CN1332175C - Apparatus and method for detecting electronic declination angle of communication antenna - Google Patents

Abstract

The present invention relates to a detecting device for an electric declinational angle of a communication antenna, which comprises a motor driving device (1), a phase shifter (2) and a regulation resistance (3). The moving end of the regulation resistance (3) is mechanically connected with a displaceable part of the phase shifter (2), and the motor driving device (1) drives the phase shifter (2) and the regulation resistance (3) to move synchronously. The present invention also relates to a detecting method for the electric declinational angle of the communication antenna, and the detecting device for the electric declinational angle of the communication antenna of the present invention has the advantages of simple structure and low cost, and can achieve the closed-loop control that the antenna is electrically adjusted; the detecting method for the electric declinational angle of the communication antenna of the present invention for achieving the closed-loop control that the antenna is electrically adjusted has the advantage of simple method, and the stepping precision can reach a 0.1 DEG stepping standard of an AISG conventional rule.

Description

Device and method for detecting electric downtilt angle of communication antenna

Technical field

The invention relates to a detection device for the electric downtilt angle of the electric adjustment antenna of a mobile communication base station, and also relates to a detection method using the detection device for the electric downtilt angle of the communication antenna.

Background technique

Plate-shaped base station antennas are widely used in the field of mobile communications, and the downtilt angle of the antenna determines the coverage area that the antenna beam points to. Antennas that use mechanical angle adjustment or fixed electrical downtilt have been difficult to meet the requirements of network optimization. The electronically adjustable antenna is very suitable for solving the problem of cross-area interference caused by dense users and small station distance in large and medium-sized cities, and it is very convenient to solve the problem of temporary traffic hotspots that often appear in urban areas. In communication network optimization: reduce the types and types of antennas that need to be manufactured; simplify on-site planning and reduce the cost of on-site construction in the community. Because the electronic downtilt can be adjusted by wire at the bottom of the tower, or remotely operated away from the site, it can also be managed in a unified and centralized control network in a city.

The applicant is Andrew Company of the United States, the application number is 02118421.6, the publication number is CN1492539A, and the Chinese patent titled "antenna control system" discloses an antenna control system capable of remotely changing the tilt of the antenna beam. The driving device continuously adjusts the phase shifter of the feed distribution network connected to the radiating element, thereby continuously changing the tilt of the antenna beam, and the controller can remotely change the beam tilt of several antennas in the field. The displacement control of the phase shifter in this patent application is a semi-closed loop control mode.

The phase shifter of the electric antenna is a key component. There are many structural forms at present, but in essence it can be divided into two methods: changing the length of the microstrip line and changing the medium. Both include movable parts and are driven by a motor through a reducer. As for the displacement control of the phase shifter, due to the limitation of the antenna manufacturing cost, the products currently on the market are all open-loop control or semi-closed-loop control. When several antennas share a hand-held controller and turn them on, or the electronically adjustable antenna needs to be self-calibrated after it has been used for a long time, the motor will move back and forth throughout the whole process; the self-calibration process takes 2-4 minutes. If the antenna is working, self-calibration will inevitably lose signal. If you want the antenna to not require self-calibration, and the downtilt angle of the antenna can be known immediately after the motor is turned off and the power is turned off, closed-loop control must be implemented. In addition, during use, for open-loop control, even if the cable is disconnected, or the motor is stuck, or the transmission mechanism slips, the use will not be known, and the angle can still be adjusted. For semi-closed-loop control, it is also necessary to make the self-check and correction of the whole motor back and forth, so that a fault can be found. Argus' electronically tunable antenna is closed-loop controlled, with separate resistors lined up, the structure is complex, and the step accuracy is 0.25°, which does not meet the 0.1° step standard stipulated in the AISG agreement.

The problem of using a potentiometer to measure displacement in a communication antenna is not only the selection of the potentiometer, the connection of the transmission mechanism, and the design of the fixed mechanical structure, but also the measurement of the output potential difference of the potentiometer. In the outdoor electromagnetic environment of big cities, there are various electromagnetic waves. Space electromagnetic induction makes the interference voltage on the transmission wire with a length of tens of meters reach tens of millivolts. How to eliminate the interference and detect DC on the order of several millivolts? Voltage variation, this is the implementation technique of the controller.

Contents of the invention

The technical problem to be solved by the present invention is to provide a low-cost detection device for electric downtilt angle of a communication antenna that realizes the closed-loop control of the electric adjustable antenna to improve the control performance of the antenna.

Another technical problem to be solved by the present invention is to provide a method for detecting the electrical downtilt angle of a communication antenna that uses the above detection device to realize the closed-loop control of the electrically adjustable antenna.

The present invention solves the technical scheme that its technical problem adopts:

A detection device for the electrical downtilt angle of a communication antenna, which includes: a motor drive device, a phase shifter, a potentiometer and a controller; the moving end of the potentiometer is mechanically connected to the displaceable part of the phase shifter, and the The motor driving device drives the phase shifter and the potentiometer to move synchronously, and adds a fixed voltage to the fixed end of the potentiometer. When the current flows through the potentiometer and the grounding resistor placed in the controller, a voltage is detected at the moving end of the potentiometer. The voltage that changes with the change of the position of the slave end, the voltage is converted into a digital value through a 10-bit analog-to-digital converter, and then processed by the controller calculation program to detect the electrical downtilt angle of the communication antenna.

The potentiometer is a rotary potentiometer, the motor drive device is a drive motor containing a reducer, and the gear on the shaft of the drive motor passes through the intermediate gear and the gear on the shaft of the phase shifter. Coupling, the gear on the shaft of the drive motor meshes with the gear on the shaft of the rotary potentiometer at the same time.

The whole movement time of the above-mentioned phase shifter is 1-2 minutes; no matter whether the potentiometer is multi-turn or single-turn, the corresponding control stroke is at least two-thirds of the full stroke of the potentiometer.

The potentiometer is a linear potentiometer, the motor drive device is a decelerated DC motor, the decelerated DC motor is installed on the support, the shaft of the decelerated DC motor is equipped with a lead screw, and the described lead screw It is threadedly connected with the slider for linear motion; the bracket is provided with a retaining ring, and the retaining ring is located at the end of the lead screw; the slider is connected to the other end of the push rod with a phase shifter at one end connection; the lower end of the slider can toggle the linear potentiometer at the same time.

A method for detecting the electrical downtilt angle of a communication antenna using the above-mentioned detection device, comprising the steps of:

(1) The detection device is installed on the mobile communication base station antenna;

(2) Measure the change of the resistance value between the moving end of the potentiometer and the other fixed end from R1 to R2, and at the same time, measure the electrical downtilt angle of the antenna from 0° when the phase shifter that moves synchronously with the potentiometer moves throughout the whole process Change to N°, and calculate the corresponding resistance change when the downtilt angle changes by 1° as (R2-R1)/N;

(3) Add a fixed voltage to the fixed end of the potentiometer, the current flows through the potentiometer and the grounding resistance placed in the controller, and a voltage that changes with the position of the moving end of the potentiometer is detected at the moving end; the voltage is passed through After the 10-bit analog-to-digital converter becomes digital, it is processed by the controller calculation program and restored to an amount that is linearly proportional to the change in resistance, and is also an amount that is linearly proportional to the angle change of the phase shifter. By multiplying it by a proportional coefficient The downtilt angle of the antenna can be calculated.

The potential difference at the output end of the potentiometer is detected in real time by a remote controller located in the base station equipment room.

Beneficial effects of the present invention:

The key technology for realizing the present invention is to use the potentiometer as the position detector for the displacement of the phase shifter to realize the full closed-loop control of the downtilt angle of the antenna and improve the overall control quality and performance.

Because the potentiometer is used in the present invention to realize the full closed-loop control of the electrical downtilt angle of the antenna, the self-checking and correcting process of the motor's full reciprocating motion necessary for the open-loop or semi-closed-loop control mode is omitted.

Due to the use of linear potentiometers in mobile communication base station antennas, mechanical failures of connecting cables and motors can be judged.

The invention adopts a potentiometer to detect the position, has a simple structure, and the step accuracy can reach the 0.1° step standard stipulated in the AISG agreement.

The invention is configured with a remote controller, allowing the electrical downtilt angle of the antenna to be changed through simple operations without stopping the machine. This method not only saves the operator from the fatigue of climbing the antenna tower, but also avoids the trouble of climbing stairs in the city.

The design of the present invention can also consider convenience for users and provide a perfect and friendly interface. In the central control room, the operator can select the base station by clicking the mouse on the electronic map, which is convenient and simple to query the downtilt angle of each antenna or change the downtilt angle of the antenna. The output form of the information is intuitive and eye-catching, and the coverage area of the antenna can be seen on the map. When the control failure of the antenna occurs, there will be an automatic prompt.

Description of drawings

Fig. 1 is the structural diagram when the present invention adopts rotary potentiometer;

Fig. 2 is a structural diagram when the linear potentiometer is used in the present invention, and the end of the push rod is connected to a phase shifter.

In the figure, 1 is a motor drive device, 2 is a phase shifter, 3 is a potentiometer, 11, 12, 13, 14 are gears, 22 is a bracket, 23 is a lead screw, 24 is a slider, 25 is a retaining ring, 27 for the putter.

Detailed ways

As shown in Figure 1, a detection device for the electrical downtilt angle of a communication antenna uses a rotary potentiometer, the motor drive device 1 is a drive motor containing a reducer, and the potentiometer 3 is a rotary potentiometer , the gear 12 on the rotating shaft of the driving motor is coupled with the gear 14 mounted on the rotating shaft of the phase shifter 2 through the intermediate gear 13, and the gear 12 on the rotating shaft of the driving motor is simultaneously connected with the rotating potentiometer The gear 11 meshes on the rotating shaft.

The driving motor including the reducer drives the gear 12 to rotate; the gear 12 is coupled through the intermediate gear 13 to drive the gear 14; and the gear 14 drives the phase shifter 2 to rotate. The gear 12 drives the potentiometer 3 to rotate through the gear 11 at the same time. When designing the transmission system, pay attention to make the full movement time of the phase shifter be 1-2 minutes; whether the potentiometer is multi-turn or single-turn, the corresponding control stroke is at least two-thirds of the full stroke of the potentiometer.

As shown in Figure 2, a detection device for the electrical downtilt angle of a communication antenna uses a linear potentiometer, the motor drive device 1 is a deceleration DC motor, the potentiometer 3 is a linear potentiometer, and the The decelerated DC motor is installed on the support 22, the rotating shaft of the decelerated DC motor is equipped with a lead screw 23, and the described lead screw 23 is threadedly connected with the slide block 24 for linear motion; the described support 22 is provided with a Stop ring 25, said stop ring 25 is positioned at the end of lead screw 23; Described slide block 24 is connected with the other end of push rod 27 that one end is connected with phase shifter 2; Described slide block 24 lower end can dial simultaneously Move the linear potentiometer 3.

The decelerating DC motor 1 drives the lead screw 23 to rotate, and the lead screw 23 drives the slider 24 to move linearly; the retaining ring 25 limits the axial displacement of the end of the lead screw 23 . The slider 24 drives the push rod 27 to move the phase shifter 2 . The sliding full movement time of the lower end of the slider 24 while toggling the linear potentiometer 3 is 1-2 minutes. The corresponding control stroke is at least two-thirds of the full stroke of the potentiometer.

A method for detecting the electrical downtilt angle of a communication antenna using the above-mentioned detection device, wherein a potentiometer, a phase shifter and a motor drive device are installed in the mobile communication base station antenna, and connected according to the above-mentioned detection device;

Set the resistance value between the movable end of the potentiometer and the other fixed end to change from R1 to R2 when the moving end of the potentiometer moves throughout the whole process, and set the electrical downtilt angle of the antenna to change from 0 to N degrees when the phase shifter moves throughout the entire process. Then (R2-R1)/N is the corresponding resistance change amount when the downtilt angle changes by 1°, which changes in a linear ratio. Add a fixed voltage to the fixed end of the potentiometer. When the current flows through the potentiometer and the grounding resistor placed in the controller, a voltage that changes with the position of the moving end can be detected at the moving end. Because there is current passing through, so The actual output voltage and the resistance value are not proportional to a straight line, but change according to the law close to the hyperbola. This voltage is converted into a digital value through a 10-bit analog-to-digital converter (A/D), and then processed by the controller calculation program to restore it to a linearly changing quantity; this linear quantity corresponds to the resistance value in proportion, and also corresponds to the phase shift in proportion angle of the device. Just multiply it by a proportional factor to convert it into the downtilt angle of the antenna.

During closed-loop control, compare the command angle with the current detection angle to determine the direction of rotation of the drive motor, and turn off the motor when it reaches the specified position (angle).

If the moving end of the potentiometer moves to the set value of R1 or R2, that is, it reaches the boundary of the phase shifting range of the phase shifter; when the controller detects that the angle is at the upper and lower limit values, it will turn off the motor in one direction to protect the mechanical transmission part unharmed.

If the resistance of the controller detection potentiometer is extremely high, it can be determined that the cable connecting the antenna to the controller is broken or not plugged into the socket. If the resistance of the detection potentiometer is extremely small, it can be determined that the cable has a short circuit. If the detection antenna angle does not change when the motor is rotated, it can be determined that the transmission system is faulty.

Claims (6)

1, a kind of detection device of communication antenna electrical downtilt angle is characterized in that: it comprises: motor drive unit (1), phase shifter (2), potentiometer (3) and controller; Described potentiometer ( 3) The moving end is mechanically connected with the displaceable part of the phase shifter (2), and the motor driving device (1) drives the phase shifter (2) and the potentiometer (3) to move synchronously, and fixes the potentiometer (3) When the current flows through the potentiometer (3) and the grounding resistance placed in the controller, a voltage that changes with the position of the moving end of the potentiometer (3) is detected at the moving end of the potentiometer (3). The voltage passes through a 10-bit analog-to-digital converter, becomes digital, and then is processed by the controller calculation program to detect the electrical downtilt angle of the communication antenna. 2. The detection device for the electric downtilt angle of the communication antenna according to claim 1, characterized in that: the potentiometer (3) is a rotary potentiometer, and the motor drive device (1) is a Drive motor, the gear (12) on the rotating shaft of the driving motor is coupled with the gear (14) mounted on the rotating shaft of the phase shifter (2) through the intermediate gear (13), the rotating shaft of the driving motor Gear (12) meshes with the gear (11) that is contained on the rotary potentiometer (3) rotating shaft simultaneously. 3. The detection device for the electrical downtilt angle of the communication antenna according to claim 2, characterized in that: the full movement time of the phase shifter (2) is 1-2 minutes; Whether it is multi-turn or single-turn, the corresponding control stroke is at least two-thirds of the full stroke of the potentiometer (3). 4. The detection device for the electric downtilt angle of the communication antenna according to claim 1, characterized in that: the potentiometer (3) is a linear potentiometer, and the motor driving device (1) is a geared DC motor, The decelerated DC motor is installed on the support (22), the rotating shaft of the decelerated DC motor is equipped with a lead screw (23), and the described lead screw (23) is threadedly connected with the slide block (24) for linear motion. ; Described support (22) is provided with a retaining ring (25), and described retaining ring (25) is positioned at the end of leading screw (23); Described slide block (24) is connected with a phase shifter (2) The other end of the push rod (27) is connected; the lower end of the slide block (24) can toggle the linear potentiometer (3) simultaneously. 5. A method for detecting the electrical downtilt angle of a communication antenna using any one of the detection device of claims 1-4, characterized in that it comprises the following steps: (1) The detection device is installed on the mobile communication base station antenna; (2) Measure the resistance value change from R1 to R2 between the moving end of the potentiometer and the other fixed end when the moving end of the potentiometer moves throughout the whole process. ° to N°, and calculate the corresponding resistance change for every 1° change in the downtilt angle as (R2-R1)/N; (3) Add a fixed voltage to the fixed end of the potentiometer, the current flows through the potentiometer and the grounding resistance placed in the controller, and a voltage that changes with the position of the moving end of the potentiometer is detected at the moving end; the voltage is passed through After the 10-bit analog-to-digital converter becomes digital, it is processed by the controller calculation program and restored to an amount that is linearly proportional to the change in resistance, and is also an amount that is linearly proportional to the angle change of the phase shifter. By multiplying it by a proportional coefficient, the The downtilt angle of the antenna can be calculated. 6. The method for detecting the electrical downtilt angle of the communication antenna according to claim 5, characterized in that: the potential difference at the output end of the potentiometer is detected in real time by a remote controller located in the base station equipment room.

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