JP5486247B2 - Train radio apparatus and train operation system using the same - Google Patents

Description

  The present invention relates to a train radio device and a train operation system using the train radio device, and in particular, a train radio device suitable for use in a monitoring system for displaying a home monitoring video to a crew member in a train, and the same. It relates to the train operation system used.

  In recent traffic systems, it has become common to take pictures of vehicles and passengers with a surveillance camera for crime prevention and safety. Non-Patent Document 1 describes the use and usage of such a surveillance camera.

  As one example where such a surveillance camera is used, in a train operation system, a technology is known in which the situation of the platform is imaged by the surveillance camera, and the image is transmitted to the crew in the train to confirm safety. It has been. Patent Document 1 discloses a platform monitoring system in which a surveillance camera is installed on a platform, and in particular, a transmission distance is shortened and a captured image is transmitted to a train. Patent Document 2 discloses a safety confirmation system in which an open / closed state of a door is detected, an image of the vicinity of the door is captured by a monitoring camera, and personnel confirm it.

JP 2002-264811 A JP-A-9-71240

Free encyclopedia "Wikipedia", "surveillance camera", [online], [search August 3, 2009], Internet <URL: http: //en.wikipedia.org/wiki/%E7%9B % A3% E8% A6% 96% E3% 82% AB% E3% 83% A1% E3% 83% A9>

  The prior art described above is intended for safety of operation by the crew member grasping the situation of the platform and the situation near the door of the train. However, the above prior art does not consider the train speed and the necessity of images. The platform image captured by the surveillance camera is meaningful when the train stops or the speed is extremely slow, but when the train speed is a certain level, the surveillance image is based on the platform image captured by the surveillance camera. Monitoring by is no longer performed, resulting in uselessness. For this reason, in the prior art, wasteful monitor display is performed and power is excessively consumed.

  The present invention has been made to solve the above problems, and in the monitoring of a train operation system, a train radio that controls display of a monitoring image according to the speed of the train and enables power saving. To provide an apparatus.

  The train radio apparatus of the present invention is a train radio apparatus that is connected to an imaging apparatus and transmits a captured image captured by the imaging apparatus to a radio apparatus installed in the train, and is a Doppler frequency of a reflected wave of a transmission radio wave The train speed is obtained on the basis of the information, and the train speed obtained in the communication frame is set and transmitted together with the image connected by the imaging device.

  In the train operation system of the present invention, an imaging device, an image compression device, and a train radio device are connected as devices outside the train, and an image captured by the imaging device is compressed by the image compression device. Transmit from the train radio device outside the train.

  The train radio apparatus outside the train measures the speed of the train from the Doppler frequency of the reflected wave of the transmission radio wave, sets it as a communication frame, and transmits it together with the compressed image data.

  On the other hand, a train radio device, a speed determination control device, an image expansion device, and a display device are connected as devices in the train. The train radio device in the train extracts speed information from the communication frame of the train radio device outside the train, sends it to the speed judgment control device, and sends the image data to the image decompression device. When it is determined that the speed is equal to or greater than a certain value, the speed determination control device performs control so that the image expanded by the image expansion device is not sent to the display device.

  ADVANTAGE OF THE INVENTION According to this invention, in the monitoring of a train operation system, the display of a monitoring image is controlled according to the speed of a train, and the train radio | wireless apparatus system which enables power saving can be provided.

It is a system configuration figure of a train operation system concerning one embodiment of the present invention. It is an image figure of the train operation system which concerns on one Embodiment of this invention. It is the figure which showed the structure of the communication frame. 1 is a block diagram showing a configuration of a train radio apparatus (outside of a train) 201. FIG. It is a block diagram which shows the structure of the train radio apparatus (inside a train) 202.

  Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 to 5.

First, the system configuration and operation of a train operation system according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a system configuration diagram of a train operation system according to an embodiment of the present invention.
FIG. 2 is an image diagram of a train operation system according to an embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of a communication frame.

  A train operation system according to an embodiment of the present invention is a system that wirelessly transfers a home monitoring image to a train. The crew member 10 (driver, conductor) in the train can thereby make the operation safe.

  As shown in FIG. 1, the train operation system according to an embodiment of the present invention includes an imaging device (camera) 207, an image compression device 210, and a train radio device (outside of a train) 201 on the platform side. On the side, a display device 213, an image expansion device 212, a speed determination control device 211, and a train radio device (inside the train) 202 are installed.

  FIG. 2 shows an image of the system that is actually installed and operated on a station platform and a train.

An imaging device (camera) 207 is attached to a support column 208 in the home, and is connected to the image compression device 210 by a cable 209. The image compression apparatus 210 and the train radio apparatus (outside the train) 201 are also connected by a cable 209. A train radio device (inside the train) 202 is attached to the train 203, and although not shown in FIG. 2, a display device 213, an image expansion device 212, and a speed determination control device 211 are installed inside the train, Wired connection. The train radio apparatus (outside of the train) 201 and the train radio apparatus (inside the train) 202 communicate with each other wirelessly , the train radio apparatus (outside of the train) 201 is connected to the train radio apparatus (inside the train) 202, and the train 203 is the rail 204. The speed when moving up is measured, and the speed information and the monitoring image captured by the imaging device (camera) 207 are wirelessly transmitted to the train 203. The radio frequency band is preferably a millimeter wave band with little scattering and excellent straightness, for example, a 60 GHz band.

  The imaging device (camera) 207 transmits a monitoring image connected in the home as an analog signal to the image compression device 210 via the network. The image compression apparatus 210 converts the image data into a predetermined image format, for example, a JPEG (Joint Photographic Experts Group) image, and sends the image data to the train radio apparatus (outside the train) 201.

  At the same time, the train radio apparatus (outside of the train) 201 transmits a radio wave to the train 203 and measures the Doppler frequency returned from the train 203, thereby calculating the train speed and monitoring the train radio apparatus (outside of the train) 201. Along with the image, the information is transmitted in a communication frame (detailed structure will be described later).

  The train radio apparatus (inside the train) 202 receives the communication frame, separates the speed information, inputs it to the speed determination control apparatus 211, and inputs image data such as JPEG format to the image expansion apparatus 212.

  The speed determination control device 211 sends a signal to the image expansion device 212, and stops transmission (output) of the signal from the image expansion device 212 to the display device 213 when the speed is a certain speed (for example, 5 km / h). When the speed is lower than a certain speed, a signal is transmitted (output) to the display device 213 and a monitoring image is displayed. At this time, the image expansion device 212 converts image data such as JPEG format into an analog signal, and the display device 213 displays an image based on the analog signal.

Here, the frequency transmitted from the train radio apparatus (outside the train) 201 to the train radio apparatus (inside the train) 202 is f ₁ , the frequency transmitted from the train radio apparatus (inside the train) 202 to the train radio apparatus (outside the train) 201. When f ₂ and the Doppler frequency of the reflected wave are f _d , the frequency of the reflected wave measured by the train radio apparatus (outside the train) 201 is f ₁ ± f _d . Here, when the train approaches, the sign is set to +, and when the train moves away, the sign is set to-. The Doppler frequency _fd is given by the following (Equation 1).
f _d = v · (f ₁ / c) (Formula 1)
Here, f _d : Doppler frequency [Hz], f ₁ : transmission frequency [Hz], v: speed of moving body (train), [m / s], c: speed of light [m / s].

Whether the frequency of the radio wave measured by the train radio apparatus (outside of the train) 201 is due to reflected waves or the radio wave transmitted from the train radio apparatus (inside of the train) 202 to the train radio apparatus (outside of the train) 201 is f. _1, it can be easily determined if made to have a difference in degree of width f _2.

  The communication frame 300 between the train radio apparatus (outside the train) 201 and the train radio apparatus (inside the train) 202 has, for example, the format shown in FIG.

  As shown in FIG. 3, the communication frame 300 includes a speed information signal area 301, a data signal area 302, and a speed measurement signal area 303.

  The speed information signal area 301 is an area for setting speed information measured by the train radio apparatus (outside the train) 201. The data signal area 302 is an area for setting image information data in JPEG format or the like. The speed measurement signal area 303 is data for measuring the Doppler frequency by the train radio apparatus (outside the train) 201. For example, constant data in which all bits are 1 in 2 bytes is set.

Next, the configuration and operation of the train radio apparatus will be described with reference to FIGS. 4 and 5.
FIG. 4 is a block diagram showing the configuration of the train radio apparatus (outside the train) 201.
FIG. 5 is a block diagram showing a configuration of the train radio apparatus (inside the train) 202.

  As shown in FIG. 4, the train radio apparatus (outside the train) 201 includes a transmission antenna 101, a transmission RF unit 103, a modulation unit 106, a frame generation unit 109, a speed measurement signal region generation unit 110, and a speed signal region generation unit. 114, an OSC unit 105, a reception antenna 102, a reception RF unit 104, a low-pass filter 107, an A / D conversion unit 111, a moving speed calculation unit 113, a band-pass filter 108, a demodulation unit 112, and a network I / F unit 116.

  Further, the train radio apparatus (inside the train) 202 does not include the moving speed calculation unit 113, the speed measurement signal area generation unit 110, and the speed signal area generation unit 114 in the train radio apparatus (outside the train) 201, and speed information. An external output unit 115 is added.

  In the train radio apparatus (outside the train) 201, the speed measurement signal area generation unit 110 and the speed signal area generation unit 114 generate respective data.

  In addition, image data in the JPEG format obtained by compressing the image of the monitoring camera 207 is sent from the image compression apparatus 210, so the frame generation unit 109 receives this via the network I / F unit 116.

The frame generation unit 109 receives these data and generates the communication frame 300 shown in FIG. Then, the modulation unit 106 generates a modulated signal, the transmission RF unit 103 converts the frequency of the signal to be transmitted into a millimeter wave signal, and the communication frame 300 is transmitted to the train side at the frequency f ₁ .

On the other hand, the train radio apparatus (outside the train) 201 receives a reflected wave of its own transmission radio wave from the reception antenna 102. The received reflected wave is multiplied with the signal of the OSC unit 105, and the reception RF unit 104 converts the millimeter wave signal into a signal having a low frequency component (baseband) near DC. The signal is band-limited (filtered) by the low-pass filter 107, input to the A / D converter 111, and converted into a digital signal. The moving speed calculation unit 113 calculates the moving speed of the train, which is a moving body, based on the Doppler frequency f _d obtained from the digital signal converted by the A / D conversion unit 111 and transmits it to the speed information signal area 114.

The train radio apparatus (inside the train) 202 receives the radio wave of the frequency f ₁ of the train radio apparatus (outside the train) 201 from the reception antenna 102. The received signal is multiplied with the signal of the OSC unit 105, and the reception RF unit 104 converts the millimeter wave signal into a signal having a low frequency component (baseband) near DC. The signal is band-limited (filtered) by the band-pass filter 112, input to the demodulation unit 112, and transmitted to the image expansion device 212 via the network I / F unit 116 as an analog signal.

  On the other hand, a signal converted from a millimeter wave signal into a signal having a low frequency component in the vicinity of DC is band-limited (filtered) by the low-pass filter 107 and input to the A / D conversion unit 111 to be a digital signal. Is converted to The speed information external output unit 115 extracts the speed information in the speed information signal area 301 from the digital signal converted by the A / D conversion unit 111 and transmits it to the speed determination control device 211 via the network I / F unit 116. .

  In the description of the above embodiment, the train radio apparatus (outside of the train) 201 always transmits the communication frame to the train radio apparatus (inside the train) 202 regardless of the moving speed of the train. 211 determines whether or not to display a monitoring image on the display device 213. However, a means for determining the speed is provided in the train wireless device (outside of the train) 201, and the train speed becomes a certain level or more. The transmission of the communication frame may be stopped. By doing so, wasteful communication does not occur between the train radio device (outside of the train) 201 and the train radio device (inside the train) 202, and various devices in the train do not operate, which contributes to further power saving. it can.

DESCRIPTION OF SYMBOLS 101 ... Transmission antenna, 102 ... Reception antenna, 103 ... Transmission RF part, 104 ... Reception RF part, 105 ... 0SC part, 106 ... Modulation part, 107 ... Low pass filter, 108 ... Band pass filter, 109 ... Frame generation part, 110 ... speed measurement signal region generation unit, 111 ... A / D conversion unit, 112 ... demodulation unit, 113 ... movement speed calculation unit, 114 ... speed information signal region generation unit, 115 ... speed information external output unit, 116 ... network 1 / F part.
201: Train radio device (outside train), 202 ... Train radio device (inside train), 203 ... Train Train, 204 ... Track, 205 ... Post, 206 ... Home, 208 ... Post, 209 ... Cable, 210 ... Image compression device , 211... Speed determination control device, 212... Image expansion device, 213.

Claims (2)

An imaging device;
An image compression device that is connected to the imaging device and compresses a captured image of the imaging device;
Train radio device outside the train that is connected to the image compression device and transmits image data of a captured image compressed by the image compression device;
A radio device in the train that receives the image data of the captured image from the train radio device outside the train, and
An image expansion device connected to a radio device in the train, receiving image data of a captured image from the radio device in the train, and decompressing the compressed image data;
A train operation system including a display device connected to the image expansion device and displaying a captured image of the expanded image data,
The train radio apparatus outside the train obtains the train speed based on the frequency of the reflected wave of the transmission radio wave, and when the speed is equal to or greater than a certain value, the image data of the captured image to the train radio apparatus in the train Train operation system characterized by stopping transmission of trains. An imaging device;
An image compression device that is connected to the imaging device and compresses a captured image of the imaging device;
Train radio device outside the train that is connected to the image compression device and transmits image data of a captured image compressed by the image compression device;
A radio device in the train that receives the image data of the captured image from the train radio device outside the train, and
An image expansion device connected to a radio device in the train, receiving image data of a captured image from the radio device in the train, and decompressing the compressed image data;
A train radio apparatus outside the train in a train operation system, comprising a display device connected to the image expansion device and displaying a captured image of the expanded image data,
A train radio characterized by obtaining a train speed based on a reflected wave of a transmission radio wave, and stopping transmission of image data of the captured image to a train radio device in the train when the speed is equal to or greater than a certain value. apparatus.

Images