A feeder circuit comprising: - a first line having a first end and a second end; - a second line having a first end and a second end; - a third line having a first end and a second end; - a fourth line having a first end and a second end; - a first combiner connected to the second end of the first line and the second end of the second line, and configured to combine signals output from both the second end of the first line and the second end of the second line; and - a second combiner connected to the second end of the third line and the second end of the fourth line, and configured to combine signals output from both the second end of the third line and the second end of the fourth line, characterized in that the feeder circuit further comprises: - a first coupling portion configured to electrically couple a portion of the first line and a portion of the third line to each other; and - a second coupling portion configured to electrically couple a portion of the second line and a portion of the fourth line to each other, and in that the feeder circuit is configured to satisfy a condition expressed as: φ 3 + θ 1 + θ 2 + θ 3 = φ 4 + θ 4 + θ 5 + θ 6 + 180 ° × A, where φ3 denotes a phase of a signal input to the first end of the third line, φ4 denotes a phase of a signal input to the first end of the fourth line, θ1 denotes an electrical length of a path extending from the first end of the third line to the first coupling portion along the third line, θ2 denotes an electrical length of the first coupling portion, θ3 denotes an electrical length of a path extending from the first coupling portion to an output end of the first combiner along the first line, θ4 denotes an electrical length of a path extending from the first end of the fourth line to the second coupling portion along the fourth line, θ5 denotes an electrical length of the second coupling portion, θ6 denotes an electrical length of a path extending from the second coupling portion to the output end of the first combiner along the second line, and A denotes an odd number. - a first line having a first end and a second end; - a second line having a first end and a second end; - a third line having a first end and a second end; - a fourth line having a first end and a second end; - a first combiner connected to the second end of the first line and the second end of the second line, and configured to combine signals output from both the second end of the first line and the second end of the second line; and - a second combiner connected to the second end of the third line and the second end of the fourth line, and configured to combine signals output from both the second end of the third line and the second end of the fourth line, characterized in that - a first coupling portion configured to electrically couple a portion of the first line and a portion of the third line to each other; and - a second coupling portion configured to electrically couple a portion of the second line and a portion of the fourth line to each other, and in that the feeder circuit is configured to satisfy a condition expressed as: φ 3 + θ 1 + θ 2 + θ 3 = φ 4 + θ 4 + θ 5 + θ 6 + 180 ° × A, where φ3 denotes a phase of a signal input to the first end of the third line, φ4 denotes a phase of a signal input to the first end of the fourth line, θ1 denotes an electrical length of a path extending from the first end of the third line to the first coupling portion along the third line, θ2 denotes an electrical length of the first coupling portion, θ3 denotes an electrical length of a path extending from the first coupling portion to an output end of the first combiner along the first line, θ4 denotes an electrical length of a path extending from the first end of the fourth line to the second coupling portion along the fourth line, θ5 denotes an electrical length of the second coupling portion, θ6 denotes an electrical length of a path extending from the second coupling portion to the output end of the first combiner along the second line, and A denotes an odd number.