JPS62135029A - Electric field strength monitor system - Google Patents

Abstract

PURPOSE:To monitor a reception electric field strength even near an indoor equipment by transmitting an identification signal designating a slave station to be monitored from the indoor equipment to an outdoor equipment and transmitting a level signal representing a reception electric field corresponding to the designated slave station from the outdoor equipment to the indoor equipment. CONSTITUTION:Terminals c1, c2 of a portable monitor 3 are connected to terminals b1, b2 of the indoor equipment 2. A multiplex circuit 23 inserts an identification signal 104 from the monitor 3 to an outgoing main signal 110 and outputs the result as an outgoing main signal 103. The outdoor equipment 1 uses a separation circuit 16 to separate the identification signal 104 from an outgoing main signal 103 and a changeover circuit 17 outputs the identification signal 104 selectively. Then a level signal 105 is converted by an A-D conversion circuit 14 and goes to a level signal 106. A multiplex circuit 15 inserts the level signal 106 to an incoming main signal 102 and outputs the result as an incoming main signal 107. The indoor equipment 2 uses a separation circuit 21 to separate the level signal 106 from the incoming master signal 107, a D-A conversion circuit 22 applies digital-analog conversion to form a level signal 105, which is inputted to a display section 32 of the monitor 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a field strength monitoring system, and more particularly to a field strength monitoring system at a master station in a time division multidirectional multiplex wireless communication system.

[Conventional technology]

A time division multidirectional multiplexing radio communication system is used as a subscriber radio system, etc. that accommodates a plurality of slave stations located around a master station.

Communication output signals input from outside the system for each slave station are interface-converted and time-division multiplexed in the indoor device of the master station to become a downlink main signal suitable for a wireless line. The downlink main signal is converted into a modulated wave at a master station transceiver installed outside the ring, such as on a steel tower, and is sent out. Each slave station transmits a communication signal to the outside of the system as a burst modulated wave at a timing assigned to the slave station.

The master station transceiver receives the modulated wave from each slave station, demodulates it, and converts it into an uplink main signal. The indoor device of the master station converts the upstream main signal into a communication output signal and outputs it to the outside of the system.

The master station constantly monitors the received field strength of modulated waves from each slave station for system maintenance.

That is, the level signal output by the master station transceiver in response to the received electric field strength (generally, wireless receivers have the function of outputting level signals) is sampled at the timing assigned to the modulated wave transmission of each slave station. The received electric field strength is monitored for each slave station.

[Problem that the invention seeks to solve]

In the conventional '1 electric field strength monitoring method, monitoring work could only be done near the master station transmitter/receiver, requiring work outdoors, which could be dangerous, especially if monitoring work was to be done in the event of a failure during bad weather. It also has the disadvantage of being accompanied by

SUMMARY OF THE INVENTION An object of the present invention is to provide a field strength monitoring system that solves the above-mentioned drawbacks and allows monitoring to be performed not only outdoors, where a master station transceiver is installed, but also at an indoor device installation location.

[Means for solving problems]

The field strength monitoring system of the present invention includes an interface unit that converts a communication input signal, which is a digital signal, through a transmission interface to suit a wireless transmission path and outputs it as a downlink main signal, converts an uplink main signal into a reception interface, and outputs it as a communication output signal. Then, the downlink main signal is converted into a modulated wave and sent to a plurality of slave stations, and the uplink modulated wave from the slave station is received and demodulated and output as the uplink main signal. In a field strength monitoring method of a master station of a time-division multidirectional multiplex wireless communication system in which a transmitter/receiver that outputs a level signal is installed separately, an identification signal is generated to arbitrarily designate the slave station to be monitored, a portable monitor device that inputs a second level signal representing the received electric field strength corresponding to the slave station and displays the level; a first multiplexing circuit that multiplexes the input identification signal into the downlink main signal; a bamboo separation circuit that is installed close to the transmitter/receiver and separates the identification signal from the downlink main signal; a switching circuit installed close to the transceiver and configured to select and output either one of the first separation circuit or the identification signal input from the monitor device; a level detection circuit that samples the first level signal at a timing corresponding to the identification signal inputted from the switching circuit and branches it into two to obtain two second level signals, one of which is output to the monitor device; a second multiplexing circuit installed close to the transceiver and multiplexing the second level signal, which is the other output of the level detection circuit, onto the main signal; and a second multiplexing circuit installed close to the interface section. and a second separation circuit that separates the second level signal from the previous two upstream main signals and outputs it to the monitor device.

[Implementation v! l) The present invention will be described in detail with reference to FIG. 8 showing the embodiment.

FIG. 1 is a block diagram showing one implementation of the field strength monitoring method of the present invention.

The embodiment shown in FIG.
4-41 people enter chi δ 109 and go down main signal 103
・Indoor device 2 that outputs a rail signal 105 and a communication output signal 108, and an indoor device 2 that outputs an identification signal 104 and a level signal 10.
Monitor device Jt3 that inputs 5 and uplink master No. 13 10
7 is transmitted from the outdoor device 1 to the indoor device 2.
and a down signal line 5 for transmitting the main signal 103 from the indoor device 2 to the outdoor device 1.

Outdoor decoration f! tl inputs the antenna 11, the master station transceiver 12 which is connected to the antenna 11 and outputs the level signal 101 and the upstream main signal 102, and inputs the downlink main signal 103, the output of the switching circuit 17 and the level signal 101, and outputs the level signal 101 and the main upstream signal 102. Level detection circuit 13 outputting signal 105 and level signal 10
5 and outputs the level signal 106; the multiplexing circuit 15 inputs the upstream main signal 102 and the level signal 106 and outputs the upstream main signal 107; Main signal 103/identification signal 104
The separation circuit 16 that outputs the separation circuit 16 or the terminal a
The switching circuit 17 inputs the identification signal 104 from the terminal 1. The level signal 105 is also output to the terminal a2.

The indoor device 2 inputs the upstream main signal 107 and outputs the upstream main signal 1.
07. A separation circuit 21 that outputs the level signal 106, a D-A conversion circuit 22 that inputs the level signal 106 and outputs the level signal 105 to the terminal b2, and the identification signal 104 and the downlink main signal 110 from the terminal bl. Input downlink main signal 10
3, and an interface section 24 that inputs an uplink main signal 107 and a communication input signal 109 and outputs a downlink main signal 110 and a communication output signal 108.

The monitor device 3 includes an identification signal generator 31 that outputs an identification signal 104 to a terminal C1, and a level signal 10 that outputs an identification signal 104 from a terminal C2.
5 and a display section 32 for inputting the information, and has a portable structure.

The WL2 diagram is an explanatory diagram showing the frame structure of the uplink main signals 102 and 107 and the downlink main signals 103 and 110.

These main signals are, as shown in FIG. 2, a common signal time slot (USG) and a subclaim (S!) for the communication terminal No. 48, which is used for communication with each slave station, respectively. ~ 斖l (n is the number of windows of T-stations).

First, the communication operation of the fruit canister U shown in FIG. 1 will be explained.

A plurality of communication input signals 109 inputted to the indoor device 2 from a switchboard etc. are transmitted to the downlink main signal 110 at the interface section 24.
The signal is converted into the downlink main signal 1 and input to the multiplexing circuit 23.
It becomes 03. The operation of the multiplexing circuit 23 is not related to the current operation. The downlink main signal 103 is input to the master station transceiver 12 via the downlink signal line 5 and the separation circuit 16 of the outdoor device 1, and is converted into a modulated wave and sent out from the antenna 11.

The modulated waves sent out by each slave station are input to the master station transceiver 12 via the antenna 11, and demodulated to become the upstream main signal 102. The upstream main signal 102 is input to the multiplexing circuit 15 and becomes the upstream main signal 107. The operation of the multiplexing circuit 15 is also not related to the communication operation. The upstream main signal 107 is sent to the interface section 2 via the upstream signal line 4 and the separation circuit 21 of the communication device 2.
4, the signals are converted into a plurality of communication output signals 108, and are output to a switchboard or the like.

Next, the electric field strength monitoring operation of the embodiment shown in FIG. 1 will be explained.

The identification signal generating section 31 of the monitor device 3 generates an identification signal 104 that is arbitrarily set and designates one of the slave stations.

When performing monitoring work near the outdoor device 1, the terminals C1 and C2 of the monitor device 3 are connected to the terminal al-a2 of the outdoor device 1. When this connection is made, the switching circuit 17
The input identification signal 104 is selected and outputted to the level detection circuit 13.

The master station transceiver 12 outputs a level signal 101 corresponding to the reception input level input from the antenna 11 (this level is proportional to the reception electric field strength). The level detection circuit 13 detects the slave station l specified by the home identification signal 104 of the communication signal subframe 5s=8n of the upstream main signal 102.
The level signal 101 is output as a sampling level signal 105 at the timing of the corresponding communication signal subframe.

The display unit 32 of the monitor device 3 receives the level signal 105 via the terminals a2 and C2 and displays the level. As a result, the received electric field strength corresponding to the slave station designated by the identification signal generating section 31 is displayed on the display section 32.

When performing monitoring work near the indoor device 2, the terminals C1 and C2 of the monitor device 3 are connected to the terminals b1 and b2 of the indoor device 2. The multiplexing circuit 23 converts the identification signal 104 input via the terminals C1 and bl into the common signal time slot group S of the main signal 110.

is inserted into an empty time slot and output as the downlink main signal 103.

The separation circuit 16 of the outdoor device 1 separates the identification signal 104 from the downlink main signal 103. The switching circuit 17 is connected to the outdoor device 1
If the terminals C1 and C2 of the monitor device 3 are not connected to the terminal al-a2, the separation circuit 16 outputs an identification signal 10.
Select and output 4.

On the other hand, the level signal 105 is converted from analog to digital by the A/D conversion circuit 14 and becomes a level signal 106. The multiplexing circuit 15 outputs the identification signal 1 in the downlink main signal 110.
The level signal 106 is inserted into the time slot of the uplink main signal 102 corresponding to the time slot used for inserting the signal 04 and outputted as the uplink main signal 107.

The separation circuit 21 of the indoor device 2 separates the level signal 106 from the upstream main signal 107. The level signal 106 is digital-to-analog converted by the D-A conversion circuit 22 to become the level signal 105, which is sent to the monitor device 3 via terminals b2 and C2.
input on the display section 32. As a result, in this case as well, the received electric field strength corresponding to the slave station specified in the identification signal generation g331 is displayed on the display section 32.

〔Effect of the invention〕

As explained in detail above, the field strength monitoring method of the present invention transmits an identification signal specifying a slave station to be monitored from an indoor device to an outdoor device, and also transmits a level indicating the received field strength corresponding to the designated slave station. Since signals can be transmitted from outdoor equipment to indoor equipment, it is possible to monitor the received field strength not only near outdoor equipment but also near indoor equipment, which has the effect of allowing monitoring work to be carried out safely and comfortably. Since the identification signal and level signal can be multiplexed and transmitted in vacant time slots of the downlink main signal and uplink main signal, the received signal strength can be monitored near indoor equipment without affecting communication operations. It is said to be effective and economical because the monitor device that generates the identification signal and displays the received field strength is portable and can be used for monitoring both outdoors and indoors. effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an actual sequence of the electric field strength monitoring system of the present invention, and FIG. 2 is an explanatory diagram showing the frame structure of various main signals in FIG. 1...Outdoor device, 2...Indoor device, 3
...Monitor device, 4...Uplink signal line,
5...Down signal line. Agent Patent Attorney Oto Uchihara Figure 2

Claims (1)

[Scope of Claims] An interface unit that converts a communication input signal, which is a digital signal, into a transmission interface to suit a wireless transmission path and outputs it as a downlink main signal, and converts the uplink main signal into a reception interface and outputs it as a communication output signal; converts the downlink main signal into a downlink modulated wave and sends it to a plurality of slave stations; receives and demodulates the uplink modulated wave from the slave station; outputs the uplink main signal as the uplink main signal; and outputs a first level signal representing the received electric field strength. In a field strength monitoring method for a master station in a time-division multidirectional multiplex wireless communication system in which an output transmitter/receiver is installed separately, an identification signal is generated that arbitrarily specifies the slave station to be monitored, and correspondence is applied to the slave station. a portable monitor device that inputs the level signal representing the received electric field strength and displays the level; a first multiplexing circuit that multiplexes the identification signal from the downlink main signal; a first separation circuit that is installed close to the transceiver and separates the identification signal from the downlink main signal; a switching circuit that selects and outputs either the first separation circuit or the identification signal input from the monitor device; and a switching circuit installed close to the transceiver and corresponding to the identification signal input from the switching circuit. a level detection circuit that samples the first level signal at a timing of 0 and branches the first level signal into two to obtain two second level signals, and outputs one of the second level signals to the monitor device; a second multiplexing circuit configured to multiplex the second level signal, which is the other output of the level detection circuit, onto the upstream main signal; and a second separation circuit that separates the second level signal and outputs it to the monitor device.