Ferrite circulators and isolators and circuits incorporating the same

A circulator for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, three elongated high permittivity dielectric waveguides of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said waveguides being arranged in an equiangular Y-shape and integrally connected at a common junction and each including a port, a ferrite cylinder in said waveguide junction and having the axis of said ferrite cylinder disposed essentially normal to said image plane, a first magnetic pole member having a first pole face adjacent to the end of said ferrite cylinder disposed toward said image plane and a second magnetic pole member having a second pole face adjacent to the other end of said ferrite cylinder, and thin films of synthetic organic plastic resin respectively disposed between said pole faces and the adjacent surfaces of said ferrite cylinder and said waveguides, said thin films being low loss in character and having a low permittivity compared with that of said waveguides, the ratio between the thicknesses of said thin films and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, said pole members cooperating to establish a magnetic field in said ferrite cylinder extending essentially normal to said image plane whereby microwave energy in said frequency range inserted in a first port is essentially all transmitted with little attenuation to a second port and essentially none transmitted to the third port.

A switch for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, three elongated high permittivity dielectric waveguides of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said thin film being low loss in character having a low permittivity compared with that of said dielectric waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, said waveguides being arranged in an equiangular Y-shaped and integrally connected at a common junction and each including a port, a ferrite cylinder in said waveguide junction and having the axis of said ferrite cylinder disposed essentially normal to said image plane, and means for establishing a magnetic field in said ferrite cylinder extending essentially normal to said image plane of a first polarity and alternatively of a second polarity opposite in sense to said first polarity, microwave energy in said frequency range inserted in the first port when the magnetic field is of the first polarity being essentially all transmitted with little attenuation to the second port and essentially none transmitted to the third port, microwave energy in said freqeuncy range inserted in said first port when the magnetic field is of the second polarity being essentially all transmitted with little attenuation to said third port and essentially none transmitted to said second port, whereby reversing the polarity of the magnetic field through said ferrite cylinder switches transmission of the microwave energy between said second and third ports.

A switch for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, three elongated high permittivity dielectric waveguides of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said waveguides being arranged in an equiangular Y-shape and integrally connected at a common junction and each including a port, a ferrite cylinder in said waveguide junction and having the axis of said ferrite cylinder disposed essentially normal to said image plane, a first magnetic pole member having a first pole face adjacent to the end of said ferrite cylinder disposed toward said image plane and a second magnetic pole member having a second pole face adjacent to the other end of said ferrite cylinder, and thin films of synthetic organic plastic resin respectively disposed between said pole faces and the adjacent surfaces of said ferrite cylinder and said waveguides, said thin films being low loss in character and having a low permittivity compared with that of said waveguides, the ratio between the thicknesses of said thin films and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, said pole members cooperating to establish a magnetic field in said ferrite cylinder extending essentially normal to said image plane of a first polarity and alternatively of a second polarity opposite in sense to said first polarity, microwave energy in said frequency range inserted in the first port when the magnetic field is of the first polarity being essentially all transmitted with little attenuation to the second port and essentially none transmitted to the third port, microwave energy in said frequency range inserted in said first port when the magnetic field is of the second polarity being essentially all transmitted with little attenuation to said third port and essentially none transmitted to said second port, whereby reversing the polarity of the magnetic field through said ferrite cylinder switches transmission of the microwave energy between said second and third ports.

An isolator for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, an elongated high permittivity dielectric waveguide of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguide being in the range from about 0.02 to about 1.0, said thin film being low loss in character and having a low permittivity compared with that of said waveguide, a ferrite slab adjacent to one side of said waveguide extending longitudinally for a predetermined length therealong, a resistance film disposed adjacent to said ferrite slab, a first magnetic pole member having a first pole face adjacent to the surface of said waveguide disposed toward said image plane and a second magnetic pole member having a second pole face adjacent to the surface of said waveguide disposed away from said image plane, thin films of said synthetic organic plastic resin respectively disposed between said pole faces and the adjacent surfaces of said waveguide, said pole members being in general registry with said ferrite slab and cooperating to establish a magnetic field in said ferrite slab extending substantially normal to said image plane, whereby microwave energy in said frequency range is transmitted through said waveguide past said ferrite slab with little attenuation in a forward direction and with high attenuation in the reverse direction.

A switch for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, an elongated high permittivity dielectric waveguide of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said thin film being low loss in character having a low permittivity compared with that of said dielectric waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, a ferrite slab adjacent to one side of said waveguide extending longitudinally for a predetermined length therealong, a resistance film disposed adjacent to said ferrite slab, and means for establishing a magnetic field in said ferrite slab extending substantially normal to said image plane of a first polarity and alternatively of a second polarity opposite in sense to said first polarity, microwave energy in said frequency range inserted in said waveguide when the magnetic field is of the first polarity being essentially all transmitted through said waveguide past said ferrite slab with little attenuation in a first direction and with high attenuation in the reverse direction, microwave energy in said frequency range inserted in said waveguide when the magnetic field is of the second polarity being essentially all transmitted through said waveguide past said ferrite slab with little attenuation in a second direction opposite to said first direction and with high attenuation in the reverse direction, whereby reversing the direction of the magnetic field through said ferrite slab switches the direction of transmission with little attenuation of the microwave energy through said waveguide past said ferrite slab.

A modulator for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a conductive image plane, an elongated high permittivity dielectric waveguide of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said thin film being low loss in character having a low permittivity compared with that of said dielectric waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, a ferrite slab adjacent to one side of said waveguide extending longitudinally for a predetermined length therealong, a resistance film disposed adjacent to said ferrite slab, means for establishing a magnetic field in said ferrite slab extending substantially normal to said image plane of a first polarity and alternatively of a second polarity opposite in sense to said first polarity, microwave energy in said frequency range inserted in said waveguide when the magnetic field is of the first polarity being essentially all transmitted through said waveguide past said ferrite slab with little attenuation in a first direction and with high attenuation in the reverse direction, microwave energy in said frequency range inserted in said waveguide when the magnetic field is of the second polarity being essentially all transmitted through said waveguide past said ferrite slab with little attenuation in a second direction opposite to said first direction and with high attenuation in the reverse direction, and means for varying the polarity and magnitude of said magnetic field in said ferrite slab thereby to modulate the amplitude of the microwave energy transmitted through said waveguide past said ferrite slab.

An isolator for use in the frequency range of from about 1 GHz to about 1,000 GHz comprising a conductive image plane, an elongated high permittivity dielectric waveguide of finite cross section adjacent to said conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said thin film being low loss in character having a low permittivity compared with that of said dielectric waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, a first ferrite slab adjacent to one side of said waveguide extending longitudinally for a predetermined length therealong, first means for establishing a magnetic field in said first ferrite slab extending substantially normal to said image plane, a second ferrite slab adjacent to the other side of said waveguide and in transverse alignment with said first ferrite slab and extending longitudinally for a predetermined length therealong, a resistance film disposed adjacent to said second ferrite slab, and second means for establishing a magnetic field in said second ferrite slab extending substantially normal to said image plane and of the opposite polarity to the magnetic field established by said first means, whereby microwave energy in said frequency range is transmitted through said waveguide past said ferrite slabs with little attenuation in a forward direction and with high attenuation in the reverse direction.

A transceiver for use in the frequency range from about 1 GHz to about 1,000 GHz comprising a common antenna for both transmitting and receiving, a transmitter for generating electromagnetic energy in the frequency range from about 1 GHz to about 1,000 GHz;

• a local oscillator operating at a frequency different from that of said transmitter by an amount appropriate to provide a suitable I.F. frequency as a difference therebetween;
• a mixer for mixing the signal received from said antenna and the signal from said local oscillator to provide a suitable I.F. frequency;
• a circulator including a first conductive image plane, three elongated high permittivity dielectric waveguides of finite cross section adjacent to said first conductive image plane, a thin film of synthetic organic plastic resin disposed between and secured to both said image plane and said waveguides, said thin film being low loss in character having a low permittivity compared with that of said dielectric waveguide, the ratio between the thickness of said thin film and the square root of the cross-sectional area of said dielectric waveguides being in the range from about 0.02 to about 1.0, said waveguides being arranged in an equiangular Y-shape and integrally connected at a common junction and each including a port, a ferrite cylinder in said waveguide junction and having the axis of said ferrite cylinder disposed essentially normal to said first image plane, and first means for establishing a magnetic field in said ferrite cylinder extending essentially normal to said first image plane, the port of said first waveguide being connected to said antenna and the port of said second waveguide being connected to said mixer. and the port of said third waveguide being connected to said transmitter, whereby microwave energy in said frequency range inserted in said first port from said antenna is essentially all transmitted with little attenuation to said mixer via said second port and essentially none transmitted to said transmitter via said third port, and whereby microwave energy from said transmitter via said third port is essentially all transmitted with little attenuation to said antenna via said first port and essentially none transmitted to said mixer via said second port;
• and an isolator including a second conductive image plane, a fourth elongated high permittivity dielectric waveguide of finite cross section adjacent to said second conductive image plane, a ferrite slab adjacent to one side of said fourth waveguide extending longitudinally for a predetermined length therealong and being disposed essentially normal to said image plane, a resistance film disposed adjacent to said ferrite slab, and second means for establishing a magnetic field in said fourth waveguide and said ferrite slab extending essentially normal to said second image plane, and connections between one end of said fourth waveguide and said local oscillator and between the other end of said fourth waveguide and said mixer, whereby microwave energy in said frequency range is transmitted from said local oscillator through said waveguide past said ferrite slab to said mixer with little attenuation, and whereby microwave energy from said mixer transmitted toward said isolator is transmitted through said isolator with high attenuation thereby to protect said local oscillator.