JPH07212737A - Data transmitter - Google Patents

Abstract

PURPOSE:To transmit data in response to a request of each recipient even when plural recipients make different requests by sharing plural recipient requests to plural time slots and reading recording data from a recording medium for each time slot. CONSTITUTION:A data transmitter 1 selectively supplies program information sets SR1-SRk from a program library 2 via a switcher 3 to transmission sections 4A1-4A. The library 2 uses a cassette automatic changer to reproduce automatically a cassette based on a control signal S1 from a program control section 5 and outputs different program information simultaneously. A transmission section 4 once stores program information and it is read and outputted based on a control signal S3 of a program transmission control section 6. The program information from the transmission section 4 and the program information via a switcher 7 receive ID information corresponding to a recipient via formatters 8A1-8AL and 11A1-11AN and the resulting data are sent to each recipient via a data exchange 9 and a telephone line LIN.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. Field of Industrial Application Conventional Technology Problems to be Solved by the Invention Means for Solving the Problems (FIGS. 1 to 5 and 9) Action (FIGS. 1 to 5 and 9) Example (FIGS. 1 to 1) 9) Effect of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission device,
For example, it is suitable to be applied to a data transmission device that transmits video data according to a request of a receiver.

[0003]

2. Description of the Related Art Conventionally, as this type of data transmission device,
There are CATV (cable television) and a captain system using a telephone network. In CATV, a video tape recorder (VTR) which is a sequential access storage device is generally used to unilaterally provide a program to a receiver.

[0004]

By the way, in the CATV, as described above, the program information reproduced from the VTR is provided to a plurality of receivers, so that the receivers can receive the program information at a time desired by the receivers. However, there is still an insufficient problem in that the receiver cannot supply the desired program, and as a result, the demand of the receiver is satisfied. For example, even if the recipient selects the desired program, the recipient can view this program from the beginning because the program is unilaterally provided to multiple recipients regardless of the recipient's request. There was no inconvenience.

As one method for solving such a problem,
It is conceivable that the same number of VTRs and video tapes as the number of recipients are used to provide desired program information at a desired time of the recipients in response to the request from the recipients. However, there has been a problem that the operation cost will be large and the operation cost will be large.

It is also possible to provide program information according to the request of the receiver by combining a large-scale disk array and a high-performance workstation, but this method also has a problem that the configuration becomes very complicated. I got it. Further, in this method, a large margin is required for the storage device and the workstation in order to immediately respond to the requests of a large number of receivers and to secure a constant transmission rate, and the number of receivers that can be received at the same time. There is a problem that a large cost burden is required to remove the restriction of.

The present invention has been made in consideration of the above points, and is intended to propose a data transmission apparatus capable of providing program information according to the wishes of each receiver with a relatively simple structure. Is.

[0008]

In order to solve such a problem, according to the present invention, in a data transmission device 1 for transmitting data according to a request from a receiver via a predetermined transmission line LIN, a predetermined recording medium It has a recording / reproducing means 23 for recording and reproducing data on the above, and when reading the recorded data on the recording medium in response to a request from the receiver, requests from a plurality of receivers are sent to each time slot of a plurality of time slots. A data transmission unit 4 for reproducing a plurality of data according to requests from a plurality of recipients by distributing and reading record data from different recording areas of a recording medium for each time slot.
A ₁ to 4A _L, so as comprising a 10A ₁ 10 A _m.

Further, in the present invention, the data transmission section 4A
_{1 ~4A L,} 10A _{1 ~10A m} includes a recording medium, records the data on a recording medium, when reading the data recorded on the recording medium in response to a request from the recipient, a request for multiple recipients Recording / playback for playback of multiple data in response to the requests of multiple recipients by distributing the data to different time slots of multiple time slots and reading the recorded data from different recording areas of the recording medium at high speed for each time slot. Means 23 and data decompression means 21 for decompressing the data reproduced by the recording / reproducing means 23 are provided.

[0010] Furthermore, in the present invention, the data transmission device 1, a plurality of data transmission unit 4A ₁ to 4A _L, 10A ₁ ~
And 10A _m, the data transmission unit 4A ₁ to 4A _L according to the number of requests from the recipient, and a switcher 7 for selectively cascade connection between 10A ₁ 10 A _m, the first data transmission unit 4
A ₁ to 4A _L or 10A ₁ against 10 A _m data, the first data transmission unit 4A ₁ to 4A _L or 10A
₁ 10 A when the required has been made from the receiver over the output channel number of _m, the first data transmission unit 4A ₁ to 4A _L
Alternatively, a plurality of output channels (0 to 10A _{1 to} 10A _m
n), at least one of the second data sending unit 4A ₁
Connected to the input terminal of the to 4A _L or 10A ₁ 10 A _m, the first and second data transmission unit 4A ₁ ~4A _L, 10A ₁ ~
So as to send data from 10A _m.

Further, according to the present invention, the first data sending unit group 4 consisting of _one or a plurality of data sending units 4A _{1 to} 4A _L and one or a plurality of data sending units 10A _{1 to} 10A.
a second data transmitting unit group 10 consisting of _m, first arbitrary data transmitting unit 4A ₁ of the delivery unit group 4 of the to 4A _L-1 or 4A _L the data transmission unit 4A ₁ for the data to 4A _{L -1} or when a request from the recipient over the output channel number of 4A _L has been filed, the data transmission unit 4A ₁ ~4A _L-1 or 4
At least one of the plurality of output channels of A _L is connected to a predetermined data transmission unit 10A ₁ of the second data transmission unit group 10.
-10A _m-1 or 10A _m connected to the input end,
Arbitrary data transmission unit 10A of the second data transmission unit group 10
₁ when 10 A _m-1 or 10A _m requests from the data transmitting unit 10A ₁ 10 A _m-1 or recipients exceeds the output channel number of the 10A _m for the data has been made, the data transmission unit 10A ₁ -10A _m-1 or at least one of the plurality of output channels of 10A _m is used as another data transmission unit 10A _{1 to} 10A _m-1 of the second data transmission unit group 10.
Or a switcher 7 is connected to the input terminal of the 10A _m, subordinate connexion sequential data sending unit 10 in the number of recipients increases
The A ₁ 10 A _m so as to cascade connection.

[0012] Further, in the present invention, the data transmission device 1, the first data transmission unit 4A ₁ to 4A _L or 10A ₁
When the recipient requests is assigned to the last time slot of 10 A _m, the first data transmission unit 4A ₁ to 4A _L or 10A ₁ 10 A _m and the second data transmission unit 4A ₁ ~
4A _L or 10A _{1 to} 10A _m are connected in cascade to output the output data of the _first data sending units 4A _{1 to} 4A _L or 10A _{1 to} 10A _m to the second data sending units 4A _{1 to} 4A _L or 1.
Recording is started on a recording medium of 0A _{1 to} 10A _m .

Further, in the present invention, the data transmission device 1 is provided with a program library 2 capable of selectively reproducing desired program information from a plurality of program information, and the program information obtained from the program library 2 is sent to a data transmission section. 4A _{1 to} 4A _L-1 or 10A _L.

Further, in the present invention, the program library 2 is constituted by a video tape recorder, a disk reproducing device or a data recorder.

Further, in the present invention, the data transmission section 4
A ₁ to 4A _L and 10A ₁ 10 A _m as the recording medium, so that use magneto-optical disc, a magnetic tape, a semiconductor memory or disk array.

[0016] Further, in the present invention, the data transmission device 1, the data sending unit 4A ₁ to 4A _L and 10A ₁ to 10
The transmission data obtained from A _m is transmitted to the receiver via a telephone line, a cable television line or a satellite communication channel.

[0017]

In the present invention, a plurality of requests from a plurality of recipients are requested.
Distribute to each time slot of each time slot
Recording from different recording areas of the recording medium for each imslot
By sending data, the data sending unit
4A₁~ 4A_L10A ₁-10A_mRecording on the recording medium
Received data from different recipients
Even in the event of an accident, the transmission data according to each recipient's request
Can be provided.

[0018] In the present invention, a plurality of data transmission unit 4A ₁ to 4A _L, 10A ₁ provided 10 A _m, the output channel number of the first data transmission unit 4A ₁ to 4A _L or 10A ₁ 10 A _m when a request from the recipient has been made above, the first data transmission unit 4A ₁ to 4A _L or 10A ₁ ~
At least one of the output channels of 10A _m second
The data transmission unit 4A ₁ to 4A _L or 10A ₁ 10 A _m
Connected to the input end of the first and second data sending units 4A ₁
To 4A _L, 10A by ₁ it has from 10 A _m to send data, it is possible to easily increase the receivable number of recipients.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a data transmission apparatus as a whole, so that each receiver can be provided with desired program information such as a movie program in response to a reception request sent from the receiver via a telephone line LIN. Has been done. The data transmission device 1 uses the program information S _R1 and S _R1 obtained from the program library 2.
_R2 , ..., S _{R (k-1)} , S _Rk are passed through switch 3 to the first
Of the plurality of sending units 4A ₁ , 4A ₂ ,
..., selectively supplies to 4A _L-1, 4A _L.

Here, the program library 2 includes a plurality of VTRs.
And a cassette in which desired program information is recorded in each VTR is automatically loaded and reproduced on the basis of a control signal S1 from the program control section 5. Different program information S _{R1 to} S _Rk can be simultaneously output from each output channel. The switch 3 is a (k × L) matrix switch consisting of k inputs and L outputs.
The program information S _{R1 to} S _Rk sent from the program library 2
Selectively outputs the transmitting unit 4A ₁ to 4A _L in response to the control signal S2 from the program control unit 5.

Each of the sending units 4A _{1 to} 4A _L has one input channel and (n + 1) output channels. And each delivery section 4A ₁ to 4A _L has a large-capacity storage device,
The input program information is temporarily stored in a storage device, and is read out and output based on a control signal S3 from the program transmission control section 6. N number of delivery unit of _{4A 1 ~4A L (n + 1} ) number of output channels, together with allocated for the recipient, one output channel rest is connected to the switcher 7.

The program information output for the recipient from the sending unit 4A ₁ to 4A _L is Fuomatsuta 8A ₁ by ~8A _L, ID information corresponding to the recipient (identification information) followed with are additional data exchange 9 After being converted into a format suitable for the input format of, the data is provided to each recipient through the data exchange 9 and the telephone line LIN. As a result, in the data transmission device 1, for example, the sending unit 4A ₁
Can provide program information having the same content to n recipients, and, for example, from the sending unit 4A _L to the sending unit 4
Program information different in content from the program information of A ₁ can be provided to n recipients.

In addition, the data transmission device 1 includes a second sending unit group 1
0, and each of the second sending unit group 10 has a sending unit 4
A ₁ sending unit 10A ₁ to 10 comprising the same configuration as to 4A _L
It is composed of _Am . Each sending unit 10A _{1 to} 10A
_Of the (n + 1) output channels of _m , n are assigned for the receiver, and the remaining one output channel is connected to the switch 7. Sending part 10A ₁
The program information output for the receiver from -10A _m is added with ID information corresponding to the receiver by the formaters 11A _{1 to} 11A _m , and is converted into a format suitable for the input format of the subsequent data exchange 9. After that, it is provided to each recipient through the data exchange 9 and the telephone line LIN.

The switch 7 has a matrix structure of {(L + m) × m}, and by switching the connection based on the control signal S4 from the program sending control unit 6, the first sending unit group 4 and the second sending unit 4 can be sent. The program information output from the group 10 is transmitted to the second transmitting section 10 by the transmitting sections 10A _{1 to} 10A _m-1.
It is adapted to selectively supply or 10A _m.

As a result, in the data transmission device 1, as shown in FIG. 2, the sending units 4A ₁ to 4A of the _first sending unit group 4 are provided.
A sending unit 4A ₁ to 4 with respect to the program information of the _L-1 or 4A _L
If A _L-1 or 4A many requests one has not completely according to _L (i.e. n or more requests) is filed, a program information transmitting unit 4A ₁ to 4A _L-1 or 4A _L, once Empty sending units 10A _{1 to} 10A _{m-1 of} the second sending unit group 10
Or by providing through 10A _m, it can be the number of recipients may provide program information is doubled (2n people).

Further, the sending units 4A ₁ to 4 of the first sending unit group 4
To the program information A _L-1 or 4A _L, transmitting unit 4A ₁ ~
4A _L-1 or 4A _L and one sending unit 10A _{1 to} 10A _m-1 or 10A _m of the second sending unit group 10, a large number of requests that cannot be met by a total of two sending units (that is, 2n or more requests). ) is the case been filed, the second delivery portion 10A ₁ of the delivery unit group 10 10 a _m-1 or another delivery unit 10A ₁ to the subsequent 10A _{m ~10A m-1} or 10A _m to cascade connection As a result, the number of output channels of the program information is sequentially increased.

In this way, in the data transmission device 1, the transmission units 10A _{1 to} 10A _m-1 or 10A _{m that} are connected in series as the number of requests for certain program information increases.
By increasing the number of the receivers, the number of recipients that can receive at the same time can be increased by effectively using the sending unit.

Here, each sending section 4A ₁ of the first sending section group 4
4A _L and each sending unit 10A _{1 of} the second sending unit group 10
10A _m is configured as shown in FIG. That sending unit 4A ₁ to 4A _L and 10A ₁ 10 A _m are input to buffer memory 21 via the input INTERFACE 20 program information from the switcher 3 or 7. Sending unit 4A ₁ to 4A _L and 10A ₁ 10 A _m is the output of the buffer memory 21, INTERFACE for recording and reproducing 22
It is possible to record on a predetermined recording medium by the recording / reproducing unit 23 via the output interface 2 at the same time.
It is also possible to output from a plurality of output channels via 4.

In the case of the embodiment, a magneto-optical disk capable of recording program information for one movie, for example, is used as the recording medium, and the recording / reproducing unit 23 records the program information on this magneto-optical disk. A disk recording / reproducing device capable of high-speed reproduction is used. As a result, the recording / reproducing unit 23 can access a desired recording area of the recording medium at high speed and reproduce desired information at high speed in response to a request from a receiver.

The program information read from the recording / reproducing unit 23 is expanded in the time axis direction by the buffer memory 21 to be reduced to a predetermined transmission rate, and then is transmitted to a plurality of receivers (through the output interface 24). (n people or less). Incidentally, the write operation and the read operation of the program information by the recording / reproducing unit 23 are controlled by the CPU 26 using the ROM 25 and the RAM 27.

When the program information is already recorded on the recording medium, the recording / reproducing unit 23 divides the unit time (1 second in the embodiment) into n time slots, as shown in FIG. , Each time slot is distributed to each receiver, different positions of the recording medium are accessed at high speed for each time slot, and the recorded data at this position is read out at high speed, so that the same program can be sent to multiple receivers. Information is provided with a time lag.

As a result, in the data transmission device 1, the program information can be provided to each receiver from the beginning. That is, assuming that the unit time is T [seconds], the recording / reproducing unit 23 accesses the desired area of the recording medium at high speed at T / n [seconds], and the data for T [seconds] of one receiver is obtained. To play at high speed.

The recording / reproducing unit 23 also stores program information from the program library 2 on the recording medium or other transmitting units 4A _{1 to} 4A.
While recording the program information from _L , 10A _{1 to} 10A _m, it is also possible to send the program information with a time lag to each receiver. In this case, the recording / playback unit 23
As shown in FIG. 5, the unit time is divided into n time slots, of which (n-1) time slots are used to read the recorded data and the remaining one time slot is used for the program library 2 or Another sending section 4A ₁ to 4
A _L, the program information from the 10A ₁ 10 A _m recorded.

Here, the unit time is T (second), the recording / reproducing unit 2
The maximum access time to the recording medium of No. 3 is t _a (seconds), the data writing / reading rate of the recording / reproducing unit is r (bytes / second), and the amount of data sent to the receiver within the unit time T is d (bytes). ) and when, time slots number S of each delivery section 4A ₁ to 4A _L or 10A ₁ 10 a _m is expressed by the following equation,

[Equation 1] Can be selected.

[0036] In the data transmission apparatus 1, sending unit 4A ₁ to 4A _L, 10A ₁ to 10 A _m and cascade connection a plurality of delivery portions 4A ₁ to 4A _L, a number of via 10A ₁ 10 A _m When transmitting the transmission data to the receiver, the copying of the data from the transmitter of the former stage to the transmitter of the latter stage is started at the time when the n-th receiver requests the former transmitter.

As a result, in the data transmission device 1,
When the (n + 1) th recipient receives a reception request for the data of the sending section in the preceding stage, this recipient is assigned to the sending section in the subsequent stage to immediately request the recipient from the sending section in the subsequent stage. It is designed to be able to provide data according to.

Here, the schedule management unit 12 of the data transmission device 1 controls the entire data transmission device 1 by executing the processing procedure shown in FIG. That is, the schedule management unit 12 enters from step SP0,
When a reception signal S5 indicating a program request from the receiver is input from the data exchange 9 in step SP1, the program requested in step SP1 in the subsequent step SP2 is one of the sending parts 4A ₁ to 4A _{1 of} the first sending part group 4. 4AL _-1
Or it determines whether there in 4A _L.

The schedule managing unit 12 is step SP2.
When a positive result is obtained in step S3, the process proceeds to step SP3.
On the other hand, the schedule management unit 12 determines the step SP2.
If a negative result is obtained at step SP4, the program requested at step SP1 is transferred to step SP4 and the second transmission section group 1 is selected.
Any one of the transmission units 10A _{1 to} 10A _m-1 or 10A
It is determined whether or not _m is present, and if a positive result is obtained, the process proceeds to step SP3. The schedule management unit 12 is step S
At P3, the transmission section 4A ₁ in which the requested program is recorded
An empty time slot in to 4A _L or 10A ₁ 10 A _m assigned to the recipient.

The schedule management unit 12 continues to step S.
In P5, transmitting unit 4A ₁ which time slot is allocated in step SP3 to 4A _L or 10A ₁ 10 A
Fuomatsuta 8A ₁ ~8A _L or 11A ₁ corresponding to _m
After instructing the receiver ID and time slot number in ~11A _m, it proceeds to step SP6.

On the other hand, when the schedule managing unit 12 obtains a negative result in step SP4, it moves to step SP7 and sends the sending units 4A _{1 to} 4A _L-1 or 4A not used by the first sending unit group 4. _Judge whether there is _L ,
If an affirmative result is obtained here, the process proceeds to step SP8 to judge whether or not the output channel of the program library 2 is empty. Sukejiyuru management unit 12 moves connexion to step SP9 an affirmative result is obtained at step SP8, the first delivery portion 4A are vacant sending unit group 4 ₁ to 4A _L-1 or 4A
_The requested program is transferred from the program library 2 to _L , and the process proceeds to step SP6.

On the other hand, if the negative result is obtained at step SP7 or if the negative result is obtained at step SP8, the schedule management unit 12 moves to step SP10 and a message indicating that the service cannot be performed due to congestion. Is sent to the reception requester via the data exchange 9, and then the process proceeds to step SP6. In step SP6, the schedule management section 12 fetches the management information obtained from the program control section 5 and the program transmission control section 6, and then the step S
The process returns to P1 and the above process is repeated.

The program control section 5 includes a schedule management section 12
By executing the processing procedure as shown in FIG. 7 on the basis of the control signal from the control unit 1, the program library 2 and the switcher 3 are controlled to output the transmission units 4A _{1 to} 4A of the _first transmission unit group 4.
Program information is selectively transferred to _L.

That is, the program control section 5 determines the step SP1.
The control signal S1 is entered from step 1 to determine whether or not there is an instruction from the schedule management section 12 at step SP12, and if a positive result is obtained here, the procedure moves to step SP13 to transfer the requested program. Is sent to the program library 2. Next, the program control unit 5 proceeds to step S
In P14, with respect to the switcher 3, after instructing the connection of the input channel request program output channels and free delivery section 4A of the program library 2 are output ₁ to 4A _L-1 or 4A _L, proceeds to step SP15.

On the other hand, if the program controller 5 obtains a negative result in step SP12, it moves to step SP15. In step SP15, the program control unit 5 sends the program library 2 and switch 3 to the schedule management unit 12.
When the management information is transmitted, the process returns to step SP12 and the above-mentioned processing is repeated.

The program transmission control section 6 executes the processing procedure as shown in FIG. 8 based on the control signal from the schedule management section 12 to make the switcher 7 and the transmission section 4 operate.
A ₁ to 4A _L, to control 10A ₁ 10 A _m. That is, the program transmission control unit 6 enters from step SP20,
Sending unit 4A program information of the program library 2 from Sukejiyuru management unit 12 in step SP21 ₁ ~4A _L-1
Or 4A _L is determined whether an instruction has been made to transfer, moves to where a negative result is obtained step SP22. On the other hand, when a positive result is obtained in step SP21, the instructed sending unit 4A is supplied in step SP23.
After giving an instruction for inputting program information from the program library 2 to ₁ to 4A _L-1 or 4A _L, proceeds to step SP22.

In step SP22, the program transmission control unit 6 sends from the schedule management unit 12 to the transmission units 4A _{1 to} 4A.
_It is judged whether or not there is an instruction to assign the receiver to _L or 10A ₁ to 10A _m , and if a negative result is obtained here, the process proceeds to step SP24 and all the sending units 4A _{1 to} 4A _L.
And information of 10A _{1 to} 10A _m . Proceeds to step SP25 when a positive result in step SP22 is obtained contrary, indicated delivery section 4A ₁ to 4A _L
Alternatively, it instructs 10A _{1 to} 10A _m to output data by using the empty time slot.

The program transmission control unit 6 continues the step SP26.
At step SP25, the sending unit 4A ₁ instructed
To 4A _L or 10A ₁ 10 A _m delivery unit 4A or is entering a port of the same program, ₁ to 4A _L or 10A ₁ 10 A
_It is determined whether or not there is a vacant time slot in _m, and if a positive result is obtained here, the process proceeds to step SP24, whereas if a negative result is obtained at step SP26, the process proceeds to step SP27. The program transmission control unit 6 is a step SP.
27, sending units 4A _{1 to} 4A not used
_L-1 or 4A _L is determined whether or not the present, where a negative result is obtained proceeds to step SP14, proceeds to an affirmative result is obtained step SP28 contrast.

[0049] In the program sending control unit 6 step SP28, by sending a control signal S4 to the switcher 7, transmitting unit 4A ₁ instructed to 4A _L or 10A ₁ to 1
The 0th output channel of 0A _m is set to the empty transmission section 10A ₁ to 1
Instructing to connect the input channel of 0A _m. In this way, the program transmission control unit 6 is connected to the step SP25-S.
In P28, sending unit 4A ₁ to 4A _L or 10A ₁ ~
If the output channel of 10A _m can not completely according to the received request, sending unit 4A ₁ to 4A _L or 10A ₁ 10 A _m
The number of output channels is increased by successively connecting the sending units 10A _{1 to} 10A _m in the subsequent stage.

The program sending control unit 6 continues the step SP24.
In, all the sending units 4A _{1 to} 4A _L and 10A ₁ to
After capturing information 10A _m, when sent to Sukejiyuru managing unit 12 information taken in step SP24 as the management information at step SP29, step SP
Returning to step 21, the above-mentioned processing is repeated.

In the above configuration, when there is a program request from the first receiver, the data transmission device 1 first sends the sending section 4A.
₁ to 4A _L or 10A ₁ determines whether there is the program to 10 A _m, either sending unit 4A ₁ to 4A _L or 1
0A ₁ 10 A if there has been a demand programs _m allocates a recipient to the sending unit 4A ₁ to 4A _L or 10A ₁ 10 A _m of free time slot.

On the other hand, which of the sending units 4A _{1 to} 4A _L
Or if there is no requested program in 10A _{1 to} 10A _m ,
Sending units 4A _{1 to} 4A _{L in an} empty state from the program library 2
Or 10A ₁ while copying and forwarding the request programs 10 A _m, the transmitting unit 4A ₁ to 4A _L or 10A ₁ to 10
The requested program is sent from A _m to the first receiver.

Further, in the data transmission device 1, when a request for the same program is made by the second receiver with a time difference from the first receiver, the second receiver is assigned to the first receiver. and transmitting unit 4A ₁ to 4A _L or 10A ₁ to 10
Assigned to another time slot of the A _m. At this time, in the data transmission device 1, at each time slot, the recording position corresponding to the time when the program request is made is accessed at high speed and the recorded data is read out at high speed. As a result, the data transmission device 1 can provide program information with a time lag according to the request time to a plurality of receivers.

[0054] In the data transmission apparatus 1, one transmitting unit 4A for a given program ₁ to 4A _L or 10A ₁
When the program requests that can not response at 10 A _m has been made, i.e. sending unit 4A ₁ to 4A _L or 10A ₁ if 10 A _m time slots the number of programs such requests exceeds the assigned unit time within T in has been made The sending units 4A ₁ to 4
The program information of A _L or 10A _{1 to} 10A _m is transmitted to another transmission unit 10A _{1 to} 10A _m-1 or 10A _m of the second transmission unit group 10.
To the sending unit 10A _{1 to} 10A _m-1 or 10A
Providing program information to the recipient via _m .

As a result, in the data transmission device 1, 1
One of the delivery portion 4A ₁ even to 4A _L or 10A ₁ 10 A when _m program requests that exceed the capability of has been filed, effective number of utilizing different delivery section 10A ₁ 10 A _m-1 or 10A _m The same program information can be provided to the receiver with a time lag, and the limit on the number of receivable receivers can be eliminated.

According to the above configuration, the sending units 4A _{1 to} 4A
_The program information is once recorded in _L or 10A _{1 to} 10A _m , and when the program information is read out, the request from the receiver is distributed to each time slot of a plurality of time slots,
Even if there is a request for a program with a time difference from each receiver, high-speed access to different recording areas of the recording medium and high-speed reading of the recorded data are performed for each time slot. The data transmission device 1 that can provide information to each receiver can be realized.

Further, one sending unit 4A _{1 to} 4A _L or 10
A ₁ in the case 10 A number of program requests that can not be according the _m has been made, sending unit 10A ₁ 10 A, depending on the number of programs required
_{Since m} is sequentially connected in series, the sending unit 4
A ₁ to 4A can be effectively used _L and 10A ₁ 10 A _m, it can be realized simplified data transmission device 1 of the resulting configuration.

In the above embodiment, the plurality of data sending units 4A _{1 to} 4A _L and 10A _{1 to} 10A _m are provided as the first.
Divided data transmitting unit group 4 of the second delivery unit group 10, sending unit 4A ₁ of either the first delivery unit group 4 or the second delivery unit group 10 to 4A _L or 10A ₁ 10 A _m When there is a reception request exceeding the number of output channels, the empty transmitters 10A ₁ to 10A _{1 of} the second transmitter group 10 through the switcher 7
The case where the number of receivable recipients is increased by connecting 10A _m-1 or 10A _m in the subsequent stage has been described.
The present invention is not limited to this, as shown in FIG. 9, a sending unit group constituted by a single delivery unit group 4, sending portion 4A ₁ to 4A _L
Via the switcher 31 in accordance with the empty state of, it may be cascade connection between sending portions 4A ₁ to 4A _L with connecting sending unit 4A ₁ to 4A _L and program library 2.
In this case, the switch 31 is {(k + L) × L}.
You can use the Matrices switch of.

Further, in the above embodiment, the sending section 4A
₁ to 4A using the magneto-optical disc as a recording medium _L and 10A ₁ 10 A _m, using a disc recording and reproducing apparatus capable of high-speed reproduction it is possible to record a program information as the recording and reproducing unit 23 in the magneto-optical disc Although the case has been described, the present invention is not limited to this, and the sending units 4A _{1 to} 4A _L are not limited to this.
And the recording medium 10A ₁ 10 A _m, a magnetic tape, it is possible to use a semiconductor memory or disk array, etc., a video tape recorder as the recording and reproducing unit 23 in response to this, the memory controller or disk reproducing device Various recording media and recording / reproducing units 23 that can be used and are capable of high-speed access and high-speed reading
Can be applied.

Furthermore, in the above-mentioned embodiment, the case where the cassette auto-chassis equipped with a plurality of video tape recorders is used as the program library 2, but the present invention is not limited to this, and the program library 2 is not limited to this. Can have various configurations such as a disk reproducing device or a data recorder.

Further, in the above-mentioned embodiment, the case where the transmission data obtained by the data transmission device 1 is transmitted to the receiver via the telephone line LIN has been described, but the transmission line is not limited to this, and the cable television is not limited to this. Various transmission lines such as a line or a satellite communication line can be used.

Further, in the above-mentioned embodiment, by reading the record data from the position corresponding to the time required by the receiver for each time slot assigned to each receiver,
The case where the program information is provided from the beginning to all the recipients has been described. However, the present invention is not limited to this, and when the recipients request to view the program information in the middle, the request information is responded accordingly. If the read position is selected, the program information can be provided from the position according to the desire of each receiver.

Further, in the above-mentioned embodiment, when reading out the data according to the request of each receiver for each time slot, the recording / reproducing unit 23 reads out the recorded data at a high speed, and then the data is expanded in the buffer memory 21. However, the present invention is not limited to this, and if the program information of the program library 2 is compressed and recorded in the time axis direction by the recording / reproducing unit 23 in advance, it is necessary to read the recorded data at high speed. Absent.

[0064] Further, in the aforementioned embodiment, the present invention has dealt with the case of applying to the data transmission apparatus 1 for transmitting program information from the program library 2, the data transmitting unit 4A ₁ to 4A _L and 10A ₁ ~ The data transmitted from 10A _m is not limited to the program information, but the data transmission units 4A ₁ to 4A 4
Also transmitting the data other than the program information via the A _L and 10A ₁ 10 A _m can be obtained the same effect as the above-described embodiment.

[0065]

As described above, according to the present invention, the recording / reproducing means for recording and reproducing the data on the predetermined recording medium is provided, and the recorded data on the recording medium is read out in response to the request from the receiver. At this time, the requests of a plurality of recipients are distributed to the respective time slots of a plurality of time slots, and the recorded data is read from different recording areas of the recording medium for each time slot, thereby making it possible to respond to the requests of the plurality of recipients. By providing the data transmission section for generating the data of 1., it is possible to realize the data transmission apparatus capable of providing the program information according to the desire of each receiver with a relatively simple configuration.

Further, according to the present invention, a plurality of data transmission units are provided, and when the number of output channels of the first data transmission unit exceeds the number of requests from the receiver, the output channels of the first data transmission unit are changed. By connecting at least one of them to the input terminal of the second data sending unit and sending the data from the first and second data sending units, the transmission data can be sent to a large number of receivers with a simple configuration. A data transmission device that can be provided can be realized.

[Brief description of drawings]

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

FIG. 2 is a block diagram provided for explaining a case where a sending unit is connected in cascade.

FIG. 3 is a block diagram showing a configuration of a sending unit.

FIG. 4 is a time chart used for explaining a read operation of the sending unit when the sending unit has desired recording data.

FIG. 5 is a time chart used for explaining a data writing operation and a data reading operation by the sending unit when there is no desired recording data in the sending unit.

FIG. 6 is a flowchart showing a processing procedure of a schedule management unit.

FIG. 7 is a flowchart showing a processing procedure of a program control unit.

FIG. 8 is a flowchart showing a processing procedure of a program transmission control unit.

FIG. 9 is a block diagram showing a data transmission device according to another embodiment.

[Explanation of symbols]

1, 30 ... Data transmission device, 2 ... Program library,
3, 7, 31 ... Switcher 4,10 ... Sending unit group,
_{4A 1 ~4A L, 10A 1 ~10A} m ...... sending unit, 21
...... Buffer memory, 23 ...... Recording / playback unit, LIN
telephone line.

Claims (9)

[Claims] 1. A data transmission apparatus for transmitting data in response to a request from a receiver via a predetermined transmission path, comprising recording / reproducing means for recording and reproducing the data on a predetermined recording medium, When reading the recorded data on the recording medium according to the request from the recording medium, the requests of a plurality of recipients are distributed to each time slot of a plurality of time slots, and the recording is performed from a different recording area of the recording medium for each time slot. A data transmission device comprising a data transmission unit that generates a plurality of data in response to requests from a plurality of recipients by reading the data. 2. The data transmission section records a data on a recording medium and the recording medium, and, when reading the recorded data on the recording medium in response to a request from the recipient, requests from a plurality of recipients. Is distributed to each time slot of a plurality of time slots, and the recorded data is read out at high speed from different recording areas of the recording medium for each time slot, thereby reproducing a plurality of data according to the requests of a plurality of receivers. The data transmission device according to claim 1, further comprising a recording / reproducing unit and a data decompressing unit for decompressing the data reproduced by the recording / reproducing unit. 3. A plurality of data transmission units, and a switcher for selectively and continuously connecting the data transmission units in accordance with the number of requests from a receiver, for the data of the first data transmission unit. Then, when there is a request from the receiver exceeding the number of output channels of the first data transmission section, at least one of the plurality of output channels of the first data transmission section is set to the second data transmission section. 2. The data transmission device according to claim 1, wherein the data transmission device is connected to an input terminal of and the data is transmitted from the first and second data transmission units. 4. A first data transmission section group comprising one or a plurality of the data transmission sections, a second data transmission section group comprising a single or a plurality of the data transmission sections, and the first transmission section group. When there is a request from the receiver for the data of any of the data transmission units exceeding the number of output channels of the data transmission unit, at least one of the plurality of output channels of the data transmission unit is set to the second From a receiver which is connected to the input terminal of a predetermined data transmission unit of the data transmission unit group, and which exceeds the output channel number of the data transmission unit for the data of any data transmission unit of the second data transmission unit group. And a switch for connecting at least one of the plurality of output channels of the data transmission unit to the input end of another data transmission unit of the second data transmission unit group, Data transmission device according to claim 1, characterized in that the cascade connection the Supporting connexion sequentially the data sending unit to the number increases. 5. The data transmission device continues the first data transmission unit and the second data transmission unit when a receiver request is assigned to the last time slot of the first data transmission unit. 4. The data transmission apparatus according to claim 3, wherein the data transmission device is connected to start recording the output data of the first data transmission unit on the recording medium of the second transmission unit. 6. The data transmission device comprises a program library capable of selectively reproducing desired program information from a plurality of program information, and transfers the program information obtained from the program library to the data sending section. The method according to claim 1, wherein
The data transmission device described in 1. 7. The data transmission device according to claim 6, wherein the program library is constituted by a video tape recorder, a disk reproducing device or a data recorder. 8. The data transmission device according to claim 1, wherein the data sending unit uses a magneto-optical disk, a magnetic tape, a semiconductor memory or a disk array as the recording medium. 9. The data transmission device according to claim 1, wherein the transmission data obtained from the data transmission unit is transmitted to a receiver via a telephone line, a cable television line, or a satellite communication path. The described data transmission device.