PURPOSE: To make the filter small and to reduce the cost by employing inter- component connection lines to interconnect an input/ output terminal, transmission inductive filter and a reception inductive filter for 1st and 2nd lines being parts of the branching filter circuit so as to allow the lines not to occupy a wide area on a board as components of the branching filter circuit.
CONSTITUTION: An ANT (input/output terminal) terminal 51 and an input terminal 52 are interconnected by a line 60 whose length is l12, the input terminal 52 and an input terminal 53 interconnected by a line 61 whose length is l23, and the input terminal 52 and ground are interconnected by a line 62 whose length is l20. Then the lines 60,61 whose length is respectively l12, l23 are used as parts of the branching filter circuit and a transmission filter 56 and a reception filter 57 are adjusted together with the lines 60,61 whose length is respectively l12, l23. Thus, the deterioration in the characteristic due to the lines 60, 61 whose length is respectively l12, l23 is reduced, the occupied area as the branching filter circuit is reduced, the size is made small and the cost is reduced.
GUNJI KATSUHIKO
ONISHI NORIO
MASHITA AKIRA
ICHIKAWA KOICHI
