KR100882828B1 - Wireless Multi-channel Speaker System Based UWB For Transmitting 3-Dementional Sound - Google Patents

Abstract

The present invention relates to a wireless multi-channel speaker system having a three-dimensional stereoscopic effect (surrounding effect). More particularly, the present invention relates to a high-quality sound and three-dimensional system through securing a bandwidth for a multi-channel based on a broadband ultra wide band (UWB). The present invention relates to a wireless multi-channel speaker system capable of transmitting voice information having a three-dimensional effect (a surround effect).

UWB, Wireless, Multichannel, Speakers, OOK, PSK

Description

Wireless Multi-Channel Speaker System for 3-D Stereo Sound Transmission {Wireless Multi-channel Speaker System Based UWB For Transmitting 3-Dementional Sound}

1 is a block diagram of a wireless multi-channel speaker system according to a preferred embodiment of the present invention, Figure 2 is a detailed block diagram of the figure.

3 is a detailed block diagram of a speaker receiver for each channel by OOK modulation according to an exemplary embodiment of the present invention.

4 is a detailed block diagram of a speaker receiver for each channel by PSK modulation according to an embodiment of the present invention.

5 is a waveform diagram schematically illustrating a pattern transition of a monopolar code signal during OOK modulation according to the present invention.

6 is a waveform diagram schematically illustrating a state in which carrier waves of a PSK modulated signal are removed according to the present invention.

<Description of the symbols for the main parts of the drawings>

10: audio device transmitter 110: encoder

120: mux 130: modulator

140: transmit antenna 20: speaker receiver for each channel

210: receiving antenna 220: BPF

230: decoder 231: envelope detector

232: matched filter 233: determiner

234: carrier buffer 240: amplifier

The present invention relates to a wireless multi-channel speaker system, and more particularly, to transmit high-quality voice information with three-dimensional stereoscopic effect (surrounding effect) by securing bandwidth for multi-channels based on a wide ultra wide band (UWB). A wireless multichannel speaker system is possible.

With the development of technology, the wired speaker system is being converted into a wireless speaker system, and a single-channel speaker is implemented in multiple channels such as 5. 1 channel, 7. 1 channel, and 9.1 channel. Is being carried out continuously.

As the number of channels increases, high quality 3D sounds can be realized. Therefore, a need arises for hundreds of channels of speaker devices.

However, the conventional wireless speaker system uses wireless communication technologies (Bluetooth, Wireless LAN, Binary CDMA (B-CDMA), etc.) applied in unlicensed bands such as 2.4GHz ISM band or 5GHz UNII band. By using a method of wireless transmission from the audio device to the speaker, but the conventional wireless method as described above uses a narrow band frequency band of several tens of MHz or less per channel as compared to UWB, not only can not provide sufficient bandwidth, Due to the low transmission speed and many problems such as collision with other systems in the channel or reduction of collision speed due to collision avoidance, there are limitations in the application of multi-channel speakers for perfect 3D stereo sound.

In addition, the conventional wireless method has a problem that it is difficult to implement high quality sound because the audio signal is distorted by the interference of the signal for implementing the multi-channel speaker and the original sound is not properly transmitted through the speaker.

In order to solve the above problems, an object of the present invention is to transmit audio data through a multi-channel by the ultra-wideband (UWB), and to remove the interference of the signal to deliver high-quality sound three-dimensional To provide a wireless multi-channel speaker system capable of stereo sound implementation of.

In order to achieve the above object, a UWB-based wireless multi-channel speaker system for three-dimensional stereophonic sound transmission according to the present invention encodes and multiplexes an audio signal of a multi-channel (1 to N-channel) and performs a specific frequency band of UWB. Spreads and modulates the carrier frequency and transmits the modulated signal through a specific frequency band for the signal received from the audio device transmitter and the audio device transmitter, and removes a carrier component from the output signal. And a speaker receiver for outputting audio by decoding only the channel signal to restore audio data.

The audio device transmitter may include an encoder for encoding and encoding a multi-channel audio signal for each channel, a mux for multiplexing the encoded signal, and a modulator for spreading and modulating the multiplexed signal on a carrier frequency of a specific frequency band. And a transmission antenna for transmitting the modulated signal.

The encoder is characterized by generating a spreading code having one point orthogonal or ZCD characteristic.

In addition, the modulator multiplies the carrier carrier having a specific frequency band of the UWB to perform OOK (On-Of Keying) modulation or PSK (Phase Shift Keying) modulation.

The carrier carrier is a chaotic source that changes randomly with time.

In addition, the channel-specific speaker receiver according to the present invention is a bandpass filter (BPF) for passing through a specific frequency band for the reception antenna for receiving the modulated signal transmitted from the audio device transmitter and the signal received from the audio device transmitter (BPF) And a decoder which removes a carrier component from the output signal and decodes only a corresponding channel signal, and an amplifier which amplifies and outputs the restored audio data.

The decoder performs a correlation process on an envelope detector that removes a carrier component of the received signal and a decoded signal, and compares a matched filter that derives an autocorrelation peak value, and compares the autocorrelation peak value with a threshold. And a determiner for restoring and generating the audio signal.

The decoder may further include a carrier buffer in which the same carrier frequency is stored to remove the carrier frequency when the audio device transmitter is spread-modulated by a PSK scheme.

The carrier buffer stores a carrier frequency corresponding to “1” and a carrier frequency corresponding to “−1”, and removes a carrier frequency component by multiplying the carrier frequency by a signal output through a bandpass filter. It features.

Here, the carrier frequency stored in the carrier buffer is characterized in that the chaotic source.

Hereinafter, the specific configuration and operation of the present invention will be described in detail with reference to the drawings and the embodiments. Here, although only a block diagram of one channel-specific speaker (Ch1) receiving unit among the multi-channel (1-N) channel-specific speaker receiving units is shown in the drawing, the remaining channel-specific speaker receiving unit is not shown. It is obvious that they have the same block diagram.

1 is a block diagram of a wireless multi-channel speaker system according to a preferred embodiment of the present invention, Figure 2 is a detailed block diagram of the figure. Here, FIG. 1 illustrates that an audio device and an audio device transmitter, a channel-specific speaker, and a channel-specific speaker receiver are separately configured for convenience of description. It is obvious that it can be installed in the installation.

The audio device is not limited to a device providing only audio, but may include any AV device capable of supporting a multi-channel method such as a computer terminal, a TV, and various display terminals.

1 and 2, the wireless multi-channel speaker system according to the present invention includes an audio device transmitter 10 and a speaker receiver 20 for each channel.

The audio device transmitter 10 encodes and multiplexes an audio signal of multiple channels (1 to N channels), spreads the modulated signal on a carrier frequency of a specific frequency band of the UWB, and transmits the modulated signal. Here, the multichannels (1 to N channels) do not need to limit the upper limit because the UWB band can provide a wide bandwidth, so that all speaker systems that can be composed of two or more channels will be defined as multichannels. .

In addition, the speaker receiver 20 for each channel outputs the signal received from the audio device transmitter by passing only a specific frequency band, removes a carrier component from the output signal, and decodes only the corresponding channel signal to decode the audio data. Restore and output audio.

More specifically, the audio device transmitter 10 includes an encoder 110 for encoding a multi-channel audio signal, a mux 120 for multiplexing the encoded signal, and a carrier frequency of a specific frequency band to the multiplexed signal. It may be configured to include a modulator 130 for spreading modulation and a transmission antenna 140 for transmitting the modulated signal.

The audio device transmitter 10 converts an analog audio signal generated from an audio device into a digital audio signal by an ADC (not shown), and is encoded by an encoder 110 into an audio codec for each channel. In this case, the encoding may be encoded in any form as long as it is a spreading code supporting OOK modulation or PSK modulation.

For example: 5. For 1-channel speakers, 2-channel left and right stereo channel, 2-channel left and right surround channel, single center channel, and low frequency enhancement. It may be configured as a low frequency enhancement channel (LFE), and the encoder 110 performs encoding so that an audio signal is transmitted to a speaker corresponding to each channel.

Here, the encoder 110 may generate information data generated by multiplying the encoded signal by a confidence code having a one-point orthogonal or zero correlation duration (ZCD) characteristic.

The spreading code having a single point orthogonal or ZCD characteristic has a small value negligible in cross correlation with the side love (Sidelobe) of the autocorrelation function for a predetermined time interval (maximum N-1 chip) around the autocorrelation peak point. Or zero, autocorrelation side-love is completely zero, or cross-correlation between codes is completely zero in all time delay intervals, and the processing gain is variable. A spreading code that can be done.

The spreading code having a single point orthogonal or ZCD characteristic eliminates the effects of MPI (Multi-Path Interference) or MAI (Multi-Access Interference), which is an interference problem in the UWB environment. The efficiency of communication can be increased by reducing the

Hereinafter, audio data for each channel encoded by the encoder 110 will be defined as information data.

The mux 120 is responsible for multiplexing to wirelessly transmit the encoded information data through the encoder.

In addition, the modulator 130 plays a role of spread-modulating the multiplexed signal on a carrier frequency of a specific frequency band. Here, since the UWB (Ultra Wide Band) can use a wide frequency band from 3.1 GHz to 10.6 GHz, the carrier frequency can be arbitrarily selected from the UWB band.

More specifically, the modulator 130 performs OOK (On-Off Keying) or PSK (Phase Shift Keying) modulation by multiplying the multiplexed signal through a predetermined switching circuit to a carrier carrier having a specific frequency band of UWB. . The carrier may be a chaotic source that changes randomly with time. Here, PSK includes BPSK and QPSK.

The OOK modulation transmits a signal in the "On" state, performs an operation of eliminating the signal level in the "Off" state, and the above operation can be simply implemented through a switching circuit. According to the operation of the OOK modulator 150 as described above, the asynchronous detection can be easily implemented in the speaker receiver for each channel. In addition, the OOK modulation may be defined as a low-speed modulation since it is a monopole modulation method represented by "1" and "0".

For the OOK modulation, the modulator spreads the unipolar information data (FIG. 5A) encoded by the encoder into a unipolar spreading sequence.

Here, the generated monopolar spreading code signal is as shown in (b) of FIG. 5, and the signal output through the modulator is as shown in (c) of FIG.

On the other hand, PSK modulation does not have an "Off" state, and since it is a bipolar modulation method of "1" and "-1" type can be defined as high-speed modulation.

Here, when the encoder 110 generates a code having a single point orthogonal or ZCD characteristic, the OOK modulation generates a monopolar spreading code (0, 1), and the PSK modulation is a bipolar spreading code that is a binary or ternary spreading code. Will generate (-1, 1).

The modulated signal is wirelessly transmitted through the transmission antenna 140 and received by the speaker receiver 20 for each channel.

The channel-specific speaker receiver 20 according to the present invention is a bandpass filter for outputting only a specific frequency band for the reception antenna 210 for receiving the modulated signal transmitted from the transmitting antenna and the signal received from the audio device transmitter. And a decoder 230 for removing a carrier component from the output signal and decoding only a corresponding channel signal, and an amplifier 240 for amplifying and outputting the restored audio signal.

More specifically, the bandpass filter 220 serves to pass only a specific frequency band among the signals received by the reception antenna 210. Therefore, only the spread signal carried on the carrier of a specific frequency band passes through the bandpass filter 220.

The decoder 230 is responsible for removing a carrier component from a signal output through the bandpass filter and decoding only a corresponding channel signal among the multiplexed signals.

3 is a detailed block diagram of a speaker receiver for each channel by OOK modulation according to an exemplary embodiment of the present invention.

Referring to FIG. 3, the decoder 230 performs a correlation process on an envelope detector 231 for removing a carrier component from the output signal and a signal from which the carrier component is removed to match an autocorrelation peak value. And a filter 232 and a determiner 233 for restoring and generating the transmitted audio signal by comparing the autocorrelation peak value with a threshold.

In this case, since the asynchronous detection is possible when the audio device transmitter 10 transmits the signal by OOK modulation, only the envelope detector 231 may remove all the specific frequency band components existing in the carrier. The unipolar spreading code pattern signal output from the envelope detector 230 is as shown in FIG.

4 is a detailed block diagram of a speaker receiver for each channel by PSK modulation according to an embodiment of the present invention.

Referring to FIG. 4, since asynchronous detection is not possible when transmitting with PSK modulation, carrier components cannot be removed using only the envelope detector 231, and thus, a carrier buffer 234 storing a carrier carrier should be further included.

6 is a waveform diagram schematically illustrating a state in which carrier waves of a PSK modulated signal are removed according to the present invention.

Referring to FIG. 6, the carrier buffer 234 stores carrier carriers corresponding to “1” and “−1”, and removes a carrier component by multiplying the carrier carrier by a signal input to an envelope detector 231. can do.

The signal output from the envelope detector is input to the matched filter 232, and the matched filter performs a correlation process using a reference code of its own to derive a correlation peak value. Here, the reference code may be configured to include an identification code for identifying the multi-channel speaker.

The correlation peak value output from the matching filter 232 is input to the determiner 233, and the determiner 233 receives the correlation peak value and compares it with the threshold, and when the information is equal to or greater than the threshold, information data is " If it is determined to be "1" or less, then the function of "0" is performed to restore the audio signal.

The restored audio signal is amplified by the amplifier unit 240 and output through the speaker.

As described above, the wireless multi-channel speaker system according to the present invention can use a wide frequency band from 3. 1 GHz to 10.6 GHz based on UWB, which can significantly solve the frequency shortage problem of the wireless multi-channel speaker. Occurs.

In addition, the data transmission speed is faster than the conventional wireless speaker method, and the signal distortion can be reduced, resulting in an excellent effect of providing high quality sound.

Although the detailed description of the present invention described above has been described with reference to the preferred embodiment of the present invention, the protection scope of the present invention is not limited to the above embodiment, and those skilled in the art will appreciate It will be understood that various modifications and changes can be made in the present invention without departing from the spirit and scope of the invention.

Claims (10)

An audio device transmitter for encoding and multiplexing an audio signal of multiple channels (1 to N channels), spreading modulation on a carrier frequency of a specific frequency band of a UWB, and transmitting the modulated signal; A speaker receiving unit for outputting audio by outputting only a specific frequency band to a signal received from the audio device transmitter, removing a carrier component from the output signal, decoding only a corresponding channel signal, and restoring audio data to output audio. Including, The audio device transmitter comprises: an encoder for encoding and encoding a multi-channel audio signal for each channel; A mux for multiplexing the encoded signal; A modulator configured to spread-modulate the multiplexed signal on a carrier frequency of a specific frequency band; UWB-based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that it comprises a transmission antenna for transmitting the modulated signal. delete The method of claim 1, The encoder UWB based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that for generating a spreading code of one point orthogonal or ZCD characteristics. The method of claim 1, The modulator A UWB-based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that multi-carrier carrier having a specific frequency band of the UWB multiplied by the OOK (On-Of Keying) modulation or PSK (Phase Shift Keying) modulation. The method of claim 4, wherein The carrier carrier is UWB-based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that the chaotic source randomly changes over time. An audio device transmitter for encoding and multiplexing an audio signal of multiple channels (1 to N channels), spreading modulation on a carrier frequency of a specific frequency band of a UWB, and transmitting the modulated signal; A speaker receiving unit for outputting audio by outputting only a specific frequency band to a signal received from the audio device transmitter, removing a carrier component from the output signal, decoding only a corresponding channel signal, and restoring audio data to output audio. Including, The channel-specific speaker receiver comprises: a reception antenna for receiving a modulated signal transmitted from the audio device transmitter; A band pass filter configured to pass only a specific frequency band and output the signal received from the audio device transmitter; A decoder which removes a carrier component from the output signal and decodes only a corresponding channel signal; UWB-based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that it comprises an amplifier for amplifying and outputting the restored audio data. The method of claim 6, The decoder An envelope detector for removing a carrier component from the received signal; A matched filter for performing correlation processing on the decoded signal to derive an autocorrelation peak value; And a determiner for reconstructing and generating the transmitted audio signal by comparing the autocorrelation peak value and a threshold value. The method of claim 7, wherein The decoder In the case of spread modulation by PSK (Phase Shift Keying) in the audio device transmitting unit, a UWB-based wireless multi-carrier for three-dimensional stereophonic transmission, further comprising a carrier buffer in which the same carrier frequency is stored to remove the carrier frequency. Channel speaker system. The method of claim 8, The carrier buffer  A three-dimensional stereoscopic feature characterized by storing a carrier frequency corresponding to "1" and a carrier frequency corresponding to "-1", and removing a carrier frequency component by multiplying the carrier frequency by a signal output through a bandpass filter UWB based wireless multi-channel speaker system for sound transmission. The method according to claim 8 or 9, The carrier frequency stored in the carrier buffer is UWB based wireless multi-channel speaker system for three-dimensional stereophonic transmission, characterized in that the chaotic source.

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