A signal processing device with multi-path frequency division and independent limiting

Abstract

The utility model discloses a kind of signal processing devices with multi-path frequency division and independent amplitude limiting, comprising: signal input end, frequency division filter circuit, frequency band amplitude limiting processing circuit, signal mixing circuit and power amplifier circuit;Frequency division filter circuit is accessed original audio signal by signal input end and carries out filtering, frequency division to form multiple first audio signals and output to corresponding frequency band amplitude limiting processing circuit to carry out amplitude limiting processing;Signal mixing circuit is used to mix multiple first audio signals into a second audio signal and output to passive frequency divider's multiple frequency division audio amplifier after amplification processing by power amplifier circuit.The utility model divides original audio signal into different frequency band first audio signal to carry out independent amplitude limiting, realizes the effective protection of audio amplifier loudspeaker unit;Meanwhile, after mixing multiple first audio signals after amplitude limiting processing, output to a power amplifier circuit, without multiple power amplification, effectively reduce system cost.

Description

Technical Field

[0001] This invention relates to frequency dividers, and more particularly to a signal processing device with multi-channel frequency division and independent amplitude limiting. Background Technology

[0002] Most professional sound reinforcement speakers currently use a multi-channel architecture. For example, with existing active crossover circuits, each output of the audio processor requires a corresponding power amplifier circuit to drive one multi-channel speaker unit. In other words, the audio processor needs to individually filter and limit the signal for each channel before connecting it to the corresponding power amplifier unit, and then output it to the corresponding speaker unit. Clearly, when processing signals, the number of power amplifier channels and audio processors required corresponds to the number of crossover channels in the speaker system, resulting in a complex and costly system. Utility Model Content

[0003] In order to overcome the shortcomings of the existing technology, the purpose of this utility model is to provide a signal processing device with multi-channel frequency division and independent amplitude limiting, which can solve the problems of system complexity and high cost caused by the multiple power amplifier channels of existing audio processors.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A signal processing device with multi-channel frequency division and independent amplitude limiting, the signal processing device comprising: a signal input terminal, a signal processing circuit, and a power amplifier circuit; wherein, the signal processing circuit comprises: a frequency division filtering circuit, a frequency band limiting processing circuit, and a signal mixing circuit;

[0006] The input terminal of the frequency division filter circuit is connected to the original audio signal through the signal input terminal, and each output terminal of the frequency division filter circuit is electrically connected to the corresponding frequency band limiting processing circuit. The frequency division filter circuit is used to filter and divide the original audio signal to form multiple first audio signals, and output each first audio signal to the corresponding frequency band limiting processing circuit for limiting processing.

[0007] The signal mixing circuit has multiple input terminals that are electrically connected to the output terminals of each frequency band limiting processing circuit, and its output terminal is electrically connected to the power amplifier circuit. The signal mixing circuit is used to mix multiple first audio signals into one second audio signal and then amplify and output the second audio signal through the power amplifier circuit.

[0008] Furthermore, the frequency division filtering circuit includes an FIR filter, the input of which obtains the original audio signal through the signal input terminal; each output terminal of the FIR filter is electrically connected to the input terminal of the corresponding frequency band limiting processing circuit, for filtering and frequency division of the original audio signal to obtain multiple first audio signals and outputting each audio signal to the corresponding frequency band limiting processing circuit.

[0009] Furthermore, the frequency division filtering circuit includes an IIR filter and an FIR filter; the IIR filter is used to perform frequency division processing on the original audio signal to generate multiple first audio signals, and the FIR filter is used to perform filtering processing on the original audio signal or to perform filtering processing on each first audio signal after frequency division.

[0010] Furthermore, when there is one FIR filter, the input terminal of the FIR filter is electrically connected to the signal input terminal, and the output terminal is electrically connected to the input terminal of the IIR filter. Each output terminal of the IIR filter is electrically connected to the input terminal of the corresponding frequency band limiting processing circuit. The FIR filter is used to filter the original audio signal. The IIR filter is used to perform frequency division processing on the filtered original audio signal to generate multiple first audio signals.

[0011] Furthermore, when there are multiple FIR filters, the input terminal of the IIR filter is electrically connected to the signal input terminal, and each output terminal is electrically connected to the input terminal of the corresponding FIR filter; the output terminal of each FIR filter is electrically connected to the corresponding frequency band limiting processing circuit; the IIR filter is used to divide the original audio signal to obtain multiple first audio signals; the FIR filter is used to filter each first audio signal.

[0012] Furthermore, the signal processing device with multi-channel frequency division and independent amplitude limiting includes a passive frequency divider and a multi-channel speaker enclosure; wherein, the input terminal of the passive frequency divider is electrically connected to the output terminal of the power amplifier circuit through the signal output terminal, and each output terminal is electrically connected to the corresponding speaker unit of the multi-channel speaker enclosure, for dividing the second audio signal to generate multiple second audio signals and outputting them to the corresponding speaker units of the multi-channel speaker enclosure respectively.

[0013] Furthermore, the passive crossover has at least two output terminals; when the multi-way speaker includes a tweeter unit and a mid-bass driver unit, and the passive crossover has two output terminals, the two output terminals of the passive crossover are electrically connected to the tweeter unit and the mid-bass driver unit of the multi-way speaker, respectively; when the multi-way speaker includes a tweeter unit, a midrange driver unit, and a woofer unit, and the passive crossover has three output terminals, the three output terminals of the passive crossover are electrically connected to the tweeter unit, the midrange driver unit, and the woofer unit of the multi-way speaker, respectively.

[0014] Furthermore, the frequency band limiting processing circuit comprises N circuits, where N is a natural number greater than or equal to 2.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] This invention first divides the original audio signal to obtain multiple audio signals with different frequency ranges. Then, each audio signal is independently limited. The multiple limited audio signals are then mixed to form a single audio signal, which is then amplified by a power amplifier circuit. This method of first dividing the signal and then mixing it only requires a single power amplifier circuit, greatly reducing the system design cost and complexity. At the same time, it can also independently limit the audio signals in different frequency ranges, effectively protecting the tweeter, midrange, and woofer units. Attached Figure Description

[0017] Figure 1 A block diagram of a signal processing device with multi-channel frequency division and independent amplitude limiting provided by this utility model;

[0018] Figure 2 for Figure 1 The block diagram of a signal processing device with multiple frequency division and independent amplitude limiting, including an FIR filter in the frequency division filtering circuit;

[0019] Figure 3 for Figure 1 The block diagram of a signal processing device with multiple frequency division and independent amplitude limiting, which includes an FIR filter and an IIR filter in the frequency division filtering circuit;

[0020] Figure 4 for Figure 1 The diagram shows a signal processing device with multi-channel frequency division and independent amplitude limiting, where the frequency division filtering circuit includes multiple FIR filters and IIR filters. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0022] This utility model provides a signal processing device with multi-channel frequency division and independent amplitude limiting, such as Figure 1 As shown, it includes a signal input terminal, a signal processing circuit, and a power amplifier circuit.

[0023] The input terminal of the signal processing circuit is electrically connected to the audio signal source to acquire the original audio signal. The output terminal of the signal processing circuit is also electrically connected to the power amplifier circuit to amplify the processed audio signal before outputting it.

[0024] Specifically, the signal processing circuit includes a frequency division filtering circuit, a frequency band limiting processing circuit, and a signal mixing circuit. The input terminal of the frequency division filtering circuit is also the input terminal of the signal processing circuit. It is electrically connected to the audio signal source through the signal input terminal and is used to acquire the original audio signal, filter and divide the original audio signal to generate multiple first audio signals.

[0025] The frequency band limiting processing circuit comprises multiple circuits. Each frequency band limiting processing circuit is used to limit the amplitude of each first audio signal. Specifically, the input terminal of the frequency band limiting processing circuit is electrically connected to the corresponding output terminal of the frequency division filtering circuit, and is used to acquire the corresponding first audio signal and limit it. The output terminal of the frequency band limiting processing circuit is also electrically connected to the input terminal of the signal mixing circuit, and is used to output the corresponding first audio signal after amplitude limiting to the signal mixing circuit.

[0026] The output of the signal mixing circuit, which is also the output of the frequency division filter circuit, is electrically connected to the input of the power amplifier circuit. It is used to mix the multiple first audio signals obtained from the multi-band limiting processing circuit to obtain the second audio signal, and to output the second audio signal to the power amplifier circuit for amplification and output.

[0027] This invention filters the original audio signal and then divides it into multiple first audio signals. Each first audio signal is then individually limited before being combined into a single signal, which is then output to a power amplifier circuit for amplification. Because of this frequency division followed by mixing, only one power amplifier circuit is needed, eliminating the need for multiple amplifier channels to achieve frequency band limiting protection and significantly reducing system costs. Furthermore, this invention divides the signal into different frequency bands during the limiting process, and then independently limits each signal. This allows for individual processing of the midrange and high-frequency units, as well as effective protection for the woofer, midrange, and tweeter units.

[0028] Furthermore, such as Figure 2 As shown, the frequency division filtering circuit of this invention preferably includes an FIR filter. The FIR filter is a Finite Impulse Response filter. This invention uses an FIR filter to filter and divide the original audio signal. Specifically, the FIR filter has one input terminal and multiple output terminals. The input terminal of the FIR filter is electrically connected to the audio signal source through a signal input terminal, and each output terminal is electrically connected to the input terminal of the corresponding frequency band limiting processing circuit. This is used to acquire the original audio signal, filter and divide the original audio signal to form multiple first audio signals, and output each first audio signal to the corresponding frequency band limiting processing circuit for individual limiting processing. This invention, by utilizing an FIR filter to filter and divide the original audio signal, can reduce the phase shift generated in the mixed signal.

[0029] Furthermore, such as Figure 3As shown, the frequency division filtering circuit of this utility model preferably includes an FIR filter and an IIR filter. The IIR filter is an infinite impulse response digital filter. Specifically, the IIR filter is used to perform frequency division processing on the original audio signal; the FIR filter is used to filter the original audio signal. The input terminal of the FIR filter, which is also the input terminal of the signal processing circuit, is electrically connected to the signal input terminal to acquire the original audio signal and perform filtering processing on it. The output terminal of the FIR filter is also electrically connected to the input terminal of the IIR filter, and each output terminal of the IIR filter is electrically connected to the corresponding frequency band limiting processing circuit. That is, the FIR filter filters the original audio signal, and the IIR filter performs frequency division processing on the filtered original audio signal to generate multiple first audio signals and outputs each first audio signal to the corresponding frequency band limiting processing circuit for limiting processing.

[0030] More preferably, such as Figure 4 As shown, the frequency division filtering circuit of this invention preferably includes multiple FIR filters and IIR filters. That is, this invention first divides the original audio signal into frequencies using an IIR filter, then filters each of the divided first audio signals using each FIR filter, and finally outputs each first audio signal to the corresponding frequency band limiting processing circuit. Specifically, the input terminal of the IIR filter is the input terminal of the signal processing circuit, electrically connected to the audio signal source through the signal input terminal, used to acquire the original audio signal and divide it into multiple first audio signals. Each output terminal of the IIR filter is electrically connected to the corresponding output terminal of the corresponding IIR filter through the input terminal of each FIR filter, and electrically connected to the input terminal of the corresponding frequency band limiting processing circuit, used to filter each first audio signal and output it to the corresponding frequency band limiting processing circuit for limiting processing.

[0031] This invention uses an FIR filter to filter the signal and an IIR filter to divide the signal into frequencies. While achieving phase shift compensation for mid-to-high frequency signals, it can also reduce the time delay caused by the FIR filter frequency division. This solution is suitable for live audio playback, which can greatly reduce latency and ensure real-time sound reinforcement. It is more suitable for on-site real-time sound reinforcement scenarios.

[0032] More preferably, the frequency band limiting processing circuit in this invention includes N circuits, where N is a natural number greater than or equal to 2. More specifically, N is preferably 2, 3, or 4. For example, when N is 3, the frequency band limiting processing circuit includes a first frequency band limiting processing circuit, a second frequency band limiting processing circuit, and a third frequency band limiting processing circuit. The signal frequency range of the first audio signal is [20Hz~600Hz], i.e., the low-frequency band; the signal frequency range of the second audio signal is [600Hz~1200Hz], i.e., the mid-frequency band; and the signal frequency range of the third audio signal is [1.2kHz~20kHz], i.e., the high-frequency band. In other words, this invention divides the original audio signal into multiple first audio signals of different frequency bands through a frequency division filtering circuit, and then individually limits the first audio signal of the corresponding frequency band through the corresponding frequency band limiting processing circuit, achieving independent limiting processing of mid- and high-frequency signals and effectively protecting mid- and high-frequency signals. This invention achieves frequency division through an IIR filter and phase compensation filtering through an FIR filter. The FIR filter also compensates for the phase shift of mid and high frequencies. Furthermore, since the frequency division of the IIR filter does not produce time delay, it is more suitable for real-time amplification of live broadcasts.

[0033] More preferably, the signal output terminal is also electrically connected to the speaker unit of the multi-way speaker via a passive crossover, for outputting the second audio signal to the passive crossover for frequency division and then inputting it to the speaker unit of the multi-way speaker to achieve audio amplification playback. The passive crossover has at least two output terminals.

[0034] For example, a multi-way speaker includes a tweeter unit and a mid-bass driver unit. When the passive crossover has two outputs, the two outputs of the passive crossover are electrically connected to the tweeter unit and the mid-bass driver unit of the multi-way speaker, respectively, to achieve sound reinforcement. As another example, a multi-way speaker includes a tweeter unit, a midrange driver unit, and a woofer unit. When the passive crossover has three outputs, the three outputs of the passive crossover are electrically connected to the tweeter unit, the midrange driver unit, and the woofer unit of the multi-way speaker, respectively, to achieve sound reinforcement.

[0035] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. A signal processing device with multi-channel frequency division and independent amplitude limiting, characterized in that, The signal processing device includes: a signal input terminal, a signal processing circuit, and a power amplifier circuit; wherein, the signal processing circuit includes: a frequency division filtering circuit, a frequency band limiting processing circuit, and a signal mixing circuit; The input terminal of the frequency division filter circuit is connected to the original audio signal through the signal input terminal, and each output terminal of the frequency division filter circuit is electrically connected to the corresponding frequency band limiting processing circuit. The frequency division filter circuit is used to filter and divide the original audio signal to form multiple first audio signals, and output each first audio signal to the corresponding frequency band limiting processing circuit for limiting processing. The signal mixing circuit has multiple input terminals that are electrically connected to the output terminals of each frequency band limiting processing circuit, and its output terminal is electrically connected to the power amplifier circuit. The signal mixing circuit is used to mix multiple first audio signals into one second audio signal and then amplify and output the second audio signal through the power amplifier circuit.

2. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 1, characterized in that, The frequency division filtering circuit includes an FIR filter. The input terminal of the FIR filter obtains the original audio signal through the signal input terminal. Each output terminal of the FIR filter is electrically connected to the input terminal of the corresponding frequency band limiting processing circuit, which is used to filter and divide the original audio signal to obtain multiple first audio signals and output each audio signal to the corresponding frequency band limiting processing circuit.

3. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 1, characterized in that, The frequency division filtering circuit includes an IIR filter and an FIR filter; the IIR filter is used to perform frequency division processing on the original audio signal to generate multiple first audio signals, and the FIR filter is used to perform filtering processing on the original audio signal or to perform filtering processing on each first audio signal after frequency division.

4. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 3, characterized in that, When there is one FIR filter, the input terminal of the FIR filter is electrically connected to the signal input terminal, and the output terminal is electrically connected to the input terminal of the IIR filter. Each output terminal of the IIR filter is electrically connected to the input terminal of the corresponding frequency band limiting processing circuit. The FIR filter is used to filter the original audio signal. The IIR filter is used to perform frequency division processing on the filtered original audio signal to generate multiple first audio signals.

5. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 3, characterized in that, When there are multiple FIR filters, the input terminal of the IIR filter is electrically connected to the signal input terminal, and each output terminal is electrically connected to the input terminal of the corresponding FIR filter; the output terminal of each FIR filter is electrically connected to the corresponding frequency band limiting processing circuit; the IIR filter is used to divide the original audio signal to obtain multiple first audio signals; the FIR filter is used to filter each first audio signal.

6. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 1, characterized in that, The signal processing device with multi-channel frequency division and independent amplitude limiting includes a passive frequency divider and a multi-channel speaker enclosure; wherein, the input terminal of the passive frequency divider is electrically connected to the output terminal of the power amplifier circuit through the signal output terminal, and each output terminal is electrically connected to the corresponding speaker unit of the multi-channel speaker enclosure, for dividing the second audio signal to generate multiple second audio signals and outputting them to the corresponding speaker units of the multi-channel speaker enclosure respectively.

7. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 6, characterized in that, The passive crossover has at least two output terminals; when the multi-way speaker includes a tweeter unit and a mid-bass driver unit, and the passive crossover has two output terminals, the two output terminals of the passive crossover are electrically connected to the tweeter unit and the mid-bass driver unit of the multi-way speaker, respectively; when the multi-way speaker includes a tweeter unit, a midrange driver unit, and a woofer unit, and the passive crossover has three output terminals, the three output terminals of the passive crossover are electrically connected to the tweeter unit, the midrange driver unit, and the woofer unit of the multi-way speaker, respectively.

8. The signal processing device with multi-channel frequency division and independent amplitude limiting according to claim 1, characterized in that, The frequency band limiting processing circuit comprises N circuits, where N is a natural number greater than or equal to 2.

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