This paper presents a novel design of compact contra-directional coupler with high directivity for high-power monitoring in frequency. Microstrip parallel coupled lines are widely used directional couplers; however, they show poor inherently. Their has been improved by many works. However, the suggested approaches often result other limitations, such as weak structure monitoring, or larger size...

Paired-pulse stimulation, the application of two stimuli in close succession, is a useful tool to investigate cortical excitability. Suppression of the second response after short interstimulus intervals characterizes paired-pulse behavior. Although paired-pulse suppression is often studied as a marker of cortical excitability in humans, little is known about the influence of stimulation intens...