LOW-PASS FILTER WITH DIRECTIONAL COUPLER AND PORTABLE TELEPHONE SET USING THE SAME

摘要

An integrated component providing the function of both a conventional directional coupler and a low-pass filter having two attenuation poles at a specified frequency band without changing the line length. A stab lines 108 and 109 are connected to both ends of a main transmission line 105 of a directional coupler. A frequency of the attenuation poles is adjustable by characteristics impedance, terminating conditions, and line length of the stab lines. <IMAGE>