KR20050015425A - Wireless terminal device for wirelessly receiving and recording an image for a railway crossing, concerned with preventing an automobile from crashing into a train - Google Patents

Abstract

PURPOSE: A wireless apparatus for receiving and recording an image for a railway crossing is provided to secure safety in rail management by alarming a driver when the driver approaches a railway crossing. CONSTITUTION: A wireless apparatus for receiving and recording images of railroad crossroads includes a GPS receiver(20) or a beacon receiver(12), a frequency mapping table(13), a demodulator(14,15), a signal level detector(19), a channel select tuner(18), an image decoder(16), a monitor(17), and a digital image recorder. The GPS receiver or the beacon receiver calculates a current position of a train. The frequency mapping table stores a list of received frequencies related to image transmitters. The demodulator demodulates an antenna signal and a data signal. The signal level detector detects existence of the image and data signals. The digital image recorder records the image received from the image decoder.

Description

Radio image reception and recording terminal equipment at railroad crossings and dangerous areas

The present invention relates to a railroad safety wireless video receiving and recording device for preventing a safety accident during driving of a train, and receives a video signal transmitted from a wireless video transmitting device including a surveillance camera fixedly installed in a dangerous area around a railway track. In order to record, the present invention relates to a railroad safety wireless video receiving and recording device comprising a GPS 20 receiving unit and a wireless video receiving unit installed in a running train, and an image display and recording unit.

After installing the video camera at the railroad crossing or the dangerous area around the track, the driver can see the 2Km front image through the wireless video receiver in the driving train approaching within a certain distance. The purpose is to prevent it.

In general, up to now, railroad crossings have been alerted by alarm lights, alarm sounds, announcements, etc. to prevent safety accidents.

In the case of the conventional method as described above, there was no way of knowing the situation ahead in front of the driver of the train. In addition, since the brake operation distance is required about 2 km after anomaly in front of the constant speed driving, the visual detection of the driver of the engine room is not helpful for preventing accidents.

The present invention uses two methods as follows to solve the means for determining whether the crossing is installed in the crossing or the danger prediction area and the specific frequency selection means for freezing the wireless video transmitter. How to find the current position of the train by the first GPS (20), or find the wireless video transmitter near the train driving direction by receiving the source identifier by the beacon (12) to obtain the corresponding frequency associated with the source from the frequency mapping table to be. In the second method, the channel is tuned to a specific channel by sequentially changing channels through the channel selection and tuning unit of the receiver, and after detection, the channel selection and tuning unit 18 detects the presence or absence of a received image signal by the signal level detector 19. ) To feed back. When the effective reception frequency is detected by both the above methods, the first method by the GPS 20 or the beacon 12 is prioritized and the panel is selected. When the detected valid signal is lost for a predetermined time (3 to 10 seconds), the above process is repeated to detect the effective frequency.

In order to realize the above object, the present invention provides a wireless video transmitting device unit (FIG. 1) including a surveillance camera installed to view a situation of a railroad crossing and a dangerous roadside danger area, and a wireless video receiving device unit installed in a running train ( 2) are largely distinguished.

FIG. 1 is a block diagram schematically showing a wireless video transmitter, and FIG. 2 is a block diagram schematically showing a wireless video receiver.

In FIG. 1, video information input from the video camera 1 in the wireless video transmitting apparatus unit is mixed with caption information generated by the character generator 2. The resultant signal is digitally coded through a specific compression process in the image encoder (3), and general primary modulation (4) such as phase shift keying (PSK) and frequency shift keying (FSK) is performed. In order to widen the bandwidth of the primary modulated wave, the secondary modulation 5 is performed. After spreading modulation is performed in this manner, wireless transmission is performed through a transmission antenna 6 such as a horn antenna, a grid, or a parabola antenna.

The GPS 20 in the wireless video receiving apparatus of FIG. 2 calculates the current position of the train, searches for adjacent wireless video transmitters, and sets the frequency with the corresponding frequency registered in the frequency mapping table 13. In addition, even when an adjacent wireless video transmitter is not found in the frequency mapping table 13, when a valid video signal is detected by the data signal level detector 19, normal reception is started. In order to receive the data signal of the selected specific frequency, the secondary demodulation 14 or despreading is performed in order to receive the spread-modulated signal received at the reception antenna 11 intact. Since the despread signal is almost equivalent to the first spread signal at the transmitting side, the first demodulation (normal demodulation) 15 is performed. When the image is subjected to the encoding process in the wireless image transmitting apparatus, the image is output to the monitor 17 through the image decoder and the DVR 16.

When the operating train is crossing the road or approaching the estimated danger area, the driver can be alerted with an alarm and the monitor installed in the train can check the situation ahead so that proper response can be made in advance. In addition, the video is recorded through the digital recorder (DVR) so that the video can be searched if necessary.

1 is a block diagram schematically showing a wireless video transmission device;

2 is a block diagram schematically illustrating a wireless image receiving apparatus.

1: CCD camera 2: Character generator 3: Image encoder

4: primary modulator 5: secondary modulator 6: wireless antenna

7: beacon generator

11 wireless antenna 12 beacon receiver 13 frequency mapping table

14: secondary decoder 15: primary decoder 16: video decoder and DVR

17 monitor 18 channel select tuning unit 19 data signal level detector

20: GPS

Claims (5)

The GPS receiver 20 or the beacon receiver for calculating the current position of the train is a wireless image receiver and recording unit installed in the engine room to receive the image from the railroad crossing or the railway area dangerous predicted area (Fig. 1). (12), a frequency mapping table 13 in which a reception frequency list associated with the image transmitter is registered, an antenna 11 for data reception, demodulators 14 and 15 for demodulating data signals, and images and data. The signal level detector 19 for signal presence determination and the channel of a predetermined section are repeatedly rotated so that the channel selection tuning unit 18 for selecting a specific channel and the image decoder 16 for decoding the encoded video are displayed. Railroad safety wireless image receiving and recording device comprising a monitor (17) for display and a digital video recorder (DVR) for recording the received image. In the above-described claim 1, the GPS 20 is configured as a method for obtaining a current position of a running train. The beacon generator 7 and the beacon receiver 912 for transmitting and receiving an identifier (id) sent from the image transmitter in place of the GPS 20 as a method for obtaining a wireless image transmitter close to the train. It can be configured as. The video encoder (3) and the video decoder (16) according to claim 1, wherein the video encoder (3) and the video decoder (16), which are equipments for encoding or decoding the video for effective compression transmission and reception by the transmission / reception technology of the wireless video transmission unit and the wireless video reception unit. It is constructed using a codec. The apparatus of claim 1, wherein the apparatus encodes and decodes the images of the wireless video transmitter and wireless video receiver. It can be configured by replacing a network digital recorder (Network DVR) in place of the codec (Codec).