JP2606593B2 - Command transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a command transmission system, and more particularly to a command transmission system which is difficult to retransmit, such as a remote control command having a real-time property and a command for a remote device such as a deep space probe.

[0002]

2. Description of the Related Art In a command transmission technique to space equipment, which is one of the conventional command transmission methods, there are about one transmission line, and one or at most two Transmission is performed using an error correction method, and when an error on a line increases, retransmission is used to cope with the error.

[0003]

In such a conventional command transmission method, rendezvous docking required for future space equipment, real-time remote operation from the ground such as a space robot, and remote control such as a deep space probe are required. In a control that requires a very long time for command transmission due to the distance, there is no other way but to cope with a data error on the line by retransmitting the command. However, such a retransmission method lacks real-time properties, takes a long time to check the operation,
There is a disadvantage that the amount of work that can be operated / controlled within a certain time is limited.

[0004] In addition, there is also a problem that, for a command that needs to be transmitted continuously, an erroneous command is lost and lacks continuity.

Accordingly, the present invention has been made to solve the problems of the prior art, and aims at smooth operation of a robot arm or the like without erroneous commands and deep space exploration. It is an object of the present invention to provide a command transmission system which enables reliable control in a device.

[0006]

According to the present invention, there is provided a command transmission system for transmitting and receiving command information, comprising: a plurality of encoding means for encoding the command information in accordance with different error detection and correction schemes; A command transmitter having a plurality of modulating means provided for each encoding means and modulating the output of the corresponding encoding means, and a multiplexing means for multiplexing and transmitting each modulation output of the modulating means. A command transmission system characterized by including:

Further, according to the present invention, separating means for receiving and separating multiplexed transmission information from the command transmitter,
A command receiver having a plurality of demodulating means for demodulating these separated outputs, respectively, and a plurality of decoding means provided in correspondence with these demodulating means and performing decoding based on an error detection and correction method of the corresponding demodulated output; A command transmission system characterized by the above feature is obtained.

[0008]

The commands to be transmitted are simultaneously encoded and transmitted in a multiplexed manner with different error detection and correction methods, and the receiving side separates the multiplexed command and performs error detection and correction in each error detection and correction method. Decoding is performed to selectively derive an error-free command.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a system block diagram of an embodiment of the present invention. In the transmitting unit on the ground side, the command generator 1
The same command generated from a plurality of encoders 21 to
2n. These plural encoders 21 and 2
n encodes an input command according to different types of error detection and correction schemes. For example, ECC according to each scheme is generated and added to the command to derive the command.

Modulators 31 to 3n are provided corresponding to these encoders 21 to 2n, respectively. These modulators modulate the outputs of the corresponding encoders by a predetermined modulation method and output the modulated signals. To the vessel 4 respectively. The multiplexer 4 multiplexes the plurality of modulated outputs by a predetermined multiplexing method and transmits the multiplexed output to the onboard side of a space device or the like via the transmitter 5.

On the on-board side, command information received by the receiver 6 is separated by the demultiplexer 7 and input to the demodulators 81 to 8n, respectively. These demodulators 81
8n are provided corresponding to the encoders 21 to 2n on the transmission side, and their demodulated outputs are applied to correspondingly provided decoders 91 to 9n, respectively.

In these decoders, the ECC of the corresponding demodulated output is
, A decoding process for error detection and correction of the demodulated data is performed, and supplied to the command decoder 10 to decode the command data.

In this case, the command decoder 10 receives the error correction results from the decoders 91 to 9n, determines a normal command, and selectively supplies only this normal command to each on-board device (not shown). It is supposed to. In this case, it is preferable to use a majority theory as a selection theory of a normal command.

As examples of the error detection and correction method in the encoders 21 to 2n, various known methods can be used. For example, a CRC (Cyclic Red) is used.
Random Check Code), a Hamming code, an extended Hamming code, a cyclic Hamming code, a group count check code, a Reed-Solomon code, and the like.

As a modulation method, in addition to ASK (amplitude shift keying), FSK (frequency shift keying), PSK (phase shift keying) which are generally used in digital satellite communication, and a modulation method combining these elements For example, a frequency multiplexing method can be adopted as the multiplexing method.

[0017]

As described above, according to the present invention, the same command is encoded and multiplexed and transmitted on the ground side using different ECC systems, and a correct command without errors is received on the receiving side such as a space device. By selecting and deriving,
There is no dropout of continuous remote control commands, and control in telescience has the effect of enabling smooth operation of robot arms, etc., and in particular, deep space probes enable reliable control. is there.

Also, compared to the conventional method using a single error detection and correction method, it is possible to transmit a command to a space device or the like more reliably, and the reliability of command transmission is greatly improved. There is also.

[Brief description of the drawings]

FIG. 1 is a system block diagram of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Command generator 4 Multiplexer 5 Transmitter 6 Receiver 7 Demultiplexer 10 Command decoder 21-2n Encoder 31-3n Modulator 81-8n Demodulator 91-9n Decoder

Claims (4)

(57) [Claims] 1. A command transmission system for transmitting and receiving command information, comprising: a plurality of encoding means for encoding the command information in accordance with different error detection and correction schemes; and a plurality of encoding means provided for each of the encoding means. A command transmission system, comprising: a command transmitter having a plurality of modulating means for modulating outputs of corresponding encoding means and multiplexing means for multiplexing and transmitting respective modulation outputs of the modulating means. 2. A demultiplexing means for receiving and demultiplexing multiplexed transmission information from the command transmitter, a plurality of demodulation means for demodulating these demultiplexed outputs, respectively, and a plurality of demodulation means respectively provided corresponding to the demodulation means. 2. The command transmission system according to claim 1, further comprising a command receiver having a plurality of decoding means for performing decoding based on an error detection and correction method of a corresponding demodulated output. 3. The command transmission system according to claim 2, wherein said command receiver further comprises a selection unit for selectively outputting a normal command from outputs of said plurality of decoding units. 4. The command transmission system according to claim 3, wherein said selecting means determines a selected output based on a majority rule of outputs of said plurality of decoding means.