WO2018232748A1

WO2018232748A1 - Integrated antenna element, antenna unit, and multi-array antenna thereof

Info

Publication number: WO2018232748A1
Application number: PCT/CN2017/089814
Authority: WO
Inventors: Samb DOUDOU; Zhonglin Wu; Jiatong LIU; Qingchen Chu
Original assignee: Tongyu Communication Inc.
Priority date: 2017-06-23
Filing date: 2017-06-23
Publication date: 2018-12-27

Abstract

An antenna element, antenna unit and multi-array antenna are proposed. The antenna unit includes a filtering device and an integrated antenna element. The integrated antenna element comprises a primary PCB and a conducting material used as a radiating element. The filtering device has the primary PCB as a filter lid, and comprises one or more filters; each filter has one output formed on top of the primary PCB and capable of exciting the radiating element through slot-coupled fed.

Description

Title of Invention: INTEGRATED ANTENNA ELEMENT,

ANTENNA UNIT, AND MULTI-ARRAY ANTENNA THEREOF Technical Field

[0001] This application generally relates to the field of communication system, and particularly, to an integrated antenna element, an antenna unit and a Massive MIMO antenna thereof.

Background Art

[0002] Remarkable progress in wireless aiming to advance the state of the art of the communication field putting it in the context of 4.5/5G architectures and beyond. These fastest emerging systems generate numerous challenges on the antenna system design as new frequency bands should be fully covered to meet the demands of various application levels impacting so the radio network design involving for example the propagation and cell planning mechanisms. Besides these new bands, few RF-part from traditional radio unit are being put close to the antenna. Massive MIMO antenna platform being promoted recently where large sub-arrays are collocated both in azimuth and elevation plan with embedded calibration networks to enable 3D beamforming. Generally, Massive MIMO antenna design imposes multiple RF-ports in order of 32, 64, 128... that need to be connected each to a band-pass filter keeping narrow band width of signal of interest going through a Transmitting/Receiving circuit (from/to a radio unit). These filters impose additional cost from extra connectors, complex structure integration and over weighted as different hardware have to be designed separately prior to being integrated.

Technical Problem

[0003] A main object of the present invention is to provide an antenna unit, which can

simplify the structure and reduce the cost.

[0004] A secondary object of the present invention is to provide a multi-array antenna,

which has a simple structure and low cost.

[0005] A further object of the present invention is to provide an integrated antenna element, which has a compact and simple structure.

[0006] Another object of the present invention is to provide a transmission method.

[0007] The final object of the present invention is to provide a receiving method.

Solution to Problem

Technical Solution

[0008] To obtain the above object, an antenna unit provided in the present invention

comprising a filtering device and an integrated antenna element. The integrated antenna element comprises a primary PCB and a conducting material used as a radiating element; the filtering device has the primary PCB as a filter lid, and comprises one or more filters; each filter has one output formed on top of the primary PCB and capable of exciting the radiating element through slot-coupled fed.

[0009] In some embodiment, the output of each filter is a microstrip line formed on top of the primary PCB; each output of each filter is coupled to one slot formed on top of the primary PCB to excite an RF polarized-wave.

[0010] In some embodiment, a conducting material layer is formed on top of the primary PCB as a primary ground; a secondary PCB is set on top of the primary ground; and another conducting material layer is formed on top of the secondary PCB as a secondary ground.

[0011] In some embodiment, a primary microstrip line is etched on the primary ground to form a primary output of a primary filter; a primary slot is etched on the secondary ground coupled to the primary microstrip line on the primary ground, whereby a first RF polarized-wave can be excited from the primary slot.

[0012] In some embodiment, a secondary microstrip line is etched on the primary ground on top of the primary PCB to form a secondary outlet of a secondary filter; a secondary slot is etched on the secondary ground coupled to the secondary microstrip line on the primary ground, whereby a second RF polarized-wave is excited from the secondary slot.

[0013] Preferably, the primary microstrip line crosses the primary slot; and the secondary microstrip line crosses the secondary microstrip line; whereby to form a dual- polarization.

[0014] Preferably, a size of the conducting material as the radiating element and its distance from the primary PCB is tuned to match a desired band of interest.

[0015] Preferably, a fixture element is placed between the conducting material and the

primary PCB for linking the primary conducting material; the fixture element is a mechanical fixture and is used to keep the primary conducting material at the desired height.

[0016] In some embodiment, the fixture element is a dielectric material.

[0017] In some embodiment, more conducting materials are added on top of the primary conducting material for bandwidth improvement; the conducting material is in a shape of a panel parallel to the primary PCB.

[0018] In some embodiment, the filtering device comprises two band-pass filters; the two filters are housed in same cavity so that a common lid can be used, or they are housed in different cavities where still a common lid is used.

[0019] Further, two walls running parallel are extending close to filter edges of the filtering device to support a cavity of the one or more filters and at same time serving as re- fleeting walls enabling to control 3dB azimuth beam generated by the radiating element based on a height of the walls.

[0020] To obtain the above object, a multi-array antenna further provided in the present invention comprising multiple antenna units above, and the multiple antenna units are co-located to form sub-arrays.

[0021] To obtain the above object, an integrated antenna element provided in the present invention comprising a primary PCB and a conducting material as a radiating element placed above the primary PCB within a height; the primary PCB is used as a filter lid, a microstrip line as an output of one filter is formed on top of the PCB, and is capable of exciting the radiating element through slot-coupled fed.

[0022] In some embodiment, the output of each filter is coupled to one slot formed on top of the primary PCB for exciting the radiating element to form an RF polarized-wave.

[0023] A transmission method is provided in accordance with the embodiment, comprising:

[0024] receiving signal from a base station antenna transmitting path;

[0025] filtering and keeping only the narrow-band of interest signal by a filtering device;

[0026] coupling the signal to a primary and secondary slots on top of a primary PCB from outputs of the primary and the secondary filters;

[0027] sending the signal to the radiating element through slot-coupled fed; and

[0028] exciting the radiating element and radiating its received signal throughout the space.

[0029] A receiving method is provided in accordance with the embodiment, comprising:

[0030] receiving signal by a conducting material as a radiating element;

[0031] sending the received signal to a primary and secondary slots on top of the primary

PCB through slot-coupled fed;

[0032] coupling the signal to a corresponding primary or secondary microstrip lines;

[0033] sending each the received signal to a primary and secondary filters which keep the narrow-band of signal of interest; and

[0034] transferring the filtered signals to a base station antenna receiving path.

Advantageous Effects of Invention

Advantageous Effects

[0035] In accordance with the embodiments, the present invention has advantages that:

[0036] a low cost, simple integrated antenna element is obtained since the microstrip line printed on top of the PCB that can be used to excite a conducting material (used as radiating element) through slot-coupled fed, so that no connector, and no die-casted and heavy support are needed between the radiating element and the feeding network.

[0037] Further, a low cost, simple integrated antenna is obtained where two compact filters having each PCB as lid with output of microstrip line printed on top of the PCB that can be used to excite a conducting material (used as radiating element) through slot- coupled fed. So that no connectors needed between filter and antenna element; no die- casted and heavy support needed between the radiating element and the filter lid. '

[0038] Massive MIMO antenna is obtained with simple structure accordingly.

[0039] The above-mentioned features, as well as other features, aspects, and advantages of the present technology will now be described in connection with various embodiments of the invention, in reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to limit the invention. Brief Description of Drawings

Description of Drawings

[0040] FIG. 1 illustrates a cross-sectional view of an antenna element in accordance with an embodiment of the present invention;

[0041] FIG. 2(a) illustrates a plan view of a primary ground in accordance with one embodiment of the present invention;

[0042] FIG. 2(b) illustrates a plan view of a secondary ground in accordance with another embodiment of the present invention;

[0043] FIG. 3 illustrates various slot structures for example (a), (b), (c) and (d) in accordance with one embodiment of the present invention;

[0044] FIG. 4 illustrates a cross-sectional view of the antenna element in accordance with another embodiment of the present invention;

[0045] FIG. 5 represents the return loss for a system operating at center frequency of

2.6GHz in accordance with one embodiment of the present invention; and

[0046] FIG. 6 illustrates a cross-sectional view of a multi-array antenna element in accordance with another embodiment of the present invention.

Best Mode for Carrying out the Invention

Best Mode

[0047] The provided figures and the following description of certain embodiments of the invention are not intended to limit the invention to these embodiments, but rather, are provided to enable any person skilled in the art to make and use this invention.

[0048] In accordance with an embodiment of this invention, a low cost integrated antenna

200 is proposed where two compact filters 1 have each PCB 2, 4 and the PCB 2 is used as lid with output of microstrip line printed on top of the PCB that can be used to excite a conducting material which is used as a radiating element 6 through slot- coupled fed. So that no connectors needed between filter 1 and antenna element 20. No die-casted or heavy support is needed between the radiating element 6 and the filter lid 2. Also, filter lid 2 can be used as radiating element grounding support. The following will be described in detail.

[0049] In these embodiments, the same element or the similar element is recited by the same reference number. Hereinafter in the following description, the primary PCB and the filter lid are referred as the same number "2"; and the conductive material, primary conductive material, and the radiating element are referred as the same number "6" for convenience.

[0050] Referring to FIGS 1-2, the antenna 200 in accordance with this embodiment,

comprises a filtering device 1 and an integrated antenna element 20. The integrated antenna element 20 comprises a primary PCB 2 and a primary conducting material 6 used as the radiating element. The filtering device 1 has the primary PCB 2 as a filter lid, and comprises one or more filters; each filter has one output formed on top of the primary PCB 2 and capable of exciting the radiating element 6 through slot-coupled fed to form an RF polarized-wave.

[0051] The output of each filter is a microstrip line formed on top of the primary PCB 2; each output of each filter is coupled to one slot formed on top of the primary PCB 2 to excite an RF polarized-wave.

[0052] The first conducting material 6 for example in a shape of panel parallel to the

primary PCB 2, is placed above the primary PCB 2 within a height.

[0053] Further, the antenna 200 as an integrated filter dual-polarized antenna is provided in accordance with this embodiment. Where the filtering device 1 comprises a primary filter and a secondary filter (not labeled). The primary filter has one input 100 and one output. The secondary filter has one input 101 and one output.

[0054] The two filters can be housed in same cavity so that a common lid 2 can be used; or they can be housed in different cavities where still a common lid 2 is used. Preferably, the filters are band-pass filters.

[0055] A conducting material layer is formed on top surface of the primary PCB 2 and

serves as a primary ground 3. The output of the primary filter is a primary microstrip line 8 etched on the primary ground 3.

[0056] A secondary PCB 4 is further provided on top of the primary ground 3.

[0057] Another conducting material layer is formed on top surface of the secondary PCB 4 and serves as a secondary ground 5.

[0058] The output of the secondary filter is a secondary microstrip line 7 etched on the

primary ground 3.

[0059] A primary slot 10 is etched on the secondary ground 5 coupled to the primary microstrip line 8 on the primary ground 3, and preferably crossing the primary microstrip line 8; so that a first RF polarized-wave 21 can be excited from the primary slot 10. The microstrip line 8 is printed on top of the PCB 2 that can be used to excite the conducting material 6 through slot-coupled fed.

[0060] A secondary slot 9 is etched on the secondary ground 5 coupled to the secondary microstrip line 7 on the primary ground 3, and preferably crossing the secondary mi- crostrip line 7; so that a second RF polarized- wave 22 can be excited from the secondary slot 9. The microstrip line 7 printed on top of the PCB 2 that can be used to excite the conducting material 6 through slot-coupled fed too.

[0061] The slot structure of slots 9, 10 is not limited and can be of rectangular, I-shaped 11 and 14, H-shaped 12, L-shaped 13, etc., referring to FIG. 3.

[0062] In various embodiment, the slot 9 or 10 can be configured according to the microstrip line 7 or 8 to excite the corresponding conducting material 6 whereby to obtain various polarization not only of a dual polarization, or to obtain various dual-polarization, such as Horizontal and Vertical, Dual slant +/-45deg, etc.

[0063] The primary PCB 2 as the filter lid horizontally covered on top of the filtering device 1, the primary ground 3 which is a conducting material layer attached on top of the PCB 2, the secondary PCB 4 further horizontally covered on top of the ground 3, and the secondary ground 5 which is a conducting material layer attached on top of the PCB 4 together forms an integrated and compact antenna element 20 in a form of multilayer; where the microstrip line 7, 8 etched on primary ground 3 is coupled to the slot 9, 10 etched on the secondary ground 5 to form RF polarized waves.

[0064] At least a primary conducting material 6 for example in a shape of panel is placed above the secondary ground 5 within a height; so that the integrated filter dual- polarized antenna 200 can be obtained with the filters lid 2 serving also as grounding support of the coupled fed antenna. This provides a low cost integrated design that can be used in a Massive MIMO or active antenna arrays as no connectors needed between filters and antenna element; and the antenna element 20 uses the filter output as feed line exciting a conducting material panel (cheap component) through slot 9, 10.

[0065] The size of the primary conducting material 6 and its distance from the primary and secondary slots 9, 10 can be tuned to match desired band of interest. In other words, a size of the conducting material as the radiating element 6 and its distance from the primary PCB 2 is tuned to match a desired band of interest.

[0066] Referring to FIG. 4 in accordance with another embodiment, a secondary or more conducting materials 15, 16 can be added on top of the primary conducting material 6 for bandwidth improvement; and the shape of such conducting material can be square, rectangular, circular, or any other adapted shape.

[0067] In some embodiment, two walls (not labeled) running parallel are extending close to the band-pass filter edges of the filtering device 1 to support the cavity of the filters and at same time serving as reflecting walls enabling to control the 3dB azimuth beam generated by the radiating element 20 and based on the height of the walls.

[0068] Further referring to FIG. 5, the figure represents the return loss for an antenna system operating at center frequency of 2.6GHz. It can be realized that 160MHz bandwidth is obtained for return loss requirements of -15dB. [0069] A fixture element is placed between the primary conducting material 6 and the secondary ground for linking the primary conducting material 6 to the lid 2. And the primary and secondary slots 9, 10 do not need to have same structure. Any fixture element 30 are applicable for linking the primary conducting material on the lid 2, and conductive performance is not necessary to be considered. The fixture element 30 can refer to a mechanical fixture. In other word, it can be a dielectric material, and is used just to keep the primary conducting material at the desired height.

[0070] The antenna unit 200 is proposed in accordance with above embodiments, where the compact filtering device 1 having the primary PCB 2 as lid with output being mi- crostrip line printed on top of the PCB that can be used to excite a conducting material 6 as the radiating element through slot-coupled fed, in such way that no connectors needed between filters and antenna element 20. Therefore, the antenna unit 200 has very simple structure and lower cost.

[0071] Furthermore, no die-casted and heavy support is needed between the radiating

element 6 and the filter lid 2. Also, the filter lid 2 can be used as radiating element grounding support. Thereby, the antenna unit 200 is further can simplified cost down, and is adapted for a Massive MIMO antenna.

[0072] A Massive MIMO antenna as large sub-arrays is available by collocating multiple antenna units 200 above, and each antenna unit 200 is co-located to form sub-arrays.

[0073] Each input 100, 101 of the band-pass filter at its bottom end can be connected each to a Transmitting/Receiving circuit (from/to a radio unit)where each of the band-pass filter can keep narrow band width of signal of interest going through.

[0074] In a transmission mode of the antenna unit, the primary and secondary band-pass filters keeps each only the narrow-band of interest from a base station antenna transmitting path. The outputs of the primary and the secondary filters are coupled to the primary and secondary slots respectively to excite the radiating element which radiates its received signal throughout the space. Therefore, a transmission method of the present invention comprises:

[0075] receiving signal from a base station antenna transmitting path;

[0076] filtering and keeping only the narrow-band of interest signal by the filtering device, and specifically by the primary and secondary band-pass filters;

[0077] coupling the signal to the primary and secondary slots on top of the primary PCB 2 from the outputs of the primary and the secondary filters;

[0078] sending the signal to the radiating element through slot-coupled fed; and

[0079] exciting the radiating element and radiating its received signal throughout the space.

[0080] In a receiving mode, the radiating element sends its received signal to the primary and secondary slots; based on which each slot couples its received signal to the corresponding primary or secondary microstrip lines namely the outputs of the filters. The primary and secondary microstrip line sends each its received signal to the primary and secondary filters which keep the narrow-band of signal of interest to a base station antenna receiving path. Therefore, a receiving method of the present invention comprises:

[0081] receiving signal by the radiating element;

[0082] sending the received signal to the primary and secondary slots on top of the primary PCB through slot-coupled fed;

[0083] coupling the signal to the corresponding primary or secondary microstrip lines;

[0084] sending each the received signal to the primary and secondary filters which keep the narrow-band of signal of interest; and

[0085] transferring the filtered signals to a base station antenna receiving path.

[0086] As used in the description and claims, the singular form "a", "an" and "the" include both singular and plural references unless the context clearly dictates otherwise. At times, the claims and disclosure may include terms such as "a plurality," "one or more," or "at least one;" however, the absence of such terms is not intended to mean, and should not be interpreted to mean, that a plurality is not conceived.

[0087] As used herein, the term "comprising", "comprises" or "composed of is intended to mean that the devices, systems, and methods include the recited elements, and may additionally include any other elements. "Consisting essentially of shall mean that the devices, systems, and methods include the recited elements and exclude other elements of essential significance to the combination for the stated purpose. Thus, a system or method consisting essentially of the elements as defined herein would not exclude other materials, features, or steps that do not materially affect the basic and novel char- acteristic(s) of the claimed invention. "Consisting of shall mean that the devices, systems, and methods include the recited elements and exclude anything more than a trivial or inconsequential element or step. Embodiments defined by each of these transitional terms are within the scope of this disclosure.

[0088] The examples and illustrations included herein show, by way of illustration and not of limitation, specific embodiments in which the subject matter may be practiced.

Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept, if more than one is disclosed. Thus, although specific embodiments have been illustrated and described herein, any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various em- bodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.

Claims

An antenna unit comprising a filtering device and an integrated antenna element; characterized in that the integrated antenna element comprises a primary PCB and a conducting material used as a radiating element; the filtering device has the primary PCB as a filter lid, and comprises one or more filters; each filter has one output formed on top of the primary PCB and capable of exciting the radiating element through slot-coupled fed.

According to the antenna unit in claim 1, characterized in that the output of each filter is a microstrip line formed on top of the primary PCB; each output of each filter is coupled to one slot formed on top of the primary PCB to excite an RF polarized-wave.

According to the antenna unit in claim 2, characterized in that a conducting material layer is formed on top of the primary PCB as a primary ground; a secondary PCB is set on top of the primary ground; and another conducting material layer is formed on top of the secondary PCB as a secondary ground.

According to the antenna unit in claim 3, characterized in that a primary microstrip line is etched on the primary ground to form a primary output of a primary filter; a primary slot is etched on the secondary ground coupled to the primary microstrip line on the primary ground, whereby a first RF polarized-wave can be excited from the primary slot.

According to the antenna unit in claim 3, characterized in that a secondary microstrip line is etched on the primary ground on top of the primary PCB to form a secondary outlet of a secondary filter; a secondary slot is etched on the secondary ground coupled to the secondary microstrip line on the primary ground, whereby a second RF polarized-wave is excited from the secondary slot.

According to the antenna unit in any of claims 4 to 5, characterized in that the primary microstrip line crosses the primary slot; and the secondary microstrip line crosses the secondary microstrip line;

whereby to form a dual-polarization.

According to the antenna unit in claim 1, characterized in that a size of the conducting material as the radiating element and its distance from the primary PCB is tuned to match a desired band of interest.

According to the antenna unit in claim 1, characterized in that a fixture element is placed between the conducting material and the primary PCB for linking the primary conducting material; the fixture element is a mechanical fixture and is used to keep the primary conducting material at the desired height.

According to the antenna unit in claim 8, characterized in that the fixture element is a dielectric material.

According to the antenna unit in claim 1, characterized in that more conducting materials are added on top of the primary conducting material for bandwidth improvement; the conducting material is in a shape of a panel parallel to the primary PCB.

According to the antenna unit in claim 1, characterized in that the filtering device comprises two band-pass filters; the two filters are housed in same cavity so that a common lid can be used, or they are housed in different cavities where still a common lid is used.

According to the antenna unit in claim 1, characterized in that two walls running parallel are extending close to filter edges of the filtering device to support a cavity of the one or more filters and at same time serving as reflecting walls enabling to control 3dB azimuth beam generated by the radiating element based on a height of the walls. A multi-array antenna comprising multiple antenna units in any of claims 1-12, characterized in that the multiple antenna units are co- located to form sub-arrays.

An integrated antenna element comprising:

a primary PCB; and

a conducting material as a radiating element placed above the primary PCB within a height;

characterized in that:

the primary PCB is used as a filter lid, a microstrip line as an output of one filter is formed on top of the primary PCB, and is capable of exciting the radiating element through slot-coupled fed.

According to the integrated antenna element in claim 14, characterized in that the output of each filter is coupled to one slot formed on top of the primary PCB for exciting the radiating element to form an RF polarized-wave.

According to the integrated antenna element in claim 15, characterized in that a conducting material layer is formed on top of the primary PCB as a primary ground; a secondary PCB is set on top of the primary ground; and another conducting material layer is formed on top of the secondary PCB as a secondary ground.

[Claim 17] According to the integrated antenna element in claim 16, characterized in that a primary microstrip line is etched on the primary ground to form a primary output of a primary filter; a primary slot is etched on the secondary ground coupled to the primary microstrip line on the primary ground, whereby a first RF polarized-wave can be excited from the primary slot.

[Claim 18] According to the integrated antenna element in claim 16, characterized in that a secondary microstrip line is etched on the primary ground on top of the primary PCB to form a secondary outlet of a secondary filter; a secondary slot is etched on the secondary ground coupled to the secondary microstrip line on the primary ground, whereby a second RF polarized-wave is excited from the secondary slot.

[Claim 19] According to the integrated antenna element in any of claims 17-18, characterized in that the primary microstrip line crosses the primary slot; and the secondary microstrip line crosses the secondary microstrip line; whereby to form a dual-polarization.

[Claim 20] According to the integrated antenna element in claim 14, characterized in that a size of the conducting material as the radiating element and its distance from the primary PCB is tuned to match a desired band of interest; more conducting materials are added on top of the primary conducting material for bandwidth improvement; the conducting material is in a shape of a panel parallel to the primary PCB.

[Claim 21] According to the integrated antenna element in claim 14, characterized in that a fixture element is placed between the conducting material and the primary PCB for linking the primary conducting material; the fixture element is a mechanical fixture and is used to keep the primary conducting material at the desired height.

[Claim 22] A transmission method comprising:

receiving signal from a base station antenna transmitting path;

filtering and keeping only the narrow-band of interest signal by a filtering device;

coupling the signal to a primary and secondary slots on top of a primary PCB from outputs of the primary and the secondary filters;

sending the signal to the radiating element through slot-coupled fed; and

exciting the radiating element and radiating its received signal throughout the space. [Claim 23] A receiving method comprising:

receiving signal by a conducting material as a radiating element;

sending the received signal to a primary and secondary slots on top of the primary PCB through slot-coupled fed;

coupling the signal to a corresponding primary or secondary microstrip lines;

sending the received signal to a primary and secondary filters which keep the narrow-band of signal of interest; and

transferring the filtered signals to a base station antenna receiving path.