An ultra-low power consumption full-duplex circuit noise reduction communication headset

Abstract

The invention discloses an ultra-low power consumption full-duplex circuit noise reduction communication headset, which relates to the technical field of noise reduction communication headsets. The headset comprises an audio interface unit CN1 connected to a terminal device, a filter F1 and an audio amplifier unit U1 for enhancing a sound pickup signal, a double-pole double-throw electronic analog switch unit U2 for switching a sound pickup and sound emission communication circuit, a resonance unit U3 for emitting a square wave oscillation, and a loudspeaker unit JK1 used as a carrier for sound pickup and sound emission; the steps of switching the sound pickup and sound emission functions through the single unit JK1 include: JK1 controls the switching of the U2 switch through a pulse signal of U3, the connection of JK1 with the sound pickup output port of U2, or the connection of JK1 with the sound emission output port of U2, so as to realize the switching of the communication signal of the MIC port or the SPK port; only one loudspeaker single unit is used, so as to simplify the structural design of the sound pickup, simplify the cavity design, and eliminate the use of the sound pickup rod assembly or the connecting cable, so as to solve the problem that the structure of the two-way communication headset is too complicated.

Description

Technical Field

[0001] The invention relates to the technical field of noise reduction communication earphones, and in particular to an ultra-low power consumption full-duplex circuit noise reduction communication earphone. Background Art

[0002] In order to achieve two-way communication of sound emission and sound pickup, ordinary wired communication headsets need to have a separate speaker sound unit and a sound pickup microphone unit, and the speaker is electrically connected through at least 2-core wires, and the microphone is electrically connected through 2-core wires. The connecting cable is connected to the user device through an adapter plug to realize the dual functions of sound emission and sound pickup of the communication headset.

[0003] In ordinary wired communication headsets, in order to enhance the sound pickup performance of the microphone, the microphone structure generally uses a rod-type adjustable angle or length adjustment method. When sound pickup is needed, the microphone is set as close to the mouth as possible to achieve enhanced sound pickup sensitivity while the single-unit sensitivity of the microphone remains unchanged; among them, the single unit uses a unidirectional noise reduction microphone to reduce the pickup range of ambient noise to reduce the pickup of ambient noise, so that the sound of the main sound source picked up will be relatively clear, thereby achieving the noise reduction function.

[0004] In daily life, given that people are often in various noisy public scenes, they will inevitably encounter various noises. Noise has a great interference on the communication quality of ordinary two-way communication headsets. However, to solve the communication quality problem and improve the quality of two-way communication, including sound clarity, intensity, etc.

[0005] It is necessary to match and use very good microphones and speakers, combined with a structural cavity that can well integrate the microphone and speaker, and to design the best communication circuit solution, as well as excellent sound processing software and noise reduction algorithms, in order to achieve good two-way communication through communication headsets and solve the problem of communication quality. This undoubtedly creates great difficulties in terms of parts matching, sound channel structure design, complex circuit design, and software algorithm design of communication headsets. At the same time, in terms of implementation, the manufacturing cost of communication headsets will also increase significantly, so that even if they have good product strength after they are put on the market, their cost performance is low, making it difficult to promote the products on a large scale in the market.

[0006] In summary, the applicant has found that the prior art has at least the following technical problems:

[0007] In order to realize high-quality two-way communication functions of sound emission and sound pickup, existing communication headsets have the problem of overly complex headset structures. Summary of the invention

[0008] The purpose of the present invention is to provide an ultra-low power consumption full-duplex circuit noise reduction communication headset to solve the problem that the existing communication headset has an overly complex structure in order to achieve high-quality two-way sound emission and sound pickup communication functions.

[0009] The various technical effects that can be produced by the preferred technical solutions among the various technical solutions provided by the present invention are described in detail below.

[0010] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0011] The present invention provides an ultra-low power consumption full-duplex circuit noise reduction communication headset, the ultra-low power consumption full-duplex circuit comprises an audio interface unit CN1 connected to a terminal device, a filter F1 and an audio amplifier unit U1 for enhancing the strength of a sound pickup signal, a double-pole double-throw electronic analog switch unit U2 for switching a sound pickup and sound emission communication circuit, a resonance unit U3 for emitting a square wave oscillation, and a speaker unit JK1 used as a sound pickup and sound emission carrier; wherein F1 is connected to U1 to form a sound pickup signal enhancement group; the sound pickup signal enhancement group is respectively connected to a MIC port of CN1 and a sound pickup output port of U2; the SPK port of CN1 is connected to a sound emission port of U2 Output port; JK1 is connected to the input port of U2; the power supply terminal VCC of U3 is connected in parallel with the power supply terminals VCC of U1 and U2, and the signal output terminal of U3 is connected in parallel with the control terminals EN of U1 and U2; U1, U2 and U3 are grounded respectively; the steps of switching the pickup and sound output functions through the single body JK1: JK1 controls the switching of U2 switch through the pulse signal of U3, the connection of JK1 with the pickup output port of U2, or the connection of JK1 with the sound output port of U2, to realize the communication signal switching of the MIC port or the SPK port; the speaker unit JK1 is a connected earphone; the resonance unit U3 includes a Schmitt trigger.

[0012] In one embodiment, the pulse signal transmitted by U3 has a high pulse width and a low pulse width, wherein the high pulse width is TH and the low pulse width is TL; in each cycle of the pulse signal, the duty ratios of TH and TL are respectively allocated in the range of 20% to 80%.

[0013] In one of the embodiments, the sampling frequency of sound pickup and sound generation should be in the range of 8 to 48 KHz, that is, the oscillation frequency of U3 should be in the range of 8 to 48 KHz.

[0014] In one embodiment, the amplifier circuit type of the audio operational amplifier unit U1 is a differential amplifier circuit, or a single-ended in-phase input circuit, or a single-ended inverting input circuit.

[0015] In one embodiment, the speaker unit JK1 is a dynamic unit, a moving iron unit, or an electrostatic membrane sound-generating unit.

[0016] In one embodiment, the impedance of the speaker unit JK1 is 4 ohms to 2.2K ohms.

[0017] In one embodiment, the MIC port of CN1 includes MIC+ and MIC-, wherein MIC- is grounded.

[0018] The beneficial effects of the present invention are as follows:

[0019] The ultra-low power consumption full-duplex circuit noise reduction communication headset is provided with, including an audio interface unit CN1 for connecting to a terminal device, a filter F1 and an audio operational amplifier unit U1 for enhancing the strength of the sound pickup signal, a double-pole double-throw electronic analog switch unit U2 for switching the sound pickup and sound emission communication circuits, a resonance unit U3 for emitting square wave oscillations, and a speaker unit JK1 used as a sound pickup and sound emission carrier.

[0020] Among them, F1 is connected with U1 to form a sound pickup signal enhancement group; the sound pickup signal enhancement group is respectively connected to the MIC port of CN1 and the sound pickup output port of U2; the SPK port of CN1 is connected to the sound output port of U2; JK1 is connected to the input port of U2; the power supply terminal VCC of U3 is connected in parallel with the power supply terminals VCC of U1 and U2, and the signal output terminal of U3 is connected in parallel with the control terminals EN of U1 and U2; U1, U2 and U3 are grounded respectively.

[0021] By controlling the switch of U2 through the pulse signal of U3 through the single body JK1, the connection between JK1 and the pickup output port of U2, or the connection between JK1 and the sound output port of U2, the communication signal switching of the MIC port or the SPK port is realized.

[0022] (1) By using only one JK1 speaker unit, the structural design of the sound pickup is greatly simplified, the cavity design is simplified, and the use of the sound pickup rod assembly or connecting cables is eliminated, thus solving the problem of the overly complex structure of the two-way communication headset.

[0023] (2) The circuit uses an ultra-low power chip combination of U1, U2 and U3, which only needs to be powered by the microphone excitation voltage of the terminal device. No additional power supply is required, which simplifies the power supply design of the circuit and further reduces the complexity of the circuit structure.

[0024] (3) Thanks to the simplified sound pickup structural design, the product manufacturing process is streamlined, and the cost of the headphones is minimized to the maximum extent. This makes the headphones with this structural design have excellent product strength after they are launched on the market, and their cost performance is also higher, which facilitates the large-scale promotion of the product in the market. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 is a block diagram of an ultra-low power consumption full-duplex circuit of the present invention;

[0027] Figure 2 This is one of the implementation principle diagrams of the ultra-low power consumption full-duplex circuit of the present invention;

[0028] Figure 3 It is a control signal square wave diagram of the ultra-low power consumption full-duplex circuit of the present invention;

[0029] Figure 4 It is a square wave diagram of the ultra-low power consumption full-duplex circuit of the present invention defining the intervals of sound pickup and sound emission. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0031] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In a specific embodiment, an ultra-low power consumption full-duplex circuit noise reduction communication headset is provided, which effectively solves the problem that the existing communication headset needs to achieve high-quality two-way sound transmission and sound pickup communication functions, which requires the coordination of numerous parts, complex sound channel structure design, complex circuit design and excellent software algorithm design, and the headset structure is too complicated.

[0033] Hereinafter, embodiments will be described with reference to the drawings. Note that all contents of the configurations shown in the following embodiments are not necessarily required as the solution to the invention described in the claims.

[0034] An implementation example of an ultra-low power full-duplex circuit noise reduction communication headset Figure 1 As shown, it includes an audio interface unit CN1 connected to a terminal device, a filter F1 and an audio amplifier unit U1 for enhancing the strength of the sound pickup signal, a double-pole double-throw electronic analog switch unit U2 for switching the sound pickup and sound emission communication circuits, a resonance unit U3 for emitting square wave oscillations, and a speaker unit JK1 used as a carrier for sound pickup and sound emission;

[0035] Among them, F1 is connected with U1 to form a sound pickup signal enhancement group; the sound pickup signal enhancement group is respectively connected to the MIC port of CN1 and the sound pickup output port of U2; the SPK port of CN1 is connected to the sound output port of U2; JK1 is connected to the input port of U2; the power supply terminal VCC of U3 is connected in parallel with the power supply terminals VCC of U1 and U2, and the signal output terminal of U3 is connected in parallel with the control terminals EN of U1 and U2; U1, U2 and U3 are respectively grounded;

[0036] Steps for switching the pickup and sound output functions through single JK1: JK1 controls the switch of U2 through the pulse signal of U3, and the connection between JK1 and the pickup output port of U2, or the connection between JK1 and the sound output port of U2, realizes the communication signal switching of the MIC port or the SPK port.

[0037] Among them, the speaker unit JK1 is a connected earphone.

[0038] The MIC port of CN1 includes MIC+ and MIC-, wherein MIC- is grounded.

[0039] (1) By using only one JK1 speaker unit, the structural design of the sound pickup is greatly simplified, the cavity design is simplified, and the use of the sound pickup rod assembly or connecting cables is eliminated, thus solving the problem of the overly complex structure of the two-way communication headset.

[0040] (2) The circuit uses an ultra-low power chip combination of U1, U2 and U3, which only needs to be powered by the excitation voltage of the MIC+ port of the terminal device. No additional power supply is required, which simplifies the power supply design of the circuit and further reduces the complexity of the circuit structure.

[0041] (3) Thanks to the simplified sound pickup structural design, the product manufacturing process is streamlined, and the cost of the headphones is minimized to the maximum extent. This makes the headphones with this structural design have excellent product strength after they are launched on the market, and their cost performance is also higher, which facilitates the large-scale promotion of the product in the market.

[0042] As one optional implementation,

[0043] Among them, Figure 1 and Figure 2 As shown, the resonance unit U3 includes a Schmitt trigger.

[0044] When applied, the Schmitt trigger, as the core component in the circuit, can perfectly realize the full-duplex transmission and reception functions of a single speaker and asynchronous sampling of sound generation and pickup.

[0045] Further, the circuit design is carried out according to Figure 2As shown, in the figure, the resistor R11 is referred to as R, and the capacitor C13 is referred to as C. By using the time constant of charging and discharging of RC, a fixed resonant frequency f can be obtained;

[0046] The parameters are preset as follows: C is assumed to be 1nF = 1e-9, unit: F; R is assumed to be 15kΩ = 15e3, unit: Ω;

[0047] By combining the formula, the oscillation frequency is calculated as follows: f = 1 / (2.2*R*C);

[0048] The result is approximately: f = 30KHz;

[0049] Therefore, it is defined that the pulse signal emitted by U3 has a high pulse width and a low pulse width, wherein the high pulse width is TH and the low pulse width is TL; in each cycle of the pulse signal, the duty ratios of TH and TL are respectively distributed in the range of 20% to 80%.

[0050] like Figure 3 In order to obtain a smoother sound generation and pickup, the high and low pulse widths of each cycle must be consistent, i.e., 50% duty cycle, TH = TL.

[0051] Specific control examples include Figure 2 and Figure 4 As shown, a low pulse width can be defined for the speaker to pick up sound, and a high pulse width can be defined for the speaker to make sound; the pulse signal is sent from pin4 of U3 through R9 to pin6 / 7 of U2 for channel switching.

[0052] Pickup mode: When the pulse width is low, COM1 and COM2 of U2 are connected to NC1 and NC2. JK1 is used as a pickup unit at this time. The sound pressure will drive the voice coil activity to generate an alternating signal, and provide a differential signal source to U1 as a pickup input. The audio signal enters U1 for amplification and then enters R2. C3 outputs the MIC+ signal to the terminal device. The circuit here is a pickup path, which realizes the working principle of using a dynamic speaker as a pickup unit.

[0053] Sounding mode: when the pulse width is high, COM1 and COM2 of U2 are connected with NO1 and NO2, and COM1 and COM2 are disconnected with NC1 and NC2; that is, SPK-Unit is connected through COM1 and COM2 of U2 and NO1 and NO2, and the downlink audio signal from the terminal device is input through R12, that is, SPK+ port, and SPK- port is output. The circuit here is the sounding path, which realizes the working principle of using dynamic speakers as the sounding unit.

[0054] In order to obtain better frequency response for pronunciation and sound pickup, the sampling rate is usually required to be between 38K and 44.1KHz according to the audio bandwidth of 20KHz. Therefore, it is more appropriate to set the oscillation frequency of the Schmitt trigger between 38K and 44.1KHz. The oscillation frequency can be fine-tuned by the above-mentioned RC time constant.

[0055] Therefore, the sampling frequency for picking up sound and emitting sound should be in the range of 8 to 48 KHz, that is, the oscillation frequency of U3 should be in the range of 8 to 48 KHz.

[0056] Furthermore, there may be multiple types of audio amplifier circuits. The amplifier circuit type of the audio operational amplifier unit U1 is a differential amplifier circuit, a single-ended in-phase input circuit, or a single-ended inverting input circuit.

[0057] There are many types of speaker unit JK1 when it is used. The speaker unit JK1 can be a dynamic coil unit, a moving iron unit, or an electrostatic film sound-generating unit.

[0058] The impedance of the speaker unit JK1 is 4 ohms to 2.2K ohms.

[0059] Since the speaker is a low-impedance speaker unit, its sensitivity is extremely low at -55dBV / Pa; while picking up the signal requires impedance transformation on the one hand, and amplifying the signal on the other hand, so as to provide a sufficiently strong and smooth electrical signal to the terminal device, generally -38dBV / Pa.

[0060] The gain calculation formula of the differential amplifier assumes that an ideal op amp is used and all resistors are accurate. The gain can be expressed as: Av = Vout / Vin = Rf / Rin

[0061] Where Rf is the feedback resistor and Rin is the input resistor. First calculate the numerical ratio of Av, and then select the appropriate Rf and Rin values ​​based on this ratio.

[0062] Then calculate the specific Av value ratio and give a specific resistance selection.

[0063] Taking 20dB as an example, a 20dB gain amplifier circuit is constructed using a balanced input operational amplifier (op-amp) in a differential amplifier configuration.

[0064] In this configuration, the gain is determined by the ratio of the external components R13-Rin, R6-Rf. The relationship between the gain A, (in units of voltage ratio) and decibels (dB) is given by the following formula:

[0065] Av(dB)=20log10(Av)

[0066] For a gain of 20dB, we have: 20 = 20log10 (Av)

[0067] Solving the equation gives Av, the numerical ratio of the voltage gain, Av = 10; this means that the output voltage is 10 times the input voltage; based on the gain ratio Av = Rf / Rin = 10, a specific resistance value can be selected to achieve this gain.

[0068] For example, if Rin is set to 1kΩ, based on the voltage gain ratio Av=10, Rf needs to be set to 10kΩ to achieve the desired 20dB gain.

[0069] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described.

[0070] The above is a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered as the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An ultra-low power consumption full-duplex circuit noise reduction communication headset, characterized in that: The ultra-low power full-duplex circuit includes an audio interface unit CN1 connected to the terminal device, a filter F1 and an audio amplifier unit U1 for enhancing the strength of the pickup signal, a double-pole double-throw electronic analog switch unit U2 for switching the pickup and sound communication circuits, a resonance unit U3 for emitting square wave oscillations, and a speaker unit JK1 used as a carrier for pickup and sound generation; Among them, F1 and U1 are connected to form a sound pickup signal enhancement group; The pickup signal enhancement group is connected to the MIC port of CN1 and the pickup output port of U2 respectively; The SPK port of CN1 is connected to the sound output port of U2; JK1 is connected to the input port of U2; The power supply terminal VCC of U3 is connected in parallel with the power supply terminals VCC of U1 and U2, and the signal output terminal of U3 is connected in parallel with the control terminals EN of U1 and U2; U1, U2 and U3 are grounded respectively; The MIC port of CN1 includes MIC+ and MIC-, wherein MIC- is grounded; Steps for switching the pickup and sound output functions through the single JK1: JK1 controls the switch of U2 through the pulse signal of U3, and the connection between JK1 and the pickup output port of U2, or the connection between JK1 and the sound output port of U2, realizes the communication signal switching of the MIC port or the SPK port; The low pulse width can be defined for the speaker to pick up the sound, and the high pulse width can be defined for the speaker to make sound. The pulse signal is sent from pin4 of U3 through R9 to pin6 / 7 of U2 for channel switching. Pickup mode: When the pulse width is low, COM1 and COM2 of U2 are connected to NC1 and NC2. JK1 is used as a pickup unit. The sound pressure will drive the voice coil to generate an alternating signal and provide a differential signal source to U1 as a pickup input. The audio signal enters U1 for amplification and then enters R2. C3 outputs the MIC+ signal to the terminal device. The circuit here is a pickup path, which realizes the working principle of using a dynamic speaker as a pickup unit. Sounding mode: When the pulse width is high, COM1 and COM2 of U2 are connected with NO1 and NO2, and COM1 and COM2 are disconnected with NC1 and NC2; that is, SPK-Unit is connected to the downlink audio signal from the terminal device through R12 input via COM1 and COM2 of U2 and NO1 and NO2, that is, SPK+ port and SPK- port output. The circuit here is the sounding path, realizing the working principle of using dynamic speakers as sounding units; Speaker unit JK1 is the connected earphone; The resonant unit U3 includes a Schmitt trigger; the pulse signal emitted by U3 has a high pulse width and a low pulse width, wherein the high pulse width is TH and the low pulse width is TL; in each cycle of the pulse signal, the duty ratios of TH and TL are respectively distributed in the range of 20% to 80%; The sampling frequency of sound pickup and sound generation should be in the range of 8 to 48KHz, that is, the oscillation frequency of U3 should be in the range of 8 to 48KHz; When applied, the Schmitt trigger, as the core component in the circuit, can perfectly realize the full-duplex transmission and reception functions of a single speaker and asynchronous sampling of sound generation and pickup.

2. The ultra-low power consumption full-duplex circuit noise reduction communication headset according to claim 1, characterized in that: The amplifier circuit type of the audio operational amplifier unit U1 is a differential amplifier circuit, or a single-ended in-phase input circuit, or a single-ended inverting input circuit.

3. The ultra-low power consumption full-duplex circuit noise reduction communication headset according to claim 1, characterized in that: The speaker unit JK1 is a dynamic unit, a moving iron unit, or an electrostatic film sound-generating unit.

4. The ultra-low power consumption full-duplex circuit noise reduction communication headset according to claim 3, characterized in that: The impedance of the speaker unit JK1 is 4 ohms to 2.2K ohms.

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