Digital audio equipment wired cascade device

Abstract

The invention discloses a wired cascade device for digital audio equipment, and relates to the field of audio and video conference systems, the device comprises a host and a plurality of slave equipment, the plurality of slave equipment are connected with the host in a hand-in-hand manner, and the host is connected with the plurality of slave equipment through digital communication lines; each slave device comprises an input end, a digital bus transmission relay and an output end which are connected in sequence; the input end of the slave device connected with the host is connected with the output end of the host, and the output ends and the input ends of the other slave devices are sequentially connected. The device has the advantages that more slave devices are supported, interference and steal are not prone to occurring, EMC performance and signal integrity are improved, wire cost is saved, and the whole device is simpler and more attractive.

Description

Technical Field

[0001] The present application relates to the field of audio and video conferencing systems, and in particular to a wired cascading device for digital audio equipment. Background Art

[0002] In the field of audio and video conferencing system applications, although small conference room products have been widely used, there are still aspects that need to be improved in the conference venue. For example, if small conference room products are used in large conference rooms, the sound pickup and playback volume will be small. In terms of sound pickup, although the sound pickup distance can be improved through microphone array technology, in larger conference rooms, small conference products can no longer meet the requirements of long-distance sound pickup. In terms of sound playback, small conference products cannot meet the sound field requirements for people who are far away from small conference products.

[0003] In order to solve the problem of sound pickup and playback of the above small conference products in large conference rooms, multiple small conference products are usually cascaded to expand the sound pickup and playback range. Currently, the more commonly used forms are star shape and hand-in-hand. Figure 1 As shown, it can be seen that the signal is transmitted by the PC and the main device via USB bidirectional digital signal communication, and at the same time, the main device communicates with the 4 external slave devices via bidirectional analog signal communication to increase the pickup and playback range. The power is first supplied to the main device, and then the main device supplies power to the other 4 slave devices through the communication line. The star shape is adopted, and the wires are arranged in a messy manner, which will not look beautiful on the conference table. At the same time, the main device and the slave device transmit analog signals, which are more easily interfered, generating noise and causing unclear calls. Hand in hand Figure 2 As shown, the signal is transmitted by the USB bidirectional digital signal between the PC and the master device. There are two communication methods between the master device and the slave device: 1. The microphone analog signals of the 4 slave devices are mixed and uniformly transmitted to the master device. The advantage of this method is that the number of wires is small and the wires can be made thinner. The disadvantage is that the microphone analog signals are mixed, which will affect the voice clarity. 2. The microphone analog signals of the 4 slave devices are transmitted to the master device separately. The advantage of this method is that the signals are independent and the voice clarity is good. The disadvantage is that the number of wires is large and the wires will be thicker. These two methods have a common problem. The master and slave devices are transmitted through analog signals, which are more easily interfered, generating noise and causing unclear calls. The power supply is first supplied to the master device, and then the master device supplies power to slave device 1 through the communication line, and then connects to the other 3 slave devices in series.

[0004] Therefore, how to provide a wired cascade of digital audio devices with better transmission effect is a problem that needs to be solved urgently. Summary of the invention

[0005] In order to solve the above problems, the present application provides a digital audio device wired cascade device, device, electronic device and medium.

[0006] In a first aspect, the present application provides a wired cascade device for digital audio devices, the device comprising a host and a plurality of slave devices, the plurality of slave devices being connected to the host in a hand-in-hand manner, and the host and the plurality of slave devices being connected via a digital communication line; Each of the slave devices comprises an input terminal, a digital bus transmission relay and an output terminal connected in sequence; The input end of the slave device connected to the host is connected to the output end of the host, and the output ends and input ends of other slave devices are connected in sequence.

[0007] Optionally, the input end of the slave device includes an input end impedance matching circuit and an input end signal integrity filtering circuit; One end of the input impedance matching circuit is connected to the input connector of the digital communication line, and the other end is connected to the input signal integrity filter circuit; One end of the input-end signal integrity filter circuit is connected to the digital bus transmission relay, and the other end is connected to the input-end impedance matching circuit.

[0008] Optionally, the input impedance matching circuit includes a DC bias filter circuit, an AC coupling capacitor, a separation termination resistor and a common mode choke connected in sequence, the common mode choke is connected to the input signal integrity filter circuit, and the DC bias filter circuit is connected to the input connector of the digital communication line.

[0009] Optionally, the input signal integrity filter circuit includes a notch filter, a balancing capacitor and a low-pass filter connected in sequence, the low-pass filter is connected to the common mode choke, and the notch filter is connected to the digital bus transmission relay.

[0010] Optionally, the output end of the slave device includes an output end impedance matching circuit and an output end signal integrity filtering circuit; One end of the output impedance matching circuit is connected to the output connector of the digital communication line, and the other end is connected to the output signal integrity filter circuit; One end of the output-end signal integrity filter circuit is connected to the digital bus transmission relay, and the other end is connected to the output-end impedance matching circuit.

[0011] Optionally, the output impedance matching circuit includes a DC bias filter circuit, an AC coupling capacitor, a separation termination resistor and a common mode choke connected in sequence, the common mode choke is connected to the output signal integrity filter circuit, and the DC bias filter circuit is connected to the output connector of the digital communication line.

[0012] Optionally, the output signal integrity filter circuit includes a notch filter, a balancing capacitor and a low-pass filter connected in sequence, the low-pass filter is connected to the common mode choke, and the notch filter is connected to the digital bus transmission relay.

[0013] Optionally, the number of slave devices is 8.

[0014] Optionally, the slave device further includes a digital signal isolation module and a DSP module, and the digital signal isolation module is arranged between the digital bus transmission relay and the DSP module.

[0015] Optionally, the host is connected to a power source via a power cord and connected to a PC via a USB cable.

[0016] In summary, the present application includes at least one of the following beneficial technical effects: 1. The host does not have a microphone and speaker, and can be placed in a corner with a PC and a power supply without occupying the conference table. The conference table only needs to be placed on 1 to 8 slave devices, which is more simple and beautiful as a whole.

[0017] 2. Up to 8 slave devices can be connected. The slave devices use digital signal transmission, which is not easy to interfere and will not generate circuit noise, truly achieving high-fidelity voice transmission.

[0018] 3. Unique digital transmission protocol with encryption, making it difficult to eavesdrop.

[0019] 4. The digital transmission can reach up to 40 meters, which is better suited for rectangular conference tables and round conference tables, while the star shape is only more suitable for round conference tables.

[0020] 5. Digital transmission requires fewer wires, which are thinner and more beautiful than analog transmission wires, and can also save wire costs.

[0021] 6. The delay is less than 50us, and the low synchronization delay is of great significance to the audio system's ANC active noise reduction, multi-zone recognition and other voice and acoustic applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the existing star-shaped connection structure in the background technology of this application.

[0023] Figure 2 It is a schematic diagram of the existing hand-in-hand connection structure in the background technology of this application.

[0024] Figure 3 It is a schematic diagram of the connection structure of the wired cascade device of the digital audio equipment according to the embodiment of the present application.

[0025] Figure 4It is a schematic diagram of the slave device connection structure of the wired cascade device of the digital audio device according to the embodiment of the present application.

[0026] Figure 5 It is a schematic diagram of the input circuit structure of the slave device according to an embodiment of the present application.

[0027] Figure 6 It is a schematic diagram of the output circuit structure of the slave device in an embodiment of the present application.

[0028] Reference numerals: Input end signal integrity filter circuit 110; input end impedance matching circuit 120; digital bus transmission relay 200; output end signal integrity filter circuit 310; output end impedance matching circuit 320; digital signal isolation module 400; DSP module 500. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments.

[0030] In the description of the embodiments of the present application, words such as "illustrative", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "illustrative", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "illustrative", "for example" or "for example" is intended to present related concepts in a specific way.

[0031] In the description of the embodiments of the present application, unless otherwise stated, the meaning of the term "multiple" refers to two or more. For example, multiple systems refer to two or more systems, and multiple screen terminals refer to two or more screen terminals. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. The terms "include", "comprise", "have" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0032] like Figure 3As shown, a wired cascade device for digital audio devices provided by an embodiment of the present invention includes a host and multiple slave devices, multiple slave devices are connected to the host in a hand-in-hand manner, and the host and multiple slave devices are connected through a digital communication line. Each of the slave devices includes an input end, a digital bus transmission relay 200 and an output end connected in sequence. The input end of the slave device connected to the host is connected to the output end of the host, and the output ends and input ends of the other slave devices are connected in sequence.

[0033] The wired cascade device for digital audio devices provided in the embodiment of the present invention has a structure that is a further improvement on the existing hand-in-hand form. Among multiple slave devices, only one is directly connected to the host, and the other slave devices are connected in sequence. In order to support more slave devices and improve the transmission quality, the connection between the slave device and the host, as well as the connection between the slave devices, all adopt digital communication lines. Due to the use of digital signal transmission, it is not easy to interfere, and no circuit noise will be generated, so that high-fidelity voice transmission can be truly achieved.

[0034] Compared with the analog transmission method adopted by the existing hand-in-hand form, in the wired cascade device of the digital audio device of the present application, up to 8 slave devices can be connected. Due to the use of digital communication lines, the longest connection distance of the digital transmission method can reach 40 meters, which is better adapted to rectangular conference tables and round conference tables, while the star shape of the prior art is only more suitable for round conference tables. In actual use, the host can maintain a long distance between the slave device. The host does not have a microphone and a speaker. The host, the PC computer, and the power supply are placed in a corner. The host is connected to the power supply via a power cord and connected to the PC computer via a USB cable. The host does not occupy the conference desktop. A certain number of slave devices can be placed on the conference desktop, which is more concise and beautiful as a whole.

[0035] At the same time, digital transmission uses fewer wires, which are thinner and more beautiful than analog transmission wires, and can also save wire costs.

[0036] In this embodiment, in order to be able to cooperate with the digital communication line to transmit digital signals, each slave device includes an input end, a digital bus transmission relay 200 and an output end connected in sequence. Among them, the input end of the slave device connected to the host is connected to the output end of the host, the output ends and input ends of other slave devices are connected in sequence, and the output end of the last slave device is not connected. When working, the host outputs a digital signal to the first slave device connected to it through its output end. After the first slave device receives the digital signal through the input end, it transmits the signal to its own output end through the digital bus transmission relay 200. The signal at the output end is transmitted to the input end of the second slave device through the digital communication line connected to it, and so on, and finally transmits the digital signal to the last slave device. Among them, the digital bus transmission relay 200 can transmit multiple signals at the same time, and each path corresponds to a slave device, that is, the first signal corresponds to the first slave device, that is, the second signal corresponds to the second slave device, and so on.

[0037] The specific structure of the slave device will be described below. The structure of each slave device is the same. In actual use, any slave device can be replaced in the order of connection without affecting the work.

[0038] As a preferred implementation of the embodiment of the present invention, Figure 4 As shown, the input end of the slave device includes an input impedance matching circuit 120 and an input signal integrity filter circuit 110; one end of the input impedance matching circuit 120 is connected to the input connector of the digital communication line, and the other end is connected to the input signal integrity filter circuit 110; one end of the input signal integrity filter circuit 110 is connected to the digital bus transmission relay 200, and the other end is connected to the input impedance matching circuit 120. The output end of the slave device includes an output impedance matching circuit 320 and an output signal integrity filter circuit 310; one end of the output impedance matching circuit 320 is connected to the output connector of the digital communication line, and the other end is connected to the output signal integrity filter circuit 310; one end of the output signal integrity filter circuit 310 is connected to the digital bus transmission relay 200, and the other end is connected to the output impedance matching circuit 320. The digital bus transmission relay 200 is connected to the DSP module 500 through the digital signal isolation module 400.

[0039] Among them, the input end and the output end are both composed of an impedance matching circuit and a signal integrity filtering circuit. The input impedance matching circuit 120 of the input end and the output impedance matching circuit of the output end adopt exactly the same circuit structure, and the input signal integrity filtering circuit 110 of the input end and the output signal integrity filtering circuit of the output end adopt exactly the same circuit structure.

[0040] The DSP module 500 is used to execute the voice output function of the slave device, and the digital signal isolation module 400 is used to isolate the signal interference between the DSP module 500 and the digital bus transmission relay 200 .

[0041] At the same time, the DSP module 500 also includes an encryption module based on the digital voice transmission method, which can encrypt the digital voice signal, improve security, and is not easy to be eavesdropped.

[0042] Specifically, Figure 5-Figure 6 As shown, the specific structures of the input impedance matching circuit 120 and the output impedance matching circuit 320 are a DC bias filter circuit, an AC coupling capacitor, a separation termination resistor and a common mode choke coil connected in sequence.

[0043] like Figure 5 As shown, in the input impedance matching circuit 120, the common mode choke is connected to the input signal integrity filter circuit 110, and the DC bias filter circuit is connected to the input connector J6 of the digital communication line. The AC coupling capacitors are C154 and C121, the separation termination resistors are R138 and R133, and the common mode choke is FER5. The DC bias filter circuit is composed of inductors L14 and L15 and capacitors C151, C169, and C183.

[0044] like Figure 6 As shown, in the output impedance matching circuit 320, the common mode choke is connected to the output signal integrity filter circuit 310, and the DC bias filter circuit is connected to the output connector J1 of the digital communication line. The AC coupling capacitors are C5 and C1, the separation termination resistors are R1 and R2, and the common mode choke is FER1. The DC bias filter circuit is composed of inductors L2 and L4 and capacitors C4, C8, and C11.

[0045] like Figure 5-Figure 6 As shown, the specific structures of the input-end signal integrity filter circuit 110 and the output-end signal integrity filter circuit 310 are a notch filter, a balancing capacitor, and a low-pass filter connected in sequence.

[0046] like Figure 5 As shown, in the input end signal integrity filter circuit 110, the low-pass filter is connected to the common mode choke FER5, and the notch filter is connected to the signal input end of the digital bus transmission relay 200. The low-pass filter is composed of inductors L3 and L18 and capacitors C135 and C155, the notch filter is composed of feedback inductors FB15 and FB17 and capacitor C178, and the balancing capacitor is C181.

[0047] like Figure 6As shown, in the output end signal integrity filter circuit 310, the low-pass filter is connected to the common mode choke FER1, and the notch filter is connected to the signal output end of the digital bus transmission relay 200. The low-pass filter is composed of inductors L1 and L16 and capacitors C3 and C12, the notch filter is composed of feedback inductors FB1 and FB2 and capacitor C9, and the balancing capacitor is C10.

[0048] Based on the above circuit structure, the EMC performance and signal integrity of the input and output ends of the slave device can be effectively improved. The delay can be reduced to less than 50us, and the low delay of synchronization is of great significance to the voice and acoustic applications such as ANC active noise reduction and multi-zone recognition of the audio system.

[0049] In summary, the wired cascading device for digital audio devices provided in this embodiment has the following advantages: 1. The host does not have a microphone and speaker, and can be placed in a corner with a PC and a power supply without occupying the conference table. The conference table only needs to be placed on 1 to 8 slave devices, which is more simple and beautiful as a whole.

[0050] 2. Up to 8 slave devices can be connected. The slave devices use digital signal transmission, which is not easy to interfere and will not generate circuit noise, truly achieving high-fidelity voice transmission.

[0051] 3. Unique digital transmission protocol with encryption, making it difficult to eavesdrop.

[0052] 4. The digital transmission can reach up to 40 meters, which is better suited for rectangular conference tables and round conference tables, while the star shape is only more suitable for round conference tables.

[0053] 5. Digital transmission requires fewer wires, which are thinner and more beautiful than analog transmission wires, and can also save wire costs.

[0054] 6. The delay is less than 50us, and the low synchronization delay is of great significance to the audio system's ANC active noise reduction, multi-zone recognition and other voice and acoustic applications.

[0055] In several embodiments disclosed in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and a module, a program segment or a part of the code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0056] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0057] The above is only an exemplary embodiment of the present disclosure and cannot be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the disclosure of the specification and the truth of practice, those skilled in the art will easily think of other embodiments of the present disclosure.

[0058] This application is intended to cover any variation, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art not described in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

[0059] The wired cascade device for digital audio equipment designed by the present invention can use integrated devices or other forms of discrete devices to build circuits to implement the core principles described in the present invention, namely, digital signal isolation circuits, voice encryption circuits, low-latency circuits, digital voice transmission circuits, and digital long-distance transmission circuits. Regardless of the implementation method, it is within the protection rights claimed by the present invention.

Claims

1. A wired cascade device for digital audio equipment, characterized in that: The device comprises a host and a plurality of slave devices, wherein the plurality of slave devices are connected to the host in a hand-in-hand manner, and the host and the plurality of slave devices are connected via a digital communication line; Each of the slave devices comprises an input terminal, a digital bus transmission relay and an output terminal connected in sequence; The input end of the slave device connected to the host is connected to the output end of the host, and the output ends and input ends of other slave devices are connected in sequence.

2. The wired cascade device for digital audio equipment according to claim 1, characterized in that: The input end of the slave device includes an input end impedance matching circuit and an input end signal integrity filtering circuit; One end of the input impedance matching circuit is connected to the input connector of the digital communication line, and the other end is connected to the input signal integrity filter circuit; One end of the input-end signal integrity filter circuit is connected to the digital bus transmission relay, and the other end is connected to the input-end impedance matching circuit.

3. The wired cascade device for digital audio equipment according to claim 2, characterized in that: The input impedance matching circuit includes a DC bias filter circuit, an AC coupling capacitor, a separation termination resistor and a common mode choke connected in sequence, the common mode choke is connected to the input signal integrity filter circuit, and the DC bias filter circuit is connected to the input connector of the digital communication line.

4. The wired cascade device for digital audio equipment according to claim 3, characterized in that: The input-end signal integrity filter circuit includes a notch filter, a balancing capacitor, and a low-pass filter connected in sequence, the low-pass filter is connected to the common-mode choke, and the notch filter is connected to the digital bus transmission relay.

5. The wired cascade device for digital audio equipment according to claim 1, characterized in that: The output end of the slave device includes an output end impedance matching circuit and an output end signal integrity filtering circuit; One end of the output impedance matching circuit is connected to the output connector of the digital communication line, and the other end is connected to the output signal integrity filter circuit; One end of the output-end signal integrity filter circuit is connected to the digital bus transmission relay, and the other end is connected to the output-end impedance matching circuit.

6. The wired cascade device for digital audio equipment according to claim 5, characterized in that: The output impedance matching circuit includes a DC bias filter circuit, an AC coupling capacitor, a separation termination resistor and a common mode choke connected in sequence, the common mode choke is connected to the output signal integrity filter circuit, and the DC bias filter circuit is connected to the output connector of the digital communication line.

7. The wired cascade device for digital audio equipment according to claim 6, characterized in that: The output end signal integrity filter circuit includes a notch filter, a balancing capacitor and a low-pass filter connected in sequence, the low-pass filter is connected to the common mode choke, and the notch filter is connected to the digital bus transmission relay.

8. The wired cascade device for digital audio equipment according to claim 1, characterized in that: The number of slave devices is 8.

9. The wired cascade device for digital audio equipment according to claim 1, characterized in that: The slave device further comprises a digital signal isolation module and a DSP module, wherein the digital signal isolation module is arranged between the digital bus transmission relay and the DSP module.

10. The wired cascade device for digital audio equipment according to claim 1, characterized in that: The host is connected to a power source via a power cord and connected to a PC via a USB cable.

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