KR200281805Y1 - A real time display panel for a bus using DARC module - Google Patents

Abstract

The present invention relates to a real-time display board for traffic information using the DARC receiver.

The real-time display board according to the present invention includes a DARC transmitter, a DARC receiver, and a display board. In order to display information on the display board, the DARC transmitter includes traffic information, DGPS (Differential Global Positioning System), and geographic information system. (GIS) information, news, weather, securities information, and other FM additional information including the real-time addition and transmission, the DARC receiver receives the real-time FM additional information to separate the information, the separated additional information and stored information When displaying any one of the additional information and displaying the additional information, the user may select any one of the various pieces of display information so that the user can select any one of them. In addition, the stored information may allow the user to insert a desired advertisement or store other information for an area where additional information is not received. Such a real-time signboard is easy to receive anywhere, different information is displayed according to the selection of the necessary function of the signboard, it is possible to express the differentiated contents, and also because the supply of information is made in real-time broadcasting Maintain the speed and reliability of information.

Description

Real time display panel for traffic information using dark receiver {A real time display panel for a bus using DARC module}

The present invention relates to a real-time display board using a data radio channel (hereinafter referred to as "DARC") receiving unit, and more specifically, a real-time display board for transmitting and receiving the FM unit using the DARC module to display the information. It is about.

In general, electronic signboards are used to deliver information and advertising to unspecified people. Such display devices for information delivery and advertisement display various information through separate networks, but in the domestic reality where the information providing base is relatively weak compared to other countries, it is difficult to obtain the latest information from a reliable information provider quickly. There is this. In particular, in the case of a mobile display system installed on public transportation such as a railroad or a bus, information input methods are limited from the outside, and recently, attempts to receive information through public wireless networks have been made. There is a high cost of maintaining and operating a system for obtaining information.

In order to solve this problem, an FM additional broadcasting system has been introduced, which allows multiple users to multiplex and transmit various additional information to a broadcast radio signal to use a certain additional information at a lower cost and in an easier way.

The FM additional broadcasting system is a broadcasting system for providing a variety of information in addition to radio broadcasting by allowing a listener to add and transmit a radio data system signal or a DARC signal to a radio broadcasting signal. This DARC refers to a supplementary service for maximizing frequency operation efficiency by multiplexing additional digital information with existing FM broadcast waves. It is understood as a concept parallel to data broadcasting in TV broadcasting, and DARC broadcasting system is LMSK (Level controlled Minimum Shift Keying). It is a high-speed FM multi-broadcasting system called a new modulation system that can transmit about 2,000 English characters per second (1,000 Korean characters) at an information transmission rate of 16 Kbps per second.

DARC uses various textual data services such as real-time city and highway traffic information for vehicle navigation, differential global positioning system (DGPS), geographic information system (GIS) information, news, weather and securities information in the frequency band of 87.5 to 108 MHz. It is being spotlighted as a means of overcoming the limitation of information transmission by listening by providing through a graphic format.

DARC is 10 times faster than RDS method used in Europe and it is designed to correct error by multi-pass fading using error correction code (ECC). A new FM supplementary broadcast service to replace, and it offers a wide range of service areas, low operating costs and a complete network that does not require additional frequency spectrum, providing information to users who need real-time information. Plays an important role.

The additional broadcasting service using the DARC is usually transmitted from a broadcasting station by attaching a DARC decoder to an FM broadcast receiving device (such as a liquid crystal display device or an LED display board) equipped with a DARC decoder. After decrypting the data (after restoring it to the original data), the decrypted data is displayed on the display device, thereby making it possible to use visible information.

Accordingly, the present invention provides a device capable of displaying fast and reliable information on traffic information that is changed in real time by providing such an additional broadcasting receiver to a transportation means using various advantages of DARC. .

It is another object of the present invention to provide an apparatus capable of making a voice announcement for a stop by using such an additional broadcasting receiver.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a waveform diagram of the frequency spectrum of the baseband of an FM added broadcast signal.

2 is a block diagram of a conventional FM additional broadcast transmission and reception system.

FIG. 3 is a configuration diagram illustrating an example of the FM additional broadcast signal generation unit of FIG. 2.

4 is a block diagram of a real-time display board using a DARC receiver for traffic broadcasting according to the present invention.

5 is a view for explaining the structure of a frame according to the transmission protocol of the FM additional broadcast method for transmitting traffic information according to an embodiment of the present invention.

6 is a view illustrating a traffic information transmission protocol of a post system according to an embodiment of the present invention.

7 is a view illustrating a transmission protocol of each post according to an embodiment of the present invention.

8 is a flowchart illustrating a traffic information transmission method using a real-time sign board using a DARC receiver for traffic broadcasting according to an embodiment of the present invention.

9 is an exemplary view showing the traffic information on the display device according to an embodiment of the present invention.

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

100: DARC transmitter 110: DARC transmitter

120: FM additional broadcasting signal generator 130: FM additional broadcasting input unit

200: DARC receiver 210: DARC decoder

220: system control unit 230: information input unit

240: control signal input unit 250: storage unit

260: FM radio receiver 300: display device

400: traffic information collection server 410: traffic information integrated server

500: Post ID sending unit 510: Post ID input device

520: Post ID 600: Audio Device

900: display device

The real-time sign board using the DARC receiver for transportation means of the present invention for achieving this object is

A traffic information collection server unit 400 for collecting at least one traffic information in real time;

A traffic information integration server 410 which receives the collected traffic information through the Internet or a dedicated line and collects the integrated traffic information into an FM DARC transmission protocol;

A DARC transmitter 100 for receiving the integrated processed traffic information and giving a real-time FM radio broadcast signal to the FM additional traffic broadcast signal; And

A traffic post transmitter 500 for transmitting a traffic post ID; Wow

FM radio receiver 260; and

A DARC decoder 210 for separating and converting the traffic information and the post ID from the RF transmission signal and the traffic post transmitter; and

An information input unit 230 capable of editing and inputting information including the traffic information, post ID, and advertisement information; And

A control signal input unit 240 for controlling the DARC receiver to select information to be displayed; and

A storage unit 250 capable of storing the ad text, post name and other data; and

A system controller 220 which receives a signal from the information input unit and a control signal input unit and controls the entire system of the DARC receiver; and

A display device 300 for displaying the traffic information; and

And an audio device 600 for outputting voice information and post-names of the storage unit 250 as voice in the traffic information.

In addition, the traffic information using method of the real-time sign board using the DARC receiver for transportation means for realizing the above object,

Collecting traffic information for collecting at least one traffic information in real time;

Integrating the traffic information collected by receiving the collected traffic information through the Internet or a dedicated line and integrated into the FM DARC transmission protocol;

Multiplexing the converted DARC traffic information and broadcast audio signal by FM modulation and wirelessly transmitting the FM signal;

FM-modulating the corresponding post ID and transmitting the radio signal;

Receiving DARC traffic information and broadcasting audio signal from an FM broadcasting station;

Receiving an ID for each post;

Reading the traffic information and the post ID by separating the DARC traffic information, the post ID, and the audio signal by the DARC decoder;

And collecting information to be displayed, including the read traffic information, post ID, and self-stored information, and outputting the displayed or voiced information.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, in order to explain the present invention, a configuration of a conventional general FM additional broadcasting system will be described. 1 is a diagram illustrating a signal waveform diagram of a conventional conventional FM additional broadcasting system. In addition to the audio signals L + R and LR and pilot signals used for conventional broadcasting in the FM baseband waveform, FM additional broadcasting is performed. RDS signal and DARC signal are indicated to apply to the information transmission of the system.

Here, the RDS signal is a modulated data signal of 1,187.5bps using DBPSK method. The subcarrier frequency is 57 kHz, and the subcarrier level is 1.3 to 10%. use.

In addition, the DARC signal modulates a 16Kbps digital signal according to the level of the difference (LR) signal between the L-channel audio signal and the R-channel audio signal, thereby modulating minimum shift keying (MSK) and a band pass filter (BPF). The subcarrier is 76 kHz, the level of the subcarrier is 4 to 10% according to the LR signal level, and (272, 190) short-circuit codes are used for error correction during data transmission and reception.

FIG. 2 is a block diagram of a conventional FM additional broadcasting system including a DARC transmitter 100, a DARC receiver 200, and a display device 300.

The DARC transmitter 100 includes an FM additional broadcast input unit 130, an FM additional broadcast signal generator 120, and a DARC transmitter 110. The DARC transmitter 100 includes additional information such as traffic information, DGPS ( FM additional information including differential global positioning system), geographic information system (GIS) information, news, weather, securities information, etc. is added in real time.

In order to enable a conventional general FM additional broadcasting system to obtain necessary data from data transmitted for another additional broadcasting service, the FM additional broadcasting transmitter 100 may assign a code of service identification to the transmitted data. If the code for identification is not assigned, the existing additional broadcast service can be used as it is in the fixed information display system. This will be described below in detail.

The above-described FM additional broadcast signal generation unit 120 will be described in more detail with reference to FIG. 3 based on the DARC protocol.

3 is a configuration diagram for explaining an example of the FM additional broadcast signal generation unit 120 of FIG. 2 described above.

As shown in FIG. 3, the FM additional broadcast signal generator 120 includes a stereo generator 1100, a four multiplier 1200, an LMSK generator 1300, and a summer 1400.

The stereo generator 1100 includes a matrix circuit 1110, a frequency doubler 1120, and a multiplier 1130, and receives an L channel audio signal, an R channel audio signal, and a pilot tone signal. The first and second audio signals L + R and LR and the first multiplication signal 1131 are output.

In more detail, the matrix circuit 1100 receives the audio signal of the L channel and the audio signal of the R channel, provides the first audio signal L + R to the summer 1400, and the second audio signal LR. Are provided to the multiplier 1130 and the LMSK generator 1300, respectively.

The frequency doubler 1120 receives the pilot tone signal from the outside and multiplies it and provides the multiplier 1130 to the multiplier 1130.

The multiplier 1130 multiplies the second audio signal L-R provided from the matrix circuit 1110 and the frequency doubled signal provided from the frequency doubler 1120 and provides the multiplier 1400 to the summer 1400.

The frequency quadruple 1200 receives the pilot tone signal from the outside and multiplies it by four to provide the quadrupled pilot signal 1201 to the LMSK generator 1300.

The LMSK generator 1300 uses a second audio signal provided from the stereo generator 1100 using a Level Controlled Mininum ShiftKeying method for data received from the FM additional broadcast input unit 130. LMSK signal 1301 is provided to summer 1400 using an MSK modulation scheme that limits the amplitude of LR).

The summer 1400 receives the first audio signal L + R and the multiplication signal 1131 from the stereo generator 1100, and receives the pilot signal and the LMSK signal 1301 from the LMSK generator 1300 from the outside, respectively. Received and added to the output to the DARC transmission unit 110.

The DARC transmitter 110 receives the FM additional broadcast signal from the FM additional broadcast signal generator 120 and modulates the FM additional broadcast signal and transmits the FM additional broadcast signal through an antenna.

The DARC receiver 200 includes an FM radio receiver 260, a DARC decoder 210, an information input unit 230, a control signal input unit 240, a system control unit 220 and a storage unit 250, and a DARC transmitter 100. ) And receives the additional FM signal of which the additional information is mixed with the general FM broadcast signal and processes it into a signal that can be displayed on the screen.

More specifically, the FM radio receiver 260 demodulates an FM broadcast signal input through a broadcast receiving antenna, the DARC receiver 210 separates additional information from the demodulated FM broadcast signal, and separates the separated additional information. It serves to provide to the system control unit 220. In addition, the information input unit 230 edits the input information itself by the operator of the system, such as advertisements and announcements to be displayed separately, and provides the edited self information to the system control unit 230.

There is a control signal input unit 240 for controlling the information to be displayed on the display device from the information provided from the information input unit 230 and the advertisement information to select the information to be displayed, the storage unit 250 stores the ad text and other data Doing. The system controller 220 selects at least one of additional information separated from the DARC decoder 210 and its own information edited from the information input unit 230, and provides the selected information to the display device 300, and displays the display device 300. Displays the corresponding information provided from the system controller 220.

That is, as described above, the conventional general FM additional broadcast system is added to the general FM radio broadcast signal and transmitted traffic information, DGPS (Differential Global Positioning System), geographic information system (GIS) information, news, weather, securities Information such as information may be received and displayed, or advertisements edited by the user or display information for regions where DARC is not received may be displayed.

Hereinafter, an embodiment of a real-time sign board using a DARC receiver for transportation will be described. However, the description of the parts similar to the functions and configurations of the real-time sign board using the DARC receiver of the present invention will be omitted.

In FIG. 4, the traffic information collection server 400 includes a plurality of individual traffic information collection servers which collect traffic information through various paths, and collects the traffic information in real time through the Internet or a dedicated line. 410).

The traffic information integration server 410 properly processes the transmitted traffic information to generate accurate traffic information for each section or node, and traffic information of one section or node may be transmitted from different traffic information collection servers. And can also be conveyed in different contents to express the same traffic congestion phenomenon, so the traffic information transmitted in different forms and contents is processed into the same format, and the FM DARC transmission which presents the processed traffic information in the present invention. After the integrated processing into the protocol, the FM unit of the DARC transmitter 100 is provided to the broadcast input unit 130, so that the FM additional broadcast for the vehicle is transmitted according to the same description as in FIG.

At this time, the structure of the transmitted frame will be described with reference to FIG.

As illustrated in FIG. 5, one frame of the FM additional broadcasting method for transmitting traffic information according to an embodiment of the present invention includes 190 information blocks composed of 288 bits and 82 parity blocks composed of 288 bits.

Each information block is composed of a 16-bit block identification code, a 176-bit data packet, a 14-bit CyclicRedundancy Check (CRC) code, and an 82-bit parity. The parity block consists of a 16-bit block identification code and 272 bits of parity.

In general, the data link layer serves as a data set for transmitting all data packets from the upper layer to the physical layer where the actual data transmission is performed. In this case, the information of the header added to the data packet is used for various information required for data transmission in the network. Create a CRC to record the information so that it can be used as a reference for the reception of data. The main function of the data link layer is to send the completed data packet from the upper layer to the physical, which is the final transport layer, without error. When there is no reception completion message at the receiving side Resend the data. In this way, error checking of data reception of the data link layer is performed by checking the CRC of the packet, and when there is an error of the CRC, the transmission side is requested to retransmit. By specifying the other computer to receive data from other functions of the data link layer, the correct transmission is executed.

In addition, the post ID sending unit 500 is composed of a post ID input device 510 and a post ID sending device 520, the post ID input device 510 designates and changes the unique number for each post is set. It is a device capable of transmitting the unique number to the post ID transmitter 520, the post ID transmitter 520 is FM modulation to the data that can be received by the DARC receiver 200, the unique number of the transmitted post RF radio transmission at regular intervals. Even more preferably, the transmission period can be adjusted in the post ID input device (510).

Hereinafter, the operation of the system using the FM additional broadcasting service in the means of transportation by providing a real-time signboard using the DARC receiver in the means of transportation according to an embodiment of the present invention.

8 is a flowchart illustrating a traffic information transmission method using a real-time sign board using a DARC receiver for traffic broadcasting according to an embodiment of the present invention.

As shown in FIG. 4 and FIG. 8, first, a plurality of traffic information which changes in real time from a plurality of traffic information individual collection servers 410, 420, ..., N are collected (step 100).

After receiving a plurality of traffic information collected through various routes through the Internet or a leased line, the same traffic information may be different depending on the point of view of collecting the information. Processing is made into information for DARC (step 200).

The converted DARC traffic information and broadcast audio signal are multiplexed and FM-modulated to be wirelessly transmitted (step 300). Meanwhile, as shown in FIGS. 4 and 8, the traffic individual post transmitter receives an ID for each post (step). 400, FM modulation and radio transmission are performed (step 500).

The DARC receiving unit receives DARC traffic information, broadcast audio signal, and corresponding post ID from the FM broadcasting station (step 600).

Subsequently, the DARC traffic information and post ID are read from the signal (step 700), and the DARC receiver 200 inputs a stop name for each post through the information input unit 230 and stores the post name in the storage unit 250. In operation 910, the read information and the stop information stored in the storage unit are collected and displayed on the display device as shown in the exemplary embodiment of FIG. 9, or the information is voiced through the audio device.

6 is a diagram illustrating a traffic information transmission protocol of a post system according to an embodiment of the present invention.

As shown in FIG. 6, the traffic information transmission system of the post system has a 2-byte prefix (Byte 1, 2), a 1-byte status flag (Byte 3), and 4-byte starting point post ID information ( Byte 4 ~ 7), 4 bytes of destination post ID information (Byte 8 ~ 11), 1 byte of region ID information (Byte 12,13), 1 byte of current weather information (Byte 14), 1 byte of current temperature information (Byte 15), 1 byte of precipitation information (Byte 16), 1 byte of today's forecast information (Byte 17), 2 bytes of today's forecast temperature information (Byte 18, 19), 1 byte of today's precipitation probability information (Byte 20) ) And two bytes of CRC information (Byte 21, 22). In this case, the DARC Layer 4 CRC (CRC 16) is used for the 21st and 22nd bytes as the CRC information.

Specifically, the first byte (Byte 1) of the two-byte prefix includes two bits of update flags (B7 and B6), one bit of information termination information (B5), one bit of decoding identification information (B4), and four bits. Service identification information (B0 to B3), and the second byte (Byte 2) consists of a 4-bit data packet number (B4 to B7) and a 4-bit data group number (B0 to B3).

More specifically, the update flag has a sequential value in order of '00' → '01' → '10' → '11' → '00' → ‥‥ when the information is updated, and the information ending information is traffic information. Since it is a case of the link ID scheme represented in 1 packet, it always has a value of 1, the decoding identification information is 0, and the service identification code of the service identification information is 7 (B3: 0, B2: 1, B1: 1, B0). : Assign 1).

1-bit ID system B7, 1-bit direction information B6, 3-bit reserved area B5 to 3, 1-bit emergency information B2 of the third byte of the data block. It consists of additional information B1 of bits and character information B0 of one bit.

More specifically, the character information B0 is a format used when text needs to be delivered in the corresponding section. This bit indicates whether there is text related to the corresponding section in the traffic information area among the text service area (service identification: 2), and this bit and the text service can be used when the text related to the corresponding section is required. In this case, when the character information is '0', there is no corresponding text, and when the character information is 1, it indicates that there is text related to the node.

In addition, the additional information (B1) is a format for preparing a case of several kinds of accidents in one section, and determines whether the current traffic information is the only new traffic information or information to be added to the current traffic information. In this case, if the additional information is '0', the traffic information of the broadcasting packet is updated with the latest traffic information. If the additional information is '1', the traffic information of the broadcasting packet is updated. Information to be added to the traffic information, which is added to the traffic information of the node.

In addition, the emergency information (B2) determines whether the traffic information of the packet being broadcast is emergency information or general information. If the emergency information is '0', the general information is used, and when the emergency information is '1', Indicates emergency information.

The direction information B6 indicates traffic information in the forward direction and the reverse direction, and is set to '1' when the forward direction and the reverse direction are the same, and to '0' when the direction information is the same.

In addition, the fourth to seventh bytes of the data block is a format for designating a starting point post ID, and the starting point post ID is for assigning and managing a post-specific ID of a stop post ID indicating a starting point of a region to which the transportation means passes. It can be added or subtracted in size depending on the number of posts. The eighth to eleventh bytes of the data block are in a format for designating an end post ID, and the end post ID is for assigning and managing a post-specific ID number of a stop post ID indicating a destination of an area to which the transportation means passes. Depending on the number of posts, the size can be added or subtracted. In addition, the twelfth to thirteenth bytes of the data block may be managed by specifying a unique number for each region, such as Gangwon, etc., and indicate an area to which subsequent information belongs. The 14th byte designates a unique number for each current weather such as sunny, cloudy, etc., the 15th byte is the current temperature, the 16th byte is the precipitation, the 17th byte is cloudy and sometimes rainy information, For today's forecasts, the 18th to 19th bytes specify the corresponding data so that the morning temperature is the 18th byte, the 19th byte is the afternoon temperature, and the 20th byte is the today's precipitation probability. will be.

7 is a diagram illustrating a transmission protocol of each post according to an embodiment of the present invention.

As shown in FIG. 7, each post ID transmitter 500 preferably uses the same format as the traffic information transmission protocol of the post system of FIG. 6 in order to increase transmission efficiency. Therefore, the two-byte prefix (Byte 1, 2) and the one-byte status flag (Byte 3) have the same function and information, and four-byte post ID information (Bytes 4 to 7) and eighth to twentieth bytes. The information up to is processed to be reserved in the reserved area. Post ID information of 4 bytes (Byte 4 to 7) is transmitted by inputting a post number uniquely designated for each post.

As described above, necessary information can be designated and used for each byte, and a reserved area can be reserved in case of need in the future.

While the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

As described above, according to the present invention, by collecting various traffic information that is changed in real time and FM-modulated together with the audio signal for broadcasting and transmitting radio signals, the traffic information that changes at any time for a desired section at a desired time to the information user wanting real-time traffic information. It can be provided, and it is also effective to solve problems caused by hearing or visually impaired people who cannot see or hear, and also provides weather information in real time by combining weather information of the desired time and desired area with post information. By doing so, there is an advantage of providing comprehensive information combining traffic and weather as well as fragmentary traffic information.

In addition, the user can insert the desired advertisement or store other information for the region where the additional information is not received while providing the information, thereby increasing its efficiency and promoting the advertising effect through the advertisement. ..

In this way, the real-time display board using the DARC receiving unit can be easily received anywhere, so that different information can be displayed according to the selection of the necessary functions of the display board. This ensures the speed and reliability of the information presented.

Claims (8)

In the display device for transportation means using FM additional broadcasting, A DARC transmitter 100 which receives the integrated processed traffic information and gives a real time to a general FM radio broadcast signal and transmits the RF as an FM additional traffic broadcast signal; And A traffic post transmitter 500 for transmitting a traffic post ID; Wow FM radio receiver 260; and A DARC decoder 210 for separating and converting the traffic information and the post ID from the RF transmission signal and the traffic post transmitter; and An information input unit 230 capable of editing and inputting information including the traffic information, post ID, and advertisement information; And A control signal input unit 240 for controlling the DARC receiving unit to select information to be displayed; and a storage unit 250 capable of storing the ad text, the name and other data for each post; and a signal from the information input unit and the control signal input unit. Receiving the system control unit 220 for controlling the entire system of the DARC receiver; And Display device 300 for displaying the traffic information; Real-time display board for traffic information using a DARC receiving unit, characterized in that consisting of According to claim 1, Traffic information using the DARC receiver further comprises; audio device 600 for outputting the voice information and the name of each post of the storage unit 250 as a voice of the traffic information; Realtime scoreboard. According to claim 1, The traffic information collection server 400 for collecting at least one or more traffic information in real time and the collected traffic information received through the Internet or a dedicated line to collect and integrated into the FM DARC transmission protocol The real-time electronic board for traffic information using the DARC receiver further comprises a traffic information integration server 410 for transmitting to the DARC transmitter 100 2. The memory device of claim 1, wherein the storage unit 250 first stores user text or image files, and then stores FM additional broadcasting information such as news, time, weather, and stock information, and then stores a bus stop voice file. Real-time electronic scoreboard for traffic information using the DARC receiver, which stores sequentially and the contents of the next output option, and finally the information of the bus stop [5] The real-time scoreboard for traffic information according to claim 4, wherein the user text or image file of the memory card block further includes an advertisement image by a user. 5. The DARC receiving unit according to claim 4, wherein the information file of the bus stop of the storage unit 250 stores files that record the names of the stops and the stop post IDs of the order of the stops and the total number of stops. Real time display board for traffic information. According to claim 1, wherein the traffic post transmitter 500 is a real-time electronic board for traffic information using a DARC receiver, characterized in that consisting of a post ID input unit (510) and a post ID transmitter (520). The data transmission configuration of the post ID transmitter 520 is a 2-byte prefix (Byte 1, 2), a 1-byte status flag (Byte 3), a 4-byte starting point post to increase the transmission efficiency. ID information (Byte 4 ~ 7), 4 bytes of destination post ID information (Byte 8 ~ 11), 1 byte of local ID information (Byte 12,13), 1 byte of current weather information (Byte 14), 1 byte of Current temperature information (Byte 15), 1 byte of precipitation information (Byte 16), 1 byte of today's forecast information (Byte 17), 2 bytes of today's forecast temperature information (Byte 18, 19), 1 byte of today's precipitation probability information (Byte 20) and two-byte CRC information (Byte 21, 22) real-time electronic board for traffic information using a DARC receiver.