MICROSTRIP DOUBLE-BRANCH DIRECTIONAL COUPLER AND RADAR LEVEL GAUGING SYSTEM

摘要

Disclosed are a microstrip double-branch directional coupler and a radar level gauging system. The microstrip double-branch directional coupler comprises: a main line 1, a first branch line 2, an auxiliary line 3, a second branch line 4, four ports, and four port leads; the main line 1, the first branch line 2, the auxiliary line 3, and the second branch line 4 are connected in sequence in an end-to-end manner so as to form a closed ring; the length of each of the main line 1, the first branch line 2, the auxiliary line 3, and the second branch line 4 is λ/4, λ being a wavelength at a center frequency of the microstrip double-branch directional coupler; the port lead corresponding to each port is perpendicular to a tangent line of the closed ring at the port, and extends to the outside of the closed ring.