The invention provides a non-reciprocal circuit element, which can ensure the transmission
frequency band required by the input and output signals, reduce the loss on the
signal frequency, and increase the
return loss of the input and output terminals at the same time. The non-reciprocal circuit element of the present invention comprises: a plate-shaped
magnetic core (1), placed in a DC
magnetic field, the upper surface is at right angles to the direction of the DC
magnetic field, and 3 central conductors (2, 3, 4) are overlapped at equal angular intervals placed on the roughly central part of the
magnetic core (1), one end is used as the input and output terminals (2c, 3c, 4c), and the other end is used as the ground terminal (2d, 3d, 4d); make the center part to the ground terminal (2d , 3d, 4d) between the central conductor (2, 3, 4) unit length
inductance ratio of the central part to the input and output terminals (2c, 3c, 4c) between the central conductor (2, 3, 4) unit The
inductance of the length is small.