A fourth-degree Substrate Integrated Waveguide (SIW) crossed coupled band pass filter for WLAN band is designed by using a new negative coupling structure. It consists of two U shape microstrip lines on top and bottom planes with via holes at the center of them. This paper investigates the phase characteristics of negative and positive coupling structures and their effects. The design, fabricat...

In this pare, a wideband three-order bandpass filter (BPF) is proposed. The proposed wideband filter is designed using the substrate integrated waveguide (SIW) structure by loading T-shape slots. A BPF with two resonators is formed by etching T-shape slots with different size on the top metal plane of the SIW structure. The filter is investigated with the theory of coupled resonator circuits. T...

this paper presents an innovative active power filter design method to simultaneously compensate the current harmonics and reactive power of a nonlinear load. the power filter integrates a passive power filter which is a rl low-pass filter placed in series with the load, and an active power filter which comprises an rl in series with an igbt based voltage source converter. the filter is assumed...

A sodium silicate-based chemical grout was used in the Karkheh dam site in order to examine the performance of the chemical grouting technique for stabilization of the dam's filter material. Karkheh, an embankment dam with the reservoir capacity of about 7.4 billion cubic meter at the maximum water level, is the largest dam in Iran. The grouting works performed at the dam site, were part of the...

Lights near 560 nm appear brighter when flickered, whereas lights near 520 or 650 nm appear yellower. Both effects are consistent with signal distortion within the visual pathway--brightness changes at an expansive nonlinearity, and hue shifts at a compressive one. We previously manipulated the distortion products generated by each nonlinearity to extract the temporal properties of stages of th...

a fourth-degree substrate integrated waveguide (siw) crossed coupled band pass filter for wlan band is designed by using a new negative coupling structure. it consists of two u shape microstrip lines on top and bottom planes with via holes at the center of them. this paper investigates the phase characteristics of negative and positive coupling structures and their effects. the design, fabricat...

Portable wireless communication systems are increasingly in demand small sizes for human convenience. In systems, the performance, size, and unit cost very important. A band−pass filter is important to sharp cut–off frequency characteristics, selectivity systems. The has three types of techniques transmission−zero method, stub−loaded resonator, stepped impedance resonator cut−off characteristic...

This article proposes an alternative method for designing miniature waveguide filters based on locally resonant metamaterials. Implementation of ultra-small metamaterial (metafilters) using the subwavelength direction mechanism in hollow waveguides loaded with small resonators. In particular, composite pin are used, constructed from a metal tube set pins that spaced over deep distances. such st...