A Hemispherical Antenna Beam Selection Method for 5G Communication

Abstract

The present application discloses a hemispherical antenna beam selection method for 5G communication, belonging to the field of antenna technology, including: constructing a 5G integrated base station module with m ports for the base station channels; constructing an antenna module; powering the 5G integrated base station module and the antenna module; the 5G integrated base station module identifies and reads the ID number of the antenna module to judge the antenna type; the control processor in the hemispherical antenna module ensures synchronization with the base station by acquiring the synchronization reference signal of the base station and provides a time reference for switch switching; the control processor drives the switch to switch through n paths in a loop to realize the connection of m*n sub-antennas; the beam selection method in the present application can achieve high gain of antennas in any direction of the hemispherical radiation surface; at the same time, the circuit complexity and cost in the present application are effectively compressed, and the applicable range is wider.

Description

Technical Field

[0001] This application belongs to the field of antenna technology. Specifically, it relates to a hemispherical antenna beam selection method for 5G communication. Background Art

[0002] In recent years, with the significant improvement of the payload capacity of drones, the gradual safety and stability of flight control hardware and algorithms, and the rapid development of 5G communication technology, there has been a demand for using drones to carry integrated base stations into the sky and achieve communication coverage for terminals within a radius of 10 kilometers on the ground in the fields of low-altitude economic development, emergency communication support, military, and the coverage of the next-generation 6G low-altitude base stations. According to the conversion of the air-ground communication scenario and the radio signal attenuation characteristics, for the lifted base station to achieve communication coverage for terminals within a radius of 10 kilometers, the base station antenna needs to achieve a hemispherical gain of 8 dBi. Therefore, an antenna beam selection method that can achieve a gain greater than 8 dBi in all directions of the hemispherical coverage and increase the airborne 5G communication coverage radius to more than 10 kilometers is particularly important. Summary of the Invention

[0003] To solve the above problems and technical deficiencies, the embodiments of this application adopt the following technical solutions. A hemispherical antenna beam selection method for 5G communication includes the following steps:

[0004] Step S1: Construct a 5G integrated base station module with m ports for the base station channels;

[0005] Step S2: Construct an antenna module;

[0006] Step S3: Power the 5G integrated base station module constructed in Step S1 and the antenna module in Step S2;

[0007] Step S4: The 5G integrated base station module identifies and reads the ID number of the antenna module, determines the antenna type based on the ID number. When it is identified and determined to be a hemispherical antenna, an algorithm program for driving the hemispherical antenna is triggered. When it is identified and determined to be a common antenna, a standard mode for cooperating with the common directional antenna is adopted;

[0008] Step S5: The time synchronization module in the 5G integrated base station module gives the synchronization reference signal of the base station to the control processor in the hemispherical antenna module to provide a time reference for the subsequent switch switching; the hemispherical antenna module ensures synchronization with the base station through time reference synchronization;

[0009] Step S6: The control processor in Step S5 drives the switch of each port to perform an n-way cyclic traversal to connect m * n sub-antennas.

[0010] Further, in Step S1, the constructed 5G integrated base station module integrates RRU, BBU, 5GC, and IMS core network.

[0011] Preferably, the hemispherical antenna module constructed in step S2 includes an antenna interface module, a radio frequency switch module, a clock synchronization circuit module, a sub-antenna module, a control processor module, and a power management circuit module;

[0012] The antenna interface module includes a radio frequency interface and a digital interface on the hemispherical top plane. The radio frequency interface is m SMA interfaces connected to the 5G integrated station through feeder lines; the digital interface is a serial port connected to the base station, receiving the 1pps time reference signal from the base station and transmitting back the antenna ID signal;

[0013] The radio frequency switch module includes m SPnT radio frequency switches, and each switch realizes the expansion of 1-way radio frequency transceiver into n-way radio frequency transceiver through switch control;

[0014] The clock synchronization circuit module includes a TCXO and a phase-locked loop circuit, which is responsible for receiving the 1pps time reference signal transmitted from the 5G integrated station, and completing the output of a new clock through the internal phase discrimination and frequency locking circuit to ensure the clock synchronization with the 5G signal clock;

[0015] The sub-antenna module is pasted on the spherical dielectric carrier board;

[0016] The control processor module is used to control the selection and switching of m switches, and control the dwell time and switching protection time of each switch from 1 to n channels;

[0017] The power management circuit module includes an on-board battery to supply power to the switches, TCXO, and phase-locked loop chips.

[0018] Furthermore, the sub-antenna module has 1 to L layers from top to bottom, and the horizontal 3dB beamwidth of the p-th layer sub-antenna module is The elevation 3dB beamwidth of all layer antenna modules is: Among them, , 1 ≤ p ≤ L, is the communication frequency, with the unit of MHz, and r is the radius of the hemispherical antenna, with the unit of meter.

[0019] Still further, the m*n sub-antenna modules have L layers from top to bottom, and the spacing between the array elements in each circle is 0.75λ, where λ is the wavelength corresponding to the center frequency.

[0020] Furthermore, after the antenna and the base station are synchronized, the control processor drives the switch to perform path switching. In the initial state, the first group of sub-antennas is selected, and then it is switched in sequence according to the sequence number of each group of sub-antennas and then returns to the initial state, cycling through;

[0021] The beam dwell time ≥ the transmission period of SSB;

[0022] During the switching process, the sub-antenna module number selected by the i-th switch is j + (i - 1) * n, where 1 ≤ i ≤ m and 1 ≤ j ≤ n.

[0023] Compared with the prior art, the beneficial effects of the embodiments of the present application are as follows:

[0024] The beam selection method in the present application can achieve an antenna gain greater than 8 dBi in any direction of the hemispherical radiation surface, enable the UAV base station to fly 500 - 5000 meters, and have a communication coverage radius greater than 10 kilometers for ground mobile phones. Moreover, there are no blind spots in the communication coverage when the UAV is in any flight attitude and the mobile phone is within a circle with a radius of 10 kilometers. At the same time, the circuit complexity and cost in the present application are effectively compressed, and the applicable range is wider. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In the drawings:

[0026] Figure 1 is a flowchart of an embodiment of the present application;

[0027] Figure 2 is a hardware block diagram of the hemispherical antenna in an embodiment of the present application;

[0028] Figure 3 is a distribution diagram of sub-antenna modules in an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of the division of sub-antenna coverage sectors in an embodiment of the present application;

[0030] Figure 5 is a switch switching timing diagram in an embodiment of the present application;

[0031] Figure 6 is an antenna hemispherical radiation surface gain diagram in an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Usually, the components of the embodiments of the present application described and illustrated herein can be arranged and designed in various different configurations. Embodiment

[0033] To ensure no blind spots in the communication coverage design, in addition to a horizontal coverage angle of 0 - 360°, the pitch coverage angle design of UAV communication also needs to satisfy 0 - 180° coverage.

[0034] Referring to Figure 1 , a hemispherical antenna beam selection method for 5G communication includes the following steps:

[0035] Step S1: Construct a 5G integrated base station module with m ports for the base station channels;

[0036] Step S2: Construct an antenna module;

[0037] Step S3: Power the 5G integrated base station module constructed in Step S1 and the antenna module in Step S2;

[0038] Step S4: The 5G integrated base station module identifies and reads the ID number of the antenna module, and determines the antenna type based on the ID number. When it is identified as a hemisphere antenna, an algorithm program for driving the hemisphere antenna is triggered. When it is identified as a common antenna, a standard mode for cooperating with the common directional antenna is adopted;

[0039] Step S5: The time synchronization module in the 5G integrated base station module gives the synchronization reference signal of the base station to the control processor in the hemisphere antenna module to provide a time reference for the subsequent switch switching; the hemisphere antenna module ensures synchronization with the base station through time reference synchronization;

[0040] Step S6: The control processor in Step S5 drives the switch of each port to perform an n-path cyclic traversal, connecting m * n sub-antennas, and realizing m * n sector coverage through the beam pointing coverage of the antenna.

[0041] Refer to Figure 2 and Figure 3 , in specific implementation, the optimal choice for the base station channels in Step S1 is 4 ports; at this time, the control processor drives the switch of each port to perform an 8-path cyclic traversal to connect 32 sub-antennas, and realizes 32 sector coverage through the beam pointing coverage of the antenna.

[0042] The 5G integrated base station module constructed in Step S1 integrates RRU, BBU, 5GC and IMS core network, aiming at long-distance coverage for mobile networking, suitable for airborne mobile deployment application scenarios, can meet application requirements such as public network coverage and industry private network, and provides functions such as wireless access, wireless resource management, mobility management and service switching; the base station reads back the ID number of the antenna and provides a 1pps time reference signal to the hemisphere antenna at the same time.

[0043] The hemisphere antenna module constructed in Step S2 includes an antenna interface module, a radio frequency switch module, a clock synchronization circuit module, a sub-antenna module, a control processor module and a power management circuit module; the antenna interface module includes a radio frequency interface and a digital interface on the top plane of the hemisphere. The radio frequency interface is m SMA interfaces and is connected to the 5G integrated station through a feeder; the digital interface is a serial port and is connected to the base station to receive the 1pps time reference signal from the base station and transmit back the antenna ID signal; in specific implementation, 4 SMA interfaces can be set, as Figure 2 shown.

[0044] The RF switch module includes m SPnT RF switches. Each switch can expand 1-way RF transceiver into n-way RF transceiver through switch control. In a specific implementation, the RF switch module includes 4 SP8T RF switches, as Figure 2 shown.

[0045] The clock synchronization circuit module includes a TCXO and a phase-locked loop circuit, which is responsible for receiving the 1pps time reference signal transmitted from the 5G integrated station, and completing a new clock output through the internal phase discrimination and frequency locking circuit to ensure that the clock is synchronized with the 5G signal clock.

[0046] The sub-antenna module is pasted on the spherical dielectric carrier board. Each sub-antenna has a narrow beam and high gain. Through spatial distribution techniques, it realizes a coverage of 0~360° horizontally and 0~180° vertically, and finally realizes that the radiation surface presents a complete hemisphere.

[0047] The control processor module is used to control the selection and switching of m switches, and control the dwell time and switching protection time of each 1-n path of the switch. In a specific implementation, referring to Figure 2 , a control processor module controls the selection and switching of 4 switches, and controls the dwell time and switching protection time of each 1-8 path of the switch.

[0048] The power management circuit module includes an airborne battery, which supplies power to the switches, TCXO and phase-locked loop chips. It should be noted that the power management circuit module defaults to a constant output of 5V; one of the 5V outputs is changed to 3.3V through an LDO to supply power to the control processor.

[0049] Referring to Figure 3 , the horizontal 3dB beamwidth of the sub-antenna module is between ±18°, and the vertical 3dB beamwidth is between ±12°.

[0050] Multiple sub-antennas are spliced to form a hemisphere with a horizontal surround of 360° and a vertical of 180°.

[0051] In a specific implementation, there are 32 sub-antennas in 4 layers from top to bottom, and the spacing between array elements in each layer is 0.75λ, where λ is the wavelength corresponding to the center frequency.

[0052] Referring to Figure 3-4 , the number of sub-antennas in the 1st to 4th layers is 10, 10, 8, and 4 respectively; the array element numbers in the 1st layer are 1-10, the array element numbers in the 2nd layer are 11-20, the array element numbers in the 3rd layer are 21-28, and the array element numbers in the 4th layer are 29-32.

[0053] The normal directions of the array elements in the vertical direction are -12°, -34°, -56°, and -78° respectively; the normal gain of the antenna is 14dBi, and the vertical 3dB beamwidth is ±12°, which can cover 0~90°; 0° is the horizontal plane direction, and -90° is the free-fall direction.

[0054]

[0055] Table 1

[0056] Referring to Table 1, for the first layer and the second layer, the normal horizontal angles of the array elements are 18°, 54°, 90°, 126°, 162°, 198°, 234°, 270°, 306°, and 342° respectively. Since the normal gain of the antenna is 14 dBi and the horizontal 3-dB lobe is ±18°, the horizontal coverage angles of the array elements are 0~36°, 36~72°, 72~108°, 108~144°, 144~180°, 180~216°, 216~252°, 252~288°, 288~324°, and 324~360°.

[0057] For the third layer, the normal horizontal angles of the array elements are 22.5°, 67.5°, 112.5°, 157.5°, 202.5°, 247.5°, 292.5°, and 337.5° respectively. Since the normal gain of the array elements in the third layer is 14 dBi and the horizontal 3-dB lobe is ±22.5°.

[0058] The horizontal coverage angles of the array elements are 0~45°, 45~90°, 90~135°, 135~180°, 180~225°, 225~270°, 270~315°, and 315~360°.

[0059] For the fourth layer, the normal horizontal angles of the array elements are 45°, 135°, 225°, and 315° respectively. Since the normal gain of the array elements in the fourth layer is 11 dBi and the horizontal 3-dB lobe is ±45°, the horizontal coverage angles of the array elements are 0~45°, 45~90°, 90~135°, 135~180°, 180~225°, 225~270°, 270~315°, and 315~360°. The radiation directions of the 32 sub-antennas of the hemispherical antenna are mapped to the ground, dividing the circle with a radius of 10 km into 32 sectors. The sector numbers are the sub-antenna numbers. The inner ring is sectors 29 - 32, the second ring is sectors 21 - 28, the third ring is sectors 11 - 20, and the outer ring is sectors 1 - 10; and the structures of the 32 sub-antennas are the same, and the radius of the radiation cavity is 0.5λ.

[0060] Refer to Figure 5, after the antenna is synchronized with the base station, the control processor drives 4 switches to perform path switching. The initial state is to select sub-antennas 1, 9, 17, and 25, and they are sequentially switched to 2, 10, 18, 26; 3, 11, 19, 27; 4, 12, 20, 28; 5, 13, 21, 29; 6, 14, 22, 30; 7, 15, 23, 31; 8, 16, 24, 32, and then return to the initial state for cyclic traversal. It should be noted that the dwell time of each beam needs to be greater than or equal to the transmission period of the SSB;

[0061] In specific implementation, the base station sets the SSB transmission period to 10 mS, and designs the dwell time of each beam to be 10 mS to complete the uplink and downlink services.

[0062] In specific implementation, the switching time of the switch is 1 μS, which occupies the cyclic prefix of the first OFDM symbol within the next 10 mS; the switch cyclically traverses and switches 1 - 8 rounds, and the traversal period: 10 mS * 8 = 80 mS.

[0063] Refer to Figure 6 , through the antenna array plus high-speed electronic switch for traversal scanning, and finally through electromagnetic simulation, the omnidirectional gain of the hemisphere coverage is greater than 9 dBi; it can be obtained that the gain in the dark area is greater than 9 dBi, and the gain has completely covered the hemisphere.

[0064] The insertion loss of the RF switch is usually less than 0.5 dB, so the equivalent gain: 9 dBi - 0.5 dB = 8.5 dBi.

[0065] In summary, the beam selection method in this application can achieve an antenna gain greater than 8 dBi in any direction of the hemisphere radiation surface, and when the UAV base station flies at an altitude of 500 - 5000 meters, the communication coverage radius for ground mobile phones is greater than 10 kilometers, and for any flight attitude, when the mobile phone is within a circle with a radius of 10 kilometers, there is no communication coverage blind area.

[0066] At the same time, the circuit complexity and cost in this application are effectively compressed, and the applicable range is wider.

[0067] The above-described embodiments only represent the preferred implementation modes of this application. The description is relatively specific and detailed, but it should not be construed as a limitation on the patent scope of this application. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several deformations, improvements, and substitutions can still be made, and these all belong to the protection scope of this application.

Claims

1. A hemispherical antenna beam selection method for 5G communication, characterized in that It includes the following steps: Step S1: Construct a 5G integrated base station module with m ports for the base station channels; Step S2: Construct an antenna module; Step S3: Power the 5G integrated base station module constructed in Step S1 and the antenna module in Step S2; Step S4: The 5G integrated base station module identifies and reads the ID number of the antenna module, determines the antenna type based on the ID number. When it is determined to be a hemispherical antenna, it triggers the algorithm program to drive the hemispherical antenna. When it is determined to be a common antenna, it adopts the standard mode for cooperation with the common directional antenna; Step S5: The time synchronization module in the 5G integrated base station module gives the synchronization reference signal of the base station to the control processor in the hemispherical antenna module, providing a time reference for the subsequent switch switching; The hemispherical antenna module ensures synchronization with the base station through time reference synchronization; Step S6: The control processor in Step S5 drives the switch of each port to perform an n-way cyclic traversal, realizing the connection of m*n sub-antennas; The sub-antennas are from top to bottom in L layers, and the horizontal 3dB beamwidth of the sub-antenna module in the p-th layer is ， The vertical 3dB beamwidth of all layer antenna modules is: ， wherein, , 1 ≤ p ≤ L, is the communication frequency, with the unit of MHz, and r is the radius of the hemispherical antenna, with the unit of meter; There are L layers of m*n sub-antenna modules from top to bottom, and the spacing between the array elements in each layer is 0.75λ, where λ is the wavelength corresponding to the center frequency.

2. A method for hemispherical antenna beam selection for 5G communication according to claim 1, characterized in that, The 5G integrated base station module constructed in Step S1 integrates RRU, BBU, 5GC and IMS core network.

3. A hemispherical antenna beam selection method for 5G communication according to claim 1, characterized in that, The hemispherical antenna module constructed in Step S2 includes an antenna interface module, a radio frequency switch module, a clock synchronization circuit module, a sub-antenna module, a control processor module and a power management circuit module; The antenna interface module includes a radio frequency interface and a digital interface on the hemispherical top plane. The radio frequency interface has m SMA interfaces and is connected to the 5G integrated station through a feeder; the digital interface is a serial port connected to the base station, receiving the 1pps time reference signal from the base station and transmitting back the antenna ID signal; The radio frequency switch module includes m SPnT radio frequency switches, and each switch realizes the expansion of 1-way radio frequency transceiver into n-way radio frequency transceiver through switch control; The clock synchronization circuit module includes a TCXO and a phase-locked loop circuit, which is responsible for receiving the 1pps time reference signal from the 5G integrated station, and completing the output of a new clock through the internal phase discrimination and frequency locking circuit to ensure the clock synchronization with the 5G signal clock; The sub-antenna module is pasted on the dielectric carrier board of the spherical surface; The control processor module is used to control the selection and switching of m SPnT radio frequency switches, and control the dwell time and switching protection time of the 1-n channels of each SPnT radio frequency switch; The power management circuit module contains an on-board battery to power the switch, TCXO and phase-locked loop chip.

4. A hemispherical antenna beam selection method for 5G communication according to claim 1, characterized in that, After the antenna and the base station are synchronized, the control processor drives the switch to perform path switching. In the initial state, the first group of sub-antennas is selected, and then it returns to the initial state after sequentially switching according to the sequence number of each group of sub-antennas, performing a cyclic traversal; The beam dwell time is greater than or equal to the transmission period of the SSB; During the switching process, the number of the sub-antenna module selected by the i-th switch is j+(i - 1)*n, where 1≤i≤m and 1≤j≤n.

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