Abstract: In a circularly polarized wave antenna apparatus including a non-reciprocal transmission line apparatus having forward and backward propagation constants different from each other, the non-reciprocal transmission line apparatus includes a transmission line part for a microwave, a series branch circuit equivalently including a capacitive element, and a shunt branch circuit branched from the transmission line part and equivalently includes an inductive element. The non-reciprocal transmission line apparatus is formed in a nonlinear shape and magnetized in a magnetization direction different from a propagation direction of the microwave.

Abstract: In a circularly polarized wave antenna apparatus including a non-reciprocal transmission line apparatus having forward and backward propagation constants different from each other, the non-reciprocal transmission line apparatus includes a transmission line part for a microwave, a series branch circuit equivalently including a capacitive element, and a shunt branch circuit branched from the transmission line part and equivalently includes an inductive element. The non-reciprocal transmission line apparatus is formed in a nonlinear shape and magnetized in a magnetization direction different from a propagation direction of the microwave.

Abstract: When a phase constant in a first mode of propagation in the forward direction is ?p, and a phase constant in a second mode of propagation in the backward direction is ?m, respective first and second electrical lengths of stub conductors are set so that a function of nonreciprocal phase shift amount ?NR=(?p??m)/2 with respect to an operating angular frequency comes close to a function ?NRZ with respect to an operating angular frequency, when beam squint of such a phenomenon that a radiation direction of electromagnetic waves radiated from a nonreciprocal transmission line apparatus changes in accordance with frequency does not occur in the vicinity of an intersection of a dispersion curve representing a relation between the phase constant ?p and the operating angular frequency and a dispersion curve representing a relation between the phase constant ?m and the operating angular frequency.

Abstract: When a phase constant in a first mode of propagation in the forward direction is ?p, and a phase constant in a second mode of propagation in the backward direction is ?m, respective first and second electrical lengths of stub conductors are set so that a function of nonreciprocal phase shift amount ?NR=(?p??m)/2 with respect to an operating angular frequency comes close to a function ?NRZ with respect to an operating angular frequency, when beam squint of such a phenomenon that a radiation direction of electromagnetic waves radiated from a nonreciprocal transmission line apparatus changes in accordance with frequency does not occur in the vicinity of an intersection of a dispersion curve representing a relation between the phase constant ?p and the operating angular frequency and a dispersion curve representing a relation between the phase constant ?m and the operating angular frequency.