Coil ringing signal suppression circuit

Abstract

The invention discloses a coil ringing signal suppression circuit, which adopts two capacitors to form a resonant frequency adjusting unit, and forms a resonant circuit under the driving of a driving signal, so that a ringing signal coupling coil is coupled with a magnetic resonance main transmitting coil, and the ringing signal is suppressed. Therefore, suppression of ringing signals in a loop where the magnetic resonance main transmitting coil is located is realized; therefore, compared with a traditional ringing suppression scheme based on an MOS tube, the problem of frequency deviation caused by high voltage resistance and high output capacitance of the MOS tube in the traditional ringing suppression scheme is solved; meanwhile, an energy consumption unit is arranged between the ringing signal coupling coil and the resonant frequency adjusting unit and is used for consuming the energy coupled into the ringing signal coupling coil by the magnetic resonance main transmitting coil, so that the aim of quickly reducing the ringing signal can be fulfilled, and the acquisition efficiency of the magnetic resonance echo signal is improved.

Description

Technical Field

[0001] This invention belongs to the field of magnetic resonance technology, specifically relating to a coil ringing signal suppression circuit. Background Technology

[0002] When a magnetic resonance signal is excited, the circuit containing the main magnetic resonance coil will generate a ringing signal. This ringing signal is related to the operating frequency and the Q value of the coil, as shown in the formula... As shown in the formula (where Vp is the peak voltage of the coil interface and Vn is the coil noise floor), after the transmission pulse ends, the energy stored in the RF main coil needs time to dissipate. The larger the Q value and the lower the frequency, the longer the time required. Therefore, only when the ringing signal is consumed to a level comparable to the coil noise floor can the magnetic resonance echo signal be correctly acquired.

[0003] Based on this, in actual use, it is necessary to suppress the ringing signal. At present, the ringing signal suppression circuit mainly has the following two structures: (1) a ringing consumption circuit based on MOS transistor and output capacitor; (2) a ringing consumption circuit based on one NMOS transistor and one PMOS transistor. However, the aforementioned prior art has the following shortcomings. The ringing consumption circuit in technology (1) is easily limited by the voltage of MOS transistor and the output capacitor. The larger the voltage of MOS transistor, the larger the output capacitor, and the more easily the resonant frequency of the ringing circuit is affected, which will cause frequency shift. Technology (2) also has the same problem because it uses a circuit structure based on MOS transistor. Moreover, none of the above technologies have set up an energy consumption module, which will result in a slow consumption efficiency of the ringing signal, affecting the efficiency of magnetic resonance echo signal acquisition. Therefore, based on the aforementioned shortcomings, how to provide a suppression circuit that is not easy to generate frequency shift and can improve the consumption efficiency of the ringing signal has become an urgent problem to be solved. Summary of the Invention

[0004] The purpose of this invention is to provide a coil ringing signal suppression circuit to solve the problems of frequency shift and slow consumption efficiency of ringing signals in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, a coil ringing signal suppression circuit is provided, comprising:

[0007] A ringing signal coupling coil, wherein the ringing signal coupling coil is coupled to the magnetic resonance main transmitting coil;

[0008] A resonant frequency adjustment unit includes a first capacitor and a second capacitor. One end of the first capacitor and the second capacitor serve as the input terminal of the resonant frequency adjustment unit and are electrically connected to a signal driving unit. The other end of the first capacitor and the second capacitor are electrically connected to the ringing signal coupling coil. This is used to form a resonant circuit under the drive of the driving signal output by the signal driving unit, and to couple the ringing signal coupling coil with the magnetic resonance main transmitting coil. The resonant frequency of the resonant circuit is equal to the resonant frequency of the magnetic resonance main transmitting coil.

[0009] An energy consumption unit is provided, wherein the energy consumption unit is disposed between the ringing signal coupling coil and the resonant frequency adjustment unit, and is used to consume the radio frequency energy coupled from the magnetic resonance main transmitting coil to the ringing signal coupling coil (Ls) to reduce the ringing signal generated by the corresponding circuit of the magnetic resonance main transmitting coil.

[0010] Based on the above disclosure, the coil ringing signal suppression circuit provided by this invention uses two capacitors to form a resonant frequency adjustment unit, and under the drive of an external driving signal, forms a resonant circuit, thereby coupling the ringing signal coupling coil with the magnetic resonance main transmitting coil, and thus suppressing the ringing signal in the circuit where the magnetic resonance main transmitting coil is located. Thus, compared with traditional ringing suppression schemes based on MOSFETs, this invention solves the frequency shift problem caused by the high-voltage, high-output capacitors of MOSFETs used in traditional ringing suppression schemes. Simultaneously, this invention provides an energy consumption unit between the ringing signal coupling coil and the resonant frequency adjustment unit, which consumes the energy coupled from the magnetic resonance main transmitting coil to the ringing signal coupling coil. Based on this, the ringing signal can be rapidly reduced, thereby improving the acquisition efficiency of the magnetic resonance echo signal. Therefore, this invention solves the problems of frequency shift and slow energy consumption efficiency in traditional technologies, and is very suitable for large-scale application and promotion in the field of magnetic resonance technology.

[0011] In one possible design, the energy-consuming unit includes: a first resistor and a second resistor;

[0012] One end of the first resistor is electrically connected to the other end of the first capacitor, and the other end of the first resistor is electrically connected to the ringing signal coupling coil;

[0013] One end of the second resistor is electrically connected to the other end of the second capacitor, and the other end of the second resistor is electrically connected to the ringing signal coupling coil.

[0014] In one possible design, it also includes: a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode;

[0015] The anode of the first rectifier diode is electrically connected to the cathode of the second rectifier diode, and the anode of the third rectifier diode is electrically connected to the cathode of the fourth rectifier diode. The cathode of the first rectifier diode is electrically connected to the cathode of the third rectifier diode, and the anode of the second rectifier diode is electrically connected to the anode of the fourth rectifier diode.

[0016] The common terminal of the first rectifier diode and the second rectifier diode is electrically connected to one end of the ringing signal coupling coil, the common terminal of the third rectifier diode and the fourth rectifier diode is electrically connected to the other end of the ringing signal coupling coil, and the negative terminal of the first rectifier diode and the positive terminal of the second rectifier diode are both electrically connected to the energy consumption unit.

[0017] In one possible design, when the ringing signal generated by the circuit containing the magnetic resonance main transmitting coil is in the positive half-cycle of the signal, the resonant frequency adjustment unit, the energy consumption unit, the first rectifier diode, the ringing signal coupling coil, and the fourth rectifier diode in the coil ringing signal suppression circuit form a circuit;

[0018] When the ringing signal generated by the circuit containing the magnetic resonance main transmitting coil is in the negative half-cycle of the signal, the resonant frequency adjustment unit, the energy consumption unit, the third rectifier diode, the ringing signal coupling coil, and the second rectifier diode in the coil ringing signal suppression circuit form a circuit.

[0019] In one possible design, the first rectifier diode, the second rectifier diode, the third rectifier diode, and the fourth rectifier diode are all PIN diodes.

[0020] In one possible design, it further includes a signal driving unit, wherein the input terminal of the signal driving unit is used to receive an external driving signal, and the output terminal of the signal driving unit is electrically connected to the input terminal of the resonant frequency adjustment unit for transmitting the driving signal to the resonant frequency adjustment unit.

[0021] In one possible design, the signal driving unit includes: a third resistor, a first diode, a second diode, a third capacitor, a first choke inductor, and a second choke inductor;

[0022] One end of the third resistor serves as the input terminal of the signal driving unit, used to receive the driving signal. The other end of the third resistor is electrically connected to the positive terminal of the first diode through the first choke inductor. The negative terminal of the first diode is electrically connected to one end of the second choke inductor. The two ends of the second choke inductor serve as the output terminal of the signal driving unit, and are electrically connected to the input terminal of the resonant frequency adjustment unit.

[0023] The other end of the third resistor is also electrically connected to one end of the third capacitor through the first choke inductor, wherein the other end of the second choke inductor is electrically connected to the positive terminal of the second diode, and the negative terminal of the second diode and the other end of the third capacitor are respectively grounded.

[0024] In one possible design, the magnetic resonance main transmitting coil is also electrically connected to a coil tuning and matching circuit.

[0025] In one possible design, the coil tuning and matching circuit includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, and a power supply;

[0026] The fourth capacitor is connected in parallel across the two ends of the magnetic resonance main transmitting coil. One end of the fourth capacitor is electrically connected to the positive terminal of the power supply through the fifth capacitor, and the other end of the fourth capacitor is electrically connected to the negative terminal of the power supply through the sixth capacitor. The negative terminal of the power supply is grounded.

[0027] Beneficial effects:

[0028] (1) This invention solves the problem of frequency offset caused by the use of high-voltage and high-output capacitors of MOS transistors in traditional ringing suppression schemes; at the same time, this invention sets up an energy consumption unit between the ringing signal coupling coil and the resonant frequency adjustment unit, which is used to consume the energy coupled from the magnetic resonance main transmitting coil to the ringing signal coupling coil. Based on this, the ringing signal can be quickly reduced, thereby improving the acquisition efficiency of the magnetic resonance echo signal; thus, this invention solves the problems of frequency offset and slow energy consumption efficiency in traditional technology, and is very suitable for large-scale application and promotion in the field of magnetic resonance technology.

[0029] (2) The ringing signal suppression circuit provided by the present invention consumes the positive and negative parts of the suppressed ringing signal through two different circuits. Therefore, both circuits resonate at the system frequency under the driving signal and have a low Q value.

[0030] (3) The diodes in the circuit containing the positive and negative parts of the ringing signal are configured back to back, so that they will not be self-conducted through rectification during the radio frequency transmission phase, thus preventing interference with the transmitted radio frequency signal. Attached Figure Description

[0031] Figure 1 A specific circuit diagram of the coil ringing signal suppression circuit provided in the embodiments of the present invention;

[0032] Figure 2 A specific circuit diagram of the circuit corresponding to the magnetic resonance main transmitting coil provided in the embodiments of the present invention;

[0033] Figure 3 A schematic diagram of the path of the driving signal provided in an embodiment of the present invention;

[0034] Figure 4 A schematic diagram of the conduction path in the coil ringing signal suppression circuit when the ringing signal is in the positive half-cycle, provided in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the conduction path in the coil ringing signal suppression circuit when the ringing signal is in the negative half-cycle, as provided in an embodiment of the present invention. Detailed Implementation

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0037] It should be understood that although the terms first, second, etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit, without departing from the scope of the exemplary embodiments of the invention.

[0038] It should be understood that the term "and / or" that may appear in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" that may appear in this document describes another relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this document generally indicates that the related objects before and after it are in an "or" relationship.

[0039] Example:

[0040] See Figures 1-5As shown, the coil ringing signal suppression circuit provided in this embodiment may include, but is not limited to, a ringing signal coupling coil Ls, a resonant frequency adjustment unit, and an energy consumption unit. The ringing signal coupling coil Ls is coupled to the magnetic resonance main transmitting coil Lp, and it works in conjunction with the resonant frequency adjustment unit to suppress the ringing signal in the circuit corresponding to the magnetic resonance main transmitting coil Lp. The energy consumption unit consumes the energy coupled from the magnetic resonance main transmitting coil Lp to the ringing signal coupling coil Ls, thereby achieving a rapid reduction in the ringing signal.

[0041] See Figure 1 As shown, in specific applications, the resonant frequency adjustment unit may include, but is not limited to, a first capacitor C2 and a second capacitor C3; wherein, one end of the first capacitor C2 and the second capacitor C3 serves as the input terminal of the resonant frequency adjustment unit, electrically connected to the signal driving unit, and the other end of the first capacitor C2 and the second capacitor C3 is electrically connected to the ringing signal coupling coil Ls (specifically, the first capacitor C2 and the second capacitor C3 are essentially both electrically connected to the two ends of the ringing signal coupling coil Ls), which is used to form a resonant circuit under the drive signal output by the signal driving unit, and to couple the ringing signal coupling coil Ls with the magnetic resonance main transmitting coil, thereby suppressing the ringing signal in the circuit where the magnetic resonance main transmitting coil Lp is located.

[0042] In this embodiment, the resonant frequency of the ringing signal coupling coil Ls is equal to the resonant frequency of the magnetic resonance main transmitting coil. The resonant frequency of the ringing signal coupling coil Ls is made to be at the resonant frequency of the magnetic resonance main transmitting coil by adjusting the capacitance values ​​of the first capacitor C2 and the second capacitor C3. That is, the resonant frequency of the resonant circuit is at the resonant frequency of the circuit where the magnetic resonance main transmitting coil is located. Of course, the resonant frequency can be adjusted according to the actual use, and is not specifically limited here.

[0043] Meanwhile, this embodiment also provides an energy consumption unit between the ringing signal coupling coil Ls and the resonant frequency adjustment unit. The energy consumption unit is used to consume the energy coupled from the magnetic resonance main transmitting coil to the ringing signal coupling coil Ls, so as to reduce the ringing signal generated by the corresponding circuit of the magnetic resonance main transmitting coil, thereby accelerating the energy consumption and shortening the waiting time for magnetic resonance echo signal acquisition, so as to improve the echo signal acquisition efficiency.

[0044] Therefore, as explained above, this embodiment abandons the traditional MOSFET-based ringing signal suppression scheme and adopts a novel capacitor-based ringing signal suppression scheme. This solves the frequency offset problem caused by the high-voltage, high-output capacitor of the MOSFET in the traditional ringing suppression scheme. At the same time, by setting up an energy consumption unit, the energy in the coil can be consumed quickly, thereby achieving the goal of rapidly reducing the ringing signal. As a result, the waiting time for magnetic resonance echo signal acquisition is shortened, and the acquisition efficiency of the echo signal is improved. Therefore, the suppression circuit provided in this embodiment is very suitable for large-scale application and promotion.

[0045] After explaining the function of the aforementioned main circuit of the suppression circuit, this embodiment provides the specific circuit structure of the main circuit.

[0046] First, see Figure 1 As shown, the following provides one specific circuit configuration for an energy-consuming unit.

[0047] In this embodiment, the energy consumption unit may include, but is not limited to, a first resistor R2 and a second resistor R3; wherein, the connection structure of the aforementioned two resistors with the resonant frequency adjustment unit and the ringing signal coupling coil Ls is as follows:

[0048] See Figure 1 As shown, one end of the first resistor R2 is electrically connected to the other end of the first capacitor C2, and the other end of the first resistor R2 is electrically connected to the ringing signal coupling coil Ls; similarly, one end of the second resistor R3 is electrically connected to the other end of the second capacitor C3, and the other end of the second resistor R3 is electrically connected to the ringing signal coupling coil Ls; thus, the Q value of the resonant circuit can be adjusted by the first resistor R2 and the second resistor R3, and when the entire ringing signal suppression circuit is driven, the ringing signal coupling coil Ls is coupled with the magnetic resonance main transmitting coil Lp, which reduces the Q value of the main transmitting coil and simultaneously couples the energy of the main transmitting coil Lp to the coil Ls, where it is consumed by resistors R2 and R3. Based on this, the purpose of quickly reducing the ringing signal can be achieved.

[0049] Therefore, by using the aforementioned first resistor R2 and second resistor R3, not only can the Q value of the entire circuit be adjusted, but also the energy on the ringing signal coupling coil Ls can be consumed, thereby quickly reducing the ringing signal and shortening the waiting time of the magnetic resonance echo signal.

[0050] Secondly, in this embodiment, the input terminal of the signal driving unit is used to receive external driving signals, and the output terminal of the signal driving unit is electrically connected to the input terminal of the resonant frequency adjustment unit to transmit the driving signal to the resonant frequency adjustment unit so that the resonant frequency adjustment unit forms a resonant circuit, thereby realizing the coupling of the ringing signal coupling coil Ls and the magnetic resonance main transmitting coil Lp.

[0051] Optionally, one specific structure of the disclosed signal driving unit is as follows:

[0052] In this embodiment, the example signal driving unit may include, but is not limited to, a third resistor R1, a first diode D1, a first choke inductor L1, a second choke inductor L2, a second diode D2, and a third capacitor C1; wherein the connection structure of the aforementioned electronic devices is as follows:

[0053] See Figure 3 As shown, one end of the third resistor R1 serves as the input terminal of the signal driving unit, used to receive the driving signal and control the current entering the first diode D1 and the second diode D2; wherein, the other end of the third resistor R1 is electrically connected to the positive terminal of the first diode D1 and one end of the third capacitor C1 through the first choke inductor L1, the negative terminal of the first diode D1 is electrically connected to one end of the second choke inductor L2, the other end of the second choke inductor L2 is electrically connected to the positive terminal of the second diode D2, and the negative terminal of the second diode D2 and the other end of the third capacitor C1 are respectively grounded.

[0054] In this embodiment, the first choke inductor L1 and the second choke inductor L2 are used to suppress the passage of high-frequency signals and allow only the DC drive signal to pass through. When the first diode D1 and the second diode D2 are turned on, they are used together with the aforementioned first capacitor C2, second capacitor C3, first resistor R2 and second resistor R3 to form a coupled resonant circuit (i.e., the aforementioned resonant circuit).

[0055] In practical applications, after the main coil (i.e., coil Lp) transmits an radio frequency signal, a drive signal is immediately applied to the left end of the third resistor R1. The third resistor R1 limits the current magnitude of the drive signal. The drive signal forms a circuit through the third resistor R1, the first choke inductor L1, the first diode D1, the second choke inductor L2, and the second diode D2. A schematic diagram can be found in [reference needed]. Figure 3 As shown; based on this, the two ends of the second choke inductor L2 serve as the output terminals of the signal driving unit and are electrically connected to the input terminals of the resonant frequency adjustment unit (i.e., one end of the second choke inductor L2 is electrically connected to one end of the first capacitor C2, and the other end is electrically connected to one end of the second capacitor C3) to realize signal transmission.

[0056] Meanwhile, it should be noted that the aforementioned signal driving unit essentially restricts the driving signal. When the driving signal is high, it forms a loop through R1, L1, D1, L2, and D2, making D1 and D2 conduct. L1 and L2 act as choke inductors, preventing high-frequency signals from passing through. This prevents high-frequency signals from forming a new loop through L2 or reaching the driving end through L1. L1 and L2 can only allow the driving signal to pass through. Based on this, the signal driving unit of the present invention provides an entry path for the driving signal, thereby facilitating the subsequent formation of a resonant circuit with the first capacitor C2, the second capacitor C3, the first resistor R2, and the second resistor R3.

[0057] Furthermore, this embodiment also includes rectifier diodes at both ends of the ringing signal coupling coil Ls, meaning the coil ringing signal suppression circuit further includes: a first rectifier diode D3, a second rectifier diode D4, a third rectifier diode D5, and a fourth rectifier diode D6; wherein the connection structure of the aforementioned four rectifier diodes is as follows:

[0058] See Figure 1 As shown, the positive terminal of the first rectifier diode D3 is electrically connected to the negative terminal of the second rectifier diode D4, and the positive terminal of the third rectifier diode D5 is electrically connected to the negative terminal of the fourth rectifier diode D6. In this case, the negative terminal of the first rectifier diode D3 is electrically connected to the negative terminal of the third rectifier diode D5, and the positive terminal of the second rectifier diode D4 is electrically connected to the positive terminal of the fourth rectifier diode D6.

[0059] Furthermore, the common terminal of the first rectifier diode D3 and the second rectifier diode D4 is electrically connected to one end of the ringing signal coupling coil Ls, and the common terminal of the third rectifier diode D5 and the fourth rectifier diode D6 is electrically connected to the other end of the ringing signal coupling coil Ls. The negative terminal of the first rectifier diode D3 and the positive terminal of the second rectifier diode D4 are both electrically connected to the energy consumption unit. In this embodiment, the negative terminal of the first rectifier diode D3 is electrically connected to the other end of the first resistor R2, while the positive terminal of the second rectifier diode D3 is electrically connected to the other end of the second resistor R3.

[0060] Therefore, based on the aforementioned circuit description, the specific circuit structure for realizing the resonant circuit is as follows: one end of the first capacitor C2 and the second capacitor C3 is connected to the conducting first diode D1 and the second diode D2, and the other end of the first capacitor C2 and the second capacitor C3 is electrically connected to the ringing signal coupling coil Ls through the first resistor R2, the second resistor R3 and the rectifier diodes D3-D6; thus, a resonant circuit can be formed under the drive of the driving signal, thereby coupling the ringing signal coupling coil Ls with the magnetic resonance main transmitting coil.

[0061] Simultaneously, through the aforementioned four rectifier diodes, different circuits can be formed when the ringing signal is in different signal cycles. That is, when the ringing signal generated by the circuit containing the magnetic resonance main transmitting coil is in the positive half-cycle, the resonant frequency adjustment unit, the energy consumption unit, the first rectifier diode D3, the ringing signal coupling coil Ls, and the fourth rectifier diode D6 in the coil ringing signal suppression circuit form a circuit, the schematic diagram of which can be found in [reference needed]. Figure 4 As shown, that is, through Figure 4 The dashed path in the diagram forms a loop.

[0062] Similarly, when the ringing signal generated by the circuit containing the magnetic resonance main transmitting coil is in the negative half-cycle of the signal, the resonant frequency adjustment unit, the energy consumption unit, the third rectifier diode D5, the ringing signal coupling coil Ls, and the second rectifier diode D4 in the coil ringing signal suppression circuit form a circuit, the schematic diagram of which can be found in [reference needed]. Figure 5 That is, through Figure 5 The dashed path in the diagram forms a loop.

[0063] Based on the aforementioned circuit structure, the positive and negative parts of the ringing signal can be consumed through two different loops, so that both loops resonate at the system frequency and have a low Q value.

[0064] Based on the above, since the positive and negative parts of the ringing signal are consumed through two different circuits, the diodes in the path can be PIN diodes with low junction capacitance and high voltage rating. That is, the four rectifier diodes D3-D6 mentioned above can be PIN diodes with high voltage rating.

[0065] At the same time, from Figure 1 , Figure 4 and Figure 5 As can be clearly seen, the diode circuits of the positive and negative parts are configured back to back. Based on this, the circuit will not self-conduct through rectification during the radio frequency transmission stage, thereby preventing interference with radio frequency transmission and improving circuit stability.

[0066] Finally, this embodiment provides a specific circuit structure for the corresponding loop of the magnetic resonance main transmitting coil, namely, the aforementioned magnetic resonance main transmitting coil Lp is also electrically connected to a coil tuning and matching circuit, wherein the specific structure of this circuit is as follows:

[0067] See Figure 2As shown, the coil tuning and matching circuit described in the example may include, but is not limited to, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, and a power supply; wherein, the fourth capacitor C4 is connected in parallel across the two ends of the magnetic resonance main transmitting coil Lp, one end of the fourth capacitor C4 is electrically connected to the positive terminal of the power supply through the fifth capacitor C5, and the other end of the fourth capacitor C4 is electrically connected to the negative terminal of the power supply through the sixth capacitor C6, and the negative terminal of the power supply is grounded; thus, the aforementioned capacitors C4-C6 serve as coil tuning and matching capacitors, based on which the resonant frequency of the main coil can be adjusted and matched, thereby realizing the excitation of the magnetic resonance signal of the Lp coil.

[0068] Therefore, based on the foregoing explanation, the entire working process of the circuit provided in this embodiment is as follows:

[0069] The first capacitor C2 and the second capacitor C3 will resonate with the ringing signal coupling coil Ls. Therefore, the values ​​of the first capacitor C2 and the second capacitor C3 are first adjusted so that the resonant frequency of the ringing signal coupling coil Ls is located at the resonant frequency of the main transmitting coil. Then, the Q value of the resonant circuit is adjusted through resistors R2 and R3. When the ringing suppression circuit is driven, a resonant circuit can be formed and coupled to Lp through Ls. After coupling, the Q value of the main coil is reduced, and the energy of the main coil Lp is coupled to Ls and consumed through resistors R2 and R3. In this way, the purpose of quickly reducing the ringing signal can be achieved.

[0070] Based on this, the coil ringing signal suppression circuit provided in this embodiment solves the problem of frequency offset caused by the use of high-voltage and high-output capacitors of MOSFETs in conventional ringing suppression schemes. At the same time, it can quickly consume the energy coupled in the coil, thereby shortening the waiting time for echo signal acquisition. Meanwhile, by connecting diodes in reverse series (back-to-back diode arrangement), the signal cannot be rectified and turned on by the diodes during the RF coil transmission stage, thus affecting the transmission efficiency. Therefore, this invention is very suitable for large-scale application and promotion in the field of magnetic resonance.

[0071] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A coil ringing signal suppression circuit, characterized in that, include: A ringing signal coupling coil (Ls) is coupled to the magnetic resonance main transmitting coil. A resonant frequency adjustment unit includes a first capacitor (C2) and a second capacitor (C3). One end of the first capacitor (C2) and the second capacitor (C3) serves as the input terminal of the resonant frequency adjustment unit and is electrically connected to a signal driving unit. The other end of the first capacitor (C2) and the second capacitor (C3) is electrically connected to the ringing signal coupling coil (Ls). This is used to form a resonant circuit under the drive signal output by the signal driving unit, and to couple the ringing signal coupling coil (Ls) with the magnetic resonance main transmitting coil. The resonant frequency of the resonant circuit is equal to the resonant frequency of the magnetic resonance main transmitting coil. An energy consumption unit is provided, wherein the energy consumption unit is disposed between the ringing signal coupling coil (Ls) and the resonant frequency adjustment unit, and is used to consume the radio frequency energy coupled from the magnetic resonance main transmitting coil to the ringing signal coupling coil (Ls) to reduce the ringing signal generated by the corresponding circuit of the magnetic resonance main transmitting coil.

2. The coil ringing signal suppression circuit according to claim 1, characterized in that, The energy consumption unit includes: a first resistor (R2) and a second resistor (R3); One end of the first resistor (R2) is electrically connected to the other end of the first capacitor (C2), and the other end of the first resistor (R2) is electrically connected to the ringing signal coupling coil (Ls); One end of the second resistor (R3) is electrically connected to the other end of the second capacitor (C3), and the other end of the second resistor (R3) is electrically connected to the ringing signal coupling coil (Ls).

3. The coil ringing signal suppression circuit according to claim 1, characterized in that, Also includes: The first rectifier diode (D3), the second rectifier diode (D4), the third rectifier diode (D5), and the fourth rectifier diode (D6); The anode of the first rectifier diode (D3) is electrically connected to the cathode of the second rectifier diode (D4), and the anode of the third rectifier diode (D5) is electrically connected to the cathode of the fourth rectifier diode (D6). The cathode of the first rectifier diode (D3) is electrically connected to the cathode of the third rectifier diode (D5), and the anode of the second rectifier diode (D4) is electrically connected to the anode of the fourth rectifier diode (D6). The common terminal of the first rectifier diode (D3) and the second rectifier diode (D4) is electrically connected to one end of the ringing signal coupling coil (Ls), and the common terminal of the third rectifier diode (D5) and the fourth rectifier diode (D6) is electrically connected to the other end of the ringing signal coupling coil (Ls). The negative terminal of the first rectifier diode (D3) and the positive terminal of the second rectifier diode (D4) are both electrically connected to the energy consumption unit.

4. The coil ringing signal suppression circuit according to claim 3, characterized in that, When the ringing signal generated by the circuit where the magnetic resonance main transmitting coil is located is in the positive half-cycle of the signal, the resonant frequency adjustment unit, the energy consumption unit, the first rectifier diode (D3), the ringing signal coupling coil (Ls) and the fourth rectifier diode (D6) in the coil ringing signal suppression circuit form a circuit; When the ringing signal generated by the circuit containing the magnetic resonance main transmitting coil is in the negative half-cycle of the signal, the resonant frequency adjustment unit, the energy consumption unit, the third rectifier diode (D5), the ringing signal coupling coil (Ls), and the second rectifier diode (D4) in the coil ringing signal suppression circuit form a circuit.

5. A coil ringing signal suppression circuit according to claim 4, characterized in that, The first rectifier diode (D3), the second rectifier diode (D4), the third rectifier diode (D5), and the fourth rectifier diode (D6) are all PIN diodes.

6. The coil ringing signal suppression circuit according to claim 1, characterized in that, The input terminal of the signal driving unit is used to receive external driving signals, and the output terminal of the signal driving unit is electrically connected to the input terminal of the resonant frequency adjustment unit to transmit the driving signals to the resonant frequency adjustment unit.

7. A coil ringing signal suppression circuit according to claim 6, characterized in that, The signal driving unit includes: a third resistor (R1), a first diode (D1), a second diode (D2), a third capacitor (C1), a first choke inductor (L1), and a second choke inductor (L2); One end of the third resistor (R1) serves as the input terminal of the signal driving unit, used to receive the driving signal. The other end of the third resistor (R1) is electrically connected to the positive terminal of the first diode (D1) through the first choke inductor (L1). The negative terminal of the first diode (D1) is electrically connected to one end of the second choke inductor (L2). The two ends of the second choke inductor (L2) serve as the output terminal of the signal driving unit, and are electrically connected to the input terminal of the resonant frequency adjustment unit. The other end of the third resistor (R1) is also electrically connected to one end of the third capacitor (C1) through the first choke inductor (L1). The other end of the second choke inductor (L2) is electrically connected to the positive terminal of the second diode (D2), and the negative terminal of the second diode (D2) and the other end of the third capacitor (C1) are respectively grounded.

8. A coil ringing signal suppression circuit according to claim 1, characterized in that, The magnetic resonance main transmitting coil is also electrically connected to a coil tuning and matching circuit.

9. A coil ringing signal suppression circuit according to claim 8, characterized in that, The coil tuning and matching circuit includes: a fourth capacitor (C4), a fifth capacitor (C5), a sixth capacitor (C6), and a power supply; The fourth capacitor (C4) is connected in parallel across the two ends of the magnetic resonance main transmitting coil. One end of the fourth capacitor (C4) is electrically connected to the positive terminal of the power supply through the fifth capacitor (C5), and the other end of the fourth capacitor (C4) is electrically connected to the negative terminal of the power supply through the sixth capacitor (C6). The negative terminal of the power supply is grounded.

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