JPS6294032A - Delay correction system - Google Patents

Abstract

PURPOSE:To eliminate the need for a delay circuit exclusive for synchronization switching by setting the inserted delay time of a parity supervisory panel of an intermediate relay station of a system not sending a control signal equal to that of a branched insertion panel of a relay station sending the control signal. CONSTITUTION:A data input signal is subjected to code conversion by transmission code processing panels 11, 12 in a transmission terminal station 10, after an additional bit including a frame synchronizing pulse and a parity check pulse is inserted, the result is distributed to a transmission synchronizing switch 15 provided after the transmission code processing panel 4 of a standby radio system SP and each transmitter 13. In the intermediate repeater station 20, the branch insertion panel 23 branching and inserting the control signal and supervising the parity check pulse is inserted between a receiver 21 and a transmitter 22 in systems SP and SYS1 and the inserted delay times by the parity supervisory panel 24 not inserted with the control signal and the insertion panel 23 are made equal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a delay correction method, and particularly relates to a method for transmitting a control signal such as a meeting call signal or a supervisory control signal by inserting bits into the main signal in a digital wireless communication line. What is the transmission time difference between wireless systems that transmit control signals and other wireless systems that do not transmit control signals? This invention relates to a delay correction method for correction.

[Prior art] In digital wireless communication lines, meeting call signals,
Methods for transmitting control signal sounds such as supervisory control signals include an analog method in which 11 complex modulated sounds such as FM are added to the main signal, and a digital method in which bits are inserted into the main signal and transmitted. Analog systems have been widely used in the past due to their simple configuration and low cost, but from the perspective of effective use of frequency bands, recently developed multilevel quadrature amplitude modulation systems (such as 16-QAM or 64iQAM) have mainly A digital method is used.

The control signal described above is normally transmitted in parallel to the standby radio system and one working radio system, and is not transmitted to the other working radio system. In a wireless system that transmits all control signals, is this control signal sent to each intermediate relay station? A branch/insertion board is provided for branching and inserting.

This branch insertion board? Due to the insertion, a time delay of at least several bits occurs in the relayed data signal.

Therefore, when the number of intermediate relay stations increases, a considerable difference in transmission time occurs between a wireless system that transmits control signals and a wireless system that does not transmit all control signals. In digital wireless communication lines, in order to completely prevent line failures caused by VCs such as facing, a single switch with wireless disconnection is often adopted. In this case, the control signal? If there is a large transmission time difference between the standby wireless system that transmits and the working wireless system that does not transmit all of the transmission signals, synchronized switching will not be possible. A correction delay circuit is inserted into a wireless system that does not transmit data.

[Problems that the invention aims to solve] It is an object of the present invention to eliminate the above-mentioned problems and provide a delay correction scheme that does not require a dedicated delay path.

[problem? Means for Solving the Problem] The delay correction method of the present invention uses a digital wireless communication line consisting of a transmitting terminal station, an intermediate relay station, and a receiving terminal station to transmit control signals such as meeting call signals and monitoring notification control signals. In a delay correction method for correcting a difference in transmission time between a first wireless system that inserts bits into the main signal and transmits the control signal, and a second wireless system that does not transmit the control signal, 247') An insertion delay time of a drop-and-drop board installed at the intermediate relay station that performs drop-and-add of the control signal and monitoring 87 of parity check, re-pulse, and 247') installed at the intermediate relay station of the wireless system.・・・：11 tei・
The insertion delay time of the IJ tee for monitoring the check pulse is made equal to the insertion delay time of the IJ tee.

〔Example〕

Next, an embodiment of the present invention will be explained with reference to the drawings.

Figure 1 shows the line configuration of an embodiment of the present invention? This is a professional diagram showing only the -transmission direction for VC when there is one intermediate relay station. In FIG. 1, the backup radio system SP and the working radio system 5YSI are a first radio system that inserts bits into the main signal and transmits the control signal;
The active wireless systems 5Y82 to 5YSn are the second wireless systems that do not transmit control signals, and transmit terminal stations 10.
Intermediate relay station 20. Each receiving terminal station 30 has the following two configurations.

In the transmitting terminal station 10, the data input signal, which is normally transmitted at 5YSx to 5YSn, is converted from bipolar code to unipolar code by the transmitting code processing board 11, 12, and a frame synchronization pulse, a check pulse during parity, etc. After the additional bits containing are inserted, a transmission 1x synchronization switch 15 is installed after each transmitter 13 and the transmission code processing board 14 of the SP.
It is distributed to n.

SP and 5YSIT transmission; n-le allocation signal 101 digits divided into 3;
1/ic, the other bits are sent to the signal insertion board 16 provided after the transmission synchronization switch 15, and the 1/ic bit is inserted into the main signal. It is configured to be inserted.

In the intermediate relay station 20, the receiving device 21 is connected to the SP and 5YSI that transmit the control signals of each wireless system.
A branch/insertion board 23 is inserted between the control signal ft22 and the control signal ft22 for branching/inserting the control signal and monitoring and correcting the section parity check pulse. No transmission 5
For YS2 to 5Y8n, is there only parity check pulse monitoring and correction for the section? A parity monitoring board 24 is inserted to perform the parity monitoring. And the branch/insertion board 23 and the parity monitoring board 24? Delay in main signal transmission time due to insertion (
(insertion delay time) are configured so that both are equal. Note that the functional arrangement, signal cable length, and waveguide length of each wireless system are usually set so that the transmission time of each wireless system is approximately equal.

In the receiving terminal station 30, among the signals received (W demodulated and spread) by each receiving device 31, the signals of 5YSI to 5YSn are sent to the reception code processing board 33, 34 via the reception fE=1 period switch 32?
Next, the SP signal is applied to the reception code processing board 33 via the reception distribution board 35, where it undergoes the reverse code processing as in the transmission code processing board. 5Y at the reception distribution board 35 to the SP signal
Each receiving cycle switcher 32VC of SI to 5YSn is distributed, and the receiving synchronization switcher 32 synchronizes the signals sent in parallel from the transmitting terminal station to the working and backup signals, and eliminates frame synchronization that occurs due to fading. After adjusting the phase difference between the pulses, the system is configured to perform synchronous switching without momentary interruption. Note that the received code processing board 33 extracts control signals.

In recent digital wireless communication lines that lend large amounts of communication money, what is the transmission quality between the transmitting and receiving end stations? Monitor and switch to backup radio system Parity/parity for system switching for full control
Besides check pulse.

In order to monitor the transmission quality of each wireless relay section and easily identify defective relay sections, a method is used in which all section parity check pulses are set, and each intermediate relay station detects and monitors the noise. Ru. The ninth point for this purpose is that the insertion delay time of the parity monitoring board 24 inserted into each intermediate relay station is the same as the insertion delay time of the drop-and-add board 23, which performs drop-insertion of control signals and parity monitoring as described above. (If you set
It is possible to eliminate the transmission time difference between the first wireless system and the second wireless system. Therefore, at the receiving terminal,
Control signal? SP and control signal to be transmitted? No transmission 5
Between YS2 and 5YSn, it is necessary to install a dedicated delay circuit with gold film to correct the transmission time difference, except for dynamic fluctuations in the 7-age period (this can be adjusted with the reception synchronization switch). do not have. Note that the configurations of the transmitting terminal station and receiving terminal station are the same as those of the prior art.

〔Effect of the invention〕

To address the errors described in detail above, the delay correction method of the present invention
: fL, the branch/additional board inserted into the wireless system that transmits the control signal at each intermediate relay station, and the control signal? Since the insertion delay time of each parity monitoring board inserted into a wireless system that does not transmit data is the same, a dedicated delay circuit for shaft clamping is required regardless of the number of intermediate relay stations. ? Synchronous switching without using it? This has the effect of allowing all digital wireless communication lines to be configured.

[Brief explanation of drawings]

Figure 1 shows the line configuration of an embodiment of the present invention? FIG. 10... Transmitting terminal station, 11.12.14...
...Transmission code processing board, 13.22...Transmission device, 15...Transmission synchronization switch, 16...
Signal insertion board, 20...Intermediate relay station, 21.31
...Receiving device, 23... Branch/insertion board, 2
4... Parity monitoring board, 30... Receiving terminal station, 32... Receiving synchronization switch, 33. 34
...Reception code processing board, 35...Reception distribution board.

Claims (1)

[Claims] A digital wireless communication line consisting of a transmitting terminal station, an intermediate relay station, and a receiving terminal station, which transmits control signals such as meeting call signals and supervisory control signals by inserting bits into the main signal.
In the delay correction method for correcting the difference in transmission time between a wireless system and a second wireless system that does not transmit the control signal, the control signal is branched at the intermediate relay station of the first wireless system. an insertion delay time of a branch/insertion board that performs insertion and monitors parity check pulses;
A delay correction method characterized in that the insertion delay time of a parity monitoring board provided at the intermediate relay station of the second radio system and monitoring parity check pulses is set to be equal to the insertion delay time.