JPH09284260A - Data transmission method and data transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance more the effect of correction by majority decision by differentiating an arrangement of respective packet data included in a corresponding block of multiplexed data from an arrangement of packet data in other blocks. SOLUTION: A multiplexer circuit 6 of a transmitter 2 acquires in the same timing three sets of data read through three read lines 7-9 in different timings and arranges three-sets of packet data from the read lines 7-9, e.g. at random to generate a basic series. A memory 12 of a receiver 2 of a data transmission system stores tentatively data from three write lines 15-17, a majority decision circuit 14 reads packet data through three read lines 18-20 in different timings and identifies and outputs single packet data sharing the majority in the read packet data to be identical. Then a read control section 13 reads the data through the read lines 20, 19, 18 while delaying timings sequentially.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital data transmission technique, and more particularly, to a technique for enabling correct reproduction of data being transmitted even if a part of the data is destroyed by noise from the outside or the like. Regarding

[0002]

2. Description of the Related Art In recent years, with the spread of multimedia technology, a plurality of types of data are frequently transmitted between physically separated transmission devices. Especially recently
There is a tendency for the amount of data to be transmitted to increase, and how to increase the transmission speed has become important. In order to transmit a large amount of data faster, it is necessary to accurately transmit individual data and to be able to correctly reproduce even if there is an error.

Conventionally, various data correction means have been proposed for coping with the case where data is destroyed due to some cause such as electric wave, static electricity, noise such as shock during data transmission. One of the effective methods is a means for multiplexing and transmitting data to be transmitted, and after the transmission, demultiplexing and reproducing the data to be transmitted.

The data correction means using this multiplexed data specifically comprises the following elements. First, in the transmitter, a plurality of packet data included in the data to be transmitted are sequentially multiplexed a plurality of times according to a fixed arrangement rule to generate multiplexed data, which is sent to the transmission path. In the receiving device,
By selecting the single packet data that occupies the largest number from the plurality of packet data groups that should be the same in the multiplexed data, the data error that occurred during the data transmission process is corrected.

In such a data correction means, noise is suddenly generated during transmission, noise having a cycle of multiplexed data (a plurality of packet data is multiplexed in each cycle), or the like is multiplexed. When the data is destroyed, the transmitted data can be effectively reproduced and received. A technique related to this is described in detail in Japanese Patent Publication No. 1-16968.

[0006]

In the technique described in the above publication, since a certain arrangement rule is used when multiplexing a plurality of packet data included in transmission target data, the multiplexed data is , The same packet data is included in a fixed cycle. Therefore, when noise having a cycle approximately equal to the cycle interval in which the same packet data appears in the multiplexed data over a relatively long time, all the specific data included in the multiplexed data may be destroyed. There was a problem.

Further, when the packet is damaged by this kind of noise during transmission, when selecting a single packet data which is considered to be correct by the majority decision in the receiving device, all the packet data to be majority decided are incorrect. There is also a problem that the data cannot be corrected correctly.

An object of the present invention is to destroy all the same packet data repeatedly included in the multiplexed data even when sudden noise as well as periodic noise occurs to some extent during the transmission processing of the data to be transmitted. It is to provide a technique for suppressing the probability of being made and making the correction by majority voting more effective.

[0009]

In order to solve the above problems, the present invention provides an improved data transmission method and data transmission system. The data transmission method of the present invention comprises the steps of multiplexing the same transmission target data composed of a plurality of packet data N times and transmitting multiplexed data in which a maximum of N packet data are arranged for each block, Upon receiving the data, the packet data that occupies the largest number among the subsequent N blocks starting from the individual blocks is specified from the received multiplexed data, and the specified packet data is assembled in block order to reproduce the transmission target data. And stages. Then, the array of individual packet data included in the corresponding block of the multiplexed data is made different from the array of packet data in other blocks. This sequence may be random.

In the data transmission system of the present invention, the same transmission data composed of a plurality of packet data is multiplexed N times to generate multiplexed data in which a maximum of N packet data are arranged in each block. The transmitter is provided and the receiver receives the multiplexed data generated and transmitted by the transmitter. The multiplexing means included in the transmitting device is configured to make the arrangement of the individual packet data included in each block different from the arrangement of the packet data in other blocks when generating the multiplexed data.

[0011]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block configuration diagram of a data transmission system 1 according to an embodiment of the present invention.
This data transmission system 1 includes a transmitter 2 and a receiver 3.
It is composed of

The transmitter 2 reads the memory 4 for storing the data to be transmitted composed of a plurality of packet data and the data of the same content stored in the memory 4 by, for example, three read lines 7 to 8 to read one data. And a multiplexing circuit 6 for generating the multiplexed data of. When the same data stored in the memory 4 is read from the three read lines 7 to 8, the read control unit 5 instructs the memory 4 to read each read line. In the present embodiment, this timing is set to the read lines 7, 8, 9
In this order, the same packet data is read while delaying the timing.

The function of the read control unit 5 will be described in more detail with reference to FIG. Memory 4 of read control unit 5
In response to a read instruction to the read data, the read data from the read line 7 is a packet of continuous data A, B, C,
The order is D, E, F ,. Further, the read timing of the read line 8 is one behind the read timing of the read line 7, and the read timing of the read line 9 is one behind the read timing of the read line 8.

The multiplexing circuit 6 acquires the three data read at different timings on these three read lines 7, 8, 9 at the same timing. The three packets acquired at this time are arranged, for example, in random order following the packet data from the read line 7 and the packet data from the read lines 8 and 9 to generate one basic sequence consisting of three packets. Such data processing is continuously performed to generate one multiplexed data.

On the other hand, the receiver 2 of the data transmission system 1
Receives the multiplexed data from the three write lines 15-1.
7, a memory 12 for temporarily storing and storing data from the three write lines 15 to 17 from the separation circuit 11, and three read lines 1 from the memory 12.
8 to 20, packet data is read at different timings, and a majority circuit 14 is provided for identifying and outputting a single packet data that occupies the majority among the read packet data to be the same.

The separating circuit 11 has a function of returning the data multiplexed by the multiplexing circuit 6 to the state before the multiplexing. The read control unit 13 controls the timing of reading the data stored in the memory 12, and reads the data from the read lines 20 to 19 and 18 with the timing sequentially delayed. This is to make the progress of each packet data shifted by the reading by the control unit 5 the same. For this reason,
The majority circuit 14 can receive packet data that should be the same at the same timing.

The transmission data correction function according to this embodiment will be described in detail with reference to FIGS. 3 and 4. 3A to 3C, the multiplexed data according to the conventional example and the multiplexed data according to the present embodiment have the same three types of noises, that is, sudden burst noise and the same multiplexing period. It is shown that packet data is destroyed by periodic noise having a period and beat noise composed of pulses having intervals different from the multiplexing period. A characteristic of FIG. 3C is that only certain packet data, here A and E, included in the multiplexed data are destroyed by the burst noise. FIG.
FIG. 6 is an explanatory diagram showing correctability when the multiplexed data of the conventional example and the multiplexed data of the present embodiment are destroyed by the noises.

Burst noise as shown in FIG. 3A is generated suddenly. If several consecutive bits of the multiplexed data are destroyed by this kind of noise, if the packet data with the same content as the destroyed packet data remains in the multiplexed data without being destroyed, the conventional example Also, in the case of the present embodiment as well, it is possible to correctly reproduce the transmission target data (circle mark in FIG. 4).

The periodic noise as shown in FIG. 3 (b) destroys each packet data at a period equal to the multiplexing period. Also in this case, if the destroyed packet data is left in the multiplexed data without being destroyed, the transmission target data can be reproduced in both the conventional example and the present embodiment (see FIG. 4). ○).

The beat noise as shown in FIG. 3 (c) consists of pulses at intervals different from the multiplexing period. Among them, there is one that destroys only a specific packet of multiplexed data in the conventional example. Exists. Even if such destruction by packet data is encountered, since the arrangement rule at the time of multiplexing is random in the present embodiment, all of the same packet data included in the multiplexed data will not be lost by destruction. .

In this embodiment, the number of readings and the number of writings are limited to three, but the present invention can be similarly applied to a case where the number of readings and writings exceeds three. For the same data destruction in principle, the correction capability can be enhanced as the number of data is increased. Also, randomizing the array of packet data for each block
From the viewpoint of simplification of the system configuration, it is desirable to perform the transmission on the side of the transmission device 2, but it is also possible to provide a reception buffer in the reception device 3 to temporarily store the multiplexed data, and to perform similar processing at the time of reading. It is possible.

[0022]

As is apparent from the above description, according to the present invention, when the multiplexed data is continuously destroyed by several bits due to noise during its transmission, or when the multiplexed data has a period different from the multiplexing period. Even if the data is destroyed by beat noise having noise, or even if it is destroyed by burst noise, there is an effect that the transmission target data can be correctly reproduced by the receiving device.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a data transmission system according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a structure of multiplexed data according to the present embodiment.

3A and 3B are explanatory diagrams showing a noise state and a possibility of error correction in a conventional example and the present embodiment, in which (a) is burst noise, (b) is periodic noise, and (c) is beat noise. Shown respectively.

FIG. 4 is an explanatory diagram showing correctability when the multiplexed data of the conventional example and the multiplexed data of the present embodiment are destroyed by the noises.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 data transmission system 2 transmitter 3 receiver 4 12 memory 5 13 read controller 6 multiplex circuit 11 separation circuit 14 majority circuit 7-9, 18-20 read line 15-17 write line 21 transmission path

Claims (3)

[Claims] 1. A step of multiplexing the same transmission target data composed of a plurality of packet data N times (a natural number of 2 or more) and transmitting multiplexed data in which a maximum of N packet data are arranged for each block, When the multiplexed data is received, the packet data that occupies the largest number among the subsequent N blocks starting from each block is specified from the received multiplexed data, and the specified packet data is assembled in the order of blocks to transmit the target data. And the step of reproducing the packet data in the corresponding block of the multiplexed data is different from the packet data array in another block. 2. The data transmission method according to claim 1, wherein the arrangement of the packet data is random. 3. A transmission device comprising a multiplexing means for multiplexing the same transmission target data composed of a plurality of packet data N times to generate multiplexed data in which a maximum of N packet data are arranged for each block. A means for receiving the multiplexed data, a means for identifying the packet data that occupies the largest number among the subsequent N blocks starting from individual blocks from the received multiplexed data, and assembling the identified packet data in block order And a receiving device having a unit for reproducing the transmission target data, wherein the multiplexing unit includes an array of individual packet data included in a corresponding block of the multiplexed data and an array of packet data in another block. A data transmission method characterized by differentiating.