KR20090028096A - Method and apparatus for controlling oscillation of mobile communication repeater - Google Patents

Abstract

A method and an apparatus for continuously supporting a service and controlling the gain of relay according to the intensity of the input signal are provided to provide a service continuously by resetting an originating control system without shutting down the system. The degree of isolation between the input-output of the radio frequency is measured(S440). A margin value which is set up according to the radio frequency is taken out of the measured isolation. The operation available max gain in which oscillation is not generated is calculated(S450). The gain value of the radio frequency is used within the calculated operation available max gain(S460). If the input signal is sensed in the radio frequency, it becomes the oscillation control of the radio frequency.

Description

METHOD AND APPARATUS FOR CONTROLLING OSCILLATION OF MOBILE COMMUNICATION REPEATER}

The present invention relates to an oscillation control method and apparatus of a mobile communication repeater, and in particular, an oscillation control method for servicing without shutting down the repeater system even when the repeater cannot service at full power or an oscillation occurs during operation. Relates to a device.

Recently, with the rapid development of mobile communication service, mobile communication service area is expanding to underground parking lot of apartments, underground restaurants, underground shopping malls, etc., and mobile service providers are trying to solve the shadow area and provide higher quality service. Repeater is installed and operated. The mobile communication repeater receives and amplifies the signal of the weak base station through the link antenna and transmits the signal to the mobile station through the service antenna, or receives and amplifies the signal of the mobile station through the service antenna and transmits the signal to the base station through the link antenna.

Currently, hundreds of thousands of small / small size RF repeaters are installed and operated in Korea, and mobile operators are continuously increasing the number of repeaters installed to provide high quality services to consumers. The RF repeater is mainly installed in the basement of the building and is widely used for expanding cell coverage because of low facility cost. However, the operator has a problem that it is difficult to efficiently manage the operation state, such as whether each RF repeater installed throughout the country is operating normally or shut down due to oscillation.

In order for an RF repeater to operate normally, the amplified signal from the RF input source and the equipment must have an adequate level of isolation from each other. Oscillation may occur if there is no more space separation, that is, isolation between the input source link antenna and the service antenna. In general, the oscillation of the repeater can be described as a speaker of karaoke. If there is not enough space between the microphone and the speaker in the karaoke room, the signal from the speaker goes back into the microphone and is amplified by a beeping sound.

When oscillation occurs in a repeater, it has a fatal effect on the neighboring network. Therefore, when the oscillation occurs, the system must be shut down immediately to protect the neighboring network. Therefore, the conventional repeater first checks whether the service is available at the maximum power when the power is turned on, and shuts down the system if the service is not available at the maximum power. In addition, if oscillation occurs during operation, the system is shut down immediately to protect neighboring networks. However, it is inefficient to discontinue the service without considering the strength of the input signal, because the service of maximum power is unavailable or oscillation occurs during operation, and there is a problem that the carrier and the customer have to bear the damage.

Therefore, the present invention does not immediately shut down the system when the mobile communication repeater cannot service at full power or an oscillation occurs during operation, and adjusts the gain of the repeater according to the strength of the input signal or resets the oscillation control system to perform service. An object of the present invention is to provide an oscillation control method and apparatus that can be continuously provided.

In order to achieve the above object, the present invention provides a method for controlling oscillation of a mobile communication repeater, the method comprising: measuring an isolation degree between input and output of the mobile communication repeater and a margin set according to the mobile communication repeater from the measured isolation degree; Calculating a maximum operable gain value by which the oscillation does not occur by subtracting a value; and operating a gain value of the mobile communication repeater within the calculated maximum operable gain value.

In another aspect, the present invention provides a method for controlling the oscillation of a mobile communication repeater, the method comprising the step of resetting the mobile communication repeater when the oscillation occurs during the operation of the mobile communication repeater.

In another aspect, the present invention provides an oscillation control apparatus for controlling oscillation of a mobile communication repeater, wherein oscillation occurs by subtracting means for measuring the isolation degree of the mobile communication repeater and a predetermined value set according to the mobile communication repeater from the measured isolation degree. And a control means for estimating an operable maximum gain value not operating and operating a gain value of the mobile communication repeater within the calculated operable maximum gain value.

According to the present invention as described above, even if it is unable to service at the maximum power of the mobile communication repeater, it is possible to operate by adjusting the gain of the mobile communication repeater according to the size of the input signal. In addition, even when oscillation occurs during operation, the oscillation control system can be reset without providing an unconditional shutdown of the mobile communication repeater system, thereby providing continuous service. Therefore, the mobile communication company can efficiently operate and manage the existing mobile communication repeater, and the consumer can be provided with high quality service even in the area where the signal is weak such as the underground parking lot of the apartment.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, whereby those skilled in the art may easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram briefly showing a configuration of a mobile communication relay system to which the present invention is applied. As shown, the mobile communication relay system includes a repeater 100, a base station 110, and a mobile station 120.

The mobile communication repeater 100 receives the signal of the weak base station through the input source link antenna 102, amplifies the received signal and transmits the received signal to the mobile station 120 through the service antenna 104. Alternatively, the signal of the mobile station 120 is received through the service antenna 104, and the received signal is amplified and transmitted to the base station 110 through the input source link antenna 102.

Isolation Measurements> Repeater Gain

As such, when the repeater 100 does not satisfy Equation 1 in the process of amplifying and outputting an input signal, oscillation occurs. In other words, oscillation occurs when the isolation between the input source link antenna 102 and the service antenna 104 is less than the gain of the repeater 100. Therefore, in order to prevent the oscillation phenomenon, the isolation between the input source link antenna 102 and the service antenna 104 should be secured to a predetermined level or more, or the gain of the repeater should be adjusted. However, in order to secure the degree of isolation of the repeater 100 is already installed, the repeater must be reinstalled, which means an additional burden of facility costs. In addition, there is a problem that customer service is not available until the repeater is reinstalled. Therefore, it is more effective to prevent oscillation by adjusting the gain of the repeater for efficient operation of the existing repeater.

2 is a view showing the flow of the mobile communication repeater oscillation control method according to the prior art. When the power of the repeater is turned on (S210), the repeater first checks the isolation (Ssolation). Then, it is determined whether the corresponding repeater can service at maximum power by Equation 1 (S230). Here, the maximum power refers to the repeater output when the repeater uses the maximum gain value that can be operated, and provides the service with the maximum power when the repeater is operated at the maximum gain value. If it is determined that the service is possible at the maximum power of the repeater, the repeater operates the repeater with the maximum gain value as the limit (S240). And if oscillation occurs during operation (S250) immediately shuts down the system of the repeater to protect the adjacent network (S260). If the repeater cannot provide the service at full power (S230), the repeater immediately shuts down the system to protect the neighboring network (S260). Therefore, the conventional repeater determines whether the oscillation is considered in consideration of the maximum gain value unconditionally without considering the strength of the input signal, and immediately shuts down the system when the oscillation occurs during operation. The repeater thus discontinued the service, which led to customer dissatisfaction.

In a mobile communication network, the external environment often changes in strength of an input signal input to an input source link antenna by the establishment, relocation, relocation, or optimization of an output of a base station or an outdoor large repeater. In addition, the repeater installed in the basement of the building is turned on and off once a day due to the nature of the installation space. Therefore, in order to provide a proper service according to the ever-changing environment, it is necessary to have the intelligence such as adjusting the gain by the repeater itself and resetting the system by itself if necessary.

3 is a view showing the flow of the method of controlling the oscillation by the reset of the present invention, which adds a reset function in the oscillation control system of the conventional repeater. When the repeater is powered on (S310), the repeater first checks isolation (S320). Then, it is determined whether the corresponding repeater can service at maximum power according to Equation 1 (S330). Here, the maximum power refers to the repeater output when the repeater uses the maximum gain value that can be operated, and provides the service with the maximum power when the repeater is operated at the maximum gain value. If it is determined that the repeater can be serviced at the maximum power, the repeater operates the repeater with the maximum gain value as the limit (S340).

Isolation Measurements> Repeater Gain Values + Predetermined Values (A)

In determining whether oscillation occurs, Equation 2 is preferably used. In the process of measuring the isolation between the input source link antenna 102 and the service antenna 104 and comparing it with the gain value of the repeater, a predetermined value (A) is applied to the repeater gain value in order to stabilize the system. Add 15 to 20 dB and compare. The gain value of the repeater in Equation 2 refers to the limit value of the gain value in which the repeater can be operated. Therefore, when the limit value and the isolation measurement value are directly compared, even if a slight error occurs, the system may have a fatal effect. have. Therefore, when determining whether or not oscillation is performed, the gain value of the repeater is added to a predetermined value (A) set according to the repeater, compared with the actual isolation measurement value, and the value obtained by adding the predetermined value (A) to the gain value of the repeater is the isolation degree. If it is larger than the measured value, oscillation occurs.

If the repeater cannot operate the repeater at full power (S330), the repeater resets the oscillation control system (S370). In addition, it is possible to determine whether to reset or shut down the oscillation control system by determining whether the number of times the system has been reset to the present time after the power is turned on or more (S350). The limit number is a value set by the operator as a criterion for determining whether the oscillation has occurred accidentally or continuously. As a result of the determination, when the repeater is reset more than the limit number, since the oscillation is continuously generated, the system of the repeater is shut down (S360). If the repeater reset count is less than or equal to the limit, the repeater is reset again (S370) and the oscillation control system is started again from the beginning. At this time, the total number of resets is increased by one (S380).

In addition, if oscillation occurs during operation of the repeater, the conventional repeater immediately shuts down the system, but according to the present invention, the oscillation control system is reset to check again whether the repeater can be serviced at full power. Therefore, if the oscillation occurs temporarily, the system of the repeater is not shut down unconditionally. In addition, the number of resets is reviewed, and when the reset is performed for a predetermined number of times, the system of the repeater is shut down.

This reset function prevents accidental oscillation from leaving the system of the repeater shut down and if oscillation occurs continuously, the system of the repeater is shut down after a limited number of resets, so that the neighboring network can be reliably protected. have.

4 is a diagram showing the flow of a method for controlling oscillation by calculating the maximum operational gain value calculation of the present invention.

When the repeater is powered on (S410), the repeater first checks the isolation (Ssolation). In addition, it is determined whether the oscillation occurs when the repeater services the full power (S430). Here, the maximum power refers to the repeater output when the repeater uses the maximum gain value that can be operated, and provides the service with the maximum power when the repeater is operated at the maximum gain value. The oscillation is determined by Equation 1 and it is considered that oscillation does not occur when the isolation measurement value is larger than the repeater gain value. If it is determined that the repeater can be serviced at full power, the repeater operates the repeater with the maximum gain limit (S460). If the repeater cannot operate the repeater at full power (S430), the input source link antenna and service By measuring the isolation of the antenna (S440) to calculate the maximum operational gain (S450).

Isolation Measure-Margin = Maximum Gain Gain

The calculation of the maximum gain value that can be operated is based on Equation 3. Since the isolation value can be regarded as the threshold value that oscillation does not occur, the maximum gain value that can be operated is calculated by subtracting the margin value set according to the mobile communication repeater from the isolation level to improve the stability of the system. Set a margin of about 1 to 3 dB.

For example, when the maximum gain value of the repeater is 100dB and the isolation measurement value is 90dB, it is determined that oscillation occurs because Equation 1 is not satisfied. Therefore, the maximum operational gain is calculated. If the isolation measurement is 90 dB, 87 dB minus the 3 dB margin is considered to be the maximum gain for operational stability. The related expressions are as follows.

Isolation Measurement (90 dB)> Repeater Gain (100 dB)

: Estimation of maximum gain that can be operated because it is not satisfied

Isolation Measurement (90dB)-Margin (3dB) = Maximum Operable Gain (87dB)

The maximum gain value that can be operated is calculated through the above process, and the maximum gain value that can be operated can be calculated by measuring the isolation value once, but preferably, the measured maximum gain value is measured by repeatedly measuring the isolation value. Select the minimum value as the maximum operational gain. When the maximum operational gain is calculated, the repeater is operated within the maximum operational gain (S460). In other words, operate the repeater by selecting the gain value that can produce the proper output according to the input signal with the maximum operable gain value as the maximum value.

Also in this embodiment, as described above, it is determined whether the oscillation is generated by Equation (2). In the process of measuring the isolation between the input source link antenna and the service antenna and comparing it with the gain value of the repeater, add a predetermined value A (15 to 20 dB) to the repeater gain value to improve system stability. do. The gain value of the repeater in Equation 2 refers to the limit value of the gain value that can be used to operate the repeater. Therefore, when the limit value and the isolation measurement value are directly compared, even if a slight error occurs, the system may have a fatal effect. . Therefore, when determining whether or not oscillation is performed, the gain value of the repeater is added to a predetermined value (A) set according to the repeater, compared with the actual isolation measurement value, and the value obtained by adding the predetermined value (A) to the gain value of the repeater is the isolation degree. If it is larger than the measured value, oscillation occurs.

The oscillation does not occur when the gain value of the repeater is added to the gain value of the repeater and compared with the isolation measurement value, and the gain value of the repeater plus the predetermined value A is smaller than the isolation measurement value. see. If it is determined that the repeater can service at maximum power, the repeater operates the repeater with the maximum gain value as the limit. If the repeater cannot operate the repeater at full power, the maximum gain value can be calculated by measuring the isolation between the input source link antenna and the service antenna.

{Isolation Measured Value-Predetermined Value (A)}-Margin = Operating Maximum Gain

When oscillation is determined by Equation 2, the maximum gain value that can be operated is calculated by Equation 4. In order to ensure the stability of the system when determining whether the system is oscillated, a certain value (A) is added to the repeater gain value and compared with the isolation measurement value. Subtract A). In addition, since the isolation measure can be regarded as the boundary value without oscillation, the maximum gain value that can be operated is calculated by subtracting the margin value from the isolation to increase the stability of the system. The margin can be set to about 1 to 3 dB.

For example, when the maximum gain value of the repeater is 85 dB, the isolation value is compared with the value obtained by adding 15 dB of the predetermined value (A) set according to the repeater. If the isolation measurement value is 90 dB, the oscillation occurs because the maximum gain value of the repeater is smaller than 100 dB plus a predetermined value (A) 15 dB, which does not satisfy the equation (2). Therefore, the maximum operational gain is calculated. If the isolation measurement is 90 dB, subtract 75 dB minus 15 dB for A. In order to stabilize the system, 72dB minus 3dB margin is regarded as the maximum gain. The related expressions are as follows.

Isolation measurement (90 dB)> repeater gain (85 dB) + predetermined value (A) (15 dB)

: Estimation of maximum gain that can be operated because it is not satisfied

{Isolation measurement value (90dB)-predetermined value (A) (15dB)}-margin value (3dB) = operational maximum gain value (72dB)

The maximum operational gain can be calculated through the above process.

When the operator arbitrarily sets the limit of gain value at which the repeater operates, the operator shall set the limit within the calculated maximum gain value.

For example, if the maximum operational gain is estimated at 70 dB and the operator attempts to set 100 dB to the limit of the gain, then the input will not be set. Alternatively, even if the operator sets 100 dB, the operating maximum gain value of 70 dB is set as the limit of the gain value.

5 is a flowchart illustrating a method of controlling oscillation when an input signal of the present invention is detected.

The processing method in the case where the input signal to the repeater is detected before the maximum operational gain is calculated or while the maximum operational gain is calculated. If the input signal is not detected in the process of measuring the isolation (S510) and calculating the maximum operational gain (S530), the repeater is operated using the maximum operational maximum gain (S540). However, if an input signal to the repeater is detected before calculating the maximum gain value or during the operation, the oscillation control of the repeater is held for several seconds (S550). For example, if the input signal is detected after measuring the isolation level, the repeater will hold the oscillation control system for a predetermined time set by the operator, and then resume oscillation control if the input signal is lost. This hold function allows the repeater to provide reliable service to the customer.

6 is a flowchart of a method for controlling oscillation using a cutoff gain value of the present invention.

The maximum gain value that can be operated is calculated by measuring the isolation between the input source link antenna and the service antenna of the repeater (S610). The operational maximum gain value can be calculated by Equation 3 as described above with reference to FIG. 4, and preferably by Equation 4. In addition, the maximum operational gain can be calculated by measuring the isolation once, but preferably, the isolation is repeatedly measured several times, and a minimum value of the maximum operational maximum gain calculated from the measured isolation is used. If the selected maximum gain value is greater than the minimum gain value set by the operator, that is, the cutoff gain, the repeater is operated within the maximum gain value (S640). However, when the calculated maximum operational gain is less than the minimum gain set by the operator, that is, cutoff gain (S630), the repeater is reset (S660). In addition, before resetting the repeater, the number of resets is reviewed (S650). If the operator resets the predetermined number of times or more, the system of the repeater may be shut down (S680). For example, the cutoff gain of a small repeater is set to 58 dB, and the cutoff gain of a small repeater is set to 48 dB. When the operational maximum gain of the small repeater is 50dB, the oscillation control system is reset because the repeater cannot guarantee the minimum gain. If the repeater is reset more than 4 times, oscillation can be regarded as continuous, so shut down the system of the repeater to protect the neighbor network.

7 is a view showing the flow of the oscillation control method for reporting the state of the repeater to the operator of the present invention.

The maximum gain value that can be operated is calculated by measuring the isolation between the input source link antenna and the service antenna of the repeater (S710). The operational maximum gain value can be calculated by Equation 3 as described above with reference to FIG. 4, and preferably by Equation 4. The maximum operational gain can be calculated by measuring the degree of isolation once, but preferably, the degree of isolation is measured several times and selected and used the minimum of the maximum operational gains calculated from the measured degree of isolation. In this case, if the maximum operable gain value selected is greater than the predetermined gain value set by the operator (S730), it means that the current repeater has secured some degree of operation and reports the current status of the repeater to the operator (S740). ). The repeater is operated with the maximum operational gain as the maximum value (S750).

This allows operators to efficiently manage tens of thousands of repeaters installed across the country. Currently, there are hundreds of thousands of repeaters installed in the country, but once installed, the reality is that they are not properly managed. Even though the system is shut down due to problems such as oscillation after installation, it is about 5 to 10% of the total installed repeaters, which does not provide any service, but the operator does not know the operation status of the repeater accurately. It is leading to dissatisfaction. In addition, the operator can not determine how much profit the repeater is currently operating normally.

Therefore, the present invention reports to the operator the status of the repeater, that is, how stable the current repeater is providing the service or to what extent the gain is provided to the operator so that the operator can efficiently manage the repeater. . The status of such repeaters can be reported remotely to the operator.

8 is a flowchart illustrating a method of controlling oscillation by resetting when oscillation occurs during operation of a repeater according to the present invention.

The maximum gain value that can be operated is calculated by measuring the isolation between the input source link antenna and the service antenna of the repeater (S810). The operational maximum gain value can be calculated by Equation 3 as described above with reference to FIG. 4, and preferably by Equation 4. The maximum operational gain can be calculated by measuring the degree of isolation once, but preferably, the degree of isolation is measured several times and selected and used the minimum of the maximum operational gains calculated from the measured degree of isolation. If oscillation occurs while operating the repeater (S830) with the maximum operable gain value as the maximum value (S840), the repeater is reset (S860). When the repeater is reset, the system restarts from the beginning, so the isolation is measured to recalculate the maximum operational gain. If the number of resets of the repeater is more than the operator's limit, the oscillation can be regarded as continually occurring, so shut down the system of the repeater immediately. In addition, if oscillation occurs during operation, the repeater can be operated by measuring the isolation again to calculate the maximum operational value without resetting.

1 is a block diagram of a mobile communication relay system to which the present invention is applied.

2 is a flow chart of a mobile communication repeater oscillation control method according to the prior art.

3 is a flow chart of the oscillation control method by the reset of the present invention.

4 is a flowchart of an oscillation control method through calculation of an operational maximum gain value of the present invention;

5 is a flowchart of an oscillation control method when an input signal of the present invention is detected.

6 is a flowchart of an oscillation control method using a cutoff gain value of the present invention.

7 is a flowchart of an oscillation control method for reporting a state of a repeater to an operator of the present invention.

8 is a flowchart of an oscillation control method by resetting when oscillation occurs during operation of a repeater of the present invention.

Claims (13)

In the method of controlling the oscillation of a mobile communication repeater, Measuring an isolation degree between input and output of the mobile communication repeater; Calculating a maximum operable gain value without oscillation by subtracting a margin value set according to the mobile communication repeater from the measured isolation degree; Operating a gain value of the mobile communication repeater within the calculated operational maximum gain value; Oscillation control method comprising a. The method of claim 1, The isolation is measured over a number of iterations, and the minimum of the operational maximum gains calculated from the isolation measured over the several iterations is selected. An oscillation control method characterized by the above-mentioned. The method of claim 1, Holding an oscillation control of the mobile communication repeater for a predetermined time when an input signal is detected by the mobile communication repeater; Oscillation control method characterized in that it further comprises. The method of claim 1, Resetting the mobile communication repeater when the calculated maximum operational gain is less than the minimum gain set by the operator. Oscillation control method characterized in that it further comprises. The method of claim 4, wherein Counting the number of times of resetting the mobile communication repeater and shutting down the mobile communication repeater when the threshold number of times is reset. Oscillation control method characterized in that it further comprises. The method of claim 1, Reporting the calculated maximum gain value to the operator if the calculated maximum gain value is greater than the threshold gain value set by the operator. Oscillation control method characterized in that it further comprises. The method of claim 1, Resetting the mobile communication repeater when oscillation occurs during operation of the mobile communication repeater. Oscillation control method characterized in that it further comprises. The method of claim 1, When the operator arbitrarily sets the gain value of the mobile communication repeater, the operator may set the gain value only within the calculated operational maximum gain value. An oscillation control method characterized by the above-mentioned. An oscillation control device for controlling oscillation of a mobile communication repeater, Means for measuring an isolation degree of the mobile communication repeater; The operation maximum gain value without oscillation is calculated by subtracting a predetermined value set according to the mobile communication repeater from the measured isolation degree, and operating the gain value of the mobile communication repeater within the calculated operational maximum gain value. Control means An oscillation control device comprising: The method of claim 9, The control means, Measuring the isolation repeatedly several times and selecting the minimum of the maximum operational gains calculated from the isolation measured repeatedly several times. Oscillation control device characterized in that. The method of claim 9, The control means If the calculated maximum gain value is smaller than the minimum gain value set by the operator, the mobile communication repeater is reset, and the number of times of resetting the mobile communication repeater is counted. To shut down Oscillation control device characterized in that. The method of claim 9, The control means Resetting the mobile communication repeater when oscillation occurs during operation of the mobile communication repeater. Oscillation control device characterized in that. The method of claim 9, The control means When the operator arbitrarily sets the gain value of the mobile communication repeater, the operator may set the gain value only within the calculated operational maximum gain value. Oscillation control device characterized in that.

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