KR20110030784A - Method for communicating data over voice channel - Google Patents

Abstract

PURPOSE: A method for communicating data over a voice channel is provided to prolong a communication range using the voice channel for performing communication. CONSTITUTION: A speech data(301) is transmitted to a mobile phone(660) from a vehicle terminal unit(750) through a wireless mobile communication network. The speech data is decoded in a vocoder(662). The decoded data is transmitted to a vehicle terminal part(650) through a Bluetooth module(661). If data communication is needed, a C2CVM modem(602) of the vehicle terminal part and a C2CVM modem(702) of another vehicle terminal part are converted into a text mode.

Description

Vehicle-to-vehicle data communication via voice channel {METHOD FOR COMMUNICATING DATA OVER VOICE CHANNEL}

The present invention relates to a wireless data communication system, and more particularly, to an inter-vehicle communication service method for transmitting and receiving digital data through a voice channel of a digital wireless communication network.

The inter-vehicle communication system forms a direct or indirect communication channel between vehicles and transmits and receives data using encoding and decoding algorithms optimized for the communication channel. In the inter-vehicle communication system, a direct communication channel is a vehicle (including a terminal) within a short distance of several hundred meters using an ad hoc network such as Bluetooth, DSRC, Radar, or a special modem. It refers to establishing a communication channel between the vehicle and the terminal (including the terminal). In addition, indirect communication channels include roadside base station RSE (Road Side Entity) and AP (Access Point) for communication modems such as Wireless LAN, Bluetooth, DSRC, and mobile communication defined in 3GPP / 3GPP2 installed in the first vehicle terminal. The first communication channel is established with the service relay system connected to the equipment such as BTS (Base Transceiver Station), and the second communication channel is established with the communication modem of the terminal in the other vehicle through the service relay system. It is a method of forming a communication channel indirectly with another vehicle.

Voice communication systems in digital wireless communication networks employ encoding and decoding algorithms that are optimized for voice characteristics to efficiently and accurately deliver voice. DoV (Data over Voice) modem is a modem that implements a technology for transmitting and receiving data through a voice call channel, while VoIP technology is an IP-based voice call technology. The modem mainly converts speech into digital signals through linear predictive coding algorithms that use the linear characteristics of the speech. In addition, most vocoders have a linear predictive coding algorithm for transforming speech, as well as a separate algorithm for removing non-speech noise or a linear predictive coding algorithm that includes an algorithm for removing noise. Improves its quality.

The DoV modem's linear predictive coding algorithm predicts and evaluates speech characteristics in a certain section according to the linear characteristics of speech, and then condenses the characteristics of the speech. In detail, the intervals having nonlinear characteristics and monotonous characteristics are roughly coded by allocating fewer abbreviated data bits. In addition, in some cases, a change in a section having a nonlinear characteristic and a monotonous characteristic may be canceled by a noise canceling algorithm.

1 is a block diagram illustrating a short range communication system in a general inter-vehicle communication system.

As shown, in-vehicle terminal units 101 and 115 for inter-vehicle communication are Human Machine Interface (HMI) modules 102 and 114, which are interfaces with a user such as a microphone, a speaker, a touchable LCD, and the like, and services that process services between vehicles. Modules 103 and 109, control modules 105 and 111 for converting and processing service data between the service module and the communication module, and ad hoc networks 108 temporarily formed such as DSRC, Bluetooth, Zigbee, and Wireless LAN. It consists of communication modules 107 and 113 which communicate.

In order to transmit the inter-vehicle data in the terminal unit 101 of any vehicle, a user inputs data to be transmitted using the HMI module 102 and the input data is provided by the service module 103 for service processing. 104 to generate communication data 106 for the temporary wireless network 108 through the control module. In addition, the communication data 106 is transmitted to the communication module 113 mounted in the other vehicle terminal 115 via the temporary wireless network 108 via the communication module 107. The transmitted communication data 112 is converted into the service data 110 through the control module 111 and the converted data is transferred to the HMI module 114 by the service module 109 so that the user can check it.

As mentioned above, randomly formed ad hoc wireless networks typically have a communication distance of less than 600 m and specially developed special modems to extend the distance. As another technique for extending the communication distance, there is an example of using the communication with the terminal of the vehicle relaying.

2 is a block diagram illustrating a telecommunication system in a general inter-vehicle communication system.

As shown, any in-vehicle terminal unit 220 that wishes to transmit digital data is generated in the remote vehicle when the communication data 221 is made through the control module 205 for delivery to the remote in-vehicle terminal unit 224. The terminal identification value of the terminal unit 224 is transmitted to the temporary radio network 208 and the terminal unit 222 in the relay vehicle, which is another vehicle in the temporary radio network, is transmitted to another vehicle. The remote in-vehicle terminal unit 224 in which the terminal identification value included in the received communication data 221 of another vehicle is the same as the terminal identification value thereof, controls the received communication data 223 with the control module 211 and the service module. (209), the user passes through the HMI module. As described above, digital data between vehicles is transmitted and received through a dedicated communication module 207 and 213 that can communicate with the temporary wireless network 208.

Digital wireless communication networks are required not only for the delivery of voice but also for the delivery of data in real time. In particular, the voice channel used to transmit voice has a relatively large bandwidth in comparison to other channels in a wireless communication system, and if a data is transmitted using the voice channel, a larger volume of data can be delivered in real time. . However, data that is bounded by random repetitions of 0 and 1 to have a non-linear form is different from speech having a linear characteristic. Due to the difference in data and voice characteristics, data can easily be distorted when the data is encoded and decoded using the DoV modem's linear predictive coding algorithm. Therefore, in order to transmit data using a DoV modem that performs encoding and decoding of speech, a data communication algorithm for preventing distortion in the process of encoding and decoding data is required of the DoV modem.

An object of the present invention is to provide an inter-vehicle data transmission / reception system using a voice channel of a wireless communication network, and connects a vehicle terminal and a mobile phone through Bluetooth and establishes a voice call channel between vehicles using a hands-free service of Bluetooth. Forming and transmitting / receiving data directly between vehicles using DoV technology, implementing encoding module using Multi Array FSK, Multi Array PSK, Multi Tone, Multi Array BPSK, etc. The present invention provides a method of distinguishing voice calls for communication so as to transmit and receive data between vehicles.

The digital data communication system according to an embodiment of the present invention for achieving the above object is a digital data communication system for transmitting a voice signal or digital data between vehicles, each vehicle is a collection of voice for the digital data And a C2CVM modem modulating to include frequency characteristics of consonants. And a transmission / reception module for receiving the output of the terminal through Bluetooth and transmitting and receiving through a voice channel of a mobile communication network.

Preferably, the terminal unit stores the digital data and delivers to the C2CVM modem; A voice codec for converting an input voice signal into a digital signal or converting the digital signal into the voice signal; And a Bluetooth module selectively connected to the service module and the voice codec and for transmitting and receiving the digital data with the transceiving module.

Preferably, the frequency characteristic of the vowel is a result of modulating the digital data using M-ary FSK, M-ary PSK, or M-ary BPSK of low frequency band, and the frequency characteristic of the consonant is Characterized in that the dummy signal is formed through the insertion.

Preferably, the transmission and reception module is connected to the terminal unit Bluetooth module for transmitting and receiving the digital data; A vocoder for converting the Bluetooth module to be suitable for the voice channel; And a mobile communication modem for modulating an output of the vocoder corresponding to the mobile communication network or for demodulating a signal transmitted through the mobile communication network.

Preferably, the mobile communication network is one of CDMA, GSM, WCDWA, Wibro.

In order to extend the communication distance between vehicles, a conventionally developed communication module using a specially developed communication module having a large electric wave energy strength of the communication module or a vehicle terminal relayed in the middle of a vehicle between both ends of an inter-vehicle communication service is implemented. Unlike the present invention, the present invention overcomes the distance limitation of the inter-vehicle communication by constructing a hybrid of a Bluetooth and a broadband mobile communication network, which is a short-range wireless communication, by using a mobile communication network capable of wide area communication services such as CDMA, WCDMA, Wibro, etc. There is an advantage to extend it.

In addition, in the present invention, only the C2CVM module, which is an inter-vehicle communication module and a necessary service module, using voice channels in a mobile phone using a Bluetooth hands-free technology and a mobile communication network owned by most drivers for safe driving during a call By enabling the inter-vehicle communication at all times without having to configure the temporary wireless network by mounting it in the terminal, it is possible to ensure the ease and versatility of system construction using the voice channel of the wireless communication network for the inter-vehicle communication service.

The present invention not only implements an encoding module using Multi Array FSK, Multi Array PSK, Multi Tone, Multi Array BPSK, etc. in order to distinguish between a general voice call and a voice call for data communication. We will build a vehicle-to-vehicle communication service system using voice channel of wireless communication network by adding C2CVM module, an inter-vehicle communication module using voice channel, and necessary service module to Bluetooth hands-free technology and mobile phone.

3 is a block diagram illustrating an inter-vehicle communication system according to an embodiment of the present invention. In particular, the inter-vehicle communication system is characterized by using a Cat to Car Voice Modem (C2CVM) module.

As shown, a driver in a vehicle through the inter-vehicle communication system of the present invention may be provided with various inter-vehicle communication services using the vehicle terminal units 650 and 750 and the mobile phones 660 and 760 installed in the vehicle. The present invention is characterized in that the communication between the vehicle unit 600 and the vehicle terminal (650,750) and the mobile phone (660,760) in the vehicle unit 600 and the other vehicle 700 using the Bluetooth, which is a short-range communication technology, and the vehicle unit 600 and other The vehicle 700 is connected through a mobile communication network 300, such as CDMA, GSM, WCDMA, Wibro.

FIG. 4 is a block diagram illustrating in detail the inter-vehicle communication system illustrated in FIG. 3. In particular, the internal configuration of the vehicle terminal 650 and the other vehicle terminal 750 will be described in detail.

As shown, the vehicle terminal 650 configured in the present invention, unlike the terminal for the inter-vehicle communication, is equipped with a Bluetooth module 607 instead of a modem for wireless communication in the vehicle terminal instead of Bluetooth The PCM data 608 of the voice is exchanged with the mobile phone 660 having the module 661 and the mobile phone 660 receives the PCM data 608 of the voice received from the vehicle terminal 650. The audio data 301 is transmitted through the mobile communication modem 663 by encoding through 662 and transmitted to the other vehicle terminal 750 through the wireless mobile communication network 300. The voice data 302 transferred to the other vehicle terminal 750 is received in the reverse order to the mobile communication modem 763 of the other mobile phone 760 and decoded through the vocoder 762 to decode the Bluetooth of the other mobile phone 760. The module 761 exchanges the PCM data 708 with the Bluetooth module 707 in the other vehicle terminal 750. In addition, the voice data 301 transferred from the other vehicle terminal unit 750 to the mobile phone 660 via the wireless mobile communication network 300 is decoded by the vocoder 662 and the decoded data is the vehicle terminal through the Bluetooth module 661. It is sent to the unit 650.

As such, after the voice call line is connected between the vehicle terminal 650 and the other vehicle terminal 750, the vehicle terminal unit may be changed by the inter-vehicle communication service scenario during the voice call between the user 601 and the other vehicle user 701. 650 or the C2CVM modem 702 of the other terminal 750 and the C2CVM modem 702 of the other vehicle terminal 750 in the text mode by the mode switching scenario when data communication is required from the other vehicle terminal 750. Switch to

Then, the service module 612 service data 611 of the vehicle terminal 650 is transferred to the C2CVM module 602, and the C2CVM modem 602 receiving the service data 611 receives the service data 611 through the text / voice converter 610. The encoded PCM data 609 is transmitted to the Bluetooth module 607 and transmitted to the other vehicle unit 700 through the mobile phone 660 and the mobile communication network 300.

The other vehicle terminal 750 receiving the PCM data 708 decodes it through the text / voice converter 710 of the C2CVM modem 702, and the C2CVM modem 702 performing the decoding process receives the final decoding result. Service data 711 is transferred to the service module 712.

On the contrary, the procedure of transmitting the service data 711 of the other vehicle terminal 750 to the service data 611 of the vehicle terminal 650 is reversed.

When the service data transmission and reception is completed by the above-mentioned service scenario, it is switched to the voice mode again by the mode switching scenario to enable voice communication between the vehicle terminal 650 and the other vehicle terminal 750.

FIG. 5 is a flowchart of a mode switching scenario in the inter-vehicle communication system illustrated in FIG. 3.

As shown, a Bluetooth voice call is formed between the vehicle terminal 650 and another vehicle terminal 750, and a voice call is made between the user 601 and another vehicle user 701 after a service communication line capable of service is connected. It is formed in the voice mode to enable. In this state, the other vehicle terminal 750 connects the call switch 706 such that the call PCM data 708 input from the vehicle terminal 650 is input not only to the other vehicle user 701 but also to the C2CVM modem 702. And input PCM data 708 into the C2CVM modem 702 so that the C2CVM modem 702 can detect the mode switching tone. In this state, the C2CVM modem 602 waits to generate a mode switching tone by the command of the service module 612. (S801)

The service scenario determines whether data transmission or reception is necessary (S802), and if data transmission / reception is not necessary, maintains an existing voice call and monitors whether data transmission / reception is required (S803).

If transmission and reception of data 611 and 711 are necessary, the C2CVM modems 602 and 702 in the vehicle terminal 650 or the other vehicle terminal 750 generate a mode switching tone (S804). The mode switching tone may be performed anywhere in the vehicle terminal 650 and the other vehicle terminal 750. However, for convenience of explanation, the following description will be described taking the case of transmitting the service data 111 from the vehicle terminal 600 to the other vehicle terminal 500 as an example.

When the C2CVM modem 602 in the vehicle terminal unit 650 generates the mode switching tone, the generated mode switching tone is transmitted to the Bluetooth module 607 as PCM data 609 and the mobile phone 660 and the mobile communication network. The vehicle 300 is transferred to the other vehicle terminal unit 750 through the 300. The C2CVM modem 602 generates a mode switching tone and waits for an ACK tone to be input from another vehicle terminal 750. (S805)

The text / voice mode controller 703 in the C2CVM modem 702 of the other vehicle terminal 750 detects this mode switching tone and notifies the service module 712, and the service module 712 receives the other vehicle user 701. The communication path of the call switch 706 is disconnected to prevent voice communication. After that, the C2CVM modem 702 switches to the text mode and generates an ACK tone indicating that the conversion is completed, and hands it to another vehicle mobile phone 760 so that the vehicle terminal 650 knows that the text mode has been switched. 702 informs the service module 712 that the current mode has been switched to the text mode (S806).

After confirming the input of the ACK tone from the other vehicle terminal 750, the C2CVM modem 602 switches to the text mode and notifies the service module 612. (S809) The vehicle terminal 650 and the other vehicle terminal ( After all of the 750 switches to text mode, service data 611 and 711 are transmitted and received.

While confirming the end of data transmission and reception (S810), if the data transmission and reception is not terminated, the data transmission and reception state is maintained continuously (S811). After the ACK data is detected, the apparatus waits for the detection of the ACK data (S812). In the case of receiving the end data of all the texts, the ACK data is transmitted to the voice mode, and the end of the text is the other vehicle terminal unit 750. Reconnects the call switch 706 so that the other vehicle user 701 can make a voice call. (S813) The unit receiving the ACK switches to the voice mode and receives the ACK from another vehicle terminal unit 750. In case of), the call switch 706 is connected again to allow the other vehicle user 701 to make a voice call.

FIG. 6 is a block diagram illustrating a C2CVM module shown in FIG. 4.

As shown, each of the C2CVM modems 602 and 702 included in the vehicle terminal 650 or the other vehicle terminal 750 is largely composed of a transmitter 401 and a receiver 413. Specifically, the transmission unit 401 (ie, encoding unit) of the C2CVM modem includes a service data input unit 402, an error correction inserter 403, a packet formatter 404, a signal modulator 405, and a PCM data output unit ( 406, the receiving unit 420 (i.e., the decoding unit) includes a PCM data input unit 427, a predictive model detector 428, a synchronization processor 429, a demodulator 423, an error correction eliminator 424, The service data output unit 422 is configured.

 In the transmission unit 401 of the C2CVM modem, the service data input unit 402 is an element that exchanges service data (611,711) with the upper application of the modem, and the error correction inserter 403 is a checksum, CRC (Cyclic Redundancy). Coded service data (611,711) is inserted by inserting error correction codes such as Check (FEC), Forward Error Crrection (FEC), and Low-Density Parity Check (LDPC), and packet formatter 404 is coded for error correction inserter. The data is composed of transmission data packets of a certain unit.

The signal modulator 405 modulates the binary signal produced by the packet formatter 404 into a form suitable for the vocoder algorithm for the wireless voice channel. The carriers of various frequency bands are arbitrarily used to modulate using DTMF, Multi array FSK, Multi array PSK, Multi Array DPSK, and Multi Array QPSK. For example, using low frequency band M-ary FSK, M-ary PSK, or M-ary BPSK, modulate digital data to have vowel frequency characteristics, and insert dummy signal of middle frequency band to make frequency characteristics of consonants. Can have The modulated signal is buffered by the PCM data output unit 406 and output to the upper application stage. In the receiver 820 of the C2CVM modem, the PCM data input unit 427 receives and buffers the PCM data from the upper application stage, and the predictive modem detector 428 is made by the signal modulator 405 of the transmitter 401. The signal is detected and transmitted to the synchronization processor 429 and the demodulator 423. The synchronization processor 429 synchronizes each step of the packet according to the detected signal. The demodulator 423 is an element that demodulates a modulated signal and extracts desired binary data. The error correction eliminator 424 is an element for generating user data by an error correction algorithm determined from the demodulated binary data. Finally, the decoded and extracted data is output by the service data output unit 422 to the upper application end.

FIG. 7 is a block diagram illustrating an output of the packet formatter 404 shown in FIG. 5.

As shown, the packet is composed of a header, a body, and a tail. The head consists of the start synchronous to inform the start of the packet, the type synchronous to inform the type of the packet, the flow control to be processed when an error occurs, and the start delimiter to distinguish the start of the body. The final tail consists of an end delimiter indicating the end of the body and a null to distinguish it from other packets.

As described above, in a digital data communication system for transmitting voice signals or digital data between vehicles, each vehicle includes a terminal that includes a C2CVM modem for modulating the digital data to include vowels of voice and frequency characteristics of consonants. Transmitting and receiving module for transmitting and receiving the output of the unit and the terminal through the voice channel of the mobile communication network is included. Through this, the data can be transferred in the vehicle through Bluetooth, and the data can be transferred between the vehicles using a mobile communication network.

Preferred embodiments of the present invention described above are intended for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, substitutions and additions through the spirit and scope of the appended claims, and such modifications may be made by the following patents. It should be regarded as belonging to the claims.

1 is a block diagram illustrating a short range communication system in a general inter-vehicle communication system.

2 is a block diagram illustrating a telecommunication system in a general inter-vehicle communication system.

3 is a block diagram illustrating an inter-vehicle communication system according to an embodiment of the present invention.

FIG. 4 is a block diagram illustrating in detail the inter-vehicle communication system illustrated in FIG. 3.

FIG. 5 is a flowchart of a mode switching scenario in the inter-vehicle communication system illustrated in FIG. 3.

FIG. 6 is a block diagram illustrating a C2CVM module shown in FIG. 4.

FIG. 7 is a block diagram illustrating an output of the packet formatter shown in FIG. 5.

Claims (5)

In a digital data communication system for transmitting voice signals or digital data between vehicles, each vehicle includes: A terminal unit including a C2CVM modem for modulating the digital data to include voice vowels and frequency characteristics of consonants; And Transceiver module for receiving the output of the terminal via Bluetooth to transmit and receive through the voice channel of the mobile communication network Digital data communication system comprising a. The method of claim 1, The terminal unit A service module for storing the digital data and for transmitting it to the C2CVM modem; A voice codec for converting an input voice signal into a digital signal or converting the digital signal into the voice signal; And And a Bluetooth module selectively connected to the service module and the voice codec and for transmitting and receiving the digital data with the transceiving module. The method of claim 1, The frequency characteristic of the vowel is a result of modulating the digital data using M-ary FSK, M-ary PSK, or M-ary BPSK of a low frequency band, and the frequency characteristic of the consonant is a dummy signal of a middle frequency band. Digital data communication system, characterized in that formed through. The method of claim 1, The transmission and reception module A Bluetooth module connected to the terminal to exchange the digital data; A vocoder for converting the Bluetooth module to be suitable for the voice channel; And And a mobile communication modem for modulating an output of the vocoder corresponding to the mobile communication network or for demodulating a signal transmitted through the mobile communication network. The method of claim 1, The mobile communication network is one of CDMA, GSM, WCDWA, Wibro, digital data communication system.

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