A Ku-band dual antenna interference cancellation module

Abstract

The application discloses a Ku frequency band double-antenna interference cancellation module and relates to the field of measurement and control communication.The application comprises a Ku wave band amplitude and phase control module, a Ku wave band coupling module, a Ku wave band detection module and a control module;an omnidirectional antenna is configured to actively collect interference signals;the interference signals are processed in amplitude and phase;and the processed interference signals are added in equal amplitude and opposite phase with interference signals received by a low-sidelobe directional antenna to realize interference cancellation.The interference cancellation module has small insertion loss, high sampling, control and coupling precision, thereby realizing high-precision control of amplitude and phase, making the interference cancellation capability of the whole module extremely high and greatly reducing the adverse effects of interference signals on data link reception signals.

Description

Technical Field

[0001] The present invention relates to the field of measurement, control and communication, and in particular to a Ku-band dual-antenna interference cancellation module. Background Art

[0002] When the ground-to-air data link is operating, the antenna may receive interference signals from the outside world. When the interference signal is outside the receive operating frequency band, the transceiver duplex filter preceding the LNA can suppress it. The degree of suppression depends on the distance between the interference signal and the operating frequency band and the out-of-band suppression capability of the transceiver duplex filter. When the interference signal is within the receive operating frequency band, the transceiver duplexer has no suppression capability. Because the received signal and the interference signal have different frequencies, the received signal is converted to an intermediate frequency signal after frequency conversion. The interference signal has a different frequency from the intermediate frequency after frequency conversion, so the intermediate frequency filter can suppress it. The degree of suppression depends on the distance between the interference signal and the receive frequency and the out-of-band suppression capability of the intermediate frequency filter. When the interference signal is at the same or similar frequency as the receive frequency, neither the duplex filter nor the intermediate frequency filter can suppress the interference signal, which will have a significant impact on the data link, causing noise degradation in the receive link, reduced gain, and decreased receiver sensitivity. Summary of the Invention

[0003] In light of this, the present invention proposes a Ku-band dual-antenna interference cancellation module. This module, combined with low-sidelobe directional antennas and omnidirectional antennas, forms an "asymmetric two-element phased array." This module offers low insertion loss and high precision in signal sampling, control, and synthesis. This significantly reduces the adverse effects of interference on data link reception.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] A Ku-band dual-antenna interference cancellation module, comprising a Ku-band amplitude and phase control module, a Ku-band coupling module, a Ku-band detection module, and a control module;

[0006] The Ku-band amplitude and phase control module receives the spatial interference signal transmitted by the Ku-band omnidirectional antenna, performs corresponding phase and amplitude adjustments, and then sends it to the Ku-band coupling module;

[0007] The Ku-band coupling module receives the spatial interference signal sent by the Ku-band amplitude and phase control module and the working frequency band interference signal sent by the Ku-band low sidelobe directional antenna. The Ku-band coupling module performs interference cancellation and multi-path synthesis on the spatial interference signal and the working frequency band interference signal. The signal after interference cancellation is the output signal of the Ku-band dual-antenna interference cancellation module, and the multi-path synthesized signal is transmitted to the Ku-band detection module.

[0008] The Ku-band detection module receives the multi-channel synthesized signal sent by the Ku-band coupling module, performs detection and outputs it to the control module;

[0009] The control module obtains corresponding phase control voltage and attenuation control voltage according to the multi-channel signals detected by the Ku-band detection module and outputs them to the Ku-band amplitude and phase control module.

[0010] Furthermore, the Ku-band amplitude and phase control module includes an electrically adjustable phase shifter and an electrically adjustable attenuator, the signal input end of the electrically adjustable phase shifter is connected to the Ku-band omnidirectional antenna, the signal output end of the electrically adjustable phase shifter is connected to the signal input port of the electrically adjustable attenuator, and the signal output end of the electrically adjustable attenuator is connected to the Ku-band coupling module; the control interfaces of the electrically adjustable phase shifter and the electrically adjustable attenuator respectively receive the phase control voltage and attenuation control voltage output by the control module.

[0011] Furthermore, the Ku-band coupling module includes a first coupler to a seventh coupler, a first power splitter, and a second power splitter; the first coupler to the seventh coupler each include an input port, a coupling port, and an output port, and the first power splitter and the second power splitter each include an input port and three output ports;

[0012] The input port of the first coupler is connected to the Ku-band low sidelobe directional antenna, the output port of the first coupler is connected to the input port of the third coupler, and the coupling port of the first coupler is connected to the input port of the first power divider;

[0013] The input port of the second coupler is connected to the output port of the electrically adjustable attenuator, the output port of the second coupler is connected to the coupling port of the third coupler, and the coupling port of the second coupler is connected to the input port of the second power divider;

[0014] The output port of the third coupler outputs an output signal after interference cancellation;

[0015] The first output port of the first power divider is connected to the input port of the fifth coupler, the second output port of the first power divider is connected to the input port of the fourth coupler, and the third output port of the first power divider is connected to the input port of the sixth coupler;

[0016] The signal output from the first output port of the second power divider is subjected to a -30 degree phase lag and is then input to the coupling port of the fourth coupler. The second output port of the second power divider is connected to the input port of the seventh coupler. The signal output from the third output port of the second power divider is subjected to a +30 degree phase lead and is then input to the coupling port of the fifth coupler.

[0017] The coupling port of the sixth coupler and the output port of the seventh coupler are both connected to a load.

[0018] Furthermore, the Ku-band detection module includes a first detector to a fourth detector;

[0019] The input port of the first detector is connected to the coupling port of the seventh coupler in the Ku-band coupling module, the input port of the second detector is connected to the output port of the sixth coupler in the Ku-band coupling module, the input port of the third detector is connected to the output port of the fifth coupler in the Ku-band coupling module, and the input port of the fourth detector is connected to the output port of the fourth coupler in the Ku-band coupling module;

[0020] The output ports of the first to fourth detectors output a first amplitude detection voltage, a second amplitude detection voltage, a first phase detection voltage, and a second phase detection voltage, respectively.

[0021] Furthermore, the control module includes a first comparator, a second comparator, a first driver and a second driver;

[0022] The two input ports of the first comparator receive the first amplitude detection voltage and the second amplitude detection voltage of the Ku-band detection module respectively, the output port of the first comparator is connected to the input port of the first driver, and the output port of the first driver is connected to the control port of the electrically adjustable attenuator in the Ku-band amplitude and phase control module;

[0023] The two input ports of the second comparator receive the first phase detection voltage and the second phase detection voltage of the Ku-band detection module respectively; the output port of the second comparator is connected to the input port of the second driver, and the output port of the second driver is connected to the control port of the electrically adjustable phase shifter in the Ku-band amplitude and phase control module;

[0024] When the first amplitude detection voltage is greater than the second amplitude detection voltage, the attenuation control voltage output by the first driver increases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first amplitude detection voltage is less than the second amplitude detection voltage, the attenuation control voltage output by the first driver decreases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first amplitude detection voltage is equal to the second amplitude detection voltage, the attenuation control voltage output by the first driver remains unchanged, and the gain of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged;

[0025] When the first phase detection voltage is greater than the second phase detection voltage, the second driver output phase control voltage increases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first phase detection voltage is less than the second phase detection voltage, the second driver output phase control voltage decreases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first phase detection voltage is equal to the second phase detection voltage, the second driver output phase control voltage remains unchanged, and the phase of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged.

[0026] Compared with the prior art, the application has the beneficial effects that:

[0027] 1、The application constructs a dual-antenna interference cancellation mode through a unique idea, configures an omnidirectional antenna to actively collect interference signals, uses the interference signals, and realizes interference cancellation by adding the interference signals received by a low-sidelobe directional antenna in phase after amplitude processing.

[0028] 2、The application has small insertion loss, high sampling, control and coupling precision of signals, thereby realizing high-precision control of amplitude and phase, greatly reducing the adverse effects of interference signals on data link signals. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 FIG. 1 is a schematic diagram of the overall structure of a Ku-band dual-antenna interference cancellation module according to an embodiment of the application.

[0030] Figure 2 FIG. 2 is a schematic diagram of a Ku-band amplitude and phase control module according to an embodiment of the application.

[0031] Figure 3 FIG. 3 is a schematic diagram of a Ku-band coupling module according to an embodiment of the application.

[0032] Figure 4 FIG. 4 is a schematic diagram of a Ku-band detection module according to an embodiment of the application.

[0033] Figure 5 FIG. 5 is a schematic diagram of a control module according to an embodiment of the application. DETAILED DESCRIPTION

[0034] The application will be further described below in combination with the drawings and specific embodiments.

[0035] A Ku-band dual-antenna interference cancellation module, as shown in FIG. 1, comprises a Ku-band amplitude and phase control module, a Ku-band coupling module, a Ku-band detection module and a control module. Figure 1

[0036] The Ku-band amplitude and phase control module receives spatial interference signals transmitted by a Ku-band omnidirectional antenna, and sends the spatial interference signals to the Ku-band coupling module after corresponding phase and amplitude adjustment.

[0037] The Ku-band coupling module receives the spatial interference signals sent by the Ku-band amplitude and phase control module and the working frequency band interference signals sent by a Ku-band low-sidelobe directional antenna, and performs interference cancellation and multi-channel synthesis on the spatial interference signals and the working frequency band interference signals.The output signal of the Ku-band dual-antenna interference cancellation module is the signal after interference cancellation, and the multi-channel synthesized signal is transmitted to the Ku-band detection module.

[0038] Specifically, in this embodiment, the interference cancellation outputs a signal to a subsequent low noise amplifier (LNA);

[0039] The Ku-band detection module receives the multi-channel synthesized signal sent by the Ku-band coupling module, performs detection and outputs it to the control module;

[0040] The control module obtains corresponding phase control voltage and attenuation control voltage according to the multi-channel signals detected by the Ku-band detection module and outputs them to the Ku-band amplitude and phase control module.

[0041] Furthermore, if Figure 2 As shown, the Ku-band amplitude and phase control module includes an electrically adjustable phase shifter and an electrically adjustable attenuator. The signal input end of the electrically adjustable phase shifter is connected to the Ku-band omnidirectional antenna, the signal output end of the electrically adjustable phase shifter is connected to the signal input port of the electrically adjustable attenuator, and the signal output end of the electrically adjustable attenuator is connected to the Ku-band coupling module. The control interfaces of the electrically adjustable phase shifter and the electrically adjustable attenuator respectively receive the phase control voltage and attenuation control voltage output by the control module.

[0042] Specifically, in this embodiment, the electrically adjustable phase shifter has a phase shift range of 360° and an external control voltage of 0 to 14V. To ensure consistency of external control circuit parameters, the phase shift linearity is 20° / V to 30° / V. The electrically adjustable attenuator has an attenuation range of 30dB and an external control voltage of 0 to 5V. To ensure consistency of external control circuit parameters, the attenuation linearity is 5dB / V to 8dB / V.

[0043] Furthermore, if Figure 3 As shown, the Ku-band coupling module includes a first coupler to a seventh coupler, a first power splitter, and a second power splitter; the first coupler to the seventh coupler each include an input port, a coupling port, and an output port, and the first power splitter and the second power splitter each include an input port and three output ports;

[0044] The input port of the first coupler is connected to the Ku-band low sidelobe directional antenna, the output port of the first coupler is connected to the input port of the third coupler, and the coupling port of the first coupler is connected to the input port of the first power divider;

[0045] The input port of the second coupler is connected to the output port of the electrically adjustable attenuator, the output port of the second coupler is connected to the coupling port of the third coupler, and the coupling port of the second coupler is connected to the input port of the second power divider;

[0046] The output port of the third coupler outputs an output signal after interference cancellation;

[0047] The first output port of the first power divider is connected with an input port of the fifth coupler, the second output port of the first power divider is connected with an input port of the fourth coupler, and the third output port of the first power divider is connected with an input port of the sixth coupler.

[0048] The first output port of the second power divider outputs a signal which is input into a coupled port of the fourth coupler after being phase-shifted by -30 degrees, the second output port of the second power divider is connected with an input port of the seventh coupler, and the third output port of the second power divider outputs a signal which is input into a coupled port of the fifth coupler after being phase-shifted by +30 degrees.

[0049] The coupled port of the sixth coupler and the output port of the seventh coupler are both connected with a load.

[0050] Further, as shown in the figure, the Ku-band detection module includes first to fourth detectors. Figure 4

[0051] The input port of the first detector is connected with the coupled port of the seventh coupler in the Ku-band coupling module, the input port of the second detector is connected with the output port of the sixth coupler in the Ku-band coupling module, the input port of the third detector is connected with the output port of the fifth coupler in the Ku-band coupling module, and the input port of the fourth detector is connected with the output port of the fourth coupler in the Ku-band coupling module.

[0052] The output ports of the first to fourth detectors respectively output first amplitude detection voltage, second amplitude detection voltage, first phase detection voltage and second phase detection voltage.

[0053] Specifically, in the embodiment, the amplitude range of the input signal of the 4-way detector is -60-0 dBm, and the output voltage is 0-5 V. To ensure the normal function of the Ku-band front-end assembly, the output detection voltage of the 4-way detector should have certain consistency when the frequency and amplitude of the input signal are the same. When the amplitude of the input signal is -45-0 dBm, the detection consistency is ±0.5 dB; when the amplitude of the input signal is -60--45 dBm, the detection consistency is ±1.5 dB.

[0054] Further, as shown in the figure, the control module includes first and second comparators, first and second drivers. Figure 5

[0055] The two input ports of the first comparator respectively receive the first and second amplitude detection voltages of the Ku-band detection module, the output port of the first comparator is connected with the input port of the first driver, and the output port of the first driver is connected with the control port of the electrically tunable attenuator in the Ku-band amplitude and phase control module. ​​

[0056] The two input ports of the second comparator receive the first phase detection voltage and the second phase detection voltage of the Ku-band detection module respectively; the output port of the second comparator is connected to the input port of the second driver, and the output port of the second driver is connected to the control port of the electrically adjustable phase shifter in the Ku-band amplitude and phase control module;

[0057] When the first amplitude detection voltage is greater than the second amplitude detection voltage, the attenuation control voltage output by the first driver increases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first amplitude detection voltage is less than the second amplitude detection voltage, the attenuation control voltage output by the first driver decreases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first amplitude detection voltage is equal to the second amplitude detection voltage, the attenuation control voltage output by the first driver remains unchanged, and the gain of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged;

[0058] When the first phase detection voltage is greater than the second phase detection voltage, the second driver output phase control voltage increases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first phase detection voltage is less than the second phase detection voltage, the second driver output phase control voltage decreases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first phase detection voltage is equal to the second phase detection voltage, the second driver output phase control voltage remains unchanged, and the phase of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged.

[0059] The control module cooperates with the Ku-band amplitude and phase control module to realize automatic gain control and automatic phase control of the omnidirectional channel, ensuring that the amplitudes of the omnidirectional signal and the directional signal at the output end of the Ku-band coupling module are equal and the phases are opposite, thus achieving interference cancellation.

[0060] Specifically, in this embodiment, the Ku-band low-sidelobe directional antenna receives an external interference signal at 13 GHz with an amplitude of -25 dBm, which can cause LNA saturation. The Ku-band omnidirectional antenna, whose gain is 20 dB greater than that of the Ku-band low-sidelobe directional antenna, detects an interference signal with an amplitude of -15 dBm. The interference signal received by the Ku-band omnidirectional antenna is sent to the Ku-band amplitude and phase control module. After amplitude and phase adjustment, it is sent to the Ku-band coupling module, where it is coupled and summed with the interference signal from the Ku-band low-sidelobe directional antenna.

[0061] The Ku-band coupling module simultaneously couples and samples the signal, outputting two amplitude sampling signals and two phase sampling signals. The Ku-band detection module detects the four sampling signals and outputs four detection voltages to the monitoring module. The monitoring module processes the four detection voltages and outputs amplitude and phase control voltages to the Ku-band amplitude and phase control module. Finally, after canceling the 13 GHz interference signal, the signal amplitude detected at the LNA input port is -58 dBm, significantly reducing the impact on data link reception.

[0062] In summary, this invention utilizes a unique approach to construct a dual-antenna interference cancellation mode. It deploys omnidirectional antennas to actively collect interference signals. The interference signals, after amplitude and phase processing, are then summed with the interference signals received by the low-sidelobe directional antennas in equal amplitude and anti-phase, achieving interference cancellation. This interference cancellation module features low insertion loss and high signal sampling, control, and coupling accuracy, enabling high-precision control of amplitude and phase. This results in extremely high cancellation capabilities for the entire cancellation module, significantly reducing the adverse effects of interference signals on the data link's received signal.

[0063] Those skilled in the art will appreciate that the embodiments described are intended to help readers understand the principles of the present invention and should be understood that the scope of protection of the present invention is not limited to the embodiments described. It will be apparent to those skilled in the art that various modifications and variations are possible in the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of the present invention.

Claims

1. A Ku-band dual-antenna interference cancellation module, characterized in that: It includes Ku-band amplitude and phase control module, Ku-band coupling module, Ku-band detection module and control module; The Ku-band amplitude and phase control module receives the spatial interference signal transmitted by the Ku-band omnidirectional antenna, performs corresponding phase and amplitude adjustments, and then sends it to the Ku-band coupling module; The Ku-band coupling module receives the spatial interference signal sent by the Ku-band amplitude and phase control module and the working frequency band interference signal sent by the Ku-band low sidelobe directional antenna. The Ku-band coupling module performs interference cancellation and multi-path synthesis on the spatial interference signal and the working frequency band interference signal. The signal after interference cancellation is the output signal of the Ku-band dual-antenna interference cancellation module, and the multi-path synthesized signal is transmitted to the Ku-band detection module. The Ku-band coupling module includes a first coupler to a seventh coupler, a first power splitter, and a second power splitter; the first coupler to the seventh coupler each include an input port, a coupling port, and an output port, and the first power splitter and the second power splitter each include an input port and three output ports; The input port of the first coupler is connected to the Ku-band low sidelobe directional antenna, the output port of the first coupler is connected to the input port of the third coupler, and the coupling port of the first coupler is connected to the input port of the first power divider; The input port of the second coupler is connected to the output port of the electrically adjustable attenuator, the output port of the second coupler is connected to the coupling port of the third coupler, and the coupling port of the second coupler is connected to the input port of the second power divider; The output port of the third coupler outputs an output signal after interference cancellation; The first output port of the first power divider is connected to the input port of the fifth coupler, the second output port of the first power divider is connected to the input port of the fourth coupler, and the third output port of the first power divider is connected to the input port of the sixth coupler; The signal output from the first output port of the second power divider is subjected to a -30 degree phase lag and is then input to the coupling port of the fourth coupler. The second output port of the second power divider is connected to the input port of the seventh coupler. The signal output from the third output port of the second power divider is subjected to a +30 degree phase lead and is then input to the coupling port of the fifth coupler. The coupling port of the sixth coupler and the output port of the seventh coupler are both connected to a load; The Ku-band detection module receives the multi-channel synthesized signal sent by the Ku-band coupling module, performs detection and outputs it to the control module; The control module obtains corresponding phase control voltage and attenuation control voltage according to the multi-channel signals detected by the Ku-band detection module and outputs them to the Ku-band amplitude and phase control module.

2. The Ku-band dual-antenna interference cancellation module according to claim 1, characterized in that: The Ku-band amplitude and phase control module includes an electrically adjustable phase shifter and an electrically adjustable attenuator. The signal input end of the electrically adjustable phase shifter is connected to the Ku-band omnidirectional antenna, the signal output end of the electrically adjustable phase shifter is connected to the signal input port of the electrically adjustable attenuator, and the signal output end of the electrically adjustable attenuator is connected to the Ku-band coupling module. The control interfaces of the electrically adjustable phase shifter and the electrically adjustable attenuator respectively receive the phase control voltage and attenuation control voltage output by the control module.

3. The Ku-band dual-antenna interference cancellation module according to claim 2, wherein: The Ku-band detection module includes a first detector to a fourth detector; The input port of the first detector is connected to the coupling port of the seventh coupler in the Ku-band coupling module, the input port of the second detector is connected to the output port of the sixth coupler in the Ku-band coupling module, the input port of the third detector is connected to the output port of the fifth coupler in the Ku-band coupling module, and the input port of the fourth detector is connected to the output port of the fourth coupler in the Ku-band coupling module; The output ports of the first to fourth detectors output a first amplitude detection voltage, a second amplitude detection voltage, a first phase detection voltage, and a second phase detection voltage, respectively.

4. The Ku-band dual-antenna interference cancellation module according to claim 3, characterized in that: The control module includes a first comparator, a second comparator, a first driver and a second driver; The two input ports of the first comparator receive the first amplitude detection voltage and the second amplitude detection voltage of the Ku-band detection module respectively, the output port of the first comparator is connected to the input port of the first driver, and the output port of the first driver is connected to the control port of the electrically adjustable attenuator in the Ku-band amplitude and phase control module; The two input ports of the second comparator receive the first phase detection voltage and the second phase detection voltage of the Ku-band detection module respectively; the output port of the second comparator is connected to the input port of the second driver, and the output port of the second driver is connected to the control port of the electrically adjustable phase shifter in the Ku-band amplitude and phase control module; When the first amplitude detection voltage is greater than the second amplitude detection voltage, the attenuation control voltage output by the first driver increases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first amplitude detection voltage is less than the second amplitude detection voltage, the attenuation control voltage output by the first driver decreases, and the gain of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first amplitude detection voltage is equal to the second amplitude detection voltage, the attenuation control voltage output by the first driver remains unchanged, and the gain of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged; When the first phase detection voltage is greater than the second phase detection voltage, the second driver output phase control voltage increases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna increases; when the first phase detection voltage is less than the second phase detection voltage, the second driver output phase control voltage decreases, and the phase of the corresponding channel of the Ku-band omnidirectional antenna decreases; when the first phase detection voltage is equal to the second phase detection voltage, the second driver output phase control voltage remains unchanged, and the phase of the corresponding channel of the Ku-band omnidirectional antenna remains unchanged.

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