A method for reducing electronic noise of a transceiver integrated sonar system by using a nonlinear device

Abstract

The application discloses a method for reducing electronic noise of a transmitting-receiving integrated sonar system by using a nonlinear device, and belongs to the technical field of reducing electronic noise, and comprises the following steps: S1, a transmitter outputs a high-power alternating voltage signal according to a set period and pulse width; S2, a transducer Z1 converts a received alternating voltage signal into an acoustic signal and emits the acoustic signal into water through sound-transmitting rubber of an acoustic array; and S3, during a non-emission period, the acoustic array receives an acoustic reflection signal from a target, the transducer Z1 converts a received acoustic signal into a voltage signal, and the signal is sent to a receiver port IN1 for processing by the receiver, so as to detect and identify a target signal. Two noise signal blocking links mainly composed of two anti-parallel semiconductor diodes are arranged, and the interference of transmitter output noise on the input end of the receiver connected to the transducer at the same time during the non-emission period is more effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of electronic noise reduction technology, and in particular to a method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices, and the method of using it. Background Technology

[0002] For space-constrained devices such as small underwater vehicles and underwater weapons, their sonar systems typically use a shared transducer (i.e., combined transmitter and receiver). During transmission, the transducer is used as the transmitting transducer, and during non-transmission periods, it is used as the receiving transducer. This saves valuable installation space and improves the utilization of space and surface area. For sonar systems using a combined transmitter and receiver transducer, both the transmitter output and receiver input are inevitably connected to the transducer. During non-transmission periods, transmitter noise will inevitably affect the receiver input. In the past, some such devices used single-stage nonlinear devices to block transmitter noise, while others used solid-state relays to short-circuit the transmitter output to ground during non-transmission periods. This invention proposes a scheme using two-stage nonlinear devices to block transmitter noise. Summary of the Invention

[0003] The purpose of this invention is to provide a method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices, and the method of using it, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices, comprising the following steps:

[0005] S1: The transmitter outputs a high-power AC voltage signal according to the set period and pulse width. The AC voltage signal output from the PA1 port of the transmitter is applied to the transducer Z1 through the noise reduction circuit.

[0006] S2: Transducer Z1 converts the received AC voltage signal into an acoustic signal and transmits the sound into the water through the sound-permeable rubber of the acoustic array. During the transmitter's transmission, the receiver's amplification channel IN1 is turned off.

[0007] S3: During non-transmission periods, the acoustic array receives acoustic reflection signals from the target. The transducer Z1 converts the received acoustic signals into voltage signals, which are then sent to the receiver port IN1 for receiver processing to detect and identify the target signals.

[0008] Furthermore, in step S1, the noise reduction circuit includes two sets of anti-parallel semiconductor diodes, a matching transformer T1, a noise absorption resistor R1, and a matching inductor L1, wherein the two sets of anti-parallel semiconductor diodes are composed of semiconductor diodes D1, D2 and semiconductor diodes D3, D4, respectively.

[0009] The PA1 port of the transmitter is connected to one end of the anti-parallel semiconductor diodes D1 and D2, and the other end of the anti-parallel semiconductor diodes D1 and D2 is connected to the primary coil of the matching transformer T1.

[0010] One end of the anti-parallel semiconductor diodes D3 and D4 is connected in parallel with the noise absorption resistor R1 and the secondary coil of the matching transformer T1. The other end of the anti-parallel semiconductor diodes D3 and D4 is connected in series with the matching inductor L1 and the transducer Z1 to the receiver port IN1. The resistor R1 and one end of the transducer Z1 are connected to the secondary coil of the matching transformer T1, and the other end is connected to the ground terminal of the receiver.

[0011] Furthermore, the turns ratio of the primary coil to the secondary coil of the matching transformer T1 is 1:10.

[0012] Furthermore, the two sets of anti-parallel semiconductor diodes have nonlinear current-voltage characteristics. During non-transmission periods, when the transmitter output noise amplitude does not exceed 0.3V, the two sets of anti-parallel semiconductor diodes can block the noise signal.

[0013] Furthermore, the noise absorption resistor R1 is used in conjunction with the anti-parallel semiconductor diodes D1 and D2 to attenuate the noise signal, and the anti-parallel semiconductor diodes D3 and D4 are used for further attenuation of the noise signal under the impedance of the matching inductor L1 and the transducer Z1.

[0014] Furthermore, the current flowing through the anti-parallel semiconductor diodes D3 and D4 is smaller than that of the anti-parallel semiconductor diodes D1 and D2. In order to reduce the influence of the diode junction capacitance, the anti-parallel semiconductor diodes D3 and D4 are selected with a rated current smaller than that of the anti-parallel semiconductor diodes D1 and D2.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] This invention proposes a method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices. A two-stage noise signal blocking circuit, primarily composed of two anti-parallel semiconductor diodes, is installed in the transmission signal transmission path from the transmitter output to the transducer in the combined transceiver sonar system. This reduces the interference of transmitter output noise on the receiver input, and more effectively reduces the interference of transmitter output noise on the receiver input simultaneously connected to the transducer during non-transmission periods. Attached Figure Description

[0017] Figure 1 This is an electrical schematic diagram of an embodiment of the present invention of reducing electronic noise in a sonar system with combined transceiver and receiver transducers using nonlinear devices;

[0018] Figure 2The impedance-mode frequency characteristics of the transducer Z1 of this invention;

[0019] Figure 3 The frequency characteristics of the impedance phase angle of the transducer Z1 in this invention;

[0020] Figure 4 This is the frequency curve showing the effect of transmitter output noise on receiver input when no nonlinear devices are used in this invention;

[0021] Figure 5 The frequency curve showing the effect of transmitter output noise on receiver input in this invention;

[0022] Figure 6 This is a schematic diagram of an embodiment two of the present invention for reducing electronic noise in a sonar system with combined transceiver and receiver transducers using nonlinear devices.

[0023] Figure 7 This is a schematic diagram of the electrical principle of an embodiment of the present invention, which describes a method for reducing electronic noise in a sonar system with combined transceiver and receiver transducers using nonlinear devices. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To address the issue that in existing sonar systems employing combined transmitter and receiver transducers, where both the transmitter output and receiver input are inevitably connected to the transducer, transmitter noise during non-transmission periods inevitably affects the receiver input, previous solutions have employed various methods. Some systems use a single-stage nonlinear device to block transmitter noise, while others use a solid-state relay to short-circuit the transmitter output to ground during non-transmission periods. The following specific implementation examples are provided.

[0026] Example 1:

[0027] Figure 1 The circuit diagram is given. It may be a part of a sonar system with a combined transceiver and receiver. In a sonar system with a combined transceiver and receiver, there may be multiple such circuits. Transmitter represents the transmitter and Receiver represents the receiver.

[0028] Due to various reasons, such as noise from the transmitter power supply and noise from the transmitter circuitry itself, there will always be some unwanted noise at the transmitter output port during non-transmission periods. In a sonar system with a combined transmitter and receiver transducer, this noise is transmitted to the transducer and sent to the receiver input port along with the target signal, reducing the system's signal-to-noise ratio and detection capability.

[0029] A method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices includes the following steps:

[0030] Step 1: The transmitter outputs a high-power AC voltage signal according to the set period and pulse width. The AC voltage signal output from the PA1 port of the transmitter is applied to the transducer Z1 through the noise reduction circuit.

[0031] The noise reduction circuit includes two sets of anti-parallel semiconductor diodes, a matching transformer T1, a noise absorption resistor R1, and a matching inductor L1. The two sets of anti-parallel semiconductor diodes are composed of semiconductor diodes D1 and D2 and semiconductor diodes D3 and D4, respectively.

[0032] The PA1 port of the transmitter is connected to one end of the anti-parallel semiconductor diodes D1 and D2, and the other end of the anti-parallel semiconductor diodes D1 and D2 is connected to the primary coil of the matching transformer T1.

[0033] One end of the anti-parallel semiconductor diodes D3 and D4 is connected in parallel with the noise absorption resistor R1 and the secondary coil of the matching transformer T1. The other end of the anti-parallel semiconductor diodes D3 and D4 is connected in series with the matching inductor L1 and the transducer Z1 to the receiver port IN1. The resistor R1 and one end of the transducer Z1 are connected to the secondary coil of the matching transformer T1, and the other end is connected to the ground terminal of the receiver.

[0034] The turns ratio of the primary coil to the secondary coil of the matching transformer T1 is 1:10.

[0035] The two sets of anti-parallel semiconductor diodes have nonlinear current-voltage characteristics. During non-transmission periods, when the transmitter output noise amplitude does not exceed 0.3V, the two sets of anti-parallel semiconductor diodes can block the noise signal.

[0036] The noise absorption resistor R1 is used in conjunction with the anti-parallel semiconductor diodes D1 and D2 to attenuate the noise signal. The anti-parallel semiconductor diodes D3 and D4 are used for further attenuation of the noise signal under the impedance of the matching inductor L1 and the transducer Z1.

[0037] The current flowing through the anti-parallel semiconductor diodes D3 and D4 is smaller than that of the anti-parallel semiconductor diodes D1 and D2. In order to reduce the influence of the diode junction capacitance, the anti-parallel semiconductor diodes D3 and D4 are selected with a rated current smaller than that of the anti-parallel semiconductor diodes D1 and D2.

[0038] Step 2: Transducer Z1 converts the received AC voltage signal into an acoustic signal and transmits the sound into the water through the acoustically transparent rubber of the acoustic array. During the transmitter's transmission, the receiver's amplification channel IN1 is turned off.

[0039] Step 3: During non-transmission periods, the acoustic array receives acoustic reflection signals from the target. Transducer Z1 converts the received acoustic signals into voltage signals, which are then sent to receiver port IN1 for receiver processing to detect and identify the target signals.

[0040] Figure 2 and Figure 3 The impedance mode and impedance phase angle frequency curves of transducer Z1 are shown. The resonant frequency is 16.218kHz and the impedance mode is 852Ω. The impedance mode is 1.793kΩ at the frequency of 20kHz. The anti-resonant frequency is 24.831kHz and the impedance mode is 3.754kΩ.

[0041] Figure 4 The following is given when no nonlinear devices are used, and the transducer has Figure 2 Under these conditions, the noise response curve of the receiver input to the transmitter output of the sonar system with combined transducers and receivers shows a 19dB amplification at a frequency of 20kHz.

[0042] And the transducer has Figure 2 When characteristics are present, Figure 5 The noise response curves of the receiver input to the transmitter output of the sonar system with combined receiver and transmitter transducers are presented without the use of nonlinear devices. At the 20kHz frequency point, it has amplification of -100.5dB, which is 119.5dB lower than that without the use of nonlinear devices.

[0043] The aforementioned attenuation is only effective for noise signals with small amplitudes. Due to the nonlinear characteristics of semiconductor diodes, they enter the conduction state when the voltage amplitude exceeds 0.7V, resulting in minimal attenuation for transmitted signals of tens of amplitudes.

[0044] In summary, the method of the present invention has a good suppression effect on the electronic noise at the transmitter output of the sonar system with combined transceiver transducers, and can ensure that the normal transmission signal is not affected.

[0045] Example 2:

[0046] Please see Figure 6The PA1 port of the transmitter is connected to one end of the anti-parallel semiconductor diodes D1 and D2. The other end of the anti-parallel semiconductor diodes D1 and D2 is connected in parallel with the anti-parallel semiconductor diodes D3 and D4 and the noise absorption resistor R1. The anti-parallel semiconductor diodes D3 and D4 and the noise absorption resistor R1 are connected to the primary coil of the matching transformer T1.

[0047] The secondary coil of the matching transformer T1 is connected to the matching inductor L1 and the transducer Z1, and the matching inductor L1 and the transducer Z1 are connected in parallel to the receiver port IN1.

[0048] Example 3:

[0049] Please see Figure 7 The PA1 port of the transmitter is connected to the primary coil of the matching transformer T1. The secondary coil of the matching transformer T1 is connected to the anti-parallel semiconductor diodes D1 and D2, the noise absorption resistor R1 and the transducer Z1. The other end of the noise absorption resistor R1 and the anti-parallel semiconductor diodes D1 and D2 is connected to the anti-parallel semiconductor diodes D3 and D4. The anti-parallel semiconductor diodes D3 and D4 are connected in parallel with the matching inductor L1 and the transducer Z1 to the receiver port IN1.

[0050] Embodiments 2 and 3 respectively provide two other circuit configurations of the present invention, both of which employ a noise blocking circuit mainly composed of anti-parallel semiconductor diodes, except that the blocking position on the noise transmission channel (which is also the transmission signal transmission channel) is changed.

[0051] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices, characterized in that, Includes the following steps: S1: The transmitter outputs a high-power AC voltage signal according to the set period and pulse width. The AC voltage signal output from the PA1 port of the transmitter is applied to the transducer Z1 through the noise reduction circuit. S2: Transducer Z1 converts the received AC voltage signal into an acoustic signal and transmits the sound into the water through the sound-permeable rubber of the acoustic array. During the transmitter's transmission, the receiver's amplification channel IN1 is turned off. S3: During non-transmission periods, the acoustic array receives acoustic reflection signals from the target. The transducer Z1 converts the received acoustic signals into voltage signals, which are then sent to the receiver port IN1 for receiver processing to detect and identify the target signals. In step S1, the noise reduction circuit includes two sets of anti-parallel semiconductor diodes, a matching transformer T1, a noise absorption resistor R1, and a matching inductor L1. The two sets of anti-parallel semiconductor diodes are composed of semiconductor diodes D1 and D2 and semiconductor diodes D3 and D4, respectively. The PA1 port of the transmitter is connected to one end of the anti-parallel semiconductor diodes D1 and D2, and the other end of the anti-parallel semiconductor diodes D1 and D2 is connected to the primary coil of the matching transformer T1. One end of the anti-parallel semiconductor diodes D3 and D4 is connected in parallel with the noise absorption resistor R1 and the secondary coil of the matching transformer T1. The other end of the anti-parallel semiconductor diodes D3 and D4 is connected in series with the matching inductor L1 and the transducer Z1 to the receiver port IN1. The resistor R1 and one end of the transducer Z1 are connected to the secondary coil of the matching transformer T1, and the other end is connected to the ground terminal of the receiver. The two sets of anti-parallel semiconductor diodes have nonlinear current-voltage characteristics. During non-transmission periods, when the transmitter output noise amplitude does not exceed 0.3V, the two sets of anti-parallel semiconductor diodes can block the noise signal. The noise absorption resistor R1 is used in conjunction with the anti-parallel semiconductor diodes D1 and D2 to attenuate the noise signal. The anti-parallel semiconductor diodes D3 and D4 are used for further attenuation of the noise signal under the impedance of the matching inductor L1 and the transducer Z1. Without nonlinear devices, the noise response curve of the receiver input to the transmitter output of the sonar system with combined receiver and transmitter transducers has a gain of -100.5dB at the 20kHz frequency point, which is 119.5dB lower than that without nonlinear devices.

2. The method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices as described in claim 1, characterized in that, The turns ratio of the primary coil to the secondary coil of the matching transformer T1 is 1:

10.

3. The method for reducing electronic noise in a combined transceiver sonar system using nonlinear devices as described in claim 1, characterized in that, The current flowing through the anti-parallel semiconductor diodes D3 and D4 is smaller than that of the anti-parallel semiconductor diodes D1 and D2. In order to reduce the influence of the diode junction capacitance, the anti-parallel semiconductor diodes D3 and D4 are selected with a rated current smaller than that of the anti-parallel semiconductor diodes D1 and D2.

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