Bluetooth earphone and electromagnetic interference simulation analysis method and current sound elimination method thereof

Abstract

The application relates to the earphone technical field and discloses a Bluetooth earphone and an electromagnetic interference simulation analysis method and a current sound elimination method thereof.The simulation analysis method comprises the following steps: when the Bluetooth earphone releases a Bluetooth signal, measuring total magnetic field distribution information generated by at least one target component in a magnetic isolation box; estimating magnetic force distribution information in the magnetic isolation box according to the total magnetic field distribution information; exerting force on virtual iron filings distributed in the magnetic isolation box according to the magnetic force distribution information, so that the virtual iron filings adaptively move under the magnetic force action at each measuring position; and generating a three-dimensional magnetic field distribution map according to the movement and distribution state of the virtual iron filings.The application realizes simulation of the internal magnetic field of the Bluetooth earphone, and based on the three-dimensional magnetic field distribution map, a staff member can intuitively see the magnetic field conditions of each region, and then corresponding effective measures are taken to eliminate the magnetic field in the region with a relatively strong magnetic field, so that current sound is eliminated and the sound quality is improved.

Description

Technical Field

[0001] This invention relates to the field of headphone technology, and in particular to a Bluetooth headphone and its electromagnetic interference simulation analysis method and current noise cancellation method. Background Technology

[0002] In recent years, Bluetooth headphones have emerged and developed rapidly, and users have increasingly higher requirements for the sound quality of Bluetooth headphones. However, Bluetooth headphones on the market often produce electrical noises such as "pop" and "hiss" during use, which affects the user's listening experience. This requires solving such problems from both the hardware and software levels.

[0003] This is because: during playback, Bluetooth headphones need to release Bluetooth signals every 1.25ms, which manifests as excessive current pumping on the circuit board, causing changes in the electric field and thus generating a changing magnetic field. At the same time, due to the small size of Bluetooth headphones and the complex internal electromagnetic field relationships, including the speaker, magnet, battery, and motherboard with power inductors and wires, the changes in the magnetic field generated by these components when the current changes can easily couple to the speaker of the Bluetooth headphones, causing the audio played by the speaker to carry current noise and affecting the sound quality.

[0004] Therefore, if the distribution of the internal magnetic field of Bluetooth headphones is known, the magnetic field can be weakened or even canceled in the early design process to eliminate current noise. However, there is currently no solution on the market that can simulate the internal magnetic field of Bluetooth headphones. Summary of the Invention

[0005] The purpose of this invention is to provide a Bluetooth headset and its electromagnetic interference simulation analysis method and current noise cancellation method, so as to realize the simulation of the internal magnetic field of the Bluetooth headset, effectively eliminate current noise, and improve sound quality.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] An electromagnetic interference simulation analysis method for a Bluetooth headset, wherein the Bluetooth headset includes multiple target components that generate magnetic fields when powered on, and each of the target components is assembled according to a preset layout; the electromagnetic interference simulation analysis method includes:

[0008] When the Bluetooth headset releases a Bluetooth signal, the total magnetic field distribution information generated by at least one of the target components in the magnetic shielding box is measured. The total magnetic field distribution information includes the magnetic field strength and magnetic field direction at multiple measurement locations in the magnetic shielding box.

[0009] The magnetic force distribution information inside the magnetic shielding box is estimated based on the total magnetic field distribution information. The magnetic force distribution information includes the magnitude and direction of the magnetic force at each measurement location inside the magnetic shielding box.

[0010] According to the magnetic force distribution information, a force is applied to the virtual iron filings distributed in the magnetic shielding box, so that the virtual iron filings move adaptively under the magnetic force at each measurement position;

[0011] A three-dimensional magnetic field distribution map is generated based on the movement and distribution of the virtual iron filings.

[0012] Optionally, it also includes: classifying and identifying strong magnetic field regions and weak magnetic field regions in the three-dimensional magnetic field distribution map, and labeling the magnetic field strength and magnetic field direction corresponding to the strong magnetic field regions.

[0013] Optionally, measuring the total magnetic field distribution information generated by at least one of the target components within the magnetic shielding box includes:

[0014] For each target component, the magnetic field distribution is measured separately: the current target component is placed inside the magnetic shielding box, and other target components are placed outside the magnetic shielding box; when the Bluetooth headset releases the Bluetooth signal, the individual magnetic field distribution information generated by the current target component inside the magnetic shielding box is measured.

[0015] By superimposing the individual magnetic field distribution information corresponding to each target component, the total magnetic field distribution information generated by all target components in the magnetic isolation box is obtained.

[0016] Optionally, in the step of measuring the magnetic field distribution,

[0017] For a target component that generates a changing magnetic field, the distribution information of a single magnetic field generated by the current target component in the magnetic isolation box is measured according to the Biot-Savart theorem and the right-hand screw rule.

[0018] For a target component that generates a constant magnetic field, a magnetic field strength measuring instrument is used to measure the distribution information of a single magnetic field generated by the current target component within the magnetic isolation box.

[0019] Optionally, the target component may be a power inductor, a wire, a battery, a horn, or a magnet.

[0020] A method for eliminating electrical noise includes:

[0021] Based on the electromagnetic interference simulation analysis method for Bluetooth headsets, a three-dimensional magnetic field distribution map of the Bluetooth headset under the current layout is generated.

[0022] Based on the magnetic field distribution of the strong magnetic field region in the three-dimensional magnetic field distribution map, the component layout of the Bluetooth headset is adjusted to weaken the magnetic field in the strong magnetic field region; and / or, a demagnetizing unit is added to the Bluetooth headset to cancel the magnetic field in the strong magnetic field region.

[0023] Optionally, the target component is a battery;

[0024] The addition of a demagnetizing unit in the Bluetooth headset specifically includes: winding a first wire around the battery terminals, wherein the current direction of the first wire is opposite to the current direction of the terminals, so that the magnetic field generated by the first wire is opposite to the magnetic field generated by the terminals.

[0025] Optionally, the target component is a power inductor;

[0026] The addition of a demagnetizing unit in the Bluetooth headset specifically includes: adding a second trace on the motherboard in the adjacent area of ​​the power inductor, wherein the current direction of the second trace is opposite to the current direction of the power inductor, so that the magnetic field generated by the second trace is opposite to the magnetic field generated by the power inductor.

[0027] A Bluetooth headset, wherein the Bluetooth headset is manufactured according to any one of the above-described current noise cancellation methods.

[0028] An electromagnetic interference simulation and analysis device for Bluetooth headsets, comprising a memory and a processor;

[0029] The memory is used to store instructions;

[0030] The processor is used to execute the instructions in the memory to implement the electromagnetic interference simulation analysis method for Bluetooth headsets described in any of the above-mentioned methods.

[0031] A storage medium storing a plurality of instructions adapted for loading by a processor to execute the steps in the electromagnetic interference simulation analysis method for Bluetooth headsets described above.

[0032] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0033] This invention first measures the magnetic field distribution information of the Bluetooth headset inside the magnetic shielding box, then estimates the magnetic force distribution information inside the box based on this information. Next, it controls the virtual iron filings inside the box to undergo adaptive motion according to this magnetic force distribution information. Finally, it generates a three-dimensional magnetic field distribution map based on the motion and distribution of the virtual iron filings, thus simulating the internal magnetic field of the Bluetooth headset. Based on this three-dimensional magnetic field distribution map, staff can intuitively see the magnetic field conditions in each area and then take appropriate and effective measures to cancel the magnetic field in areas with stronger magnetic fields, thereby eliminating current noise and improving sound quality. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are 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.

[0035] Figure 1 A flowchart of an electromagnetic interference simulation analysis method for Bluetooth headsets provided in an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of an electromagnetic interference simulation analysis method for Bluetooth headsets provided in an embodiment of the present invention.

[0037] Figure 3 This is a schematic diagram of the single magnetic force at point P in a magnetic shielding box provided in an embodiment of the present invention.

[0038] Figure 4 This is a schematic diagram of the superposition of multiple magnetic fields at point P in a magnetic shielding box provided in an embodiment of the present invention.

[0039] Figure 5 A flowchart of a Bluetooth headset noise cancellation method provided in an embodiment of the present invention.

[0040] Figure 6 This is a schematic diagram illustrating the use of wires wound around the battery tabs to counteract a strong magnetic field, as provided in an embodiment of the present invention.

[0041] Figure 7 This is a schematic diagram illustrating the addition of traces at the power inductor to counteract a strong magnetic field, as provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] Example 1

[0044] Please see Figure 1 and Figure 2 This invention provides a method for simulating and analyzing electromagnetic interference in Bluetooth headsets, including:

[0045] Step 101: When the Bluetooth headset releases a Bluetooth signal, measure the total magnetic field distribution information generated by at least one target component in the magnetic shielding box. The total magnetic field distribution information includes the magnetic field strength and magnetic field direction at multiple measurement locations in the magnetic shielding box.

[0046] It should be noted that the target component in this embodiment refers to a component that generates a magnetic field when powered on. Furthermore, according to the type of magnetic field generated, the target component can be divided into two categories: the first category is components that can generate a changing magnetic field with a changing electric field, such as batteries, power inductors and wires arranged on a motherboard; the second category is components that generate a constant magnetic field, such as speakers and magnets usually mounted on headphone cases.

[0047] The magnetic shielding box provides a theoretically enclosed testing space that can shield external magnetic fields to ensure the accuracy of measurement results.

[0048] Since the Bluetooth headset releases a Bluetooth signal every 1.25ms, the test result in the magnetic shielding box is that the 800Hz frequency doubling will produce an ultra-high spike, which will be manifested as a "hissing" and "poofing" sound on the headset. This indicates that a large pumping phenomenon will occur inside the circuit every 1.25ms. Therefore, the frequency measured in this step must be greater than 800Hz.

[0049] Step 102: Estimate the magnetic force distribution information inside the magnetic shielding box based on the total magnetic field distribution information. The magnetic force distribution information includes the magnitude and direction of the magnetic force at each measurement location inside the magnetic shielding box.

[0050] Step 103: Apply force to the virtual iron filings distributed in the magnetic shielding box according to the magnetic force distribution information, so that the virtual iron filings will generate adaptive motion under the magnetic force at each measurement position.

[0051] Step 104: Generate a three-dimensional magnetic field distribution map based on the movement and distribution of the virtual iron filings.

[0052] In this embodiment of the invention, the magnetic field distribution information of the Bluetooth headset inside the magnetic shielding box is first measured, and then the magnetic force distribution information inside the magnetic shielding box is estimated based on this. Then, the virtual iron filings inside the magnetic shielding box are controlled to generate adaptive movement according to the magnetic force distribution information. Finally, a three-dimensional magnetic field distribution map is generated based on the movement and distribution state of the virtual iron filings, thus realizing the simulation of the magnetic field inside the Bluetooth headset. Based on this three-dimensional magnetic field distribution map, the staff can intuitively see the magnetic field situation in each area, and then take corresponding effective measures to cancel the magnetic field in areas with stronger magnetic fields, so as to eliminate current noise and improve sound quality.

[0053] When a Bluetooth headset emits a Bluetooth signal, the pumping current is large, and the changing electric field will cause the magnetic field generated by the first type of target component to become even larger, which will couple to the speaker and generate current noise. Therefore, compared with the second type of target component, the magnetic field generated by the first type of target component is the key factor affecting current noise; while the magnetic field generated by the second type of target component is constant and is a secondary factor affecting current noise.

[0054] However, overall, since magnetic fields with different distribution patterns may strengthen or weaken after being superimposed, the magnetic field generated by the first type of target component may become weaker and the weak magnetic field generated by the first type of target component may become stronger after being superimposed. In other words, the distribution of the superimposed magnetic field generated by multiple target components may not be completely consistent with the distribution of the magnetic field generated by a single target component.

[0055] Based on this, in practical applications, one can either select to measure the single magnetic field generated by a key target component to perform single magnetic field simulation analysis, which facilitates the subsequent adoption of corresponding effective measures to reduce current noise for that target component alone; or select to measure the superimposed magnetic field generated by multiple target components to perform superimposed magnetic field simulation analysis, which facilitates the subsequent adoption of corresponding effective measures to reduce current noise for the entire Bluetooth headset.

[0056] In an optional implementation, in step 101 above, when selecting to measure the superimposed magnetic field generated by multiple target components, the following measurement method can be used:

[0057] For each target component, the magnetic field distribution is measured separately: the current target component is placed inside the magnetic shielding box, and other target components are placed outside the magnetic shielding box; when the Bluetooth headset releases the Bluetooth signal, the individual magnetic field distribution information generated by the current target component inside the magnetic shielding box is measured.

[0058] By superimposing the individual magnetic field distribution information corresponding to each target component, the total magnetic field distribution information generated by all target components in the magnetic isolation box is obtained.

[0059] It should be noted that the magnetic field distribution will vary depending on the layout of the target components (such as placement position and orientation). Therefore, when measuring the magnetic field distribution of each target component, the relative fixed position of each target component in the magnetic shielding box should be determined according to the current layout design of the Bluetooth headset.

[0060] Specifically, different measurement methods can be used for different types of target components:

[0061] (1) For the target component that generates a changing magnetic field, measure the distribution information of the single magnetic field generated by the target component in the magnetic shielding box according to the Biot-Savart theorem and the right-hand screw rule.

[0062] The Biot-Savart Law describes the magnetic field generated by a current element at any point P in space. The law states that the magnitude of the magnetic induction intensity dB produced by a current element Idl at a point P is directly proportional to the magnitude of the current element Idl, directly proportional to the sine of the angle between the position vector of the current element Idl at point P and the current element Idl itself, and inversely proportional to the square of the distance from the current element Idl to point P.

[0063] The Biot-Savart law applies to calculating the magnetic field produced by a steady current. This current is the continuous flow of charge through a conductor, the quantity of which does not change with time, and the charge does not accumulate or disappear at any point. It is expressed using the International System of Units (SI) and the equation:

[0064]

[0065] in, It is the source current. It is an integration path. It is a tiny line element of the source current. Let be the unit vector pointing from the current element to the point where the field to be determined is located. The value of vacuum permeability .

[0066] (2) For the target component that generates a constant magnetic field, a magnetic field strength measuring instrument is used to measure the distribution information of a single magnetic field generated by the current target component in the magnetic isolation box.

[0067] In step 102 above, the magnitude and direction of the magnetic force can be estimated based on the magnetic field strength at each measurement location P(x,y,z) according to F=qvB, where q is the charge of the current element, v is the velocity of the current element, and B is the magnetic field strength. Both q and v can be set to constants. For example, as shown... Figure 3 As shown, the forces acting on point P in each magnetic field are F1, F2, and F3, respectively. The magnitudes of these three forces are equal to the length of the line segment, and their directions are indicated by the arrows. Using the parallelogram rule, the magnitude and direction of the resultant force F produced by the superposition of the three magnetic fields can be obtained, as shown below. Figure 4 As shown.

[0068] To further enhance the visual appeal, the three-dimensional magnetic field distribution map generated in step 104 can be categorized and identified into strong and weak magnetic field regions, with the magnetic field strength and direction corresponding to the strong magnetic field regions labeled. These strong and weak magnetic field regions can be distinguished based on the distribution density of the virtual iron filings.

[0069] Example 2

[0070] Please see Figure 5 This invention provides a method for eliminating electrical noise, comprising:

[0071] Step 201: Using the electromagnetic interference simulation analysis method for Bluetooth headsets described in Example 1, generate a three-dimensional magnetic field distribution map of the Bluetooth headset under the current layout.

[0072] Step 202: Based on the magnetic field distribution of the strong magnetic field region in the three-dimensional magnetic field distribution map, adjust the component layout of the Bluetooth headset to weaken the magnetic field in the strong magnetic field region; and / or, add a demagnetizing unit in the Bluetooth headset to cancel the magnetic field in the strong magnetic field region.

[0073] The component layout can specifically include: wiring structure / current direction / length, magnet placement / direction, inductor placement / direction, speaker placement / direction, etc.

[0074] For the battery, a demagnetizing unit is added inside the Bluetooth headset. Specifically, this includes: a first trace (which can be N-shaped) is wound around the battery terminals, and the current direction of the first trace is opposite to the current direction of the terminals, so that the magnetic field generated by the first trace is opposite to the magnetic field generated by the terminals. Figure 6 As shown.

[0075] To address the issue of the power inductor, a demagnetizing unit is added to the Bluetooth headset. Specifically, this involves adding a second trace on the motherboard adjacent to the power inductor, with the current direction of the second trace opposite to that of the power inductor. This ensures that the magnetic field generated by the second trace is opposite to that generated by the power inductor. Figure 7 As shown.

[0076] Of course, in practical applications, multiple methods can be combined to counteract the strong magnetic field generated inside Bluetooth headsets.

[0077] Example 3

[0078] This invention provides a Bluetooth headset manufactured using the current noise cancellation method described in Embodiment 2. Because this Bluetooth headset employs current noise cancellation processing, it exhibits excellent sound quality, enhancing the user experience.

[0079] Example 4

[0080] This invention also provides an electromagnetic interference simulation analysis device for Bluetooth headsets, including a memory and a processor; the memory is used to store instructions; the processor is used to execute the instructions in the memory to implement the electromagnetic interference simulation analysis method for Bluetooth headsets described in Embodiment 1.

[0081] Example 5

[0082] Those skilled in the art will understand that all or part of the steps in the above embodiments can be accomplished by instructions, or by controlling related hardware with instructions. These instructions can be stored in a computer-readable storage medium and loaded and executed by a processor.

[0083] To this end, embodiments of the present invention provide a storage medium storing multiple instructions that can be loaded by a processor to execute the steps in the electromagnetic interference simulation analysis method for Bluetooth headsets provided in embodiments of the present invention.

[0084] The storage medium may include: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0085] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for electromagnetic interference simulation analysis of a Bluetooth headset, wherein the Bluetooth headset includes multiple target components that generate a magnetic field when powered on, and each of the target components is assembled according to a preset layout; characterized in that, The electromagnetic interference simulation analysis method includes: When the Bluetooth headset releases a Bluetooth signal, the total magnetic field distribution information generated by at least one of the target components in the magnetic shielding box is measured. The total magnetic field distribution information includes the magnetic field strength and magnetic field direction at multiple measurement locations in the magnetic shielding box. The magnetic force distribution information inside the magnetic shielding box is estimated based on the total magnetic field distribution information. The magnetic force distribution information includes the magnitude and direction of the magnetic force at each measurement location inside the magnetic shielding box. According to the magnetic force distribution information, a force is applied to the virtual iron filings distributed in the magnetic shielding box, so that the virtual iron filings will generate adaptive motion under the magnetic force at each measurement position; Based on the movement and distribution of the virtual iron filings, a three-dimensional magnetic field distribution map is generated; In the three-dimensional magnetic field distribution map, strong magnetic field regions and weak magnetic field regions are classified and identified, and the magnetic field strength and magnetic field direction corresponding to the strong magnetic field regions are marked. The measurement of the total magnetic field distribution information generated by at least one of the target components within the magnetic shielding box includes: For each target component, the magnetic field distribution is measured separately: the current target component is placed inside the magnetic shielding box, and other target components are placed outside the magnetic shielding box; when the Bluetooth headset releases the Bluetooth signal, the individual magnetic field distribution information generated by the current target component inside the magnetic shielding box is measured. By superimposing the individual magnetic field distribution information corresponding to each target component, the total magnetic field distribution information generated by all target components in the magnetic isolation box is obtained. In the step of measuring the magnetic field distribution, For a target component that generates a changing magnetic field, the distribution information of a single magnetic field generated by the current target component in the magnetic isolation box is measured according to the Biot-Savart theorem and the right-hand screw rule. For a target component that generates a constant magnetic field, a magnetic field strength measuring instrument is used to measure the distribution information of a single magnetic field generated by the current target component within the magnetic isolation box.

2. The electromagnetic interference simulation analysis method for Bluetooth headsets according to claim 1, characterized in that, The target component is a power inductor, wire, battery, speaker, or magnet.

3. A method for canceling static noise in Bluetooth headphones, characterized in that, include: According to the electromagnetic interference simulation analysis method for Bluetooth headsets as described in claim 1, a three-dimensional magnetic field distribution map of the Bluetooth headset under the current layout is generated. Based on the magnetic field distribution in the strong magnetic field region of the three-dimensional magnetic field distribution map, the component layout of the Bluetooth headset is adjusted to weaken the magnetic field in the strong magnetic field region. And / or, a demagnetizing unit is added to the Bluetooth headset to cancel the magnetic field in the strong magnetic field region.

4. The method for eliminating static noise in Bluetooth headsets according to claim 3, characterized in that, The target component is a battery; The addition of a demagnetizing unit in the Bluetooth headset specifically includes: winding a first wire around the battery terminals, wherein the current direction of the first wire is opposite to the current direction of the terminals, so that the magnetic field generated by the first wire is opposite to the magnetic field generated by the terminals.

5. The method for canceling static noise in Bluetooth headsets according to claim 3, characterized in that, The target component is a power inductor; The addition of a demagnetizing unit in the Bluetooth headset specifically includes: adding a second trace on the motherboard in the adjacent area of ​​the power inductor, wherein the current direction of the second trace is opposite to the current direction of the power inductor, so that the magnetic field generated by the second trace is opposite to the magnetic field generated by the power inductor.

6. A Bluetooth headset, characterized in that, The Bluetooth headset is manufactured according to the current noise cancellation method of the Bluetooth headset as described in any one of claims 3 to 5.

7. An electromagnetic interference simulation and analysis device for Bluetooth headsets, characterized in that, Including memory and processor; The memory is used to store instructions; The processor is configured to execute the instructions in the memory to implement the electromagnetic interference simulation analysis method for Bluetooth headsets as described in claim 1 or 2.

8. A storage medium, characterized in that, The storage medium stores multiple instructions, which are adapted for loading by a processor to execute the steps in the electromagnetic interference simulation analysis method for Bluetooth headsets as described in claim 1 or 2.

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