Patent ID: 7973617
Filing Date: 2011-07-05
Classification: H01P,H01Q

Abstract:
1. An unequal three-way divider for dividing an input signal into three in-phase signals whose power ratio is different between a center and both ends, the unequal three-way divider comprising: an input terminal to which the input signal is input; three output terminals for outputting respective one of three-divided signals; and three transmission paths provided between the input terminal and the three output terminals, and branched from the input terminal and connected to the respective three output terminals, wherein: a transmission path connected to a center output terminal of the three output terminals, wherein the transmission path connected to the center output terminal is one of the three transmission paths, and has a first transmission line and a second transmission line which are connected in series with each other, wherein an electrical length of the second transmission line is ¼ wave length; each of remaining two transmission paths from the three transmission paths connected to a respective one of the three output terminals other than the center output terminal at both ends out of the three transmission paths has a third transmission line and a fourth transmission line which are connected in series with each other, wherein an electrical length of the fourth transmission line is ¼ wave length; an absorption resistor is provided between a connection point between the first transmission line and the second transmission line and a connection point between the third transmission line and the fourth transmission line; and an electrical length of the first transmission line or an electrical length of the third transmission line is ¼ wave length, wherein the transmission path connected to the center output terminal has a fifth transmission line connected in series with the second transmission line; each of the remaining two transmission paths connected to the respective one of the three output terminals other than the center output terminal at both ends has a sixth transmission line connected in series with the fourth transmission line; and a relationship between a difference ΔL1 in electrical length between the first transmission line and the third transmission line and a difference ΔL2 in electrical length between the fifth transmission line and the sixth transmission line is set as ΔL2=−ΔL¼; wherein characteristic impedances of the transmission lines and a resistance value of the absorption resistor are given, in order to implement the power ratio of 1:k where Z 10 is a characteristic impedance of each of the fifth transmission line and the sixth transmission line, Z 12 is a characteristic impedance of the first transmission line, Z 14 is a characteristic impedance of the second transmission line, Z 13 is a characteristic impedance of the third transmission line, Z 15 is a characteristic impedance of the fourth transmission line, and R 10 is the resistance value of the absorption resistor.