RF MEMS switch loop 180° phase bit radiator circuit
First Claim
Patent Images
1. A switched loop RF radiator circuit, comprising:
- a radiator element;
a circuit RF input/output (I/O) port;
a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having first and second transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs, wherein said switch circuit includes first and second single-pole-single-throw (SPST) MEM switch circuits;
wherein a first pole of said first MEM switch circuit is connected to a first transmission line, a second pole of said first MEM switch circuit is connected to the first transmission line leg, a first pole of said second MEM switch is connected to a second transmission line, and a second pole of the second MEM switch circuit is connected to the second transmission line leg, the first and second transmission lines connected together at a junction and coupled to the I/O port;
wherein in a first circuit phase state, the first MEM switch is set to a closed state, and the second MEM switch is set to an open state, and in a second phase state mode the first MEM switch is set to an open state and the second MEM switch is set to a closed state to provide a 180°
phase difference from the first phase state; and
wherein in a reflective state, the first and second MEM switches are both set to the closed state to reflect incident RF energy.
2 Assignments
0 Petitions
Accused Products
Abstract
A switched loop RF radiator circuit, comprising a radiator element, a RF input/output (I/O) port, and a balun coupled between the radiator element and the (I/O) port. The balun includes a 180° switched loop circuit having transmission line legs coupled to a balun transition to provide a selectable phase shift, and a microelectromechanically machined (MEM) switch Many radiator circuits can be deployed in an electronically scanned antenna array.
34 Citations
20 Claims
-
1. A switched loop RF radiator circuit, comprising:
-
a radiator element;
a circuit RF input/output (I/O) port;
a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having first and second transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs, wherein said switch circuit includes first and second single-pole-single-throw (SPST) MEM switch circuits;
wherein a first pole of said first MEM switch circuit is connected to a first transmission line, a second pole of said first MEM switch circuit is connected to the first transmission line leg, a first pole of said second MEM switch is connected to a second transmission line, and a second pole of the second MEM switch circuit is connected to the second transmission line leg, the first and second transmission lines connected together at a junction and coupled to the I/O port;
wherein in a first circuit phase state, the first MEM switch is set to a closed state, and the second MEM switch is set to an open state, and in a second phase state mode the first MEM switch is set to an open state and the second MEM switch is set to a closed state to provide a 180°
phase difference from the first phase state; and
wherein in a reflective state, the first and second MEM switches are both set to the closed state to reflect incident RF energy. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
a primary transmission line coupled between the MEM switch circuit and the RF I/O port;
a secondary transmission line coupled between the MEM switch circuit and a secondary RF I/O port;
the MEM switch circuit includes a first SPDT MEM switch circuit connected between said first transmission line leg, said primary transmission line and said secondary transmission line, and a second SPDT MEM switch circuit connected between said second transmission line leg, said primary transmission line and said secondary transmission line;
wherein the first SPDT switch circuit selectively connects the first transmission line leg to the primary transmission line or to the secondary transmission line, the first SPDT switch circuit further having an open circuit state, and the second SPDT switch circuit selectively connects the second transmission line leg to the primary transmission line or to a matched load termination, the second SPDT switch circuit further having an open circuit state.
-
-
9. The circuit of claim 1, wherein said MEM switch circuit comprises MEM metal-metal contact switches.
-
10. The circuit of claim 9, wherein said radiator element, said balun and said MEM switch circuit are all fabricated on a common dielectric substrate.
-
11. An electronically scanned array, comprising:
-
a linear array of radiator circuits, each circuit including a radiator element, a circuit RF input/output (I/O) port, a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having two transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs, wherein for each radiator circuit, the switch circuit includes first and second single-pole-single-throw (SPST) MEM switch circuits, and wherein a first pole of said first MEM switch circuit is connected to a first transmission line, a second pole of said first MEM switch circuit is connected to the first transmission line leg, a first pole of said second MEM switch is connected to a second transmission line, and a second pole of the second MEM switch circuit is connected to the second transmission line leg, the first and second transmission liens connected together at a junction and coupled to the I/O port;
an array of phase shifters coupled to the I/O ports of the radiator circuits;
an RF manifold including a plurality of phase shifter ports respectively coupled to a corresponding phase shifter RF port and an RF port;
an array controller for providing control signals to the phase shifters to control the phase shift setting of the array of the phase shifters and to the MEM switch circuits;
wherein in a first array phase state, for each radiator circuit, the first MEM switch is set to a closed state, and the second MEM switch is set to an open state, and in a second phase state mode the first MEM switch is set to an open state and the second MEM switch is set to a closed state to provide a 180°
phase difference from the first phase state; and
wherein in a reflective state, the first and second MEM switches of each radiator circuit are both set to the closed state to reflect incident RF energy. - View Dependent Claims (12, 13, 14, 15, 16)
a primary transmission line coupled between the MEM switch circuit and the RF I/O port;
a secondary transmission line coupled between the MEM switch circuit and a secondary RF I/O port;
the MEM switch circuit includes a first SPDT MEM switch circuit connected between said first transmission line leg, said primary transmission line and said secondary transmission line, and a second SPDT MEM switch circuit connected between said second transmission line leg, said primary transmission line and said secondary transmission line;
wherein the first SPDT switch circuit selectively connects the first transmission line leg to the primary transmission line or to the secondary transmission line, the first SPDT switch circuit further having an open circuit state, and the second SPDT switch circuit selectively connects the second transmission line leg to the primary transmission line or to a matched load termination, the second SPDT switch circuit further having an open circuit state.
-
-
17. A switched loop RF radiator circuit, comprising:
-
a radiator element;
a circuit RF input/output (I/O) port;
a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having first and second transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs, wherein the first and second transmission line legs each have an effective electrical length of one quarter wavelength at an operating signal for the circuit and wherein the switch circuit includes a single-pole-double-throw (SPDT) MEM switch circuit;
wherein a first pole of said SPDT MEM switch circuit is connected to the first transmission line leg, a second pole of the SPDT MEM switch circuit is connected to the second transmission line leg, and a third pole of the SPDT switch circuit is coupled to the I/O port; and
wherein said SPDT MEM switch circuit has first, second and third switch states, said first state wherein said first pole is connected to said third pole and said second pole is isolated from said third pole, said second state wherein said second pole is connected to said third pole and said first pole is isolated from said third pole, and said third state wherein both said first pole and said second pole are isolated from the third pole. - View Dependent Claims (18)
-
-
19. A switched loop RF radiator circuit, comprising:
-
a radiator element;
a circuit RF input/output (I/O) port;
a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having first and second transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs;
a primary transmission line coupled between the MEM switch circuit and the RF I/O port;
a secondary transmission line coupled between the MEM switch circuit and a secondary RF I/O port; and
the MEM switch circuit includes a first SPDT MEM switch circuit connected between said first transmission line leg, said primary transmission line and said secondary transmission line, and a second SPDT MEM switch circuit connected between said second transmission line leg, said primary transmission line and said secondary transmission line;
wherein the first SPDT switch circuit selectively connects the first transmission line leg to the primary transmission line or to the secondary transmission line, the first SPDT switch circuit further having an open circuit state, and the second SPDT switch circuit selectively connects the second transmission line leg to the primary transmission line or to a matched load termination, the second SPDT switch circuit further having an open circuit state.
-
-
20. An electronically scanned array, comprising:
-
a linear array of radiator circuits, each circuit including a radiator element, a circuit RF input/output (I/O) port, a balun coupled between the radiator element and the I/O port, the balun including a 180°
switched loop circuit having two transmission line legs coupled to a balun transition to provide a selectable 180°
phase shift, and a microelectromechanically machined (MEM) switch circuit to select one of said transmission line legs;
an array of phase shifters coupled to the I/O ports of the radiator circuits;
an RF manifold including a plurality of phase shifter ports respectively coupled to a corresponding phase shifter RF port and an RF port;
an array controller for providing control signals to the phase shifters to control the phase shift setting of the array of the phase shifters and to the MEM switch circuits;
a primary transmission line coupled between the MEM switch circuit and the RF I/O port;
a secondary transmission line coupled between the MEM switch circuit and a secondary RF I/O port; and
the MEM switch circuit includes a first SPDT MEM switch circuit connected between said first transmission line leg, said primary transmission line and said secondary transmission line, and a second SPDT MEM switch circuit connected between said second transmission line leg, said primary transmission line and a said secondary transmission line;
wherein the first SPDT switch circuit selectively connects the first transmission line leg to the primary transmission line or to the secondary transmission line, the first SPDT switch circuit further having an open circuit state, and the second SPDT switch circuit selectively connects the second transmission line leg to the primary transmission line or to a matched load termination, the second SPDT switch circuit further having an open circuit state.
-
Specification