KR100970220B1 - Gain Control Method According to Isolation Changes and Wireless Repeater - Google Patents

Abstract

The present invention relates to a gain control method according to a change in isolation and a wireless repeater therefor.

The present invention calculates a gain estimate using the measured average value of the isolation and a preset cancellation limit setting value, and then compares the gain control value set with the wireless repeater to determine a gain control value and determines the gain control value. It provides a gain control method of the wireless repeater to adjust the gain limit through. In addition, the present invention is an isolation calculation unit for measuring the isolation from the input signal; An isolation average value calculator for calculating an average value for the isolation; A gain estimate calculator for calculating a gain estimate using an isolation average value; A gain limit setting unit that adjusts gain through a gain limit value; And a gain control value calculator for calculating a gain control value for changing the gain limit value.

According to the present invention, it is possible to stably operate the mobile communication network by performing a gain adjustment suitable for the corresponding environmental conditions through automatic measurement of the change of isolation and fading in the repeater.

Repeater, Wireless Repeater, Gain Control, Isolation, Isolation, Fading

Description

Gain Control Method According to Isolation Change and Wireless Repeater for It {Method for Controlling Gain using Change for Isolation, and Repeater Therefor}

The present invention relates to a gain control method according to a change in isolation and a wireless repeater for the same. In particular, the present invention relates to a method for controlling gain so as to satisfy an amplification characteristic by measuring the isolation changed by the surrounding environment and the reflected wave in the wireless repeater, and a structure of the wireless repeater therefor.

The repeater is a device that is configured in a shaded area or an area where the installation cost of the base station is burdened in the mobile communication system, receives and amplifies the signal transmitted from the mobile communication system and then retransmits it.

Repeaters are largely classified into a wired repeater connected to a base station by wire and a wireless repeater connected to a base station by wireless.

The wired repeater can maintain good call quality because wired communication is performed between the repeater and the base station. However, the wired repeater is more expensive than the wireless repeater. Has a problem.

On the contrary, since the wireless repeater performs wireless communication between the repeater and the base station, the call quality is inferior to the wired repeater, but it is easy to install and the operation cost is low.

Such a wireless repeater may be more usefully applied than an expensive wired repeater when the area covered by the repeater is small due to the electromagnetic shielding effect of the structure such as the basement inside the building.

The structure of such a wireless repeater is shown in FIG.

The receiving antenna 120 and the receiving unit 1310 of the wireless repeater receive the RF signal transmitted from the base station 110, the feedback cancellation filter 1320 filters only a predetermined signal band from the received RF signal. The RF signal from which the feedback signal is removed is amplified by the amplifier 1330 and then transmitted to the same channel through the transmitter 1340 and the transmit antenna 140.

When such a wireless repeater is installed in an open area, a feedback loop is formed in which a signal transmitted through the transmitting antenna 140 of the wireless repeater feeds back to the receiving antenna 120. The output signal is attenuated by the feedback loop and enters the input. Thus, the amount of attenuation through the feedback loop is called isolation (hereinafter, referred to as 'isolation'). In wireless repeaters, oscillation occurs when the isolation is less than or equal to the gain of the repeater.

The auto level control unit (ALC) 1350 automatically adjusts the gain when the output transmitted through the transmitting antenna 140 is greater than a preset output value, thereby repeating the repeater ( 130) performs a function to adjust to provide a smooth service without oscillation.

However, in the method of adjusting the gain using the ALC 1350 as described above, the gain is adjusted according to the output. Thus, even if the isolation value in the repeater 130 changes, the output of the repeater 130 is previously set to the upper limit of the ALC. If the output does not reach the output, the oscillation may not perform a gain adjusting procedure, so the quality of service may be degraded due to the oscillation.

The technical problem to be achieved by the present invention is a method for measuring the Isolation changed by the surrounding environment and the reflected wave in the repeater, calculating the maximum gain estimate by using the average value and the cancellation value limit set value in the measured isolation and the gain control method and It is to provide a structure of a wireless repeater for this purpose.

To this end, a gain adjusting method according to an embodiment of the present invention is a method of adjusting a gain of a wireless repeater, comprising: (a) measuring an isolation from a received signal; (b) calculating a gain estimate using the measurement result of the isolation; (c) comparing the gain estimate with the magnitude of the gain limit set in the wireless repeater to determine a gain control value; And (d) adjusting a gain limit value set in the wireless repeater using the gain control value.

In addition, the wireless repeater according to the embodiment of the present invention is a wireless repeater for adjusting the gain according to the change of the isolation, the isolation calculator for measuring the isolation from the input signal received through the receiving antenna of the wireless repeater; A gain estimation calculator for calculating a gain estimate using the isolation calculated by the isolation calculator; A gain limit setting unit configured to perform gain control in the wireless repeater using the set gain limit value; And a gain control value calculating section for calculating a gain control value for changing the gain limiting value according to a comparison result of the gain limiting value set in the gain limiting value setting section and the gain estimation value calculated in the gain estimation value calculating section.

According to an embodiment of the present invention, by using the existing gain control method in the environment conditions with severe isolation and fading changes, it is possible to improve the part that it was difficult to maintain the smooth performance of the repeater, ILC (Interference Level Control) function and elimination value The limit setting value (X _th ) setting function enables automatic measurement of the isolation and fading change to adjust the gain according to the environmental conditions and maintain smooth performance. Accordingly, the mobile communication network can be stably operated in the repeater.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

2 is a block diagram schematically showing the internal configuration of the repeater according to the embodiment of the present invention.

The repeater 220 according to the embodiment of the present invention includes a receiver 2202, a feedback cancellation filter 2204, an amplifier 2206, a transmitter 2208, an isolation calculator 2210, an input unit 2212, and a memory unit ( 2214, a display unit 2216, an isolation average value calculator 2218, a gain estimation value calculator 2220, a comparison unit 2222, a gain control value calculation unit 2224, and a gain limit value setting unit 2226.

The receiver 2202 is a part that receives an input signal received through the reception antenna 210. In this case, the input signal received through the receiver 2202 is a signal in which the original signal transmitted from the base station 110 and the feedback signal transmitted through the transmission antenna 230 are combined.

The feedback cancellation filter 2204 filters the feedback signal among the signals received through the receiver 2202.

The amplifier 2206 serves to amplify the signal filtered by the feedback cancellation filter 2204 in order to retransmit the signal.

The transmitter 2208 transmits the signal amplified by the amplifier 2206 through the transmission antenna 230.

The isolation calculator 2210 estimates the isolation by using the power value of the input signal received through the receiver 2202 and the power value of the feedback signal checked by the feedback cancellation filter 2204. Here, the isolation calculation unit 2210 calculates isolation in a predetermined time unit and transfers the calculated value to the memory unit 2214 according to an embodiment of the present invention.

The input unit 2212 is used for inputting a threshold value of a cancel value Cancel set by a user for filtering in the feedback cancellation filter 2204 and commands of various programs for operating a repeater. Part. In the following description, the erase limit value set by the user through the input unit 2212 will be described as 'X _th '.

The memory unit 2214 stores a program for controlling the overall operation of the repeater 220, and according to an embodiment of the present invention, an isolation value calculated by the isolation calculator 2210 and an X input through the input unit 2212. Stores the _th value. In addition, the gain limit setting unit 2226 stores a gain limit value calculated through.

In addition, the memory unit 2214 may provide the isolation value stored in the isolation average value calculator 2218, the X _th value stored in the gain estimate calculator 2220, or the comparator 2222 and the display 2216. It also serves to provide a stored gain limit.

Isolation average value (hereinafter, referred to as 'I _means ') calculation unit 2218 calls one or more isolation values stored in the memory unit 2214 in a preset time unit, and averages one or more isolation values. It calculates I _means which is average value of isolation.

In carrying out the present invention, various modifications may be used, such as adding or subtracting a specific number to the I _means , but the following description will be based on using the average value as it is.

Gain estimate calculation unit 2220 using the X _th values that are passed from the I _means the memory 2214 calculated by the calculating _means I unit 2218, and performs a function for calculating the instantaneous gain estimates. In implementing the present invention, the gain estimation calculator 2220 preferably calculates an instantaneous maximum gain estimate G _means (hereinafter, referred to as G _means ), and in the following description, the gain estimate calculator 2220 is described. _Will be explained based on the calculation of the maximum gain, G _means . The gain estimation calculator 2220 calculates G _means through Equation 1 using I _means and X _th values.

G _means = I _means + X _th

Here, one can be used by variously modifying the like which will be added to or subtracted from the specified number to the summation result of the I _means the X _th value according as the calculated G _means, in the following description using a combined result of the I _means the X _th value as This will be described as a reference.

The comparison unit 2222 compares the G _means calculated by the gain estimation unit 2220 with the magnitude of the gain limit value stored in the memory unit 2214, and transmits the result to the gain control value calculation unit 2224. Perform the function.

The gain control value calculator 2224 performs a function of calculating the gain control value ΔG according to the comparison result transmitted from the comparator 2222. Here, according to the embodiment of the present invention, when the result of the 'G _means > gain limit value' is received from the gain control value calculating unit 2224 comparison unit 2222, the gain control value ΔG is set to a positive value. When the result of 'G _means <gain limit value' is received from the comparator 2222, the gain control value DELTA G is set to a negative value, and from the comparator 2222, 'G _means = gain limit value' is obtained. Upon receiving the result, the gain control value ΔG is set to '0'. Here, the description will be made based on setting the gain control value to '+1' when G _means > gain limit value and setting the gain control value to '-1' when G _means <gain limit value.

The gain control value calculator 2224 transfers the calculated gain control value ΔG to the gain limit value setting unit 2210.

The gain limit setting unit 2210 changes the gain limit set in advance according to the gain control value DELTA G transmitted from the gain control value calculating unit 2224, and resets the changed gain limit to the gain limit. do. Then, the gain control in the repeater 220 is performed using the reset gain limit value. In addition, the gain limit setting unit 2210 transfers and stores the reset gain limit value to the memory unit 2214 so that the reset gain limit value can be used for the size comparison in the comparison unit 2222.

Here, the gain limit value setting unit 2210 sets the maximum gain limit value G _max , hereinafter referred to as 'G _max ', among the plurality of gain limit values as the gain limit value, and the maximum gain limit value G also in the following description. _It will be described based on calculating the gain control value by performing size comparison with G _means using _max ).

Here, in amplifying and transmitting the RF signal received from the receiving antenna 120 to the transmitting antenna 140 in the repeater 220, the gain for amplification has a limit value. Therefore, the maximum gain limit value G _max changed by the gain limit value setting unit 2210 also has a limit value. Accordingly, the gain limit value setting unit 2210 controls the gain limit value not to be increased any more by the gain control value ΔG when the repeater 220 has a preset maximum gain by the set maximum gain limit value. Perform the function. In addition, when the repeater 220 has a preset minimum gain, a function of controlling the gain limit value may not be further reduced by the gain control value ΔG.

3 is a flowchart illustrating a gain adjusting method in a repeater according to an embodiment of the present invention.

First, the operator of the repeater inputs a setting value X _th for limiting the cancel value through the input unit 2212. The input erase value limit setting value is stored in the memory unit 2214 (S302).

The receiver 2202 of the repeater with the erase limit value set therein measures the input signal received through the receiving antenna 210 and transmits the measured input signal to the isolation calculation unit 2210 at a predetermined time interval. .

The isolation calculation unit 2210 calculates the isolation at the repeater from the input signal received from the reception unit 2202 (S304), and temporarily stores the calculated isolation in the memory unit 2214 (S306).

The I _means calculating unit 2218 calls an Isolation value stored in the memory unit 2214 on a predetermined time basis (S308), and calculates I _means by averaging the called Isolation values (S310).

When I _means is calculated in I _means calculating section 2218, gain estimate calculation unit 2220 in the call set stored in the calculated I _means a memory unit 2214 the value (X _th), and equation (1) Accordingly, the two values are summed to calculate an instantaneous maximum gain estimate G _means (S312).

When the G _means is calculated in the gain estimation calculator 2220, the calculated G _means is transferred to the comparator 2222. The comparison unit 2222 compares the transferred G _means with the size of G _max stored in the memory unit 2214 (S314).

As a result of comparing the magnitudes of G _means and G _max in the comparison unit 2222, when it is determined that the magnitudes of G _means and G _max are the same (S316), the gain control value calculating unit 2224 sets the gain control value ΔG to 0. It is set to (S318).

However, as a result of comparing the magnitudes of G _means and G _max in the comparison unit 2222, and it is determined that G _means is larger than G _max (S320), the gain control value calculation unit 2224 sets the gain control value ΔG to 1. It is set (S322). However, if it is determined that G _means is smaller than G _max , the gain control value calculator 2224 sets the gain control value ΔG to −1.

Here, according to the result of the magnitude comparison between G _means and G _max , the gain control value may be set to various sizes without limiting the magnitude of the gain control value to 1 or −1 (S324).

When the gain control value is determined by the gain control value calculating unit 2224 in this manner, the gain limit value setting unit 2226 adds the determined gain control value to the set maximum gain limit value G _max (S326). .

The result value G _max ′ calculated according to the sum of the gain control value and the maximum gain limit value is set again as the maximum gain limit value, and accordingly, the maximum gain limit value is adjusted (S328).

Here, according to the gain control value calculated by the gain control value calculator 2224, steps S326 and S328 for updating the maximum gain limit value may be represented by Equations 2 and 3 below.

G _max '= G _max + △ G

G _max '' → G _max

G _max (n + 1) = G _max (n) + ΔG

In this manner, the repeater can perform stable gain control according to the change of isolation in the mobile communication environment.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a configuration diagram briefly showing the structure of a wireless repeater;

2 is a block diagram schematically showing the internal configuration of the repeater according to the embodiment of the present invention;

3 is a flowchart illustrating a gain adjusting method in a repeater according to an embodiment of the present invention.

Claims (15)

In the method of adjusting the gain of the wireless repeater, (a) measuring isolation from the received signal; (b) calculating a gain estimate using the measurement result of the isolation; (c) determining a gain control value by comparing a magnitude of the gain estimate and a gain limit value set in the wireless repeater, wherein the gain limit value is a value for adjusting a gain in the wireless repeater; And (d) adjusting the gain limit value set in the wireless repeater using the gain control value Gain control method comprising a. The method of claim 1, Prior to step (a) above, Receiving and storing a setting value for limiting a cancel value in a feedback cancellation filter from an operator of the wireless repeater; Gain control method further comprising. The method according to claim 1 or 2, Step (a) is, (a1) measuring and storing the isolation at a predetermined predetermined time unit; And (a2) calculating an average value by calling one or more isolations stored at preset time intervals; Gain control method comprising a. The method of claim 3, Step (b) is, And calculating the gain estimate by summing the average value of the isolation and the set value. The method of claim 1, Step (c) is, The gain control value is determined to be '0' when the gain estimate is equal to the gain limit value, and when the gain estimate is greater than the gain limit value, the gain control value is determined as a preset positive value, and the gain And if the estimate is less than the gain limit, determining the gain control value as a preset negative value. The method of claim 1, Step (d) is, And adding the gain control value to a gain limit value set in the wireless repeater to update the gain limit value. The method of claim 6, Step (d) is, If the repeater has gain by the gain limit value set in the wireless repeater, the gain limit value is set so as not to increase any more by the gain control value, and the repeater is set by the gain limit value set in the radio repeater. If the has the lowest gain, the gain control method characterized in that the gain control value is set so that it is no longer reduced. In the wireless repeater for adjusting the gain according to the change of the isolation (Isolation), An isolation calculator for measuring isolation from an input signal received through the receiving antenna of the wireless repeater; A gain estimate calculator for calculating a gain estimate using the isolation calculated by the isolation calculator; A gain limit setting unit configured to perform gain control in the wireless repeater using the set gain limit value; And A gain control value calculator for calculating a gain control value for changing the gain limit value according to a comparison result between the gain limit value set in the gain limit value setting unit and the gain estimate calculated by the gain estimate value calculating unit; Wireless repeater comprising a. The method of claim 8, The gain limit value setting unit, And after receiving the gain control value calculated by the gain control value calculating unit, adding the gain control value to the gain control value and updating the gain limit value for adjusting the gain of the wireless repeater. 10. The method according to claim 8 or 9, Isolation average value calculation unit for calculating an average value for one or more isolation calculated by the isolation calculation unit in a predetermined predetermined time unit Wireless repeater further comprising. The method of claim 10, The gain estimate calculation unit, The gain estimation value is calculated by using a cancellation limit value set in advance by the operator of the wireless repeater to cancel cancellation in a feedback cancellation filter and an average value of the isolation calculated by the isolation average value calculation unit. Wireless repeater, characterized in that. The method of claim 11, The gain estimate calculation unit, And adding the average value of the isolation and the cancellation limit value to calculate the gain estimate. The method of claim 11, Input unit for receiving the erase limit setting value from the operator of the wireless repeater Wireless repeater further comprising. The method of claim 8, A comparison unit for comparing the gain limit value set in the gain limit value setting unit with the magnitude of the gain estimate calculated in the gain estimation value calculating unit and transferring a comparison result to the gain control value calculating unit Wireless repeater further comprising. The method of claim 14, The gain control value calculation unit, When the result of receiving the same result of the gain limit value and the gain estimate from the comparator, a gain control value having a magnitude of '0' is calculated, If a result of the magnitude of the gain estimate is greater than the gain limit value is received, a gain control value having a positive magnitude is calculated. And a gain control value having a negative magnitude is calculated upon receiving a result having a smaller magnitude of the gain estimate than the gain limit value.

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