JPH06164561A - Digital radio communication switching device - Google Patents

Abstract

PURPOSE:To switch/control a line for always realizing radio transmission in the best state by detecting the quality of N-number of raio communication lines, selecting M-number of lines whose qualities are satisfactory and switching/ connecting the lines to a transmission line. CONSTITUTION:Erroneous pulse detection circuits 611-6N1 are provided in respective receivers 61-6N. Erroneous pulses 201-2ON are outputted when an error in respective reception signals is detected. An erroneous pulse comparison circuit 91 in a switching controller 9 compares the generated number of the pulses 201-20N, and outputs quality order signals 911-91N in the order of the generation frequency of the erroneous pulses in the respective radio lines. A switching judgement circuit 92 selects the M-number of lines whose qualities are satisfactory among the N-number of radio lines based on signals 911-91N, and outputs information on the M-number of lines as line allocation information 921. A switching control circuit 93 outputs switching control signals 901 and 902 for switching the lines in a transmission switch and a reception switch in accordance with information 921.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital radio communication switching apparatus having a backup line for improving line quality in a digital radio transmission system and configured to switch lines when the line quality deteriorates.

[0002]

2. Description of the Related Art Generally, a line switching device having a structure shown in FIG. 3 has been proposed in a digital radio transmission system having a redundant line. In the figure, N transmitters 21 are provided for M digital transmission signal paths 11 to 1M.
.About.2N (N> M) are arranged, and the digital transmission signal paths 11 to 1M are selectively switched to and connected to the transmitters 21 to 2N by the transmission switch 3 having a matrix structure. Each of the transmitters 21 to 2N is connected to the transmitting antenna 4 and wirelessly transmitted. On the other hand, on the receiving side, N receivers 61 to 6N corresponding to the transmitters 21 to 2N are provided.
Are connected to the receiving antenna 5, and M number of digital transmission signal paths 8 are provided by the receiving switch 7 having a matrix configuration.
1-8M are selectively connected to output received signals to these digital transmission signal paths 81-8M, respectively. Then, a switching controller 9 is connected to each of the receivers 61 to 6N, outputs switching control signals 901 and 902 based on a switching determination signal output from each of the receivers 61 to 6N, and transmits to the transmission switch 3. The receiving switch 7 is configured to switch correspondingly.

FIG. 4 is a block diagram showing the relationship between the receivers 61 to 6N and the switching controller 9 in the conventional digital radio transmission system. Each of the receivers 61 to 6N has an error rate judging circuit 612 to 6N2. It is provided. These error rate determination circuits 612 to 6N2 detect the error rate of a signal received by each receiver, determine that the error is a line failure when the error rate exceeds a certain value, and are below a certain value. It is possible to determine that the line has been restored and output the determination results as the above-described switching determination signals 211 to 21N.

Further, the switching controller 9 has switching determination signals 211 to 21 from the error rate determination circuits 612 to 6N2.
After inputting N and comparing these switching determination signals 211 to 21N as a whole, the switching control signal is based on a predetermined algorithm, for example, an algorithm for prioritizing the switching determination signal of the starter and switching the line. A switching control circuit 94 that outputs 901 and 902 is provided. In response to the switching control signals 901 and 902 from the switching control circuit 94, in the transmission switch 3 and the reception switch 7, the digital transmission signal paths 11 to 1M are respectively set to the transmitter and the receiver of the line determined to have the line fault. , 81 to 8M, and switched and connected to a transmitter and a receiver of a spare line that has not been used until then, and a better wireless connection can be secured.

[0005]

In such a conventional radio communication switching device, particularly when switching the lines in the switching controller 9, the error rate judging circuits 612 to 612 provided in the receivers 61 to 6N of the respective lines. Since the line failure is judged based on the error rate obtained from 6N2, if the line failure occurs on two or more lines at the same time, the line failure is detected regardless of the line failure level, that is, the line quality. The line that has been determined to have a line failure is given priority for switching. Therefore, even if the quality deterioration of the line where the line failure occurs first is small and the quality deterioration of the line where the line failure occurs later is significant, the side where the line failure occurs first is relieved with priority. As a result, there is a problem that the line failure on the side where the quality deterioration is remarkable cannot be relieved.

Further, when the error rate in each receiver is smaller than a certain fixed value, switching is not performed, so that the line quality of the line not currently used as a protection line is the same as that of the line currently used. Even if the line quality is better, the line is not switched, and as a result, the good line is unnecessarily idle, and there is a problem that the transmission quality of the entire digital wireless transmission system cannot be improved. It is an object of the present invention to provide a digital wireless communication switching device capable of switching control of a line for always realizing wireless transmission in the best state.

[0007]

The present invention has M digital signal transmission lines and N wireless communication lines more than M digital signal transmission lines, and M wireless communication lines out of N wireless communication lines. In a digital wireless communication switching device for switching and connecting a line to the M digital signal transmission lines, the line quality of N wireless communication lines is detected, and M lines with good line quality are selected from these. And a means for switching and connecting these to a digital signal transmission path. That is, means for generating each error pulse in the N wireless communication lines,
A means for counting the number of generated error pulses of each wireless communication line and comparing the line qualities of all the lines and ordering the line qualities, and from the ordered lines having good line quality It is provided with means for selecting a line and assigning a digital signal transmission line to the selected line, and means for switching and connecting the digital signal transmission line and the wireless communication line based on this assignment. For example, a transmission switch for switching and connecting M digital signals on the transmission side to M of N transmitters, and M digital signals on the reception side to M of N receivers. A receiving switch for switching and connecting transmission lines, an error pulse generating circuit provided in each of the N receivers, and a line quality of each of the N receivers is detected based on outputs of the error pulse generating circuits. , A switching controller for selecting and connecting M lines of good line quality to the digital signal transmission line, and the switching controller is provided in an error pulse generation circuit output from each receiver. An error pulse number comparison circuit that counts the number of error pulses in each receiver based on this and compares the respective error pulse numbers and outputs a quality rank signal, and M number of good quality signals based on this quality rank signal. Receiver A switching determination circuit that outputs allocation information to select the line, configuration to and a switching control circuit for outputting a switching control signal for controlling the switching operation of the receiving switch as the switch described above on the basis of the assignment information.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of the essential parts of the present invention.
An example in which the present invention is applied to the digital wireless transmission system shown in FIG. That is, as shown in FIG. 3, the M digital signal transmission lines 11 to 1M are switched to N transmitters 21 to 2N (N> M) by the transmission switch 3, and each transmitter 21 to 2N is A signal is transmitted from each transmitting antenna 4. Further, on the receiving side, the signals from the respective transmitters 21 to 2N are transmitted through the receiving antenna 5 to the N receivers 31 to 3N.
And the received signal is received by the receiving switch 3
The digital signal transmission lines 81 to 8M are switched and connected. Then, switching of each line between the transmission switch 3 and the reception switch 7 is performed by switching control signals 901 and 902 output from the switching controller 9. Therefore, of the wireless lines formed by the N transmitters 21 to 2N and the receivers 61 to 6N, M wireless lines connected to the digital signal transmission line are working lines and are not used (N -M) The number of lines is set as the protection line.

The switching controller 9 and N receivers 61 to 6
As for the relationship of N, as shown in FIG. 1, each of the receivers 61 to 6N is provided with an error pulse detection circuit 611 to 6N1, and an error in a signal received by each of the receivers 61 to 6N is detected. Error pulses 201 to 20N can sometimes be output. Further, the switching controller 9 is provided with an error pulse comparison circuit 91 to which the outputs of the error pulse detection circuits 611 to 6N1 of the receivers 61 to 6N are input, and the error pulse detection circuits 611 to 6N1. The number of error pulses 201 to 20N output from each is compared, and the quality rank signals 911 to 911
91N is output.

A switching judgment circuit 92 is connected to the error pulse comparison circuit 91, and an input quality ranking signal 9 is inputted.
Based on 11 to 91N, M lines with good line quality are selected from N wireless lines, and information of these M lines is output as line allocation information 921. A switching control circuit 93 is connected to the switching determination circuit 92, and switching control signals 901 and 902 for executing the line switching of the transmission switch 3 and the reception switch 7 according to the input line allocation information 921 are transmitted. Output.

The operation of the digital wireless communication switching device having this configuration will be described with reference to the flowchart of FIG.
Depending on the operation of the digital radio transmission system, N receivers 6
1 to 6N receive the signals of the corresponding transmitters 21 to 2N to generate error pulses 201 to 20N corresponding to the error in the received signal from the error pulse detection circuits 611 to 6N1 respectively provided, This error pulse 201
.About.20N are input to the error pulse comparison circuit 91 (step S10). Then, the error pulse comparison circuit 9
In No. 1, the number of error pulses in each of the N wireless lines during a fixed time is counted and stored in the memory (step S11). Next, the stored error pulse numbers are compared with each other, and the line with the smallest number of error pulses, the line with the next smallest number of error pulses, and the largest line are sequentially detected. Then, the lines are ordered in ascending order of the number of error pulses, and this is output as quality ranking signals 911 to 91N (step S12).

Next, the switching determination circuit 92 selects the upper M lines with good line quality from the quality ranking signals 911 to 91N and outputs them to the switching control circuit 93 as the line allocation information 921 (step). S13). In the switching control circuit 93, M digital signal transmission lines 11 to 1M, 81 are selected for the selected M lines with good line quality.
.About.8M are sequentially allocated, and the switching control signals 901 and 902 for executing this allocation are respectively transmitted to the transmission switch 3
Is output to the receiving switch 7 (step S15). In these switches 3 and 7, the switching control signals 901 and 9
02, the switching connection between the digital signal transmission lines 11 to 1M and the transmitters 21 to 21N, and the receivers 61 to 6
Switching connection between N and the digital signal transmission lines 81 to 8M is executed (step S16).

If the transmission has already been performed and continued, after the determination (step S14), for example,
The switching control circuit 9 determines whether or not the M wireless lines assigned with good line quality are currently used (step S17), and no signal is output when this line is used. However, if it is not used, control is performed so that a digital signal transmission line using a currently unassigned wireless line is assigned to this vacant wireless line (step S18) to switch the switch. May be.

As a result, the line quality at each time is judged in a constant time unit for counting the number of error pulses, and among the N lines, M lines having good line quality are judged based on the judged line quality. It is possible to perform wireless communication with this line being switched and connected to the digital signal transmission line. As a result, it is possible to always perform wireless communication with the best line quality, and it is possible to avoid waste that a wireless line with good line quality may not be used.

[0015]

As described above, the present invention provides a digital wireless communication switching device configured to switch and connect M wireless communication lines of N wireless communication lines to a digital signal transmission line. Since it is equipped with means for detecting the line quality of the wireless communication line, selecting M lines with good line quality, and switching and connecting these to the digital signal transmission line, always use the line with the high line quality. That is, it is possible to avoid the waste that the communication is secured and the line with good line quality is not used, and it is possible to improve the transmission quality of the entire digital wireless transmission system. In addition, after counting the error pulses in the N wireless communication lines, the line qualities of all the lines are compared, the line qualities are sequenced, and the M lines are selected from the ones with good line qualities. Since the lines are switched and connected so that a digital signal transmission path is assigned to the selected line, wireless communication can always be performed in real time using a line with good line quality with a small number of error pulses. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a main part of a digital wireless communication switching device of the present invention.

FIG. 2 is a flowchart for explaining an operation of switching a line.

FIG. 3 is a block diagram showing an overall configuration of a digital wireless communication switching device to which the present invention is applied.

FIG. 4 is a block diagram of a part of a conventional digital wireless communication switching device.

[Explanation of symbols]

 11-1M Digital signal transmission line (transmission side) 21-2N Transmitter 3 Transmission switch 61-6N Receiver 7 Reception switch 81-8M Digital signal transmission line (reception side) 9 Switching controller 91 Comparison circuit 92 Switching determination circuit 93 Switching control circuit 611 to 6N1 error pulse detection circuit

Claims (3)

[Claims] 1. A digital signal transmission line having M lines and N wireless communication lines, the number of which is larger than that of the digital signal transmission lines, and M wireless communication lines of the N wireless communication lines are connected to the M digital signals. In a digital wireless communication switching device switchingly connected to a transmission line, the line qualities of the N wireless communication lines are detected, and M lines having a good line quality are selected from these lines to be connected to the digital signal transmission line. A digital wireless communication switching device comprising means for switching connection. 2. A means for generating error pulses in each of N wireless communication lines and the number of error pulses generated in each wireless communication line is counted to compare the line quality of all lines, and the line quality is compared. And a means for allocating digital signal transmission paths to the selected lines, and a digital signal transmission based on this allocation. 2. The digital wireless communication switching device according to claim 1, further comprising means for controlling switching and connection between the communication path and the wireless communication line. 3. A transmission switch for switching and connecting the digital signal transmission lines of M transmission sides to M of N transmitters, and M reception sides of M of N receivers. A receiving switch for switching and connecting the digital signal transmission line of
Error pulse generating circuits provided in the respective receivers, and the line quality of each of the N receivers is detected based on the outputs of the error pulse generating circuits, and M lines with good line quality are selected. Then, a switching controller for switching connection to the digital signal transmission path is provided, and the switching controller counts the number of error pulses in each receiver based on the error pulse generation circuit output from each receiver, And an error pulse number comparison circuit for comparing the respective error pulse numbers and outputting a quality rank signal, and a switch for outputting allocation information selecting a line of M receivers of good quality based on the quality rank signal. A digital radio, comprising: a determination circuit; and a switching control circuit that outputs a switching control signal that controls switching operation of the transmission switch and the reception switch based on the allocation information. Shin switching device.