KR100355414B1 - Record/play apparatus of wireless microphone - Google Patents

Abstract

The disclosed recording / playback apparatus receives and outputs recording and reproduction by receiving a voice signal transmitted through a wireless microphone.

Transmitter converts voice signal input through microphone into MP3 voice signal, FEC encodes it, modulates it into high frequency signal and transmits it.Receives transmitted signal from transmitter and converts it to original voice signal by FEC decoding and MP3 decoding. And a recording / reproducing means for recording and reproducing the FEC decoded signal. The receiving unit records and reproduces and outputs an MP3 audio signal to the recording / reproducing means without deteriorating the audio signal even after a long time. You can record and output clearly.

Description

Record / play apparatus of wireless microphone

The present invention converts and transmits a voice signal input through a microphone to a high frequency signal, and stores a voice signal received from a wireless microphone that receives the high frequency signal of the transmitted voice signal, converts it into an original voice signal, and outputs the converted voice signal. The present invention relates to a device for recording / playing back a wireless microphone.

In general, a microphone device is widely used to allow many people to listen to a voice signal.

The microphone device converts a user's voice signal into an electrical signal through a microphone, amplifies it with an amplifier, and outputs the same to a speaker. I can hear this.

The microphone device includes a wired method and a wireless method.

The wired method connects a microphone and an amplification device to a connection line so that the audio signal output from the microphone is input to the amplification device through the connection line, while the configuration is simple, while the user is limited by the length of the connection line. It is used a lot in place to let you use.

In the wireless method, the microphone and the transmitter are connected to convert the microphone's input signal into a high frequency signal, and the transmitter transmits the high frequency signal, which is received by the receiving device, converted into an original voice signal, and then amplified and output to the speaker. There is a wireless microphone unit.

The wireless microphone device is a user only need to carry only a microphone and a transmitter without connecting a connection line, and since the user's movement is not limited, it is widely used in stage acting and lectures requiring free movement.

The wireless microphone device is an analog system, modulates and transmits an audio signal input through a microphone to an FM signal, and receives and amplifies the FM signal transmitted by the FM receiver.

However, the analog system modulates a voice signal into an FM signal, transmits and receives a signal, and outputs the voice signal. As a result, a lot of noise is mixed into the voice signal due to interference of radio waves, and thus the voice signal cannot be output clearly.

Therefore, in recent years, a digital method has been widely used. The input voice signal is converted into a digital signal, and the converted digital voice signal is modulated and transmitted into a high frequency signal, and the receiving device receives the transmitted high frequency signal and converts it into a digital voice signal. The demodulated and converted demodulated digital audio signals are converted into analog audio signals and then amplified and output.

In such a microphone apparatus, conventionally, an analog audio signal to be received and output is input to a deck unit or the like to record and reproduce on a recording medium such as an audio tape.

Therefore, when a long time has elapsed, there is a problem in that the recorded voice signal is degraded due to sagging of the recording medium.

Accordingly, an object of the present invention is to provide a recording / playback means, and to record and play back the FEC-decoded MP3 audio signal to the recording / playback means to maintain the sound quality even after a long time recording / playback of a wireless microphone. To provide a device.

According to the recording / reproducing apparatus of the wireless microphone of the present invention for achieving the above object, the transmitter converts the voice signal input through the microphone into an MP3 voice signal, encodes the FEC, modulates the signal into a high frequency signal, and sends the transmitter. The receiver receives the FEC decoding and MP3 decoding signal, converts it into the original audio signal, and outputs the signal. The recording / reproducing means records and reproduces the FEC decoded signal so that the voice signal deteriorates even after a long time. Record and output cleanly without

And the transmitting unit; An MP3 voice encoder for encoding a voice signal of the microphone input through the microphone interface unit into an MP3 signal; An FEC encoder for FEC encoding the output signal of the MP3 voice encoder; A modulator for modulating the output signal of the FEC encoder into a carrier signal; A high frequency modulator for modulating the output signal of the modulator into a high frequency signal; A power amplifier for amplifying the output signal of the high frequency modulator and transmitting the amplified signal to the air through an antenna; And a control unit controlling an encoding operation of the MP3 voice encoder and the FEC encoder, and the receiving unit; A low noise amplifier for low noise amplifying a high frequency signal transmitted by the transmitter and received through an antenna; A high frequency demodulator for demodulating a high frequency signal amplified by the low noise amplifier to detect a spread signal; A demodulator for demodulating a spread signal demodulated in the high frequency demodulator to remove a carrier wave; An FEC decoder for FEC decoding the output signal of the demodulator and converting the signal into an MP3 signal; An MP3 voice decoder which decodes the output signal of the FEC decoder and converts it into an original voice signal; A voice interface unit for outputting a voice signal decoded by the MP3 voice decoder; An oscillator which oscillates and outputs an oscillation signal; A PLL circuit for stabilizing an output signal of the oscillator; And a control unit for controlling the operation of the FEC decoder and the MP3 voice decoder according to the output signal of the PLL circuit and displaying the operation state on the display unit.

In addition, the transmitting unit; An MP3 voice encoder for encoding a voice signal of the microphone input through the microphone interface unit into an MP3 signal; An FEC encoder for FEC encoding the output signal of the MP3 voice encoder; A modulator for modulating the output signal of the FEC encoder into a carrier signal; A PN spreading unit configured to PN spread the output signal of the modulator; A high frequency modulator for modulating the output signal of the PN spreading unit into a high frequency signal; A power amplifier for amplifying the output signal of the high frequency modulator and transmitting the amplified signal to the air through an antenna; And a control unit controlling encoding operations of the MP3 voice encoder and the FEC encoder, and controlling a PN spreading operation of the PN spreading unit. A low noise amplifier for low noise amplifying a high frequency signal transmitted by the transmitter and received through an antenna; A high frequency demodulator for demodulating a high frequency signal amplified by the low noise amplifier to detect a spread signal; A PN spreading unit which despreads the spread signal demodulated by the high frequency demodulator and converts the spread signal into an original signal; A demodulator for demodulating an output signal of the PN spreading unit to remove a carrier; An FEC decoder for FEC decoding the output signal of the demodulator and converting the signal into an MP3 signal; An MP3 voice decoder which decodes the output signal of the FEC decoder and converts it into an original voice signal; A voice interface unit for outputting a voice signal decoded by the MP3 voice decoder; An oscillator which oscillates and outputs an oscillation signal; A PLL circuit for stabilizing an output signal of the oscillator; And a controller for controlling the operations of the PN despreading unit, the FEC decoder, and the MP3 voice decoder according to the output signal of the PLL circuit, and displaying the operation state on the display unit.

1 is a circuit diagram showing the configuration of an embodiment of a transmitter according to the recording / playback apparatus of the present invention,

2 is a circuit diagram showing the configuration of an embodiment of a receiver according to the recording / playback apparatus of the present invention,

3 is a circuit diagram showing the configuration of another embodiment of a transmitter according to the recording / playback apparatus of the present invention;

4 is a circuit diagram showing the configuration of another embodiment of a receiver according to the recording / playback apparatus of the present invention.

* Description of the symbols for the main parts of the drawings *

10: microphone 11: microphone interface

12: MP3 voice encoder 13: FEC encoder

14 modulator 15 high frequency modulator

16: power amplifier 17, 20: antenna

18, 33: control unit 19: PN spreading unit

21: low noise amplifier 22: high frequency demodulator

23: demodulator 24: FEC decoder

25: MP3 stream memory 26: switching unit

27: voice voice decoder 28: voice interface unit

29 oscillator 30 PLL circuit

31: command input unit 33: display unit

33: control unit 34: PN spreading unit

Hereinafter, a recording / playback apparatus of a wireless microphone of the present invention will be described in detail with reference to the accompanying drawings.

1 is a circuit diagram showing an embodiment of a transmitter in a wireless microphone according to the recording / playback apparatus of the present invention.

As shown therein, a microphone interface unit 11 for inputting a voice signal through the microphone 10 and an MP3 voice encoder 12 for encoding a voice signal input through the microphone interface unit 11 into an MP3 voice signal. And an FEC encoder 13 for encoding the output signal of the MP3 voice encoder 12 and a Forward Error Correction (FEC), a modulator 14 for modulating the output signal of the FEC encoder 13 into a carrier signal, and A high frequency modulator 15 for modulating the output signal of the modulator 14 into a high frequency signal, a power amplifier 16 for amplifying the output signal of the high frequency modulator 15 and transmitting the amplified signal to the air through the antenna 17; An encoding operation of the MP3 voice encoder 12 and the FEC encoder 13 is configured by the controller 18.

However, the FEC encoded by the FEC encoder 13 is to prevent the loss of data in the transmission channel after compressing and restoring the voice data in real time as is well known. FEC with variable structure is used. If the maximum number of errors that can be corrected is N for transmitted messages and T for error correction capability, N-2T surplus terms should be used and can be used flexibly according to BER (Bit Error Rate). That is, the necessary parameters can be recorded and used in the internal register of the FEC encoder 13 according to the channel characteristics. The FEC encoder 13 alternates to buffers 1 and 2 using a double buffer structure therein. FEC processing of data in real time by storing the data. Thus, for example, if data is stored in buffer 1 and then data is stored in buffer 2, the FEC arithmetic processing first executes the data stored in buffer 1 to process the data stably. According to an embodiment of the present invention, a voice signal converted from the microphone 10 into an electrical signal is input to the MP3 voice encoder 12 through the microphone interface unit 11 and is encoded as an MP3 voice signal under the control of the controller 18. .

The MP3 voice signal encoded by the MP3 voice encoder 12 is FEC encoded by the control unit 18 in the FEC encoder 13 and modulated into a carrier signal by the modulator 14.

The signal modulated by the carrier signal by the modulator 14 is modulated by the high frequency modulator 15 into a high frequency signal, amplified by the power amplifier 16, and then transmitted to the air through the antenna 17.

2 is a circuit diagram showing an embodiment of a receiver in a wireless microphone according to the recording / playback apparatus of the present invention.

As shown therein, a low noise amplifier 21 for low noise amplifying the high frequency signal transmitted by the transmitter and received through the antenna 20 and a high frequency demodulator 22 for demodulating the high frequency signal amplified by the low noise amplifier 21. And a demodulator 23 for removing carriers from the signal demodulated by the high frequency demodulator 22, an FEC decoder 24 for FEC decoding the output signal of the demodulator 23 and converting it into an MP3 audio signal, and the FEC MP3 stream memory 25, which is a recording / reproducing means for storing and outputting the output signal of decoder 24, and switching section 26 for selectively outputting the output signal of FEC decoder 24 or MP3 stream memory 25. ), An MP3 voice decoder 27 for decoding the MP3 voice signal selectively outputted by the switching unit 26 and converting the MP3 voice signal into an original voice signal, and a voice for outputting the voice signal decoded by the MP3 voice decoder 27. Interface A oscillator 29 for oscillating and outputting an oscillation signal, a phase locked loop (PLL) circuit 30 for stabilizing an output signal of the oscillator 29, a recording command according to a user's operation, A command input unit 31 for inputting a reproduction command and controlling the decoding operation of the FEC decoder 24 and the MP3 audio decoder 27 according to the output signal of the PLL circuit 30, and the command input unit 31; Control unit 32 for controlling the recording / playback of the MP3 stream memory 25 and the switching operation of the switching unit 26 in accordance with the operation command of the display unit 33 to display the operation status.

In one embodiment of the receiver of the present invention configured as described above, the receiver of the wireless microphone device, the oscillator 29 oscillates to output the oscillation signal, the output oscillation signal is stabilized through the PLL circuit 30, the control unit 32 The control unit 32 uses this input oscillation signal for demodulation of the signal transmitted by the transmitter.

The high frequency signal transmitted by the transmitter is received through the antenna 20 to low noise amplification by the low noise amplifier 21, high frequency demodulation by the high frequency demodulator 22, and demodulated by the demodulator 23 to remove the carrier signal.

The signal demodulated by the demodulator 23 and the carrier signal is removed is FEC decoded by the FEC decoder 25 under the control of the controller 31 to detect the MP3 audio signal.

In this state, when the user operates the command input unit 31 to perform a recording command, the control unit 33 controls the MP3 stream memory 25 according to the recording command to output the MP3 audio signal decoded by the FEC decoder 24. The MP3 stream is stored in the memory 25.

When the MP3 audio signal is recorded in the MP3 stream memory 25, the control unit 33 controls the switching unit 26 to select an output signal of the FEC decoder 24, which is output from the FEC decoder 25. As described above, the MP3 voice signal is stored in the MP3 stream memory 25 and input to the MP3 voice decoder 27 through the switching unit 26 to be decoded and converted into the original analog voice signal.

The analog voice signal output from the MP3 voice decoder 26 is output through the voice interface unit 27, and the output analog voice signal is amplified through an amplifier (not shown) and then output to the speaker. .

In this way, when a user operates the command input unit 31 to play a playback command while a predetermined MP3 audio signal is recorded in the MP3 stream memory 25, the controller 33 controls the switching unit 26 according to the playback command. The controller 33 selects an output signal of the MP3 stream memory 25 and controls the controller 33 to output a predetermined MP3 audio signal in which the MP3 stream memory 25 is stored.

Then, the MP3 stream memory 25 outputs the stored MP3 voice signal, and the output MP3 voice signal is input to the MP3 voice decoder 27 through the switching unit 26 to be decoded and converted into an original analog voice signal. .

The analog voice signal output from the MP3 voice decoder 26 is output through the voice interface unit 27.

3 is a circuit diagram showing the configuration of another embodiment of a transmitter according to the recording / playback apparatus of the present invention.

As shown therein, another embodiment of the transmitter of the present invention is a PN spreading unit for PN spreading the output signal of the modulator 14 between the modulator 14 and the high frequency modulator 15 and inputting the same to the high frequency modulator 15. (19) is provided.

In another embodiment of the present invention configured as described above, a signal modulated by the modulator 14 is input to the PN spreading unit 15, and the PN spreading unit 15 is input under the control of the controller 19. The signal is spread with pseudo noise, and the spread signal is modulated by the high frequency modulator 16 into a high frequency signal, amplified by the power amplifier 17 and then sent out to the air through the antenna 18.

4 is a circuit diagram showing the configuration of another embodiment of a receiver according to the recording / playback apparatus of the present invention.

As shown therein, another embodiment of the receiver includes a PN despreading unit which despreads the spread signal demodulated by the high frequency demodulator 22 to convert the spread signal into an original signal and inputs the demodulated signal to the demodulator 23. 23 is provided.

According to another embodiment of the receiver of the present invention configured as described above, the PN despreading unit 34 despreads and outputs the signal demodulated by the high frequency demodulator 22 under the control of the controller 31.

That is, the PN despreading unit 34 removes the pseudo noise while matching the synchronization and demodulator 23 by knowing the pattern and the synchronization of the pseudo noise spreading the signal input from the PN spreading unit 19 of the transmitter. Will output

Here, the noise is removed using the phase difference as in the conventional method. On the other hand, if the voice signal converted by the microphone 10 is sampled into 16-bit digital data in the transmitter of FIG. In order to encode an MP3 voice signal, a subband filter operation is performed, and after 576 sample data are stored, a psychoacoustic operation is performed. When the encoding is completed in the MP3 format, one frame of 396 bytes is stored. The calculated MP3 coded data is divided by a predetermined byte unit and FEC calculation is performed, and a certain surplus term is added to the data of the calculation result and transmitted. However, the added surplus terms can be changed flexibly according to channel characteristics. Generally, the more surplus terms, the higher the reliability of the transmitted data, but the transmission speed of the data is lowered. The PN disk of the receiver of FIG. The signal reconstructed from the reading unit 34 is arithmetic processed by the FEC decoder 24. At this time, the original MP 3 frame data is corrected by decoding in a predetermined byte unit. The modified data is input to the MP3 voice decoder 27 to be processed and finally restored to a voice signal.

As described above, according to the present invention, by storing, reproducing and outputting the MP3 voice signal received and decoded by the wireless microphone, the voice signal can be clearly reproduced and output without deterioration even after a long period of time.

Claims (3)

A transmitter for converting a voice signal input through a microphone into an MP3 voice signal, performing FEC encoding, modulating the voice signal into a high frequency signal, and transmitting the same; And Receiving unit for receiving the transmission signal of the transmitter, FEC decoding and MP3 decoding to convert the original voice signal and outputs; And the receiving unit includes recording / reproducing means for recording and reproducing the FEC decoded signal. The apparatus of claim 1, wherein the transmitting unit; An MP3 voice encoder for encoding a voice signal of the microphone input through the microphone interface unit into an MP3 signal; An FEC encoder for FEC encoding the output signal of the MP3 voice encoder; A modulator for modulating the output signal of the FEC encoder into a carrier signal; A high frequency modulator for modulating the output signal of the modulator into a high frequency signal; A power amplifier for amplifying the output signal of the high frequency modulator and transmitting the amplified signal to the air through an antenna; And A control unit for controlling the encoding operation of the MP3 voice encoder and the FEC encoder, The receiving unit; A low noise amplifier for low noise amplifying a high frequency signal transmitted by the transmitter and received through an antenna; A high frequency demodulator for demodulating a high frequency signal amplified by the low noise amplifier to detect a spread signal; A demodulator for demodulating a spread signal demodulated in the high frequency demodulator to remove a carrier wave; An FEC decoder for FEC decoding the output signal of the demodulator and converting the signal into an MP3 signal; An MP3 voice decoder which decodes the output signal of the FEC decoder and converts it into an original voice signal; A voice interface unit for outputting a voice signal decoded by the MP3 voice decoder; An oscillator which oscillates and outputs an oscillation signal; A PLL circuit for stabilizing an output signal of the oscillator; And And a control unit for controlling the operation of the FEC decoder and the MP3 audio decoder in accordance with the output signal of the PLL circuit, and for displaying an operation state on a display unit. The apparatus of claim 1, wherein the transmitting unit; An MP3 voice encoder for encoding a voice signal of the microphone input through the microphone interface unit into an MP3 signal; An FEC encoder for FEC encoding the output signal of the MP3 voice encoder; A modulator for modulating the output signal of the FEC encoder into a carrier signal; A PN spreading unit configured to PN spread the output signal of the modulator; A high frequency modulator for modulating the output signal of the PN spreading unit into a high frequency signal; A power amplifier for amplifying the output signal of the high frequency modulator and transmitting the amplified signal to the air through an antenna; And A control unit which controls the encoding operation of the MP3 voice encoder and the FEC encoder and controls the PN spreading operation of the PN spreading unit, The receiving unit; A low noise amplifier for low noise amplifying a high frequency signal transmitted by the transmitter and received through an antenna; A high frequency demodulator for demodulating a high frequency signal amplified by the low noise amplifier to detect a spread signal; A PN spreading unit which despreads the spread signal demodulated by the high frequency demodulator and converts the spread signal into an original signal; A demodulator for demodulating an output signal of the PN spreading unit to remove a carrier; An FEC decoder for FEC decoding the output signal of the demodulator and converting the signal into an MP3 signal; An MP3 audio decoder which decodes the output signal of the FEC decoder and converts it into an original audio signal; A voice interface unit for outputting a voice signal decoded by the MP3 voice decoder; An oscillator which oscillates and outputs an oscillation signal; A PLL circuit for stabilizing an output signal of the oscillator; And And a control unit for controlling the operation of the PN spreading unit, the FEC decoder, and the MP3 voice decoder according to the output signal of the PLL circuit, and displaying the operation state on the display unit.