KR20220107450A - Method for automatic restoration and control of angle and tilt of wireless base station antenna - Google Patents

Abstract

The present invention relates to a method for automatically recovering and controlling an antenna direction of a wireless communication base station, and more particularly, to a device and method for monitoring an angle and a tilt of an antenna in remote, automatically performing restoration-to-original state, and controlling a precise direction. The device of the present invention comprises: a means for installing an inertial measurement device for monitoring an angle and a tilt (hereinafter, referred to as "direction") in real time in a wireless communication base station antenna, and collecting data from a remote location; a data processing means for calculating the angle and the tilt of the antenna using the collected data; a means for restoring a direction of the antenna to an original state when being changed; and a means for precisely controlling the direction of the antenna from a remote location. Therefore, a wireless network can be efficiently operated.

Description

{Method for automatic restoration and control of angle and tilt of wireless base station antenna}

The present invention relates to an apparatus and method capable of real-time monitoring of an angle and tilt (hereinafter referred to as "direction") of an antenna of a wireless communication base station and capable of automatic recovery and control when an abnormality occurs. It monitors in real time the phenomenon that the direction of the antenna is changed due to factors inside and outside the device such as wind, vibration, earthquake, etc. It relates to a method for quickly securing reliability through service quality improvement, and in addition, it has a function to automatically restore to its original position when there is an unwanted direction change in the antenna, and a function to adjust the position remotely is additionally provided. It is about a system with

The present invention relates to a sensor and a control device that remotely monitors the direction of a wireless communication base station antenna and automatically recovers when the direction is changed. In particular, an inertial measurement unit (IMU) is used to monitor the direction of the antenna in real time, and an abnormality is found. It is a system that notifies the operator in real time and automatically restores the original state in case of an accident, and it relates to a system with a function to control the antenna remotely. In the case of a system that provides high-speed data such as 5G, advanced technologies such as beamforming are used, which is a fact that the performance of the antenna has a huge impact on the quality. You must adjust the orientation in real time to achieve maximum performance. Therefore, when it is necessary to adjust the direction to a degree that is impossible with the beamforming technology, it is necessary to adjust the direction of the antenna remotely.

Due to the generalization of smartphones and the rapid development of microelectromechanical systems (MEMS), the size of the sensor has been reduced and the price of the sensor, which was previously expensive, has become remarkably low and is being used in many fields. In particular, the Inertial Measurement Unit (IMU) is used in all smartphones and widely used in many IoT fields such as drones, making it possible to use it at an economical price.

IMU (Inertial Measurement Unit) is an inertial measurement device, and it also refers to a device composed of a gyroscope (hereinafter, “gyro”), an accelerometer, and a geomagnetic sensor. In the inertial measurement device, each sensor measures its own physical quantity, and if we briefly describe the measurable physical quantity for each sensor; The gyro sensor is used when it is necessary to measure the angular velocity (rad/s), that is, how many degrees per hour it rotates. The accelerometer measures the acceleration (m/s ² ) and uses it to measure the tilt by decomposing the gravitational acceleration when calculating the initial value. In addition, the speed and distance traveled can also be used by integrating the acceleration. The geomagnetic sensor measures the magnetism and measures the intensity of the flux of magnetic force based on magnetic north to measure how far it is deflected based on magnetic north.

In practical use, since it is impossible for each sensor to ideally measure physical quantities without error, the strengths and weaknesses of each sensor must be identified and supplemented. First, the gyro sensor continuously measures the angular velocity, but there are integral errors and errors due to the rotation of the earth. On the other hand, the accelerometer measures values discontinuously and is relatively accurate because it responds faster than the gyro sensor. For this reason, in the actual field, various sensors are mixed and used. There are 6-axis (6 DoF; Degree of Freedom) and 9-axis inertial measurement sensors as the mainly used inertial measurement sensor devices. It means that a sensor is added. In the present invention, although a 6-axis inertial measurement device is intended to be used, a 9-axis or more inertial measurement sensor may be mixed and used depending on the field situation. Examples of the 9-axis or more sensor may include an inertial measurement device in which GPS, temperature, humidity, and pressure sensors are added as necessary in addition to the 9-axis sensor.

The above-described inertial measurement device can be said to be a kind of sensor fusion, and the method of sensor fusion is sensor-unit fusion, processor-centered fusion, fusion through artificial intelligence (AI) and software advancement, and between specialized companies in each field. Convergence through omnidirectional integration reinforcement is an example.

Existing patents are limited to remotely controlling the direction of the antenna or controlling the direction by using radio wave characteristics, but the present invention monitors the direction of the antenna in real time using a sensor and automatically restores when an abnormality is found. Not only can it be done, but how it can be adjusted remotely if necessary.

KR10-1482650-0000 B1 base station antenna angle measuring device and method KR10-0328442-0000 B1 base station antenna direction control device KR10-1100688-0000 B1 A repeater with adjustable antenna direction and cell optimization method KR10-0924245-0000 System and method for automatically determining and calibrating the bearing and elevation direction of the B1 directional antenna"

An object of the present invention is to solve the conventional problems as described above, in particular, by collecting data of an inertial measurement unit (IMU) provided in a base station antenna in real time from a remote location, monitoring the direction of the antenna in real time, and detecting anomalies The goal is to minimize the time for radio wave quality degradation due to time delay caused by the dispatch of specialized personnel by automatically restoring the system to its original state, and at the same time to reduce the labor cost to manage the system cost-effectively.

As described in the technology behind the invention (design), an inertial measurement unit (IMU) is attached to an antenna to measure the gyro, acceleration and geomagnetism, and the measured physical quantity is transmitted to a remote location through wired/wireless communication. The remote management center calculates and monitors the angle and inclination of the antenna using the transmitted physical quantity, sets the level of warning according to the degree of change, and notifies the operator. In addition, after a warning is generated by comparing and analyzing the initial data of installation, the antenna direction is automatically adjusted to the original state using the linked motor. Additionally, if necessary, the antenna is remotely controlled from a remote location, and the result is identified in real time to enable accurate direction adjustment.

The present invention is to improve the above-described problems in the technology that is the background of the invention (design), and collects data of an inertial measurement unit (IMU) provided in a base station antenna in real time from a remote location to measure the direction and inclination angle of the antenna. Real-time monitoring enables immediate action to be taken when anomalies are found At the same time, it aims to manage the system cost-effectively by reducing the labor cost. In addition, when there is a change in the wireless environment due to a new building near the base station, etc., by adjusting the direction of the antenna at a remote location, it has the advantage of conveniently adjusting the radio wave characteristics of the wireless network and operating the wireless network efficiently.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the detailed description of the present invention to be described later. should not be construed as being limited only to
1 is an exemplary installation view for explaining the direction and inclination angle of a sector antenna that is typically installed;
2A and 2B are exemplary views for explaining the frequency characteristics and filter results for each sensor of the inertial measurement device;
Fig. 3 is a block diagram showing the functional configuration of the inertial measurement device;
4 is an exemplary view of an attachment position of an inertial measurement device according to a preferred embodiment of the present invention;
Figures 5a, 5b, 5c is an exemplary view of the attachment method of an external device for changing the direction of the base station antenna
6A and 6B are exemplary views of a method for attaching an antenna-embedded device for changing the direction of an antenna of a base station and an appearance of an antenna;
7 is a network configuration diagram according to a preferred embodiment for remote monitoring and automatic recovery of an external antenna direction of the present invention;
8 is a flowchart of a server program according to a preferred embodiment of the present invention;

The present invention relates to a sensor and a control device that remotely monitors the direction of a base station antenna and automatically recovers when the direction is changed. In particular, an inertial measurement unit (IMU) is used to monitor the direction of the antenna in real time, and when an abnormality is found It is a system that informs the operator in real time and automatically restores the direction, and additionally relates to a system with a function to control the antenna remotely.

Hereinafter, the advantages and features of the present invention, and a method of achieving them will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be embodied in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and those of ordinary skill in the art to which the present invention pertains. It is provided to fully inform the person of the scope of the invention, and the present invention is only defined by the scope of the claims.

1 is a conceptual diagram for the direction (Angle) and tilt (Tilt) of the antenna. The antenna 10 is connected to the antenna support bar 11 and the ground at a specific angle 12, and this angle is referred to as an inclination angle. Also, the direction 13 perpendicular to the front of the antenna is the direction in which the main beam of the antenna propagates. When the angle of the antenna is described with the H-plane (vertical) antenna radiation pattern on the right side of FIG. 1, it means the angle 14 formed by a line segment perpendicular to the front of the antenna with the direction of true north (or magnetic north). do.

2A and 2B show the accuracy of the acceleration sensor and the gyro sensor according to frequency. In the case of a gyro sensor, it is difficult to expect an accurate value due to a drift phenomenon in which a value changes in a low frequency region. In other words. The frequency characteristic 20 of the gyro sensor has low accuracy at low frequencies and high accuracy at high frequencies, whereas the frequency characteristic 21 of the acceleration sensor has high accuracy at low frequencies while decreasing accuracy at high frequencies.

A device that calculates 3D orientation by fusion of a gyro, geomagnetic and acceleration data is called an Attitude Heading Reference System (AHRS). With such sensor fusion, drift due to angular velocity integration is compensated using a reference vector, that is, gravity and earth magnetic field data to increase accuracy.

In general, as a method of processing raw data of an inertial sensor to obtain a stable value, various filters such as a complementary filter or a quaternion are used in addition to the Kalman filter. As an example of sensor fusion, in the case of a complementary filter, weights are calculated according to frequencies in consideration of the characteristics of each sensor, and as a result, the frequency characteristics 22 show a flat tendency.

Since the antenna of the wireless communication base station is usually installed in a high place where the visible distance is secured, minute vibrations are continuously generated under the influence of the wind, thereby increasing the probability of false alarms. In addition, noise caused by factors other than the movement of the antenna itself, electrical noise caused by PCB electronic components, errors of the sensor itself, and other background noise are mixed, so the raw data of the sensor (Raw data) ) is impossible to use as it is.

Therefore, in the present invention, it is necessary to distinguish between the noise caused by the fine vibration caused by the wind and the raw data including the noise listed above and the situation in which the antenna direction is actually changed. to use it. As an intuitive example, the raw data 26 through the sensor causes a lot of change due to the various factors described above, so it is impossible to use it by itself. ) can be seen to be very close to

Looking at the prior art literature, (Patent Document 0001) Republic of Korea Patent Registration No. 1003284420000 (2002.02.28) "Base station antenna direction control device" in the case of the antenna azimuth, the direct north direction measured outside the range of the antenna electromagnetic field using a motion recognition sensor. The present invention relates to an apparatus and method for measuring an angle of an antenna of a base station by measuring and measuring an angle of an antenna using a tilt sensor in the case of a tilting angle of an antenna, thereby making it easier to measure an angle of an antenna.

According to the method proposed here, the azimuth is to be measured using the true north direction angle and motion recognition sensor measured outside the range of the electromagnetic field. In fact, it is difficult, and in the case of a tilt angle, a tilt sensor is used, but the tilt sensor is a burdensome device in terms of price or power consumption.

On the contrary, in the present invention, since it is universally used in smartphones, the number of parts is reduced by using an accelerometer and an accelerometer, which is advantageous in terms of performance, price, and power consumption, and a filter that complements the characteristics of each element is applied to determine the antenna azimuth and There is a difference in that industrial applicability is increased by measuring the tilting angle remotely and in real time, and in addition, automatic recovery and remote control functions are added.

Fig. 3 is a block diagram showing the functional configuration of the inertial measurement device. The sensor unit 30 collects raw data using various sensors, such as a gyro, an acceleration, and a geomagnetic field. As described above, the raw data collected by the sensor unit 30 cannot be used as it is due to various noises, so the filter unit 31 removes the noise using a filter and selects and uses the best data. Control and calculation of the entire device is performed through the unit 32 , and the result is modulated for wired or wireless communication through the communication unit 33 and outputted to the outside through the wireless antenna 34 or the wired interface 35 . do. A memory 36 is built-in for various calculations or data storage, and a power supply unit 38 for supplying power to all parts is provided, and a storage battery for operation of the device can be built-in in an emergency. In the case of attaching the inertial measurement device to the outside of the antenna, the solar cell 39 is used so that the device can be operated without a separate external power supply. to use the external power matching unit 300 that converts the power to the power that the device can use.

4 shows a preferred example of the attachment position of the inertial measurement device. If the measured physical quantity is too small, false information may occur due to an error of the sensor itself or a minute vibration. In particular, in the case of the base station antenna 40, it is installed at a high place and has a down tilt. In addition, since most of the inclination is possible due to the influence of gravity, in this case, attaching the inertial measuring device to the upper part of the antenna 47 causes the greatest change in the physical quantity.

To explain the inclination case in more detail, when the antenna 40 indicated by a dotted line is installed at a right angle from the ground in the same direction as the antenna support rod 41 and is tilted at a certain angle to change to the antenna position indicated by a solid line, the upper In , it can be seen that the support rod 41 and the support rod 41 are spaced apart by a large distance 42, but are spaced apart by a small distance 43 in the lower part.

Similarly, when the angle of the antenna is changed, the physical quantity that changes is small (45) near the upper center point of the antenna, and the physical quantity changes significantly (44) at the corner, so in order to collect more discriminating data, Attaching an inertial measurement device to the

5a, 5b, and 5c are preferred exemplary views of a method of attaching an external device for changing the direction of the base station antenna. This is an installation method for a case where this device is added to an existing antenna to automatically monitor the direction of the antenna and to use it to automatically recover when an error occurs.

For example, when it is assumed that the antenna 50 is installed in a direction perpendicular to the ground as shown in FIG. 5A at first, that is, in the case where it is installed in parallel with the antenna support rod 51, the bolt 55 is configured with a nut. It serves to fix by giving an arbitrary angle between the steel plates (52). On the other hand, it serves to connect the steel plates, but in order to enable rotation, in part, stripper bolts 56 and 57 and nuts are used. Here, the stripper bolt 57 is connected to the motor 53 attached to the antenna support rod, and the connected screw or wire 54 is adjustable in length so that it is used to adjust the angle.

When the antenna installed as shown in FIG. 5A is changed as shown in FIG. 5B due to some factor, that is, the bolt 55 part, which should be fixed with a bolt and a nut, becomes loose, and the angle of the connection part increases as shown in 55-1. , a screw connected between the motor 53 and the stripper bolt 57 by using a motor to restore the original state, assuming that the angle of the part connected by the stripper bolts 56 and 57 is also increased as in 56-1 and 57-1, respectively. Or by winding the elongated line 54 to reduce the angle of the part connected by the stripper bolts 56 and 57 to 56-2 and 57-2, respectively, so that it is perpendicular to the ground (ie, parallel to the antenna support rod) as in the original shape. can be restored The above example exemplifies a case in which the antenna inclination is changed. When these devices are installed in a total of four places on the top, bottom, left and right, the angle of the antenna can also be controlled.

However, since the method described in this drawing is an example in which the direction of the antenna can be modified by using a triangular shape in order to maintain the posture of the antenna stably by dispersing the force, the direction can be controlled using other methods.

6A and 6B are exemplary views of a method of attaching an antenna-embedded device for changing the direction of an antenna of a base station and an appearance of an antenna. The antenna 60 is protected by the antenna exterior 61 for waterproofing and heat dissipation. Here, when the direction of the built-in antenna is viewed from the side in order to minimize the influence of external factors such as wind and minimize the surface area of the antenna appearance, the left side view has the same shape as 63 . The reason why the top and bottom is not symmetrical is that the weight of the antenna causes an error in the inclination to move downward, so more space for movement should be made in the lower part. The plan view has the same shape as 62 and adjusts the angle. Since the antenna has a screw 65 connected to the motor 64 whose length can be adjusted in a total of four places, the direction of the antenna can be adjusted according to the rotation direction of the screw. That is, in order to make the built-in antenna face upward, the hardness can be adjusted upward by pushing the built-in antenna outward using the lower screw and pulling the upper screw inward.

The antenna and the screw for direction adjustment are connected to the spherical female screw 66 inside the built-in antenna so that 360 degree rotation is possible. The spherical female screw is fixed by a 67-shaped cylindrical mechanism in 4 directions from the antenna body, and lubricating oil is used between this mechanism and the spherical female screw to allow free movement.

The built-in antenna has the advantage of being able to control the direction using a relatively small-capacity DC motor and parts because it is lighter than the external type. The above description is just one example of controlling the direction of the antenna, and it can be implemented in other ways.

7 is a network configuration diagram according to a preferred embodiment for remote monitoring and automatic recovery of an external antenna direction of the present invention. When the inertial measuring device 70 is attached to the exterior of the antenna and used, the data measured using the inertial measuring device is transmitted to the gateway 71 using wired/wireless communication, and the gateway is transmitted from several inertial measuring devices. Data is collected and transmitted to the mobile communication base station. This data is transmitted to the central server 74 through the Internet network, and the central server refers to the database and transmits an alarm or restore command in the opposite direction to the data collection path. do. All measurement data and alarm information are processed so that the user can operate and maintain, and are transmitted to the terminal device 76 and the mobile phone 77 .

8 shows a preferred server program flow chart according to an embodiment of the present invention. After collecting data from sensors such as gyro, acceleration, and geomagnetic field (80) and processing the collected data using the filter (81) to reduce noise and improve accuracy, it is checked whether the measured sensor value is above the allowable value. If it is determined (82) and is less than the allowable value, the measured value is accumulated with the existing value and recorded in the storage device (83), and it is checked whether the new accumulated value is above the allowable value (84), and if it is less than the allowable value, it is ignored (85), If it is more than the allowable value, an alarm is generated (86), and after initial restoration (88) with reference to the database 87 recorded at the time of initial installation, it is terminated (89). In this process, if the measured value is less than the allowable value, even though it is not currently necessary to generate an alarm and restore it, if the accumulated value is more than the allowable value, it is accumulated because it is necessary to restore it as an abnormal situation. When the value of the sensor measured after applying the filter (81) is greater than the allowable value (82), an alarm is generated (86), and the antenna direction is restored to its original state by referring to the database 87 recorded at the time of initial installation (87) After that, the process is terminated (89).

9 shows a preferred server program flow chart when the direction of the antenna is changed at a remote location according to an operator's need. First, the current direction data is collected (90), and the accuracy is increased by applying a filter to the collected data (91). Afterwards, when the operator inputs direction data to be corrected (92), the motor attached to the antenna terminal is operated to adjust the direction (93), and it is checked whether the changed direction matches the desired direction (94) and the modified direction If this direction is not the desired direction, adjustment is made by operating the boat again (95). If the direction is correctly adjusted through the above process, the adjusted data is stored in the database (96), the existing data is updated in the database (97), and the operation is terminated (98)

In general, in a wireless communication system, quality of service is greatly affected by power control between a base station and a mobile station, and an angle and tilt of a base station antenna. An antenna is installed to have a specific direction through a wireless network design at the initial stage of the base station installation. However, the direction of the antenna may be changed undesirably due to various factors such as rainstorm, vibration, earthquake, and aging of the bolt nut. there are many In particular, in systems that require high-speed data communication such as 5G, since the antenna and equipment are included in a single enclosure, the weight and size increase, and thus receive a lot of external influence. to be.

If we look at the current status of mobile telecommunication service providers, if there is a complaint report from a consumer from a specific base station, or when a special item occurs while monitoring service quality such as call success rate, handoff success rate, and call cut rate, the quality deteriorates, various base station-related parameters If the solution is not resolved after examining and applying the (Parameter), the expert staff manually adjusts the left and right angle and inclination of the base station antenna to improve the service quality. In other words, it is operated in the form of an after-service service, which is processed after an accident has occurred, and if measures are taken in this conventional way, a lot of time is required, which leads to consumer dissatisfaction and reduced reliability. In particular, the problem becomes more serious in areas where it is difficult for specialized personnel to dispatch, such as mountainous areas, island areas, and high iron towers. In addition, since these tasks are performed manually by humans, human error may occur, and there are limits to precise work. In addition, there was a problem of high-cost rescue because it requires a lot of resources, such as specialized personnel to manage a large number of base station antennas and vehicles for emergency dispatch. The present invention is a solution that can be applied to domestic as well as overseas operators because it is possible to maintain or improve the service quality of a wireless network and to reduce operating costs by improving the above-described problems.

S: Distance between transmission towers (span) T: Horizontal tension
W : Weight of wire R : Ear of overhead branch wire
d : Measured distance between sensor devices D : Distance between the vertical central axis of the transmission tower and the parallel line of the transmission line

Claims (5)

Measure the direction of the wireless communication antenna in real time, and if an abnormality is found,
sensors and devices that enable recovery to state;
a sensor device including the direction measuring sensor and a communication unit;
means for sending the data of the sensor device to a remote server;
When an antenna direction change situation is detected, the antenna direction is automatically restored using database information,
A method to accurately check and adjust the antenna direction from a remote location when necessary
Measure the direction of the antenna using a 9-axis or 6-axis inertial measurement device using a gyro and acceleration and geomagnetic sensor, and compare it with database information to determine the direction of the antenna using a motor and a stripper bolt when an abnormality is found. How to get it back to its original direction
According to claim 2,
By attaching a device for measuring the direction to the edge of the antenna element outside the antenna enclosure or inside the enclosure, the direction of the antenna is measured more precisely, and the physical measurements of each sensor are efficiently fused and utilized for accurate calculation of the direction of the antenna. The structure of the housing having a narrow upper part and a wide lower part when viewed from the antenna side to minimize errors and change the direction of the antenna element with a minimum volume
A communication unit for transmitting the measured value of the inertial measurement device to a base station or gateway, and a device having a function of supplying power using a solar cell (solar cell) for convenience of operation and maintenance
A method of accurately adjusting the direction by adjusting the direction of the antenna at a remote location and checking the adjusted result in real time at a remote location using a direction measuring device

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