JPH06132861A - Radio repeater - Google Patents

Abstract

PURPOSE:To provide a radio repeater which can stably repeat radio waves with instable received field intensity. CONSTITUTION:While an arrival of radio waves to request radio repetition is waited, a control part 5 inputs a judged output of a first received field intensity judge circuit 8 by using a judge switching circuit 10, when the received field intensity is higher than a first level, the repetition is started, the judged output of a second received field intensity judge circuit 9 is switched and inputted, the received field intensity is checked at a second level, round-off processing is performed to the received input lower than the second level, and received contents are not transmitted. The second level is lower than the first level. The radio waves lower than the first level under waiting is not repeated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the stability of relay connection operation of a wireless repeater having a wireless receiver, a wireless transmitter and a controller.

[0002]

2. Description of the Related Art In recent years, wireless repeaters have been widely used and have contributed to convenience and securing a wide communication area.

A conventional radio repeater will be described below with reference to the drawings. FIG. 3 is a block diagram showing the configuration of a conventional wireless repeater. In the figure, 1 is an antenna, 2 is an antenna duplexer for sharing the antenna 1 for transmission and reception, 3 is a transmitter, 4 is a receiver, 5 is a control unit for controlling the operation of the entire wireless repeater, 6 Is a power supply, and 11 is a noise squelch detection circuit.

FIG. 4 is a schematic diagram showing a communication state between mobile stations. Mobile station 13 (hereinafter referred to as "a station") and mobile station 14
In the case where the mobile station and the mobile station can be directly communicated with each other (hereinafter, referred to as “b station”), communication can be performed by alternately repeating transmission and reception with the radio wave having the frequency fd. However, when the mobile stations are far from each other and communication cannot be performed directly or when it is extremely difficult, communication is performed via the wireless repeater 12 of the relay station. In this case, station a issues a relay connection request signal for requesting relay connection to the relay station. The radio wave for the relay connection request is the direct communication frequency fd.
Different from the above, a radio wave having a shift frequency fr lower or higher by fs is used. When the relay connection request signal is superposed on the transmission signal such as voice from the station a and a transmission call is made, the wireless repeater 12 of the standby relay station passes through the antenna 1 and the antenna duplexer 2 shown in FIG. After receiving the radio wave of the frequency fr by the control unit 5 and determining that the control unit 5 is the relay request signal, the transmission signal such as the voice received by the receiver 4 is transmitted by the transmitter 3.
Then, the transmission is started with the radio wave having the transmission frequency fd. The station b receives the radio wave of the frequency fd and receives the transmission signal of the station a. Note that the transmission from the b station to the a station can be performed in the same manner. In this way, long-distance communication between station a and station b is possible via the wireless repeater of the relay station.

In a wireless repeater, when the radio waves of a large number of mobile stations and other base stations are relayed and a relay connection request is processed in the presence of interference, etc., the electric field strength is extremely weak and the movement is unstable. Relay connection from the station is difficult. The noise squelch detection circuit 11 of the wireless repeater is used for the purpose of eliminating the relay connection request of the mobile station having such a weak and unstable electric field strength.

FIG. 5 shows the time-dependent characteristics of the received electric field strength and the transmission state of the wireless repeater. Level 1 and level 2 in FIG. 5A are levels at which the noise squelch detection circuit 11 shown in FIG. 3 refers to the received electric field strength, and the received electric waves below the level are cut off to control only the electric wave with less noise. This is a level for the section 5 to select, and is called a squelch level. FIG. 5B shows a transmission state corresponding to the squelch operation. In FIG. 5A, in the periods (1) to (8), the received electric field strength changes above and below the squelch level of level 1, and the periods (2) to (3), the periods (4) to (5), and the periods In (7) to (8), the electric field strength is higher than the squelch level, but the electric field strength is lower than the squelch level in other periods, and the signal-to-noise ratio is small in that period, which is preferable reception. Not in a state. The purpose of noise squelch is not to relay the received contents of such weak electric field strength. However, generally, when the transmission voltage falls below the squelch level, the transmission is not immediately cut off, but the transmission is continued for a predetermined period, for example, 5 seconds. Therefore, as shown in FIG. 5B, the transmission is continued in the periods (3) to (4), but the period (5) to
As in the case of (7), the period (5)-
(6) continues the transmission, and the period (6)-
In (7), the transmission is terminated. Period (9)-(1
The same applies to 4). In this period, the squelch level is set to level 2, which is higher than level 1, so the period to be truncated is increased.

[0007]

In such a conventional wireless repeater, as shown in FIG. 5, when the electric field strength of the reception fluctuates and falls below the squelch level, the communication voice or signal is interrupted, Or, there is a problem that the relay connection is disconnected.

The present invention solves the above problems, and an object of the present invention is to provide a wireless repeater capable of stable relay connection.

[0009]

In order to achieve the above object, the present invention inputs a radio receiving means for receiving radio waves, a radio transmitting means for transmitting radio waves, and a reception output of the radio receiving means. First reception field strength determination means for determining whether the reception field strength is equal to or higher than a first level, and a second level smaller than the first level are set, and the reception field strength is equal to or higher than the second level. Second receiving electric field strength judging means for judging whether or not the judgment output is made by switching between the judgment output of the first receiving electric field strength judging means and the judgment output of the second receiving electric field strength judging means. And a control unit for controlling the relay operation, wherein the control unit is configured to perform the first switching by the determination switching unit while waiting for arrival of the relay request radio wave.
When the received electric field strength does not reach the first level, no relay is performed. When the received electric field strength is equal to or higher than the first level, the relay of the radio wave is started. The judgment switching means switches and inputs the judgment output of the second received electric field strength judgment means, and relays when the received electric field strength is equal to or higher than the second level during relaying,
It is a wireless repeater that controls so as to perform a predetermined truncation process on a received input that does not reach the second level.

[0010]

According to the present invention, in the above-mentioned structure, when the wireless repeater waits for the relay connection request signal, the received electric field strength is judged by the first received electric field strength judging means, and for the electric wave of the first level or higher. When the relay is started, the second received electric field strength determination means checks the received electric field strength at the second level lower than the first level, and when the electric field strength lower than the second level is input, a predetermined truncation process is executed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A radio repeater according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a wireless repeater according to an embodiment of the present invention. The same components as those of the conventional example shown in FIG. The present invention is different from the conventional example in that the control input unit 7 that specifies the control operation of the control unit 5, the first reception electric field strength determination circuit 8 that determines whether or not the electric field strength of the relay request radio wave is sufficient, A second received field strength determination circuit 9, which determines the field strength of
The control operation of the control unit 5 includes a determination switching circuit 10 for switching the determination outputs of the first and second reception electric field strength determination circuits 8 and 9 according to an instruction from the control unit 5. Also,
FIG. 2 shows the electric field strength of the received radio wave and the corresponding transmission state in the wireless repeater according to one embodiment of the present invention as a time-lapse characteristic.

The mutual relationship and operation of the above components will be described. The control unit 5 inputs the judgment output of the first received electric field strength judgment circuit 8 by the judgment switching circuit 10 in the state of waiting for the radio wave requesting the relay. The incoming radio wave is received by the receiver 4 via the antenna 1 and the antenna duplexer 2, and the first received electric field strength judgment circuit 8 judges whether the received electric field strength is sufficient for relaying. When the received electric field strength is sufficient for relaying, the control unit 5 starts the relaying, switches the input to the judgment output of the second received electric field strength judgment circuit 9 by the judgment switching circuit 10, and inputs it. And relay it while performing the truncation process. If it is determined that the determination output of the first received electric field strength determination circuit 8 is not sufficient for relaying, relay is not performed.

FIG. 2 shows the electric field strength of the received radio wave and the corresponding transmission state in the wireless repeater according to one embodiment of the present invention as a time-lapse characteristic. In FIG. 2, the first level is the first
The reception electric field strength determination circuit 8 is a level for judging the reception electric field strength, and the second level is a level for the second reception electric field strength judgment circuit 9 to judge the electric field strength of the received radio wave. This second level is set to a level lower than the first level.
In the radio wave standby state, the first reception electric field strength determination circuit 8 determines the reception electric field strength at the first level, and the control unit 5
Relaying is started for radio waves of the first level or higher, and during the relaying, the second received electric field strength determination circuit 9 checks the electric field strength at the second level. When the electric field strength does not exceed the second level, the truncation operation is performed as in the conventional example.

In FIG. 2A, the radio repeater receives the radio wave of the station a at the time (1) during standby, and the control unit 5 inputs the judgment result of the first received electric field strength judgment circuit 8. Since the received electric field strength is equal to or higher than the first level, the control unit 5 instructs the relay and the received contents are sent from the transmitter 3. After the start of relaying, the control unit 5 switches to the judgment output of the second reception electric field strength judgment circuit 9 by the judgment switching circuit 10 and inputs the judgment output to check the reception electric field strength. During the periods (1) and (2), the received electric field strength is always the second level or higher, the relay is completed at the time (2) without performing the truncation processing of the transmission output, and the determination switching circuit 10 sets the first The reception electric field strength determination circuit 8 is switched to the standby mode. B at time (3)
Although the radio wave of the station arrives, the received electric field strength is below the first level in the periods (3) to (4), and the control unit 5 does not instruct the relay. Also, at time (5), the radio wave of station c arrives, and at time (6), the level becomes equal to or higher than the first level. Therefore, relaying is started, and the reception electric field strength check at the second level is started. In the period (5) to (15) after the start of relay,
The received electric field strength may also be lower than the second level, and the transmission is not interrupted because it is within the predetermined time in the periods (7) to (8) and the periods (10) to (11), but the period (1
In 2) to (14), since it is the predetermined time or more,
In 3), the transmission is cut off, the standby mode is entered, and the first received electric field strength determination circuit 8 checks the first level.
Therefore, the received contents in the periods (13) to (15) are not transmitted. However, the period below the first level (10)
Most of (15) to (15) are relayed without being truncated as in a conventional wireless relay device.

As described above, according to the wireless repeater of the embodiment of the present invention, the first reception electric field strength judgment circuit for judging whether or not the reception electric field strength is equal to or higher than the first level sufficient for relaying, A second received field strength judgment circuit for judging whether the received electric field strength during relaying is equal to or higher than a second level smaller than the first level, a judgment output of the first received field strength judgment circuit, and the second. A judgment switching circuit for switching and outputting the judgment output of the reception electric field strength judgment circuit is provided, and the judgment output of the first reception electric field strength judgment circuit is switched and inputted by the judgment switching circuit during reception standby. After the relay is judged according to the level and the relay is started at the first level or higher, the judgment output of the second received electric field strength judgment circuit is switched and input to handle the received electric field strength lower than the second level. Only the specified rounding down By operating, it relays the received radio field intensity varies at the first level adjacent stable.

A fixed level may be set as the second level, or any one of a plurality of different levels may be selectively set. As the second level is set lower, radio waves having a smaller signal-to-noise ratio will be relayed without interruption. Therefore, it is preferable to set the second level according to the importance of the relay request. For that purpose, the reception request signal itself may be provided with a signal for setting the second level, and the control unit may be configured to set the second level according to the signal. The second level can also be set by wire control from an external control center or the like. By such selection setting of the second level, it is possible to make a more detailed reception field strength determination. The control input section 7 in FIG. 1 is provided as means for inputting the external wired control signal to the control section 5.

It is needless to say that the noise squelch detection circuit in the conventional example may be used as the first received electric field strength determination circuit 8.

[0019]

As is apparent from the above embodiments, the present invention inputs and receives radio receiving means for receiving radio waves, radio transmitting means for transmitting radio waves, and reception output of the radio receiving means. A first received electric field strength determination means for determining whether the electric field strength is equal to or higher than a first level, and a second level smaller than the first level are set, and the received electric field strength is second.
Second reception electric field strength judgment means for judging whether or not the level is higher than or equal to the level, judgment output of the first reception electric field strength judgment means and judgment output of the second reception electric field strength judgment means are switched and output. Determination switching means and a control means for controlling the relay operation, wherein the control means inputs the determination output of the first received electric field strength determination means by the determination switching means while waiting for arrival of the relay request radio wave, When the received electric field strength does not reach the first level, the relay is not performed. When the received electric field strength is equal to or higher than the first level, the relay of the radio wave is started and the judgment switching means causes the second received electric field strength judgment means to operate. The judgment output is switched and input, relaying is performed when the received electric field strength is equal to or higher than the second level during relaying, and control is performed to perform a predetermined truncation process on the receiving input that does not reach the second level. By the relay machine, a weak,
Moreover, interruption of transmission voice and interruption of the relay connection state are reduced during relaying when a relay connection request from an unstable wireless station is received, and smooth wireless communication with good call quality can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a wireless repeater according to an embodiment of the present invention.

FIG. 2 is a graph showing changes with time of a received electric field strength and a corresponding transmission state in a wireless relay device according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a conventional wireless repeater.

FIG. 4 is a schematic diagram showing a state of wireless relay.

FIG. 5 is a graph showing a change over time of a received electric field strength and a corresponding transmission state in a conventional wireless repeater.

[Explanation of symbols]

1 antenna (radio receiving means and radio transmitting means) 2 antenna duplexer (radio receiving means and radio transmitting means) 3 transmitter (radio transmitting means) 4 receiver (radio receiving means) 5 control section (control means) 8 1st Receiving electric field strength judging circuit (first receiving electric field strength judging means) 9 Second receiving electric field strength judging circuit (second receiving electric field strength judging means) 10 Judgment switching circuit (judgment switching means)

Claims (3)

[Claims] 1. A radio receiving means for receiving radio waves, a radio transmitting means for transmitting radio waves, and a reception output of the radio receiving means are inputted, and it is judged whether or not the reception electric field strength is equal to or higher than a first level. First reception field strength determination means, and second reception field strength determination means that is set to a second level smaller than the first level and determines whether the reception field strength is equal to or higher than the second level. The control means includes a determination switching means for switching and outputting the determination output of the first received field strength determination means and the determination output of the second received field strength determination means, and control means for controlling the relay operation. Means for determining whether or not the first signal is output by the determination switching means while waiting for the arrival of the relay request radio wave.
When the received electric field strength does not reach the first level, no relay is performed. When the received electric field strength is equal to or higher than the first level, the relay of the radio wave is started. The judgment switching means switches and inputs the judgment output of the second received electric field strength judgment means, and relays when the received electric field strength is equal to or higher than the second level during relaying,
A wireless repeater that controls so as to perform a predetermined truncation process on a received input that does not reach the second level. 2. The wireless repeater according to claim 1, wherein the control means sets the second level by a level setting signal carried by the relay request radio wave while waiting for the arrival of the relay request radio wave. 3. The wireless repeater according to claim 1, wherein the control means sets the second level by a wired control signal from the outside while waiting for arrival of the relay request radio wave.