JP2000278001A - Flexible microwave switch matrix - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a microwave switch matrix with a simple configuration where signals are highly isolated. SOLUTION: This switch matrix is provided with a plurality of input lines 22 that respectively receive an input signal, a plurality of output lines 26 that output an output signal, and a plurality of nodes 20 each of which connects the input line 22 to a prescribed output line 26. Each node 20 is provided with a switch 30, an input coupler 28 and an output coupler 32. The input coupler 28 connects the input line 24 to the switch 30, the output coupler 32 connects the output line 26 in a way that the switch 30 couples the input line 22 with the output line 26. The input coupler 28, the output coupler 32 and the switch 30 are configured on a printed circuit board with a double side faces to form a plurality of waveguide transmission lines on a same plane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates generally to microwave switch matrices, and more particularly to a flexible planar microwave switch matrix having redundancy.

[0002]

BACKGROUND OF THE INVENTION Microwave and switching devices are generally electronic or electromechanical switches that connect N input signals to selected ones of M output circuits by cables or switchable power splitting / combining devices. Is formed by an array of

Conventional microwave switch matrices are arranged in a three-dimensional array to maintain sufficient separation between input and output signals. The first stage of the array has N circuit boards parallel and spaced apart from each other along a first axis of symmetry that is perpendicular to the circuit boards and penetrates each one of the input circuits. There is one power divider or switch for each. The second stage, the output stage, comprises M circuit boards parallel and spaced from one another along a symmetric second axis perpendicular to the first axis. With such an arrangement, the connections between the circuit boards can maintain a relatively high degree of isolation between the circuits. However, the complexity of such designs has several disadvantages in structure, reliability, footprint and weight.

[0004]

In satellite communication systems, there is an ongoing effort to improve the reliability of communication devices while at the same time reducing the size and weight of system components. Therefore, there is a need for a microwave switch matrix having a high degree of isolation and a simple structure.

In addition to good signal separation, highly reliable systems often require switch matrix redundancy. Many space communication satellites have redundant switch matrices for reliability. Popular redundancy schemes use two separate isolated switch matrices, each switch matrix providing redundant device selection in case of failure. An obvious disadvantage of such a system is that it requires twice as much hardware, ie, electronic devices, switches or passive hybrid devices to provide redundancy. Therefore, another need exists for microwave switch matrices to perform fail-safe operation while reducing the amount of hardware required, thereby eliminating additional power, volume, weight, and complexity. ing.

The present invention is directed to satisfying such needs and providing further related advantages.

[0007]

SUMMARY OF THE INVENTION The present invention provides an improved microwave switch matrix formed in a single plane having a simple configuration that provides high isolation between input and output signals and allows for subdivision. provide. The microwave switch matrix of the present invention includes a plurality of input lines for receiving a plurality of input signals, a plurality of output lines for outputting a plurality of output signals, and any combination of the input lines and the output lines connected at a predetermined time. And a plurality of nodes connecting each of the input lines to each of the output lines. Each of those nodes has a switch, an input coupler, and an output coupler. An input coupler connects the input line to the switch and an output coupler connects the input line to the switch such that the switch couples the input to the output. The nodes of the microwave switch matrix connecting the inputs to the outputs are configured on a double sided circuit board to form a plurality of coplanar waveguide transmission lines.

The microwave switch matrix node of the present invention having the above-described configuration enables any combination of the input line and the output line to be connected at a predetermined time, and at the same time, prevents interference. Gives sufficient signal separation. Various features and advantages of the present invention can be readily understood by the following detailed description with reference to the accompanying drawings.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following detailed description, the terms "left", "right", "up",
"Lower" and the like are used. It should be understood that these terms are used for convenience of describing the embodiments with reference to the drawings. These terms refer to the absolute position and space of any part as “left,” “right,” “up,
It is not specified as "below."

Referring to FIG. 1, there is shown a simplified perspective view of a microwave switch matrix 10 according to the prior art. This switch matrix 10 is plural (M)
(N) input circuit cards connected to the output switches arranged on the output circuit board 14, ie, the input circuit board 12
Contains. The input circuit cards 12 are arranged parallel to one another at equal intervals along the first axis and perpendicular to the first axis. The output circuit boards 14 are also spaced apart and parallel to one another, but they are arranged along a second axis perpendicular to the first axis, and a set of parallel edges of the input circuit board 12. The sections are adjacent to a set of parallel edges of the output circuit board 14, but those edges are perpendicular to one another. With this arrangement, for example, all connections from the top input circuit board can be conducted as an array of connection conductors 16 that are substantially coplanar or parallel to the circuit board itself. These connecting conductors
16 can be connected to the first input port of a switch in output circuit board 14 without the need for two conductors to cross.
Similarly, a second one of the input boards 12 can provide an output without intersecting the first set of connecting conductors from the top input board. The same applies hereinafter. In this way,
The entire switch 10 can be connected without crossing the conductors 16 so that a sufficient degree of isolation can be obtained.

The microwave switch matrix 10 of FIG.
Is referred to as a 6.times.64 switch matrix because it includes 6 input cards 12 (N) with 64 channels each as connected to 64 output circuit boards 14 (M).

A simple schematic configuration of an embodiment of the present invention is shown in FIG. The configuration shown in FIG. 2 requires n to construct a large N × M switch matrix of any size.
A plurality of 4-port interconnect nodes 20 of size xm matrix are used.

Each node 20 includes at least an input coupler 28, a switch module 30, and an output coupler 32. The input coupler 28 connects the signal on the input transmission line 24 to the switch module 30. When the switch module is on, the signal is coupled by the output coupler 32 to the output transmission line 25. The signal is transmitted by the input transmission line 24 on the input port 22, and the output transmission line 25 and the output port 26
Is transmitted via The entire switch matrix is formed by N inputs 22 and M outputs 34.

The signal entering input port 22 travels along a straight transmission line 24 and is terminated with a matched load. In this way, all input ports 22 are always matched. Any input signal received at the input port can be directed to any combination of output ports by input coupler 28, switch module 30, and output coupler 32.

The flexible microwave switch matrix 18 has a flat structure. Through the use of coupler technology and dual sided microwave integrated circuits or stripline structures, the microwave switch matrix can be made simple, flexible and robust.

The planar arrangement of the microwave switch matrix 18 is described with reference to the reference of FIG. The input transmission line 24, input coupler 28 and switch module 30 are formed on the upper side of a double sided radio frequency (RF) circuit board.
The output transmission line 25 and the coupler 32 are formed on the lower side of the RF circuit board. Microwave switch matrix 18 provides equal or taped output levels by adjusting the value of the coupling of input coupler 28 or output coupler 32. Thus, the losses associated with the input coupling can be matched to the losses associated with the output coupling by modifying the design of the coupler. Losses associated with input coupler 28 and output coupler 32 are compensated by input amplifier 36 or output amplifier 38. The bias voltage of the switch module 30 is provided by a distribution board (not shown) located above or below the microwave switch matrix 18.

The switch module 30 can use any switch technology. For example, the switch module 30 includes a FET, a diode, a ferrite switch, a piezoelectric device, an electromechanical switch, or a MEM switch to perform the switching function.

In operation, a distribution board mounted above or below the flexible microwave switch matrix 18 controls the on / off state of the switch 30. For example, assume that the input signal is now at input port 22. The signal now exists at all points along the transmission line 24. Therefore, when the switch module 30 is on, the input signal is transmitted to the output port 26. Similarly, when switch modules 40 and 42 are on, signals are available at each output port 44 and 46.

When switch 42 is off, the input signal along transmission line 24 is still available at any combination of the right or left switch of switch module 42 to transmit the signal at each output port. is there. Therefore, N
Any combination of the input signals at the input ports 22 of M can be transmitted to any combination of the output ports 34 of M. By constructing a sub-matrix of four-port interconnect nodes 20, a large N × M switch matrix of any size can be constructed.

In order to maintain the separation of the input signal from the output signal, the microwave switch matrix of the present invention preferably employs a double sided RF using a coplanar waveguide transmission line technology as shown in FIG. (Radio frequency) is formed in a circuit board.

As shown in FIG. 3, transmission line crossings occur on the opposite side of the circuit board. The input signal is separated from the output signal by a plurality of holes 50 plated with a conductive metal material connected to each ground plane on which the transmission line resides. The coplanar waveguide transmission line layout of the microwave switch matrix provides uniform microwave grounding with signal separation. This allows for a flexible, planar, single substrate structure of the microwave switch matrix. This configuration can be extended to the highest N × M matrix.

As a result of the flexible and scalable nature of the present microwave switch matrix, redundancy can be provided by adding extra input and output ports and connecting them via nodes.

As shown in FIG. 4, ring redundancy can be provided by adding input and output ports and connecting through switch modules. For example, signal input 60 is input coupler 66 and output coupler
Output line by switch module 64 in relation to 68
62 can be combined. Output line to provide redundant signal
62 is connected to input 70 and further assembles the original signal received by input 60 which is also available at any output coupled to input 70. Additional or alternative redundancy can be achieved by coupling input signal 60 to output 72 by switch module 74. The same signal is now at inputs 60 and 70 and outputs 62 and 72 and output
Combining 72 to input 76 provides additional redundancy.

From the above description, it is not conventional non-planar,
A new and improved technique of a flexible microwave switch matrix that overcomes the shortcomings of cabled microwave switch matrices has been demonstrated.

Although specific embodiments have been shown, it will be understood that the invention is not limited to the above description, since the above description is capable of many modifications by those skilled in the art. Accordingly, such alternatives, modifications and equivalents are included within the scope of the claims of the present invention.

[Brief description of the drawings]

FIG. 1 is a simplified perspective view of a microwave switch matrix according to the prior art.

FIG. 2 is a schematic diagram of a flexible microwave switch matrix of one embodiment of the present invention.

FIG. 3 is a plan view of an exemplary layout of a common plane waveguide transmission line of one embodiment of the present invention.

FIG. 4 is a schematic diagram of a flexible microwave switch matrix of another embodiment of the present invention.

Claims (24)

[Claims] 1. A plurality of input lines for receiving a plurality of input signals, a plurality of output lines for outputting a plurality of output signals, and an arbitrary combination of the input lines and the output lines are connected at a predetermined time. And a plurality of nodes connecting each of the input lines to each of the output lines, each of the nodes comprising a switch, an input coupler, and an output coupler, wherein the switch connects the input line. The input coupler connects the input line to the switch, the output coupler connects the switch to the output line, and the input coupler, the output coupler, and the switch to couple to the output line. Wherein the planar microphone is formed on a double-sided circuit board to form a plurality of coplanar waveguide transmission lines. Wave switch matrix. 2. The input coupler, the output coupler,
The planar microwave switch matrix of claim 1, wherein said switches are configured on a double sided circuit board using a microwave integrated circuit architecture. 3. The input coupler, the output coupler,
The switch is configured on a double sided circuit board using a stripline architecture.
A planar microwave switch matrix as described. 4. The input coupler and the output coupler,
2. The planar microwave switch matrix of claim 1 having equal coupling values. 5. The input coupler and the output coupler,
2. The planar microwave switch matrix of claim 1, wherein said matrix has different coupling values. 6. The switch matrix of claim 1, wherein the signal input line comprises an input amplifier for compensating signal attenuation associated with the input coupler and the switch. 7. The switch matrix of claim 1, wherein the output line comprises an output amplifier for compensating signal attenuation associated with the output coupler and the switch. 8. The planar microwave switch matrix according to claim 1, wherein said switch comprises a field effect transistor. 9. The planar microwave switch matrix of claim 1, wherein said switch comprises a diode switch. 10. The planar microwave switch matrix of claim 1, wherein said switch comprises a piezoelectric switch. 11. The planar microwave switch matrix according to claim 1, wherein said switch comprises an electromechanical switch. 12. The planar microwave switch matrix according to claim 1, wherein said switch comprises a ferrite switch. 13. The planar microwave switch matrix of claim 1, wherein said switch comprises a micro-machined electrochemical switch. 14. An N × M planar microwave switch matrix configured on a substrate having circuit boards on both sides, wherein at least one input line is formed on the circuit board on a first side of the substrate. And a plurality of nxm interconnect modules commonly connected to one or more output lines formed on a circuit board on a second side of the substrate, wherein any combination of input and output lines is provided. Are connected at a predetermined time, wherein each of the interconnect modules is connected to one or more switch modules formed on a circuit board on a first side surface of the substrate and the input line to the switch modules. One or more input couplers, and one or more outputs formed on a circuit board on a second side of the board and connecting the switch module to the output lines. And the input line, the output line, the input coupler, and the output coupler constitute a coplanar waveguide transmission line on a substrate provided with a circuit board on both sides. A planar microwave switch matrix, characterized in that: 15. The planar microwave switch matrix of claim 14, wherein said input coupler and said output coupler have equal coupling values. 16. The planar microwave switch matrix of claim 14, wherein said input coupler and said output coupler have different coupling values. 17. The switch matrix according to claim 14, wherein said input line comprises an input amplifier for compensating signal attenuation associated with said input coupler and said switch. 18. The switch matrix according to claim 14, wherein the output line comprises an output amplifier to compensate for signal attenuation associated with the output coupler and the switch. 19. The matrix of claim 14, wherein said switch comprises a field effect transistor. 20. The matrix of claim 14, wherein the switch comprises a diode switch. 21. The planar microwave switch matrix of claim 14, wherein said switch comprises a piezoelectric switch. 22. The planar microwave switch matrix according to claim 14, wherein said switch comprises an electromechanical switch. 23. The planar microwave switch matrix according to claim 14, wherein said switch comprises a ferrite switch. 24. The planar microwave switch matrix of claim 14, wherein said switch comprises a micro-machined electrochemical switch.