Low-cost high-isolation sp12t switch

Abstract

The utility model discloses a low -cost high isolation SP12T switch relates to satellite communication field. It includes public coupling amplification unit and signal switching unit, and public coupling amplification unit includes microstrip coupling line directional coupler, first amplifier, equalizer and second amplifier respectively according to signal transmission direction, and signal switching unit is composed of 1 single -pole three -throw switch unit and 3 single -pole four -throw switch unit, wherein, single -pole three -throw switch unit includes SP4T switch chip, and single -pole four -throw switch unit includes 1 SP4T switch chip and 4 SPDT switch chip. The utility model discloses the mode of SP4T switch chip and SPDT switch chip cascade is used to guarantee the channel isolation of switch and on -off isolation, has the characteristics of low cost and high isolation, is especially suitable as the switch module in low -cost high -performance matrix.

Description

Technical Field

[0001] This utility model relates to the field of satellite communication, and in particular to a low-cost, high-isolation SP12T switch, which can be used as a switch module in matrix equipment with stringent requirements for cost and isolation. Background Technology

[0002] In recent years, with the rapid development of satellite communication systems, large satellite communication stations have placed new demands on the isolation and cost of switch matrices. Isolation, in a sense, can be understood as a form of "spurious signal," and poor isolation will affect the communication quality of the signal. The isolation of traditional single-pole multi-throw switches is within 50dB. In terms of cost, the matrix consists of multiple switch modules and power divider modules, with the cost of the switch modules accounting for a large proportion of the overall matrix cost.

[0003] There are two main technical approaches to implementing existing switch modules: one is the PIN diode cascade method, which relies on the number of PIN diodes to ensure isolation, resulting in higher component costs and micro-assembly costs; the other is the "single-pole multi-throw switch + stripline transmission" method, which relies on the stripline in the microwave multilayer board to ensure that signal crosstalk is minimized so that the performance of the single-pole multi-throw switch can be fully utilized, but the blind vias and resin plugs in the microwave multilayer board manufacturing process result in higher costs. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a low-cost, high-isolation SP12T switch. This invention features low cost and high isolation.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A low-cost, high-isolation SP12T switch includes a common coupling amplification unit and a signal switching unit, and has one common signal input port, one coupled signal output port, and twelve signal output ports;

[0007] The common coupling amplification unit includes a microstrip coupled-line directional coupler, a first amplifier, an equalizer, and a second amplifier, respectively, according to the signal transmission direction. The input terminal of the microstrip coupled-line directional coupler is connected to the common signal input port, the coupling terminal is connected to the coupled signal output port, the output terminal is connected to the input terminal of the first amplifier, and the isolation terminal is connected to a 50Ω load. The output terminal of the first amplifier is connected to the input terminal of the equalizer. The output terminal of the equalizer is connected to the input terminal of the second amplifier. The output terminal of the second amplifier is connected to the signal switching unit.

[0008] The signal switching unit consists of one single-pole triple-throw switch unit and three single-pole quadruple-throw switch units; wherein, the single-pole triple-throw switch unit includes an SP4T switch chip, and the single-pole quadruple-throw switch unit includes one SP4T switch chip and four SPDT switch chips.

[0009] In the single-pole triple-throw switch unit, the RFC port of the SP4T switch chip is connected to the output of the second amplifier, the three fixed terminals are connected to the RFC ports of the SP4T switch chips in the three single-pole quad-throw switch units respectively, and the fourth fixed terminal is connected to a 50Ω load.

[0010] In the single-pole four-throw switch unit, the RFC ports of the four SPDT switch chips are connected one-to-one with the four stationary terminals of the SP4T switch chip. The first stationary terminal of the SPDT switch chip is connected to a signal output port, and the second stationary terminal is connected to a 50Ω load.

[0011] Furthermore, it also includes a power supply and control unit, which has one power supply and control port. The power supply and control unit includes a linear voltage regulator circuit and a control circuit. The linear voltage regulator circuit realizes the conversion of the +5V input voltage to the +3.3V voltage. The output of the linear voltage regulator circuit provides the working voltage for each switching chip and the control circuit. The control circuit includes an ARM processor chip. The SP4T switching chip has three control pins, and the SPDT switching chip has one control pin. The 24 pins of the ARM processor chip, PA0 to PA15 and PB0 to PB7, are connected one-to-one with the control pins of the switching chips.

[0012] Furthermore, the microstrip coupling line directional coupler includes a first microstrip line and a second microstrip line. The second microstrip line includes a trunk section. The two ends of the trunk section lead out a coupling port and an isolation port to the same side through 90-degree corners, respectively. The first microstrip line is located on the other side of the trunk section and is arranged parallel to the trunk section of the second microstrip line. The outer corners of the two corners of the second microstrip line are chamfered.

[0013] Furthermore, the first amplifier and the second amplifier are both model IGB-010B-S89, the equalizer is model IEQ-02066, the SP4T switch chip is model ARW3433, and the SPDT switch chip is model ARW3233.

[0014] Furthermore, the common coupling amplification unit and the signal switching unit are located on a single-layer microwave board. The microstrip coupling line directional coupler is implemented through the microstrip line wiring structure of the single-layer microwave board. The first amplifier, equalizer, second amplifier, and each switching chip are surface-mounted on the single-layer microwave board and electrically connected through the microstrip line wiring structure of the single-layer microwave board. The microstrip line of the signal switching unit is in the form of a coplanar waveguide.

[0015] Furthermore, the power supply and control unit is located on a single-layer epoxy board, and the single-layer epoxy board and the single-layer microwave board are connected to corresponding pads by welding enameled wires.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. The technical approach of this utility model is simple, and the unit prices of the switching chips, amplifiers and equalizers involved are all low. Moreover, it does not involve micro-assembly process and multilayer board processing process, so the total cost can be controlled very low.

[0018] 2. This utility model uses the cascaded SP4T switch chip and SPDT switch chip to ensure the channel isolation and switching isolation of the switch.

[0019] 3. This utility model uses a coplanar waveguide microstrip line for signal transmission, which can fully utilize the isolation characteristics of the SP4T switch chip and the SPDT switch chip. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model.

[0021] Figure 2 This is a schematic diagram of the radio frequency section in this utility model.

[0022] Figure 3 This is the board layout diagram of a single-pole four-throw switch unit.

[0023] Figure 4 This is a three-dimensional structural diagram of the present invention.

[0024] Figure 5 This is a schematic diagram of a microstrip coupled-line directional coupler.

[0025] Figure 6 This is the control truth table for the SP4T switch chip.

[0026] Figure 7 This is the control truth table for the SPDT switch chip. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings.

[0028] A low-cost, high-isolation SP12T switch includes a common coupling amplification unit, a signal switching unit, and a power supply and control unit. The switch as a whole has one common signal input port, one coupled signal output port, one power supply and control port, and twelve signal output ports.

[0029] The common coupling amplification unit includes a microstrip coupled-line directional coupler, a first amplifier, a second amplifier, and an equalizer. The input terminal of the microstrip coupled-line directional coupler is connected to the common signal input terminal of the switch, the coupling terminal is connected to the coupled signal output terminal of the switch, the output terminal is connected to the input terminal of the first amplifier, and the isolation terminal is connected to a 50Ω load. The output terminal of the first amplifier is connected to the input terminal of the equalizer. The output terminal of the equalizer is connected to the second amplifier. The output terminal of the second amplifier is connected to the signal switching unit.

[0030] The signal switching unit consists of one single-pole triple-throw (SPTP) switch unit and three single-pole quadruple-throw (SPDT) switch units. The SPTP triple-throw switch unit is composed of SP4T switch chips, with its RFC port connected to the common coupling amplifier unit, RF1-RF3 ports connected to the input terminals of the three SPDT switch units respectively, and RF4 port connected to a 50Ω load. The SPDT quadruple-throw (SPDT) switch unit consists of one SP4T switch chip and four cascaded SPDT switch chips. The RF1-RF4 ports of the SP4T switch chip are connected to the RFC terminals of the four SPDT switch chips respectively, the RF1 port of the SPDT switch chip is connected to the switch signal output terminal, and the RF2 port of the SPDT switch chip is connected to a 50Ω load.

[0031] The SP4T switch chip includes three control pins and five RF pins. The five RF pins are the moving end RFC, the stationary end RF1, the stationary end RF2, the stationary end RF3, and the stationary end RF4, corresponding to five operating states: moving end RFC and stationary end RF1 are on, moving end RFC and stationary end RF2 are on, moving end RFC and stationary end RF3 are on, moving end RFC and stationary end RF4 are on, and all channels are off.

[0032] The SPDT switch chip includes one control pin and three RF pins. The three RF pins are the moving end RFC, the stationary end RF1, and the stationary end RF2, corresponding to two operating states: moving end RFC and stationary end RF1 are turned on, and moving end RFC and stationary end RF2 are turned on. The signal switching unit has a total of 24 control pins across all switch chips.

[0033] The power supply and control unit connects the common coupling amplifier unit and the signal switching unit, and includes a linear regulator circuit and a control circuit. The power supply and control ports use low-frequency connectors to receive external power and control signals. The power signal is transmitted to the linear regulator circuit, and the control signal is transmitted to the control circuit. The linear regulator circuit provides DC power to the SP4T and SPDT switching chips. The control circuit includes an ARM processor chip that sends control commands to the SP4T and SPDT switching chips. For the implementation of the linear regulator circuit, refer to the datasheet of the GED1117ST223_ADJ / 1P8 / 2P5 / 3P3 1A LDO voltage regulator from Beijing Galue Electronics Co., Ltd. For the implementation of the control circuit, refer to the datasheet of the GD32F303xx ARM® Cortex®-M4 32-bit MCU from GigaDevice Semiconductor Inc.

[0034] The common coupling amplification unit is located on a single-layer microwave board, where the microstrip line of the signal switching unit is in the form of a coplanar waveguide. The power supply and control unit is located on a single-layer epoxy board. The single-layer epoxy board and the single-layer microwave board are connected to corresponding pads by soldering enameled wires, so that the 24 pins of the ARM processor chip (PA0-PA15, PB0-PB7) are connected one-to-one with the control pins of the switching chip.

[0035] The external input control signal is a CAN command, containing switching position information from 0 to 12. 0 represents all off, 1 represents switching to output channel 1, and so on, up to 12 representing switching to output channel 12. The ARM processor chip sets the corresponding I / O pin high or low according to the switching position information in the CAN command. The high or low level output of the I / O pin achieves the switching of the switching chip.

[0036] Here is a more specific example:

[0037] A low-cost, high-isolation SP12T switch, such as Figure 1 As shown, the switch includes a common coupling amplification unit 101, a signal switching unit 102, and a power supply and control unit 103. Externally, the switch has one common signal input port A, one coupled signal output port C, one power supply and control port, and twelve signal output ports B. The power supply and control port uses a low-frequency connector; different pins have different definitions. Both the power supply section E and the control section D are located on this interface.

[0038] The input terminal of the common coupling amplifier unit is connected to the common signal input port of the switch, and the output terminal of the common coupling amplifier unit is connected to the input port of the signal switching unit; the output port of the signal switching unit is connected to the output port of the switch; the power supply and control unit provides DC power supply and control signals internally, and receives external power input while communicating with the host computer through the CAN interface.

[0039] like Figure 2 As shown, the radio frequency section mainly consists of a common coupling amplifier unit 101 and a signal switching unit 102.

[0040] The common coupling amplification unit 101 includes a microstrip coupled-line directional coupler, a first amplifier, an equalizer, and a second amplifier.

[0041] The structure of a microstrip coupled-line directional coupler is as follows: Figure 5 As shown, the system includes a first microstrip line and a second microstrip line. The second microstrip line includes a backbone segment. At each end of the backbone segment, a coupling port and an isolation port are led out to the same side via 90-degree bends. The first microstrip line is located on the other side of the backbone segment and is parallel to and side-by-side with the backbone segment of the second microstrip line. Both outer corners of the second microstrip line have chamfers. The widths of the backbone segments, coupling ports, and isolation ports of the first and second microstrip lines are all 1.03 mm. The distance between the coupling ports and the isolation ports is 14.3 mm. The spacing between the first and second microstrip lines is 0.55 mm. The end of the first microstrip line near the coupling port is the input port, and the end near the isolation port is the output port. The width of the output port is 1.08 mm.

[0042] The input terminal of the microstrip coupled-line directional coupler is connected to the common signal input port of the switch, the coupling terminal is connected to the coupled signal output terminal of the switch, the output terminal is connected to the input terminal of the first amplifier, and the isolation terminal is connected to a 50Ω load; the output terminal of the first amplifier is connected to the input terminal of the equalizer; the output terminal of the equalizer is connected to the second amplifier; and the output terminal of the second amplifier is connected to the signal switching unit.

[0043] The signal switching unit 102 consists of one single-pole three-throw (SP4T) switch unit and three single-pole four-throw (SPDT) switch units. The SP4T switch unit is composed of SP4T switch chips, with its RFC port connected to the common coupling amplifier unit, RF1-RF3 ports connected to the input terminals of the three SPDT switch units respectively, and RF4 port connected to a 50Ω load. The SPDT switch unit consists of one cascaded SP4T switch chip and four cascaded SPDT switch chips. The RF1-RF4 ports of the SP4T switch chip are connected to the RFC terminals of the four SPDT switch chips respectively, the RF1 port of the SPDT switch chip is connected to the switch signal output terminal, and the RF2 port of the SPDT switch chip is connected to a 50Ω load. The board layout of the SPDT switch unit is as follows: Figure 3As shown, the radio frequency traces inside the unit are in the form of coplanar waveguides.

[0044] The truth table for SP4T switching chip control is as follows: Figure 6 As shown, the control truth table of the SPDT switch chip is as follows: Figure 7 As shown, in this example, the SPDT switch chip only uses the VCTL pin, while the VEN pin is grounded. The ARM processor chip of the power supply and control unit maps CAN commands to the corresponding pin levels based on the control truth tables of the SP4T and SPDT switch chips.

[0045] like Figure 4 As shown, the three-dimensional structural dimensions of the switch are 124.5mm × 98.9mm × 9.4mm; the output port socket model is SBMA-JFD48, and the output port spacing is 10mm; the input port and coupling port socket models are SSMA-KFD278; and the power supply socket model is JL29-05ZKB. The measured in-band flatness of this switch in the C-band is 1.0dB, and both channel isolation and switching isolation are greater than 80dB.

[0046] This invention employs a cascaded SP4T and SPDT switch chips to ensure both channel isolation and on / off isolation. Furthermore, to fully utilize the isolation characteristics of the SP4T and SPDT switch chips, a coplanar waveguide microstrip line is used for signal transmission. This invention features low cost and high isolation, making it particularly suitable as a switch module in a low-cost, high-performance matrix.

[0047] It should be understood that the above description of specific embodiments of this patent is merely an exemplary description provided to facilitate understanding of the patent solution by those skilled in the art, and does not imply that the scope of protection of this patent is limited to these specific examples. Those skilled in the art, with a full understanding of the technical solution of this patent, can obtain more specific embodiments without any inventive effort by combining technical features, replacing some technical features, adding more technical features, etc., of the various examples listed in this patent. All these specific embodiments are within the scope of the claims of this patent; therefore, these new specific embodiments should also be within the scope of protection of this patent.

Claims

1. A low-cost, high-isolation SP12T switch, characterized in that, It includes a common coupling amplifier unit and a signal switching unit, and has one common signal input port, one coupled signal output port, and 12 signal output ports; The common coupling amplification unit includes a microstrip coupled-line directional coupler, a first amplifier, an equalizer, and a second amplifier, respectively, according to the signal transmission direction. The input terminal of the microstrip coupled-line directional coupler is connected to the common signal input port, the coupling terminal is connected to the coupled signal output port, the output terminal is connected to the input terminal of the first amplifier, and the isolation terminal is connected to a 50Ω load. The output terminal of the first amplifier is connected to the input terminal of the equalizer. The output terminal of the equalizer is connected to the input terminal of the second amplifier. The output terminal of the second amplifier is connected to the signal switching unit. The signal switching unit consists of one single-pole triple-throw switch unit and three single-pole quadruple-throw switch units; wherein, the single-pole triple-throw switch unit includes an SP4T switch chip, and the single-pole quadruple-throw switch unit includes one SP4T switch chip and four SPDT switch chips. In the single-pole triple-throw switch unit, the RFC port of the SP4T switch chip is connected to the output of the second amplifier, the three fixed terminals are connected to the RFC ports of the SP4T switch chips in the three single-pole quad-throw switch units respectively, and the fourth fixed terminal is connected to a 50Ω load. In the single-pole four-throw switch unit, the RFC ports of the four SPDT switch chips are connected one-to-one with the four stationary terminals of the SP4T switch chip. The first stationary terminal of the SPDT switch chip is connected to a signal output port, and the second stationary terminal is connected to a 50Ω load.

2. The low-cost, high-isolation SP12T switch according to claim 1, characterized in that, It also includes a power supply and control unit, which has one power supply and control port. The power supply and control unit includes a linear voltage regulator circuit and a control circuit. The linear voltage regulator circuit realizes the conversion of the +5V input voltage to the +3.3V voltage. The output of the linear voltage regulator circuit provides the working voltage for each switching chip and the control circuit. The control circuit includes an ARM processor chip. The SP4T switching chip has three control pins, and the SPDT switching chip has one control pin. The 24 pins of the ARM processor chip, PA0 to PA15 and PB0 to PB7, are connected one-to-one with the control pins of the switching chips.

3. The low-cost, high-isolation SP12T switch according to claim 1, characterized in that, The microstrip coupling line directional coupler includes a first microstrip line and a second microstrip line. The second microstrip line includes a trunk section. The two ends of the trunk section lead out a coupling port and an isolation port to the same side through 90-degree corners, respectively. The first microstrip line is located on the other side of the trunk section and is arranged parallel to the trunk section of the second microstrip line. The outer corners of the two corners of the second microstrip line are chamfered.

4. The low-cost, high-isolation SP12T switch according to claim 1, characterized in that, The first and second amplifiers are both model IGB-010B-S89, the equalizer is model IEQ-02066, the SP4T switch chip is model ARW3433, and the SPDT switch chip is model ARW3233.

5. The low-cost, high-isolation SP12T switch according to claim 1, characterized in that, The common coupling amplification unit and the signal switching unit are located on a single-layer microwave board. The microstrip coupling line directional coupler is implemented through the microstrip line wiring structure of the single-layer microwave board. The first amplifier, equalizer, second amplifier and each switching chip are surface-mounted on the single-layer microwave board and electrically connected through the microstrip line wiring structure of the single-layer microwave board. The microstrip line of the signal switching unit is in the form of a coplanar waveguide.

6. The low-cost, high-isolation SP12T switch according to claim 5, characterized in that, The power supply and control unit is located on a single-layer epoxy board, and the single-layer epoxy board and the single-layer microwave board are connected to the corresponding pads by welding enameled wire.

Images