JPH01174040A - Data transmission equipment - Google Patents

Abstract

PURPOSE:To simultaneously transmit a data from a control station to plural transmission stations by setting the delay time of a data in response to the delay time of a line connected to the plural transmission stations. CONSTITUTION:A control station C0 sends a measuring signal to transmission stations T01-T0n via a line 15, counts the delay time of said line 15 based on the delay time of a transmission/reception signal and sets the correction data of the line 15 to a delay setting section 26. In the mode sending the data to the transmission stations T01-T0n, the switch 13 of the control station C0 is changed over to connect the incoming side of the data 14 and the line 15. A data 14 is sent to the transmission stations T01-T0n via a modulator 12, the switch 13 and the line 15 and demodulated by a demodulator 23. The demodulation data is delayed in response to the correction data set in the delay setting section 26 and sent to a receiver 30 via a transmitter 27 and an antenna 28.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a data transmission device used in a paging system or the like using wired lines and wireless lines.

Conventional technology In general, data transmission devices such as paging systems, etc.
In order to prevent soft errors, each transmitting station is configured to transmit data to one receiver at the same time.

As shown in FIG. 2, in the conventional data transmission device, data 1 is modulated by a modulator 2 in a control station C, and sent to transmitting stations T1 to Tn, respectively, via wired lines 31 to 3n, for example.
to send at high speed.

In the transmitting stations T1 to Tn, demodulators 41 to 4n demodulate the modulated data received via lines 31 to 3n, registers 51 to 5n store the demodulated data, and clocks 61 to 6n register the data at a predetermined time. The transmitters 71 to 7n are configured to read the data stored in the antennas 41 to 4n and transmit the read data at low speed via the antennas 81 to 8n.

Therefore, the receiver 9 can receive data from each transmitting station Tl-Tn almost simultaneously, and can prevent soft errors.Problems to be Solved by the InventionHowever, the above conventional line delay amount In the correction device, the control station C must transmit data at high speed to the transmitting stations T1 to 'rn, and the clocks 61 to 6n of each transmitting station T1 to Tn must be accurately synchronized, so it is complicated and complicated. There is a problem that it is expensive.

Here, the accuracy of the clocks 61 to 6n must be set within an error corresponding to 1 bit error.
Must be set within the error.

SUMMARY OF THE INVENTION In view of the above conventional problems, it is an object of the present invention to provide a simple and inexpensive data transmission device.

Means for Solving the Problems In order to solve the above problems, the present invention provides means for transmitting signals to a plurality of transmitting stations via respective lines;
means for receiving a signal sent back from a transmitting station; means for calculating a delay time of the line based on the delay time of the transmitted and received signals; and a means for simultaneously transmitting data from the control station according to the delay time. Each transmitting station has a means for sending back a signal from the control station and a means for setting a data delay time such that the data is sent back from the control station at a delay time set by the control station. delay,
It was designed to be sent.

Effect: With the above configuration, the transmitting station simultaneously transmits data from the control station, and the receiver simultaneously transmits data from the transmitting station, depending on the delay time of the line connected to a plurality of transmitting stations. Furthermore, since there is no need to accurately adjust the clock of the transmitting station as in the conventional example, a simple and inexpensive data transmission device can be realized.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a data transmission device according to the present invention.

In FIG. 1, CO is a control station that transmits data, etc.
T 01 "" T On is a transmitting station that transmits data from the control station CO to the receiver 31 as a wireless signal.

In the control station Co, 11 oscillates a measurement signal for measuring the delay time of the line 15 connected to each of the transmission stations TOI to T□n, and uses the reception signal of this measurement signal to determine the delay time of the transmitted and received signal. 12 is a modulator that modulates the measurement signal from the measurement unit 11;
3 selectively switches the data 4 or the measurement modulation signal from the modulator 12 and sends the data to the transmitting stations To1 to T via the line 15.
□This is a switch that sends data to n.

Further, 17 is a demodulation unit that demodulates the measurement modulation signals transmitted from the transmitting stations TOI to TOn and outputs the demodulated signals to the measurement unit 11;
18 is a calculation unit that calculates the delay time of the line 16 as described later based on the delay time of the transmitted and received signals counted by the measurement unit 11; 19 is a calculation unit that calculates correction data according to the delay time calculated by the calculation unit 18; A control unit 20 that generates a transmission signal is a modulator that modulates the transmission signal from the control unit 19 and transmits it to each of the transmission stations To1 to T□n via a line 21; A keyboard that requires manual input of correction data according to the delay time.
23 are CB and T for displaying the delay time calculated by the calculation unit 18.

In each of the transmitting stations TOI to T (In, 23 is a demodulator that demodulates the data 4 or the measurement modulation signal transmitted from the control station Co via the line 15; 24 is the measurement demodulation signal from the demodulator 23 A modulator 25 modulates the signal and transmits it to the control station CO via the line 16.
a demodulator, 26, for demodulating the signal transmitted via 1;
The delay time of the line 15 connected to the control station CO is set, and the delay setting section 27 delays the data of the demodulator 23 by this delay time and outputs the data delayed by the delay setting section 26 to the antenna. It is a transmitter that transmits a wireless signal to a receiver 30 via 28.

Next, the operation of the embodiment according to the above configuration will be explained.

In FIG. 1, in the mode for setting the delay amount of the line 15 for each transmitting station TOI to TOn, the switch 13 is
It is switched to connect the modulator 12 and the line 15.

The measurement signal oscillated by the measurement unit 11 of the control station Co is transmitted to, for example, the transmitting station TOI via the modulator 12, switch 13, and line 15, and is controlled via the demodulator 23, modulator 24, and line 16. It is sent back to station Co.

In the control station Co, the measurement unit 11 counts the delay time t of this transmission/reception signal, and the transmission/reception of this measurement signal is performed over the line 15. This is performed a plurality of times (m) taking into account jitter, etc. of 16, and the delay time tm of each time is counted.

The calculation unit 18 calculates the delay time of one side line using the following calculation formula % Formula %, and the control unit 19 displays this delay time on the CRT 22.

When the operator inputs a correction value corresponding to the difference between the predetermined delay time tQ and this delay time via the keyboard 22, the control section 19 outputs this correction value data to the modulator 20, and this correction value data is , the modulator 20, the line 21, and the demodulator 25 to the delay setting unit 26.

Therefore, the control station Co transmits the measurement signal to each of the transmitting stations TOI to T□n via the line 15, counts the delay time of the line 15 based on the delay time of the transmitted and received signals, and calculates the correction data of the line 15. can be set in the delay setting section 26.

Next, in a mode in which data is transmitted to each of the transmitting stations To1 to TOn, the switch 13 of the control station CO is switched to connect the data 140 input side to the line 15.

In this case, data 14 is transmitted to each transmitting station To1-T□n via modulator 12, switch 13, and line 15, and demodulated by demodulator 23.

This demodulated data is delayed according to the correction data set in the delay setting section 26, and is transmitted to the receiver 30 via the transmitter 27 and antenna 28.

Therefore, according to the above embodiment, each transmitting station To1 to T
on is used to transmit the data after the predetermined delay time 1 (,) has passed after the control station Co transmits the data 14.
The receiver 30 can simultaneously receive data from each of the transmitting stations To1 to 'rOn, and can prevent errors caused by reception from multiple stations.

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention provides means for transmitting signals to a plurality of transmitting stations via respective lines, means for receiving signals sent back from the transmitting stations, and means for transmitting and receiving signals. A control station comprising means for calculating the delay time of the line based on the delay time, and means for setting the data delay time so that the transmitting station simultaneously transmits data from the control station according to the delay time. Each transmitting station has a means for sending back signals from the control station, and the data from the control station is delayed and transmitted by the delay time set by the control station, so transmission is not performed as in the conventional example. Since there is no need to accurately adjust the station clock, a simple and inexpensive data transmission device can be realized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a data transmission device according to the present invention, and FIG. 2 is a block diagram showing a conventional data transmission device. Co -- Control station, TOI~TOn... Transmission station, 11
...Measurement section, 12.20.24...Modulator, 15.1
6.21... Line, 17, 23.25... Demodulator, 18... Arithmetic unit, 19... Control unit, 26... Delay setting unit, 27... Transmitter, 3o... Receiving machine.

Claims (1)

[Claims] means for transmitting the signal to a plurality of transmitting stations via respective lines; means for receiving the signal sent back from the transmitting station; and means for calculating the delay time of the line from the delay time of the transmitted and received signals. and a control station having means for setting a data delay time so that the transmitting station simultaneously transmits data from the control station according to the delay time, and each of the transmitting stations What is claimed is: 1. A data transmission device comprising: means for sending back a signal; and data from a control station is delayed and transmitted by a delay time set by the control station.