JP3717599B2 - Wireless repeater amplifier - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio relay amplification apparatus used in a mobile communication system such as a mobile phone.
[0002]
[Prior art]
2. Description of the Related Art In recent years, in mobile communication systems such as mobile phones, services using wireless relay amplification devices are becoming widespread as countermeasures for dead zones such as tunnels and underground malls where radio waves from base stations do not reach.
[0003]
FIG. 1 is a diagram showing a configuration example of a wireless relay amplification system to which the present invention is applied.
The downlink radio wave transmitted from the base station transmission / reception antenna 2 of the base station 1 is received by the base station antenna 4 of the radio relay amplification device 3, amplified by the radio relay amplification device 3, and then the mobile station antenna 5. To the mobile stations 6-1 to N.
Similarly, uplink radio waves transmitted from the mobile stations 6-1 to 6 -N are received by the mobile station antenna 5, amplified by the wireless relay amplification device 3, and then transmitted from the base station antenna 4 to the base station 1. Sent out.
[0004]
The wireless relay amplifying apparatus 3 of such a system generally has a common amplification method for commonly amplifying multi-frequency radio waves in the system, and the wireless relay amplifying apparatus 3 has a high input level to the apparatus. In order to protect the semiconductor of the amplifier from excessive input and to prevent the output of unwanted waves by suppressing the level of intermodulation distortion generated in the amplifier by the input level when multiple frequencies are input In general, an automatic gain control (AGC) function for quickly reducing the gain depending on the state of radio wave input to the apparatus is provided.
[0005]
In the system of FIG. 1, the normal service area where the AGC function of the wireless relay amplification device 3 is not operating is 7-2, and mobile stations within this service area 7-2 can talk, When the mobile station 6-1 in the vicinity of the mobile station antenna 5 makes a call, the input level of the radio relay amplifying device 3 becomes very high, the AGC function operates and the gain of the radio relay amplifying device 3 decreases. Therefore, the service area by the wireless relay amplifying device 3 at this time becomes narrow as 7-1, and there is a problem that the mobile stations 6-2 to N outside the service area 7-1 cannot talk. .
[0006]
FIG. 2 shows an example of a conventional configuration of the wireless relay amplifying device 3. 2, the configuration and operation of the uplink from the base station to the base station from the mobile station and downlink to the mobile station, since in principle the same will be described uplink.
[0007]
Radio waves from the mobile station input from the mobile station antenna 5 pass through the mobile station duplexer 12, pass through the uplink AGC attenuator 14, are amplified by the uplink amplifier 16, and pass through the uplink directional coupler 18. The signal is transmitted from the antenna for base station 4 to the base station via the duplexer for base station 11. Further, the uplink signal extracted by the uplink directional coupler 18 is input to the uplink AGC control unit 20, and the uplink AGC control unit 20 attenuates the uplink AGC when the input level becomes high. It works to increase the attenuation of the device 14, lowers the gain of the radio relay amplifying device 3, suppresses the transmission output, and does not exceed a certain level.
The uplink AGC attenuator 14 is provided at the position on the input side of the uplink amplifying unit 16 for the purpose of protecting the input of the uplink amplifying unit 16 and suppressing the occurrence of intermodulation distortion. And the increase in the amount of attenuation of the uplink AGC attenuator 14 is the same as the deterioration of the uplink noise figure of the radio relay amplifying device 3 by the increase in the amount of attenuation. In addition to the problem of narrowing the service area, there is also a problem of deterioration of communication line quality.
[0008]
[Problems to be solved by the invention]
In order to solve this problem, it is necessary to construct an amplification unit in which the AGC function is difficult to operate by using an amplifier having a high saturation output to increase the linearity of the amplification unit and increasing the AGC operation level. In this method, the number of uplink lines input to the radio relay amplifying apparatus 3 and its level are not always constant, and the number of lines increases or decreases depending on the installation location and time zone. Since the level fluctuates depending on the distance to the uplink amplifier 16, the uplink amplifying unit 16 considers the condition that the input is most severe, that is, the condition that the number of input lines is the largest and the condition that the input level is the highest, When the saturation output is determined, the power consumption becomes large, and depending on the line condition at that time, there is a disadvantage that the apparatus consumes very wasted power.
[0009]
The object of the present invention is to solve the narrowing of the service area and the deterioration of the communication line quality due to the AGC function operation which is a problem of the prior art, and economical consumption according to the situation such as the number and level of relayed lines. An object of the present invention is to provide a wireless relay amplification device that can service a dead zone with electric power.
[0010]
[Means for Solving the Problems]
The radio relay amplification apparatus of the present invention is a bidirectional radio relay amplification apparatus that relays and amplifies a downlink signal from a base station to a mobile station and an uplink signal from the mobile station to the base station.
For AGC sequentially connected from the signal input side to each of the downlink and uplink between the duplexer connected to the base station antenna and the duplexer connected to the mobile station antenna An attenuator, an amplifying unit in which a plurality of amplifiers are connected in parallel or in cascade, and a directional coupler;
A line condition detection unit and a line control unit connected between the directional coupler and the AGC attenuator;
Each line status detection unit detects channel status information such as the number of channel signals and signal level from the channel signal extracted by the directional coupler of each of the downlink and the uplink, and based on the channel status information Each of the line control units is configured to perform control to change a saturation output by switching a connection combination of the plurality of amplifiers of each amplification unit .
[0011]
In addition, each line control unit of the wireless relay amplifying apparatus of the present invention is configured to perform control to increase or decrease the attenuation amount of the AGC attenuator based on the line status information.
Furthermore, each line control unit of the wireless relay amplification device according to the present invention can control power to be turned off for an amplifier that is not used among a plurality of amplifiers of the amplification unit according to a combination of connections, thereby reducing power consumption. It is comprised as follows.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 is a diagram showing an example of the configuration of the wireless relay amplification apparatus according to the present invention. In the figure, 21 and 22 are duplexers, 23 and 24 are attenuators, 25 and 26 are amplifying units, and 27 and 28 are directional couplers. Reference numerals 29 and 30 denote downlink and uplink channel status detection units added according to the present invention, and reference numerals 31 and 32 denote downlink and uplink channel control units.
[0013]
Since the configuration and operation of the downlink and uplink are basically the same, only the uplink will be described.
The uplink signal transmitted from the mobile station and input to the radio relay amplifying apparatus passes through the duplexer 22 for mobile station, is amplified by the uplink amplifying unit 26 via the attenuator 24 for uplink AGC, and is directed to the uplink directionality. The signal is transmitted from the wireless relay amplification device to the base station through the coupler 28 and the base station transmission / reception duplexer 21.
[0014]
The uplink signal extracted by the uplink directional coupler 28 is input to the uplink status detection unit 30, where the number of uplink line signals, signal level, etc. are detected, and this uplink line is detected. Based on the status information, the uplink control unit 32 sends an amplifier connection switching signal to the uplink amplification unit 26. In the amplifying unit 26, a plurality of (stage) amplifiers are connected in multiple stages in parallel or in cascade. The uplink amplifier 26 switches the connection combination of the individual amplifiers by this switching signal, and the saturation output of the uplink amplifier 26 is changed. Then, depending on the combination of connections, the power supply of the amplifier that is not used is cut off to suppress wasteful power consumption.
[0015]
Even when the saturation output of the uplink amplifying unit 26 is maximum, when there is an input of the number of channel signals or signal level that causes intermodulation distortion that becomes an unnecessary wave of a certain level or more, the uplink control unit 32 The amount of attenuation of the uplink AGC attenuator 24 is increased to reduce the input level of the amplifying unit 26.
[0016]
The operation principle is the same for the downlink as well. In FIG. 3, the uplink and downlink circuits are configured to change the saturation outputs of the respective amplifiers 25 and 26 independently. Alternatively, the configuration may be such that the saturation outputs of both the uplink and downlink amplifying units are simultaneously changed based on the channel status information such as level and level.
[0017]
The switching of the connection combination of a plurality of amplifiers in the amplifying unit described with reference to FIG.
FIG. 4 is a structural example of a detailed circuit of the amplifying units 25 and 26 used in the present invention. In the figure, reference numeral 40 denotes an amplifying unit showing the first embodiment. Reference numerals 33, 34, and 35 denote amplifiers, and 36, 37, 38, and 39 denote line changeover switches.
[0018]
In the amplification unit 40 of FIG. 4, three amplifiers 33 to 35 having different saturation outputs are arranged in the order of the saturation output, and the amplifier with the highest saturation output is the amplifier 35 at the final stage. In the amplification unit 40 having such a configuration, the line changeover switch 36 is normally connected to the contact 36-b, and the line changeover switch 37 is connected to the contact 37-b. The line switching signal 38 is connected to the contact 38-a, and the line switching switch 39 is connected to the contact 39-a.
At this time, the signal input to the amplifier 40 is amplified by the amplifier 33 via the line changeover switch 36, further amplified by the amplifier 34 via the line changeover switch 37, and output via the line changeover switches 38 and 39. At this time, the amplifier 35 through which no signal passes is turned off by an amplifier connection switching (AMP ON / OFF) signal.
[0019]
Next, when it becomes necessary to increase the saturation output of the amplifier 40 depending on the number of signal lines and the signal level of the relayed radio wave, the amplifier 35 is turned on by the AMP ON / OFF signal, and the line changeover switches 36-39. Are connected to the contacts 36-a, 37-a, 38-b, 39-b by a switching signal, respectively, and the amplifier 33 is powered off by an AMP ON / OFF signal.
At this time, the signal input to the amplification unit 40 is amplified by the amplifier 34 via the line changeover switches 36 and 37, further amplified by the amplifier 35 via the line changeover switch 38, and output via the line changeover switch 39. .
In this way, the saturation output of the amplifying unit 40 can be changed by switching the connection combination of the amplifiers 33 to 35.
[0020]
FIG. 5 is a structural diagram showing another embodiment of the amplifying units 25 and 26 used in the present invention. In the figure, reference numeral 50 denotes an amplifying unit of the second embodiment. Reference numerals 41 and 42 denote amplifiers, and reference numerals 43, 44, 45, and 46 denote line changeover switches. 47 is a distributor and 48 is a combiner.
[0021]
The amplifier unit 50 shown in FIG. 5 includes amplifiers 41 and 42 having equal saturation outputs connected in parallel. Normally, the line selector switches 43 to 46 are connected to each other, and the switch 43 is connected to (2) and (3), respectively. ▼, switch 44 is connected to (1) and (4), switch 45 is connected to (2) and (3), and switch 46 is connected to (1) and (4).
At this time, the signal input to the amplifying unit 50 is amplified by the amplifier 41 via the line changeover switches 43 and 44 and output via the line changeover switches 45 and 46. At this time, the amplifier 41 is turned on by the AMP ON / OFF signal, and the amplifier 42 is turned off.
[0022]
Next, when it is necessary to increase the saturation output of the amplifier 50 depending on the number of signal lines and the signal level of the relayed radio wave, the amplifier 42 is turned on by the AMP ON / OFF signal, and the line changeover switches 43 to 46 are turned on. The switch 43 is connected to (2) and (4), the switch 44 is connected to (2) and (4), the switch 45 is connected to (2) and (4), and the switch 46 is connected to (2) and (4). To be.
At this time, the signal input to the amplifying unit 50 is distributed by the distributor 47 via the line changeover switch 43, and one of the signals is amplified by the amplifier 41 via the line changeover switch 44 and passes through the line changeover switch 45. 48 is input. The other signal is amplified by the amplifier 42 and input to the synthesizer 48. Both signals synthesized by the synthesizer 48 are output through the line changeover switch 46.
In this way, the saturation output of the amplification unit 50 can be changed.
[0023]
It is clear that the saturation output can be changed also in the amplifying unit configured by variously combining the configuration shown in FIG. 4 and the configuration shown in FIG.
[0024]
【The invention's effect】
As described above in detail, according to the present invention, the required service area and the communication line quality can be ensured even if the number of line signals to be relayed and the line signal level are changed. Since the dead zone can be serviced with necessary and sufficient economic power consumption according to the line conditions, the practical effect is great.
[Brief description of the drawings]
FIG. 1 is a configuration example diagram of a wireless relay amplification apparatus system to which the present invention is applied.
FIG. 2 is a configuration example diagram of a conventional wireless relay amplification apparatus.
FIG. 3 is a configuration example diagram of a wireless relay amplification apparatus according to the present invention.
FIG. 4 is a configuration example diagram showing a first embodiment of an amplifying unit of the present invention;
FIG. 5 is a configuration diagram showing another embodiment of the amplifying unit of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base station 2 Base station antenna 3 Wireless relay amplifier 4 To base station antenna 5 To mobile station antenna 6-1 to N mobile station 7-1 to 2 Service area 11 To base station duplexer 12 To mobile station duplexer 13 Downlink AGC Attenuator 14 Uplink AGC Attenuator 15 Downlink Amplification Unit 16 Uplink Amplification Unit 17 Downlink Directional Coupler 18 Uplink Directional Coupler 19 Downlink AGC Control Unit 20 Uplink AGC Control Unit 21 Duplexer for Base Station 22 Duplexer for Mobile Station 23 Attenuator for Downlink AGC 24 Attenuator for Uplink AGC 25 Downlink Amplifier 26 Uplink Amplifier 27 Downlink Directional Coupler 28 Uplink Directionality combiner 29 downlink channel condition detector 30 uplink line status detecting unit 31 downlink control unit 32 uplink control section 33 to 35 amplification 36-39 line selector switch 40 the amplifying unit 41 amplifier 43 through 46 line selector switch 47 divider 48 synthesizer 50 amplifying section

Claims (3)

In a bidirectional radio relay amplification apparatus that relays and amplifies a downlink signal from a base station to a mobile station and an uplink signal from the mobile station to the base station,
For AGC sequentially connected from the signal input side to each of the downlink and uplink between the duplexer connected to the base station antenna and the duplexer connected to the mobile station antenna An attenuator, an amplifying unit in which a plurality of amplifiers are connected in parallel or in cascade, and a directional coupler;
A line condition detection unit and a line control unit connected between the directional coupler and the AGC attenuator;
Each line status detection unit detects channel status information such as the number of channel signals and signal level from the channel signal extracted by the directional coupler of each of the downlink and the uplink, and based on the channel status information Each of the line control units is configured to perform control to change a saturation output by switching a connection combination of the plurality of amplifiers of each of the amplification units. 2. The radio relay amplifying apparatus according to claim 1, wherein each of the line control units is configured to perform control to increase or decrease an attenuation amount of the AGC attenuator based on the line status information . Each of the line control units is configured to be able to reduce power consumption by performing control so that an amplifier that is not used among a plurality of amplifiers of the amplification unit is not used depending on a combination of connections. The wireless relay amplification device according to 1.

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