High power diode phase shifter

Claim 2

A voltage-controlled phase shifter comprising a rectangular waveguide, arrays of probes in said waveguide disposed in planes spaced a quarter wavelength apart, a plurality of diodes outside of said waveguide, one for each probe, a plurality of stripline circuits, one for each probe, coupling each of said probes to a different one of said diodes, each stripline circuit being adjusted in geometry to provide a small value of susceptance in shunt with said waveguide, a plurality of capacitors, a different one connected in parallel with a separate diode and stripline circuit connected in series, and means for selectively forward and reverse biasing each of said diodes.

Claim 3

A voltage-controlled phase shifter as defined in claim 1 wherein each of said stripline circuits includes a shorted shunt stub next to a probe, an open-circuit shunt stub next to a diode, and a narrow section connecting said shunt stubs to provide series inductance.

Claim 4

In a rectangular waveguide for a particular propagation mode, a voltage-controlled phase shifter comprising a plurality of diode switching circuits disposed in arrays along said waveguide a quarter wavelength apart to form phase-shift sections of a transmission phase shifter, each array comprising a plurality of diodes mounted outside of said waveguide, a plurality of probes disposed in a plane normal to the walls of said waveguide, one probe for each diode, each of said probes being positioned inside said waveguide in said plane for picking up electromagnetic energy, and a plurality of circuit means coupling said probes to said diodes, a separate circuit means for each diode providing a small value of susceptance in shunt with said waveguide which can be changed by a small amount when the coupled diode is switched from a forward biased to a reverse biased condition, each of said circuit meaNs includes a capacitor and means for selectively providing forward and reverse bias potential for said diodes, a stripline circuit coupling a probe to a diode, said stripline circuit being adjusted in geometry to provide a shorted shunt stub next to said probe, the end of said shorted shunt stub being connected to said waveguide, an open-circuit shunt stub next to said diode, a section connecting said shunt stubs, said section being sufficiently narrow to provide series inductance between said shunt stubs, a section connecting said shorted shunt stub outside of said waveguide to said probe, and a section connecting said open-circuited shunt stub to said diode, said diode being connected in series between said stripline circuit and said means for selectively providing forward and reverse biasing potential, and means for connecting said capacitor between said waveguide and said diode at a terminal to which said biasing potential means is connected.

Claim 5

In a rectangular waveguide for a particular propagation mode, a voltage-controlled phase shifter comprising a plurality of diode switching circuits disposed in arrays along said waveguide a quarter wavelength apart to form phase-shift sections of a transmission phase shifter, each array comprising a plurality of diodes mounted outside of said waveguide, a plurality of probes disposed in a plane normal to the walls of said waveguide, one probe for each diode, each of said probes being positioned inside said waveguide in said plane for picking up electromagnetic energy, and a plurality of circuit means coupling said probes to said diodes, a separate circuit means for each diode providing a small value of susceptance in shunt with said waveguide which can be changed by a small amount when the coupled diode is switched from a forward biased to a reverse biased condition, each of said circuit meaNs includes a capacitor and means for selectively providing forward and reverse bias potential for said diodes, a stripline circuit coupling a probe to a diode, said stripline circuit being adjusted in geometry to provide a shorted shunt stub next to said probe, the end of said shorted shunt stub being connected to said waveguide, an open-circuit shunt stub next to said diode, a section connecting said shunt stubs, said section being sufficiently narrow to provide series inductance between said shunt stubs, a section connecting said shorted shunt stub outside of said waveguide to said probe, and a section connecting said open-circuited shunt stub to said diode, said diode being connected in series between said stripline circuit and said means for selectively providing forward and reverse biasing potential, and means for connecting said capacitor between said waveguide and said diode at a terminal to which said biasing potential means is connected.

Claim 6

The combination of claim 3, wherein 2N diode switching circuits are included in each array, N is a whole integer separately selected for each array, and N probes are inserted into said waveguide through slots on each of two opposite sides, each of N probes on one side being disposed to pick up an equal amount of power for said particular waveguide propagation mode as each of N probes on the other side of said waveguide.

Claim 7

The combination of claim 4 wherein N is selected for each array to be equal except for end arrays, and N is selected for each end array to be less than for intermediate arrays for the purpose of providing lighter loading at the ends of said phase shifter.

Claim 8

A voltage-controlled phase shifter comprising a rectangular waveguide for a particular propagation mode, a plurality of switching diodes grouped in successive arrays spaced a quarter wavelength apart to form phase shift sections between diode arrays, said diodes being mounted outside of said waveguide, a plurality of probes, one for each diode, each probe being inserted into said waveguide through a slot and all probes associated with diodes of one array being disposed in a single plane normal to the walls of said waveguide axis, a control voltage terminal outside of said waveguide for receiving selectively forward and reverse bias voltage for each diode, a separate stripline circuit for connecting each diode in series between said terminal and an associated one of said probes, said stripline circuit including a shorted shunt stub next to said associated one of said probes, an open-circuit shunt stub, and a narrow section connecting said shunt stubs to provide an inductance therebetween, and further including coupling sections at each end of said narrow section for connecting said stripline circuit in series between a diode and an associated one of said probes, and a separate capacitor connected between said terminal and said waveguide.

Claim 9

A voltage-controlled phase shifter comprising a rectangular waveguide for a particular propagation mode, a plurality of switching diodes grouped in successive arrays spaced a quarter wavelength apart to form phase shift sections between diode arrays, said diodes being mounted outside of said waveguide, a plurality of probes, one for each diode, each probe being inserted into said waveguide through a slot and all probes associated with diodes of one array being disposed in a single plane normal to the walls of said waveguide axis, a control voltage terminal outside of said waveguide for receiving selectively forward and reverse bias voltage for each diode, a separate stripline circuit for connecting each diode in series between said terminal and an associated one of said probes, said stripline circuit including a shorted shunt stub next to said associated one of said probes, an open-circuit shunt stub, and a narrow section connecting said shunt stubs to provide an inductance therebetween, and further including coupling sections at each end of said narrow section for connecting said stripline circuit in series between a diode and an associated one of said probes, and a separate capacitor connected between said terminal and said waveguide.

Claim 10

A voltage-controlled phase shifter as defined in claim 6 wherein each array includes 2N diodes, and N is a whole integer.

Claim 11

A voltage-controlled phase shifter as defined in claim 7 wherein N is selected to be the same for every array of switching diodes, except the first and last of said successive arrays, and one less for said first and last arrays.

Claim 12

A voltage-controlled phase shifter as defined in claim 8 in which probes in each plane are disposed to pick up an equal amount of power for said particular propagation mode.

Claim 13

A voltage-controlled phase shifter as defined in claim 9 wherein each stripline circuit is mounted on said waveguide by a housing comprised of two parallel walls of conductive material forming stripline ground planes, and where said shorted shunt stub is connected at its end to said housing.

Claim 14

A voltage-controlled phase shifter as defined in claim 10 wherein each capacitor is mounted on the end of a stripline housing and is connected between a diode and said stripline housing.