JP2016174235A - Data transmission system and load distribution device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve fast data transmission with a data transmission system including a plurality of transmission systems for wirelessly transmitting data.SOLUTION: A load distribution device 5 has a transmission buffer for holding a transmission waiting IP packet (an example of divided data) distributed to the transmission system for each transmission system using a transmission FPU 2 and a reception FPU 3. When vacancy becomes unavailable in a transmission buffer associated with either of transmission systems, the transmission system is excluded from a distribution destination of an IP packet until vacancy becomes available in the transmission buffer associated with the transmission system.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a data transmission system including a plurality of transmission systems that transmit data wirelessly.

  2. Description of the Related Art Conventionally, broadcasting materials including video and audio (hereinafter referred to as “materials”) are recorded and transmitted to broadcasting stations and the like at news gathering sites for broadcasting news reports and the like. For transmission of material, a method of transmitting the material itself in baseband using a basic function of an FPU (Field Pickup Unit) (see, for example, Patent Document 1), or a material filed as an IP through an IP (Internet Protocol) network. There is a transmission method (for example, see Patent Document 2).

JP 2002-359826 A JP 2001-119433 A

In the case of a system in which the recorded material is transmitted by the FPU, in a simple configuration, as shown in FIG. 4, the data of the material recorded by the camera 1 at the interview site is transmitted wirelessly from the transmission FPU 2 and the center side of the broadcasting station or the like. Is received by the receiving FPU 3 provided to the material receiving equipment 4.
In the conventional FPU transmission as described above, the high speed and low error rate characteristics of the FPU can be used for immediate material transmission. The same amount of time was required, and it was difficult to use depending on the length of the material. Although it can be assumed that FPUs are multiplexed, it is technically difficult to divide the baseband itself.

  On the other hand, in the case of a method in which the recorded material is converted into a file, converted into an IP packet, and transmitted by IP, a general IP transmission path can be used only at a speed of about 10 Mbps at most unless it is an optical cable as a dedicated line. . For this reason, images that require about 50 Mbps in the baseband, such as HD (High Definition) type images, can be relatively easily converted into a file and transmitted in IP packets, but about 5 times the recording length of the material. Therefore, it is difficult to handle the transmission of the material.

  In recent years, there is a device that converts a baseband signal into an IP packet and performs IP transmission, and then converts the IP packet into a baseband signal, and reversely connects the IP packet using the FPU transmission path. Some of them were transmitted, but as a result, it took the same time as baseband transmission.

In addition, as shown in FIG. 5, a load distribution device 7 provided on the data transmission side is provided with a plurality of transmission systems using the transmission FPU 2 and the reception FPU 3 (n systems of # 1 to #n in FIG. 5). There is also a mechanism in which material data is divided into a plurality of IP packets and distributed to each transmission FPU 2, and the reconstruction device 8 provided on the data receiving side restores the material data based on the IP packets received by each reception FPU 3. It was examined. This is expected to improve the apparent transmission speed by evenly distributing IP packets with a load balancer for IP transmission or the like.
However, since FPUs that use radio waves do not necessarily have the same transmission speed (link speed) due to differences in radio wave environment, when trying to evenly distribute IP packets to each FPU, the transmission speed is adjusted to the speed of the FPU that is slow to transmit. As a result, the combined performance of the transmission rates of the respective FPUs cannot be obtained.

  The present invention has been made in view of the above-described conventional circumstances, and provides a technique capable of speeding up data transmission for a data transmission system including a plurality of transmission systems that transmit data wirelessly. The purpose is to propose.

  In the present invention, a data transmission system includes a plurality of transmission systems that transmit data wirelessly and a load distribution device that distributes divided data obtained by dividing data to be transmitted to the plurality of transmission systems. Then, the load balancer has a buffer for holding the divided data waiting for transmission distributed to the transmission system for each transmission system, and when there is no space in the buffer of any transmission system, The transmission system is excluded from the distribution destination of the divided data until the buffer of the transmission system becomes empty.

  As a result, even if there is no free space in the buffer of any transmission system, the distribution of the divided data is delayed until the free space is generated in the buffer, so that the data transmission is not delayed. For this reason, data transmission by radio can be speeded up.

Here, as one configuration example, each of the plurality of transmission systems performs transmission of divided data using the FPU, and the load distribution apparatus distributes the divided data to the plurality of transmission systems. At a ratio corresponding to the FPU link speed.
Thereby, data transmission can be performed by effectively using the transmission capability of each transmission system.

  According to the present invention, even when there is no space in the buffer of any transmission system, the distribution of the divided data is delayed until the buffer is free, so that there is no situation in which data transmission is delayed. Can speed up data transmission.

It is a figure which shows the structural example of the data transmission system which concerns on one Embodiment of this invention. It is a figure which shows the example of the processing flow by the side of the data transmission by the data transmission system of FIG. It is a figure which shows the example of the processing flow by the side of data reception by the data transmission system of FIG. It is a figure which shows the structural example of the data transmission system which has 1 system FPU which concerns on a prior art example. It is a figure which shows the structural example of the data transmission system which has multiple systems FPU which concerns on a prior art example.

A data transmission system according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration example of a data transmission system according to an embodiment of the present invention.
Similar to the conventional example shown in FIG. 5, the data transmission system of this example includes a plurality of transmission systems (n systems of # 1 to #n in FIG. 1) using the transmission FPU 2 and the reception FPU 3, and transmits data. The load distribution device 5 provided on the side divides the data of the material recorded by the camera 1 into a plurality of IP packets (examples of divided data) and distributes them to each transmission FPU 2, and the reconstruction device 6 provided on the data reception side However, the material data is reconstructed (restored) based on the IP packet received by each reception FPU 3 and supplied to the material reception facility 4.

In the data transmission system of this example, a normal IP packet to baseband signal conversion mechanism and a baseband signal to IP packet conversion mechanism are used.
In the data transmission system of this example, a plurality of transmission systems are provided to make the wireless section multichannel. The radio channel can be multi-channeled by various methods, for example, polarization multiplexing, Los-MIMO (Line-Of-Sight Multiple-Input Multiple-Output), or the like.
Furthermore, in the data transmission system of this example, the following mechanism is provided in the load distribution device 5 and the reconstruction device 6 in order to realize high-speed data transmission by radio.

  The load balancer 5 has a plurality of IP packet transmission ports (output ports) to which the transmission FPU 2 can be connected, and a separate transmission buffer is provided for each IP packet transmission port. That is, the load distribution apparatus 5 includes a transmission buffer for holding a transmission-waiting IP packet distributed to each transmission system (a set of a corresponding transmission FPU2 and reception FPU3) for each of a plurality of transmission systems.

Further, when the load distribution device 5 divides the data (file) of the material to be transmitted into predetermined units and converts it into IP packets, the load distribution device 5 separates the IP protocol from order information (for example, the order of IP packets). A sequential number) is assigned to each IP packet as a system.
Then, the load balancer 5 cyclically outputs (distributes) the IP packets at a predetermined distribution ratio to the transmission buffer at each IP packet transmission / reception port to which the transmission FPU 2 is connected. To go. At this time, the availability of the sending buffer of the IP packet sending / outlet in the order of distribution is checked. If there is no available sending buffer, the IP packet is output to the sending buffer of the next IP packet sending / receiving port. .
By repeatedly performing the above processing, IP packets can be transmitted without interruption to the transmission FPU 2 of a plurality of transmission systems.

The reconstruction device 6 has a plurality of IP packet reception ports (input ports) to which the reception FPU 3 can be connected, and a common reception buffer is provided at each IP packet reception port.
When receiving the IP packet transmitted through the plurality of transmission systems from the IP packet receiving port connected to the reception FPU 3 of the corresponding transmission system, the reconstruction device 6 temporarily stores the IP packet in the common reception buffer. Then, each IP packet is combined according to the order information given to the IP packet as a system, and the data of the transmission target material is reconstructed (restored).

The flow of processing by the data transmission system of this example will be described.
FIG. 2 shows an example of the processing flow on the data transmission side.
The load balancer 5 divides the data of the material to be transmitted into predetermined units and converts them into IP packets (step S11).
Next, separately from the IP protocol, order information indicating the order of IP packets is given to each IP packet (step S12).

Next, each IP packet is cyclically distributed at a predetermined distribution ratio to the transmission FPUs 2 of a plurality of transmission systems as follows.
First, the transmission buffer at the IP packet transmission port corresponding to the transmission FPU 2 that has reached the distribution order is confirmed (step S13), and it is determined whether or not the transmission buffer is empty (step S14). As a result, if it is determined that there is a vacancy in the transmission buffer, the IP packet is output to this transmission buffer (step S15). On the other hand, if it is determined that there is no space in the sending buffer, the IP packet is output to the sending buffer at the IP packet sending / outlet corresponding to the sending FPU 2 in the next distribution order instead of the sending buffer (step S16). If there is no vacancy in the sending buffer in the next distribution order, the IP packet may be output to the first sending buffer found in the following distribution order.
The above steps S13 to S16 are repeated until all IP packets have been output (distributed) (step S17).

FIG. 3 shows an example of the processing flow on the data transmission side.
When the reconstruction device 6 receives an IP packet transmitted through a plurality of transmission systems from an IP packet receiving port corresponding to the reception FPU 3 of each transmission system (step S21), the received IP packet is temporarily stored in a common reception buffer. Accumulate (step S22).
After that, the process of taking the IP packet with the smaller numerical value of the order information out of the IP packets stored in the reception buffer and combining them in the order of the order information is performed until the reception buffer becomes empty (until all IP packets are combined). ) Repeat (step S23).

  As described above, in the data transmission system of this example, the load distribution device 5 has a transmission buffer for holding a transmission-waiting IP packet (an example of divided data) distributed to the transmission system for each transmission system. And a mechanism for excluding the transmission system from the distribution destination of the IP packet until there is an empty space in the transmission buffer for the transmission system when the transmission buffer for the transmission system is full. It has become.

As a result, even if there is no space in the transmission buffer associated with any of the transmission systems, as in the conventional example, the distribution of IP packets is delayed until the transmission buffer is free, and data transmission is delayed. Since the situation does not occur, wireless data transmission can be performed at high speed.
Therefore, for example, if the data transmission system of this example is incorporated into a news gathering system, the material recorded at the news gathering site can be transmitted at high speed, so that it is possible to perform high-resolution local news reporting that was previously done at a low resolution. As a result, the quality of the news can be improved. Moreover, the data transmission system of this example can be used for various applications that require high-speed transmission of a large amount of data to a remote place, in addition to transmission of news material.

Here, in the data transmission system of this example, considering that the transmission speed (link speed of the corresponding transmission FPU2 and reception FPU3) differs depending on the communication environment in each transmission system, the IP packet of each transmission system As the distribution ratio, a ratio corresponding to the transmission speed of each transmission system is set.
For this reason, according to the data transmission system of this example, data transmission can be performed by effectively using the transmission capability of each transmission system.

  In this example, the load balancer 5 is configured to automatically set the distribution ratio of IP packets upon receiving a link speed notification from each connected transmission FPU 2, but the present invention is not limited to this. For example, the IP packet distribution ratio may be set by receiving an input of the link speed from the user, or may be set by receiving the input of the IP packet distribution ratio itself from the user.

  In addition, each transmission system is a high-speed transmission system that prioritizes transmission speed over error generation suppression, a low-speed transmission system that prioritizes error generation suppression over transmission speed, a transmission system with an intermediate speed between them, Different transmission speeds may be intentionally set in each transmission system. As a result, for example, the maximum speed of data transmission can be realized in the case of a communication state in which errors are unlikely to occur.

  Also, even if the IP packet distribution ratio is set evenly without considering the transmission speed of each transmission system, the transmission buffer that has run out of space is temporarily (from the IP packet distribution destination until the space is available) ) Since it is excluded, it does not fall into the situation that the distribution of IP packets is delayed and the data transmission is delayed, but it is faster to set the distribution ratio according to the transmission ratio of each transmission system in advance. Can be realized.

  Further, the distribution of IP packets to each transmission system may be performed in units of one packet, or may be performed in units of a predetermined amount of IP packets. Note that in a configuration in which a predetermined amount of IP packets are distributed in a unit, if the amount of available IP packets is distributed to the transmission buffer when the transmission buffer is less than the predetermined amount, It may be temporarily excluded from the distribution destination, or it may be temporarily excluded from the distribution destination of the IP packet immediately without distributing the IP packet even if there is a vacancy in the transmission buffer.

  Note that the load distribution device 5 and the reconstruction device 6 in this example are realized by incorporating the above-described mechanism into the load distribution device 7 and the reconstruction device 8 in the conventional example, but the availability of equipment is high. The processing routine as described above may be incorporated into a general-purpose PC or the like.

The present invention can also be provided as a method and method for executing the above processing, a program for realizing such a method and method, a storage medium for storing the program, and the like.
In addition, the configuration of the system and apparatus according to the present invention is not necessarily limited to the above-described configuration, and various configurations may be used.

  The present invention can be used in various types of data transmission systems including a plurality of transmission systems for transmitting data wirelessly.

  1: camera, 2: transmission FPU, 3: reception FPU, 4: material reception equipment, 5: load distribution device, 6: reconstruction device

Claims (3)

In a data transmission system comprising a plurality of transmission systems for transmitting data wirelessly,
A load balancer that distributes each divided data obtained by dividing the data to be transmitted to the plurality of transmission systems;
The load balancer has a buffer that holds divided data waiting for transmission distributed to the transmission system for each transmission system, and when the buffer of any transmission system runs out of space, Excluding the transmission system from the distribution destination of the divided data until the buffer of the transmission system is vacant,
A data transmission system characterized by that. Each of the plurality of transmission systems performs transmission of divided data using an FPU,
The load distribution device distributes the divided data to the plurality of transmission systems at a ratio corresponding to the link speed of the FPU in each transmission system.
The data transmission system according to claim 1. A load distribution device that distributes each divided data obtained by dividing data to be transmitted to a plurality of transmission systems that transmit data wirelessly,
Each transmission system has a buffer for holding the divided data waiting for transmission distributed to the transmission system, and when the buffer of any transmission system runs out of space, the buffer of the transmission system is free The transmission system is excluded from the distribution destination of the divided data until
A load balancer.

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