Miniaturisation of branch line couplers with a compact transmission line topology based on coupled line section

Using a VIA-Less CRLH Transmission Line to Design Compact Wilkinson Power Dividers and Rat-Race Couplers

A method for design and implementation of a compact via-less Composite Right/Left-Handed Transmission Line (CRLH TL) is presented. By introducing a new circuit model, the CRLH transmission line behavior is studied versus the parameters variations to achieve the desired characteristic impedance and electrical length. Then a compact quarter wavelength CRLH transmission line with 70 Ω characte...

Realization of a Compact Branch-line Cou- Pler Using Quasi-fractal Loaded Coupled Transmission-lines

An extremely compact branch-line coupler operating at 900MHz is presented without the use of via-holes, multilayered technique, or air-bridged. The technique presented here uses the concept of fractals to load a coupled transmission-line in order to realize a compact quarter-wavelength transmission-line, which forms the couplers arms. It is shown that the proposed branch-line coupler’s performa...

Coupled-Line Couplers Based on the Composite Right/Left-Handed (CRLH) Transmission Lines

A Compact Ultra-Wideband Filter Based on Left Handed Transmission Line by Using Complementary Split Ring Resonators and Series Capacitor

A compact and sharp rejection UWB microstrip bandpass filter is developed using left handed metamaterials. For realizing a backward-wave propagation medium, two split ring resonator (CSRR) in the back substrate side and also one series capacitor etched in the host line, are used to produce a negative effective ε and μ, simultaneously. Moreover, in the proposed structure, two doublets parallel c...

A Compact Coupled-Line Multiband Microstrip Antenna

A multiband microstrip antenna is proposed in this paper. By using a circular slot at the ground plane, the circular radiation at the antenna frequency resonances has been achieved. A patch is designed with a coupled U-shaped line. To gain resonance at the lower frequency, a microstrip line is introduced at the middle of the circular slot. The assessment of the proposed antenna shows good agree...