuth plane. Only three DC signals are required to control the seven PIN diodes attached along the spiral arm. The antenna has a 200-MHz-bandwidth around 3.3 GHz with

This paper presents an optimization circuit model of multiconductor transmission lines in the time domain. Several methods allow calculation of the currents and the tensions distributed on the uniform transmission line. Most of these methods are limited to lines with constant losses, and only for linear loads. The macro-model we propose, using Pade approximant, employs more variables and allows it

In this paper, four new wideband small antennas based on the composite right/left-handed transmission line (CRLH-TL) structures are designed, tooled, and made. The proposed antennas are introduced with best in size, bandwidth, and radiation patterns. The physical size and the operational frequency of the antennas depend on size of the unit cells and the equivalent transmission line model parameter

This paper presents power results of L-band packaged hybrid amplifiers using InAlN/GaN/SiC HEMT power dies. The high-power densities achieved both in pulsed and continuous wave (cw) modes confirm the interest of such technology for high-frequency, high-power, and high-temperature operation. We present here record RF power measurements for different versions of amplifiers. Up to 260 W, i.e. 3.6 W/m

This paper presents a method for automatic construction of stable and passive scalable macromodels for parameterized frequency responses. The method requires very little prior knowledge to build the scalable macromodels thereby considerably reducing the burden on the designers. The proposed method uses an efficient scattered sequential sampling strategy with as few expensive simulations as possibl

In this paper, a new multi-layered triple-passband bandpass filter using embedded and stub-loaded stepped impedance resonators (SIRs) is proposed. The filter is designed to have triple-passband at 1.8, 2.4, and 3.5 GHz. The 1st and 2nd passbands (1.8/2.4 GHz) are simultaneously generated by controlling the impedance and length ratios of the embedded SIRs (on top layer). The 3rd passband (3.5 GHz)

This paper presents a new concept for the fine tuning of high-Q bandpass filters to compensate for small response deviations due to manufacturing tolerances and temperature variations. Discrete frequency tuning steps are obtained using a rectangular waveguide resonator loaded with a reconfigurable E-plane circuit. Ohmic micro electromechanical systems (MEMS) switches can be placed along thin E-pla