阅读说明：本技术 一种基站天线 (Base station antenna ) 是由 希马斯.普利亚安达 胡中皓 井文才 唐亚丁 王金菊 于 2019-10-22 设计创作，主要内容包括：本发明揭示了一种基站天线,包括移相器、智能偏置器、天线阵列及滤波电路,滤波电路与天线阵列边缘的天线振子电连接,其包括滤波器,滤波器的输入端耦合至移相器两端的输出端中的任意一个,输出端与智能偏置器耦合,用于提取AISG信号和DC信号输送至智能偏置器。本发明通过使滤波电路与位于天线阵列边缘的天线振子电连接,并使滤波器从移相器两端的输出端中的任意一个提取AISG信号和DC信号,可有效解决PIM、RF信号的插入损耗和回波损耗,及天线阵列性能等问题。(The invention discloses a base station antenna, which comprises a phase shifter, an intelligent biaser, an antenna array and a filter circuit, wherein the filter circuit is electrically connected with an antenna oscillator at the edge of the antenna array and comprises a filter, the input end of the filter is coupled to any one of the output ends at two ends of the phase shifter, and the output end of the filter is coupled with the intelligent biaser and is used for extracting AISG signals and DC signals and transmitting the AISG signals and the DC signals to the intelligent biaser. The filter circuit is electrically connected with the antenna oscillator positioned at the edge of the antenna array, and the filter extracts the AISG signal and the DC signal from any one of the output ends at two ends of the phase shifter, so that the problems of insertion loss and return loss of PIM and RF signals, antenna array performance and the like can be effectively solved.)

1. A base station antenna, comprising

An intelligent biaser;

an antenna array comprising a plurality of antenna elements;

a phase shifter having a plurality of output terminals, each output terminal coupled to at least one antenna element;

and the filter circuit comprises a first filter, the input end of the first filter is coupled to any one of the output ends at two ends of the phase shifter, the output end of the first filter is coupled with the intelligent biaser, and the output ends at two ends have weaker power relative to the other output ends.

2. The base station antenna of claim 1, wherein the filter circuit is electrically connected to the antenna elements at the edges of the antenna array.

3. The base station antenna of claim 1, wherein the signals entering the first filter comprise an AISG signal, a DC signal, and an RF signal, and wherein the first filter is configured to filter the RF signal.

4. The base station antenna of claim 1, further comprising a power divider, wherein at least two antenna elements of the antenna array are coupled to an output of the phase shifter through the power divider.

5. The base station antenna of claim 1, wherein the filtering circuit further comprises an electrophoretic discharger and a matching circuit for matching the AISG signal, the matching circuit having an input coupled to the first filter through the electrophoretic discharger and an output coupled to the intelligent biaser.

6. The base station antenna of claim 5, wherein the matching circuit comprises a first capacitor, a second capacitor and an inductor, wherein one end of the first capacitor is electrically connected to the intelligent bias to form a first node, the opposite end is grounded through the inductor, one end of the electrophoretic discharger is electrically connected to the output end of the first filter to form a second node electrically connected to the first node, the opposite end is grounded, one end of the second capacitor is electrically connected between the first node and the second node, and the opposite end is grounded.

7. The base station antenna of claim 5, wherein the filtering circuit further comprises a second filter for enhancing filtering efficiency, the second filter coupled between the first filter and an electrophoretic discharger.

8. The base station antenna of claim 1, wherein the smart bias comprises a remote electrical tilt module that provides electrical tilt functionality to the antenna and a motor that controls antenna downtilt angle.

9. The base station antenna of claim 8, wherein the remote electrical tilt module comprises a modulator module configured to modulate the AISG signal to control the motor and a power module configured to provide power to the motor based on the DC signal.

10. The base station antenna according to claim 1, further comprising a circuit board provided with a feeding network, said filter circuit being integrated on said circuit board together with the feeding network.

11. The base station antenna of claim 10, further comprising a reflector plate, at least one of the antenna elements being soldered to the circuit board, the antenna element being mounted on the reflector plate together with the circuit board.

Technical Field

The invention relates to the technical field of mobile communication, in particular to a base station antenna.

Background

Smart Bias Stations (SBTs) are often used in base station antennas to allow AISG (Antenna Interface Standards Group) and DC (Direct Current) signals to be transmitted through RF (Radio Frequency) ports without using other AISG ports. When the intelligent biaser is integrated into a base station antenna, the intelligent biaser needs to be electrically connected to a Remote Electrical Tilt (RET) module, which can provide Remote Electrical Tilt function for the antenna to allow the Tilt angle to be tilted downward, and needs to add a filter in the antenna feed network to filter out the rf signal and further feed the AISG signal and the DC signal into the intelligent biaser.

However, improper filter placement is prone to cause several effects, such as RF signal insertion loss and return loss, PIM (passive inter-Modulation) problems, high filter isolation requirements, space occupation, and so on. As disclosed in international publication WO 2016022182a1, a multi-INPUT SMART BIAS (multi-INPUT SMART BIAS TEE) is disclosed, wherein a filter is located at the front end of a feed network and at a high power position, so that the possibility of PIM problem is high, the requirement on the isolation of the filter is high, the influence on the performance of an antenna array is large, and the insertion loss and the return loss of an RF band are both large.

Additionally, in some other existing designs, the phase shifter uses a capacitively coupled RF port, which forces the DC signal to be extracted at a high power output through a filter before the phase shifter or before the capacitively coupled RF port, which can cause RF degradation and possibly passive intermodulation due to other solder joints in the high power path, and cause more loss and phase distortion, while requiring the use of a higher isolation filter;

in some other prior designs, the filter is integrated into the last output of the phase shifter under the same structure, which, while avoiding the radio frequency attenuation due to the filter, occupies a large area of the phase shifter PCB, and the filter occupies a portion that may involve a ground plane in a stripline configuration, which increases the raw material cost of the overall phase shifter, and the phase shifter occupies more space on the back of the reflector.

Disclosure of Invention

The present invention is directed to overcoming the deficiencies of the prior art and providing a base station antenna that has less impact on RF signal performance, PIM problems, cost, etc. when integrated with an intelligent biaser via a filter.

In order to achieve the purpose, the invention provides the following technical scheme: a base station antenna comprises

An intelligent biaser;

an antenna array comprising a plurality of antenna elements;

a phase shifter having a plurality of output terminals, each output terminal coupled to at least one antenna element;

and the filter circuit comprises a first filter, the input end of the first filter is coupled to any one of the output ends at two ends of the phase shifter, the output end of the first filter is coupled with the intelligent biaser, and the output ends at two ends have weaker power relative to the other output ends.

Preferably, the filter circuit is electrically connected to the antenna elements located at the edge of the antenna array.

Preferably, the signals entering the first filter include an AISG signal, a DC signal and an RF signal, and the first filter is configured to filter out the RF signal.

Preferably, the antenna further comprises a power divider, and at least two of the antenna elements are coupled to one output end of the phase shifter through the power divider.

Preferably, the filter circuit further comprises an electrophoretic discharger and a matching circuit for matching the AISG signal, an input of the matching circuit being coupled to the first filter through the electrophoretic discharger and an output being coupled to the intelligent biaser.

Preferably, the matching circuit includes a first capacitor, a second capacitor and an inductor, one end of the first capacitor is electrically connected to the intelligent bias device to form a first node, the opposite end is grounded through the inductor, one end of the electrophoretic discharger is electrically connected to the output end of the first filter to form a second node electrically connected to the first node, the opposite end is grounded, one end of the second capacitor is electrically connected between the first node and the second node, and the opposite end is grounded.

Preferably, the filter circuit further comprises a second filter for enhancing filtering efficiency, the second filter being coupled between the first filter and the electrophoretic discharger.

Preferably, the smart biaser includes a remote electrical tilt module that provides an electrical tilt function to the antenna and a motor that controls the antenna down tilt angle.

Preferably, the remote electrical tilt module includes a modulator module for modulating the AISG signal to control the motor, and a power module for providing power to the motor according to the DC signal.

Preferably, the power supply circuit further comprises a circuit board provided with a feed network, and the filter circuit and the feed network are integrated on the circuit board

Preferably, the antenna further comprises a reflection plate, at least one antenna element is welded on the circuit board, and the antenna element and the circuit board are mounted on the reflection plate together.

The invention has the beneficial effects that:

(1) by electrically connecting the filter circuit to the antenna elements at the edges of the antenna array, the risk of Passive Intermodulation (PIM) is minimized.

(2) The filter is used for extracting the AISG signals and the DC signals and is coupled to any one of the output ends at two ends of the phase shifter, the output ends at the two ends are weaker than the power of other output ends, on one hand, the return loss and the insertion phase of the radio frequency signals can be reduced, the influence on the performance of the antenna array is reduced to the maximum extent, on the other hand, the power of the output ends at two ends of the phase shifter is lowered by a plurality of dB relative to the power of other output ends, the filter is enabled to easily reach the isolation specification of 40dB, and the isolation requirement of the filter is further relaxed.

(3) The filter circuit can be added only by modifying a single circuit board, so that the filter circuit is more convenient to add while the space is saved.

Drawings

FIG. 1 is a block diagram of a base station antenna structure according to an embodiment of the present invention;

FIG. 2 is a block diagram of a second base station antenna according to an embodiment of the present invention;

FIG. 3 is a block diagram of the circuit board of the integrated filter circuit of the present invention;

fig. 4 is a schematic circuit diagram of the matching circuit and the electrophoretic discharger of the present invention;

FIG. 5 is a circuit board schematic of an integrated filter circuit of the present invention;

fig. 6 is a block diagram of the intelligent biaser of the present invention.

Reference numerals: 10. the device comprises a first filter, 20, a matching circuit, 30, a second wave recorder, A, a first node, B, a second node, C1, a first capacitor, C2, a second capacitor, L, an inductor, D and an electrophoresis discharger.

Detailed Description

The technical solution of the embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention.

Referring to fig. 1 and 2, a base station antenna disclosed in the present invention includes an antenna array, a filter circuit, a phase shifter, and an intelligent bias device, wherein the antenna array includes a plurality of antenna elements arranged in an array, and the arrangement of the antenna elements may be set according to actual requirements; the phase shifter is provided with a plurality of output ends, in order to make the lobe width convergence of the wave beam better, the output ends at two ends of the phase shifter are weaker in power relative to other output ends, and each output end is coupled with at least one antenna element in the antenna array; the filter circuit is electrically connected with the antenna oscillator at the edge of the antenna array and comprises a first filter, the input end of the first filter is coupled with any one of the output ends at the two ends of the phase shifter, and the output end of the first filter is coupled with the intelligent biaser. In practice, the signals entering the first filter include an AISG signal, a DC signal and an RF signal, and the first filter is configured to filter the RF signal, that is, the first filter is configured to separate the AISG signal and the DC signal from the RF signal, and further output the AISG signal and the DC signal to an intelligent Bias unit (Smart Bias Tee, SBT).

In specific implementation, the AISG signal, the DC signal and the RF signal are input into the phase shifter through the RF port, the AISG signal, the DC signal and the RF signal are input into the first filter after being processed by the phase shifter, the first filter further filters the RF signal, and the AISG signal and the DC signal are output into the intelligent bias unit (SBT).

In this embodiment, the first filter is one of a low-pass filter, a band-pass filter, or a band-stop filter, and can be selected according to actual requirements during implementation.

The invention can reduce the risk of Passive Intermodulation (PIM) to the minimum by electrically connecting the filter circuit with the antenna elements at the edge of the antenna array, because the radiation at the edge of the antenna array is weaker.

In addition, the first filter extracts the AISG signal and the DC signal from any one of the output ends at two ends of the phase shifter, on one hand, the return loss and the insertion phase of the radio-frequency signal can be reduced, the influence on the performance of the antenna array is reduced to the maximum extent, on the other hand, the power of the output ends at two ends of the phase shifter is lowered by a few dB relative to the power of other output ends, so that the first filter easily reaches a preset isolation specification, such as a 40dB isolation specification, and the isolation requirement of the first filter is further relaxed.

As shown in fig. 1 and fig. 2, the coupling manner of each output end of the phase shifter with the antenna element includes various manners, in fig. 1, each output end of the phase shifter is directly coupled with one antenna element; in fig. 2, each output end of the phase shifter is coupled to at least two antenna elements through a power divider, and in specific implementation, the number of the antenna elements coupled to each output end of the phase shifter may be set according to actual requirements.

As shown in fig. 3, the filter circuit further includes an electrophoresis discharger D and a matching circuit 20, wherein an input terminal of the electrophoresis discharger D is coupled to an output terminal of the first filter 10, an output terminal of the electrophoresis discharger D is coupled to an input terminal of the matching circuit 20, an output terminal of the matching circuit 20 is coupled to the intelligent biaser, the electrophoresis discharger D is used for limiting transient overvoltage and discharging surge current, and the matching circuit 20 is used for matching 2-2.3 MHz AISG signals.

Specifically, as shown in fig. 4, the matching circuit 20 includes a first capacitor C1, a second capacitor C2 and an inductor L, wherein one end of the first capacitor C1 is electrically connected to the intelligent bias to form a first node a, and the opposite end is grounded through the inductor L; one end of the electrophoretic discharger D is electrically connected to the output end of the first filter 10, forming a second node B, and the opposite end is grounded, and the second capacitor C2 is designed to further prevent the passage of Radio Frequency (RF) signals; the first node A and the second node B are electrically connected; one end of the second capacitor C2 is electrically connected between the first node a and the second node B, and the opposite end is grounded, and the first capacitor C1, the second capacitor C2, and the electrophoretic discharger have a common ground terminal.

Further, in order to enhance the filtering efficiency, a second filter 30 is further provided in the filtering circuit, and as shown in fig. 5, the second filter 30 is coupled between the first filter 10 and the electrophoretic discharger D. The second filter 30 can also select one of a low-pass filter, a band-pass filter or a band-stop filter, which can be selected according to actual requirements.

Further, fig. 5 is a layout diagram of the filter circuit on a circuit board, where the circuit board is provided with a feeding network, and the filter circuit and the feeding network are integrated on the circuit board. As can be further seen from fig. 5, one path of the signal output by the phase shifter is directly coupled to the antenna element 40, and the other path of the signal is directly coupled to the filter circuit, and the first filter 10, the second filter 30, the electrophoresis discharger D, and the matching circuit 20 in the filter circuit are all integrated on one circuit board.

Further, the base station antenna further comprises a reflecting plate, the circuit board and the antenna oscillators are mounted on the reflecting plate together, at least one antenna oscillator is welded on the circuit board, and during implementation, the number of the antenna oscillators can be set according to actual requirements.

As shown in fig. 6, the smart biaser includes a remote electrical tilt module for providing an electrical tilt function to the antenna and a motor for controlling the antenna downtilt angle. Further, the remote electric tilting module comprises a modulator module and a power supply module, wherein the modulator module is used for demodulating AISG signals of 2-2.3 MHz to control the motor; the power module provides power to the motor according to the DC signal. When the antenna is implemented, the modulator module controls the motor to execute actions after AISG signal processing, and the downward inclination angle of the antenna is adjusted.

The filter circuit is arranged at the edge position of the antenna array, so that the distance from the intelligent biaser to the filter circuit is shortest, and interconnection can be easily realized.

Therefore, the scope of the present invention should not be limited to the disclosure of the embodiments, but includes various alternatives and modifications without departing from the scope of the present invention, which is defined by the claims of the present patent application.