The design of Cyclotron CYCHU-10 has been carried out at Huazhong University of Science and Technology (HUST). Because of the low centre frequency (99MHz) of its RF system, we should choose suitable directional couplers for the RF system which is supposed to be highdirectivity and tight-structure. This paper analyzes and synthesizes kinds of directional couplers, especially microstrip structure...

This paper presents the design of a bandpass filter using directional coupler. The concept of transerval filters is applied to design of microwave filters. The directional coupler is used as a transversal filtering element. This is achieved by loading the coupled ports of the filter with open-circuited stubs. The dependence of filter characteristics on the stub lengths and impedances is demonst...

The propagation of temporal solitary waves, formed in the second-order nonlinear medium, is analysed in waveguide directional couplers. The influence of the thirdorder nonlinearity on the switching effect is also presented. Recently, the great effort of nonlinear guided-wave phenomena research is focused on the cascaded second-order process which can produce relatively large intensity-dependent...

We experimentally demonstrate a terahertz-bandwidth photonic differentiator employing a silicon-on-insulator directional coupler. The integrated waveguide coupler with two identical paralleled strip waveguides achieves a first-order differentiator when full energy coupling is met from one waveguide to another. The integrated waveguide coupler can offer different operation bandwidths by changing...

We present the design of ALMA Band 5 sideband separation mixer based on Niobium superconducting SIS junctions and first experimental results for the double side band mixer. In this mixer the LO injection circuitry is integrated on the mixer substrate using a microstrip line directional coupler with slot-line branches in the ground plane. The isolated port of the LO coupler is terminated by a wi...

in this paper a novel design of all-optical half-subtractor based on nonlinear directional coupler is proposed. by using four waveguides and appropriately adjusting the refractive indices and selecting the proper length of waveguides, halfsubtractor function can be obtained. the operation of this function is simulated by rsoft cad-layout (beamprop) simulator. the simulation results confirm the ...