The present disclosure relates to a wireless communication device and in particular, a low visual impact highly efficient millimeter lens antenna repeater that can be mounted on a street corner, carried around by a consumer to direct and refocus signals for a personal wireless hotspot or mounted on a lamppost for high data rate communications in microwave-based networks, for example 5th-generation (“5G”) mm-wave networks. These repeaters are able to deliver high data rate communications to areas not served by the Line-of-Site (LoS) coverage of a mm-wave base station by receiving and then redirecting signals to and from the base station with high gain, low loss by means of a dielectric lens. The present disclosure enables additional functionality for an active or passive repeater employing a lens antenna.
It is well known that the coverage area of a mobile radio base station may be extended by means of arrangements known as repeaters. These are commonly employed to add coverage in areas in which transmission between a base station and a user equipment such as a mobile phone or computing device, is blocked by buildings, trees or other obstacles. A repeater according to prior art is typically provided with a first antenna referred to as a donor antenna that transmits signals to and from a base station, and a second antenna referred to as a service antenna that communicates with users in the extended area of coverage. Both the donor antenna and the service antenna transmit and receive radio signals. An arrangement in which the donor and service antennas are directly connected by radio frequency transmission lines is known as a passive repeater. Arrangements in which the donor and service antennas are connected through radio frequency circuit arrangements such as amplifiers are known as active repeaters. At frequencies greater than 6 GHz, now being developed for mobile radio use, the propagation characteristics of radio waves becomes similar to those of light, so propagation within city areas becomes problematic; a signal directed along a city street will not propagate into side streets, even one close to the base station, so the use of repeaters becomes an essential tool for the provision of adequate coverage,
The Applicant's previous application U.S. Ser. No. 16/822,778, the entire contents of which is hereby incorporated by reference. discloses (among other things) both active and passive repeater arrangements based on the use of at least one substantially spherical lens formed from at least one low loss dielectric material and provided with feed arrangements to support a bi-directional donor beam linking the repeater to a base is station and a service beam linking the repeater to users' equipment. This prior application further describes arrangements whereby a single lens may be provided with additional feed arrangements to support configurations comprising multiple service beams and/or multiple user beams.
The radio frequency transmission medium 4 may optionally comprise amplifying circuit arrangements 9 which increase the power level of received signals before retransmission. Such amplifying circuit arrangements preferably operate bidirectionally, amplifying signals applied at a first connection port and delivering them to a second output port, while simultaneously amplifying signals applied at the second port and delivering them to the first port. A repeater with directly connected donor and service feeds with no intermediate amplifying circuits is known as a passive repeater; a repeater comprising amplifying circuit arrangements is known as an active repeater.
The operation of a passive antenna such as a lens antenna is reciprocal, that is to say its characteristics such as its gain and beamwidth are identical whether it is used at a given frequency for the transmission or the reception of radio signals, so even where not specifically mentioned herein it can be assumed that the characteristics of each antenna are identical for transmission or reception.
The intensity of radio signals arriving at the repeater from a donor base station, and also from a user device located in a service beam, are characterized by their power density measured in watts per square meter. It therefore follows that the diameter of the spherical lens determines the amount of power intercepted. Increasing the diameter of the lens increases the intercepted power, permitting a longer distance between the donor base station and the repeater or a larger range for the service beam. However, increasing the diameter of the lens also reduces the beamwidth of the donor and service beams. As the donor beam becomes narrower, it becomes increasingly difficult to align the donor feed unit with sufficient accuracy to direct the maximum of the donor beam towards the donor base station. Narrowing of the service beam extends the range of the service area but reduces its angular extent; this may be a desirable effect in some circumstances, but the limited angular extent of the service area may be a disadvantage in other circumstances.
It has been found in practice that in some circumstances it is advantageous to adapt the shape of beams provided by a repeater, for example to widen the area over which service is provided by one or more service beams, or to facilitate the alignment of a donor beam on a supporting base station. Among other things, the present disclosure provides for this adjustment of beam shape, thereby extending the utility and range of applications of a repeater employing a lens antenna.
The present disclosure relates to a wireless repeater device provided with at least one lens antenna and associated feed units, together with arrangements to enable at least one feed unit to be displaced in a radial direction with respect to the lens, thereby varying the shape of the radiation pattern formed by the said lens and said feed unit. The arrangement disclosed may be applied to a plurality of feed units each supporting a donor beam or a service beam, and may be applied to active or passive repeaters.
This summary is not intended to identify all essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter. It is to be understood that both the foregoing general description and the following detailed description are exemplary and are intended to provide an overview or framework to understand the nature and character of the disclosure.
The accompanying drawings are incorporated in and constitute a part of his specification. It is to be understood that the drawings illustrate only some examples of the disclosure and other examples or combinations of various examples that are not specifically illustrated in the figures may still fall within the scope of this disclosure. Examples will now be described with additional detail through the use of the drawings, in which:
In describing the illustrative, non-limiting embodiments illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents that operate in similar manner to accomplish a similar purpose. Several embodiments are described for illustrative purposes, it being understood that the description and claims are not limited to the illustrated embodiments and other embodiments not specifically shown in the drawings may also be within the scope of this disclosure.
The present disclosure provides for an arrangement by which, in addition to adjustment of their mutual directions in both azimuth and elevation planes, beamwidths of donor and service beams may be independently varied.
When located at the focal point of the lens, the first feed unit 31 provides a highly directional beam 32. However, if displaced radially (toward or away, with respect to the initial position) from the center of the lens 30, for example to position 31a, the beam supported by the feed unit 31 becomes broader, for example as shown as beam 33. In a similar manner, the second feed unit 34 has a supporting beam 35. The second feed unit 34 may be displaced radially inwardly or outwardly to positions 34a, 34b, providing beams 36, 37 which are progressively wider than beam 35. It will be understood that the radial movement of the feed units may be provided by a sliding arrangement capable of providing any intermediate radial feed position and thereby providing corresponding continuous adjustment of beamwidth. As shown, a cable can connect the two feed units 31, 34. In addition, an amplifier can optionally be connected to the cable to boost the signal.
The arrangement described may be applied to a single feed unit or multiple feed units sharing a common spherical lens. In one example embodiment, some feed units may be arranged to lie at the focus of the lens. Others feed units may be provided with radially adjustable mounting arrangements according to the present disclosure, permitting adjustment of the gain and beamwidth of the service or user beams they support.
It will be understood that the term ‘dielectric lens’ includes any lens substantially constructed from dielectric material, whether having constant permittivity or having an effective permittivity that varies with radial distance from the center of the lens, for example a Luneberg lens. The term ‘dielectric material’ includes both natural dielectric materials, for example polyethylene or Rexolite®, and also artificial dielectric materials, for example those comprising conductive materials whether or not dispersed within a matrix of electrically non-conductive materials.
In the example embodiment shown, the positioning system includes one or more arcuate support members 108, 111, and first and second rotating connections that rotationally couple the support members 108, 111 to the spherical lens 100. The support members 108, 111 are at a fixed distance from the center of the spherical lens 100. The rotating connections can include, for example, first and second respective cylindrical axial members 101, 102 (for example, rods, pins or the like) and first and second respective flanged cylindrical sleeves 103, 104. In the example embodiment shown, the axial member 101, 102 and respective sleeves 103, 104 are positioned at opposite ends of the lens 100, here at the top and bottom, respectively, though other suitable positions can be utilized. The sleeve 104 may be extended radially to provide a mounting base 105 for the assembly. A first substantially planar disc 106 may be attached to the first sleeve 103 such that it remains rotationally fixed relative to the lens 100 and the base 105. In a similar manner, a second substantially planar disc 107 may be rotationally fixed relative to the second sleeve 104.
A first arcuate feed support member 108 is provided with first cylindrical bearing surface 109 at a first end and second cylindrical bearing surface 110 at a second end. Bearing surfaces 109, 110 are supported by sleeves 103, 104 respectively. For example, the lens 100 can have a bore and the bearing surfaces 109, 110 can have a central through-hole that receive the respective sleeves 103, 104; and the sleeves 103, 104 can have a central passage. The axial members 101, 102 can respectively pass through the central passage of the sleeves 103, 104 and the central through-hole of the bearing surfaces 109, 110 and engage the bore of the lens 100. A second arcuate feed support member 111 is provided with cylindrical bearing surfaces 112, 113 supported by sleeve members 103, 104. It will be understood that provided the axial lengths of bearing surfaces is small and their dimensions are suitably arranged, a plurality of arcuate feed support members may be supported by sleeves 103, 104, each support member being capable of substantially independent radial rotation around the axis defined by the said sleeves. Discs 106, 107 may be marked with scales to facilitate adjustment of the relative azimuth bearings of donor and service beams supported by the repeater.
A feed unit 120 is slidably attached to the arcuate support member 108 by first and second adjustable clamps 121, 122 which provide for movement in the radial and circumferential directions respectively relative to the center of spherical lens 100 and include means for fixing the position of feed unit 121 after adjustment is complete.
In one embodiment, the first clamp 121 is fixedly attached to the second clamp 122 (or both clamps 121, 122 can be fixedly attached to a common support or body member). The feed unit 120 is slidably received in the central opening of clamps 121 and 122. The clamps 121, 122 each have an opened or unlocked position, and a closed or locked position. In one example embodiment, the first clamp 121 can be placed in the unlocked position so that the feed unit 120 can slide radially, i.e., inward and/or outward with respect to the central opening of the clamp 121, the arcuate support member 108 and the lens 100, to adjust the distance between the feed unit 120 and the center of the lens 100 to achieve the desired beamwidth and gain such as discussed with respect to
In addition, the second clamp 122 is releasably locked to the arcuate support member 108. The second clamp 122 can be placed in the unlocked position so that the feed unit 120 can slide circumferentially, i.e., up and/or down (longitudinally extending from the top to the bottom in the embodiment shown; i.e., in a polar plane or direction) along the arcuate support member 108 with respect to the lens 100, to adjust the relative position of the feed unit 120 to the lens 100.
In addition, the arcuate support member 108 can be rotated with respect to the lens 100 about the first and second rotating connections, i.e. laterally from left to right in the embodiment shown (i.e., in an equatorial plane or direction), and can partially or completely circumnavigate the spherical lens 100. The rotating connections can have a locked position and an unlocked position, and can be placed in the unlocked position to allow the support member 108 to be rotated, and in the locked position to prevent rotation and lock the feed unit 120 and support member 108 at the desired position with respect to the lens 100. As best illustrated in
Thus, the feed unit 120 can be adjusted to any position on the lens 100 via the first coupling mechanism (e.g., the arcuate support member 108 to move in the phi-direction, i.e., in an equatorial direction or plane (left/right in the embodiments shown)) and second coupling mechanism (e.g., the second clamp 122 to move in the theta-direction, i.e., in a polar direction or plane (up/down)), and at any distance to the lens via the third coupling mechanism (e.g., the first clamp 121 to move in the r-direction, i.e., in a radial direction (in/out)). Each of the coupling mechanisms releasably lock the feed unit to the spherical lens. The clamps 121, 122 may be separate components or may be formed as a single integral piece or component, and can either be locked and unlocked separately or together (simultaneously), and can be operated manually or automatically such as by a motor. In yet another example embodiment, a single positioning device can be provided that simultaneously (manually or automatically) adjusts the radial, longitudinal and/or lateral positions of the feed unit 120.
In one embodiment the feed unit 120 comprises a waveguide, optionally provided with a horn or flange 124 at a first end and a waveguide-to-coaxial transition 123 at a second end having at least one coaxial connector 125, enabling radio signals from a donor feed unit to be connected by a coaxial cable to a corresponding service feed unit. Alternatively, the second end of feed unit 120 may be terminated with a waveguide flange to enable the connection of a length of waveguide between a donor feed unit and a corresponding service feed unit, such waveguide being preferably flexible or readily deformable. Waveguide 120 may have a rectangular cross section and support transmission and reception of plane-polarized signals, or may have a square or circular cross section, supporting the transmission and reception of dual-linear or circularly polarized signals.
In a further embodiment, the feed unit 120 may comprise a printed circuit antenna, for example an array of slot or patch radiating elements.
Mobile radio systems commonly employ dual slant linear polarization, so it is advantageous that feed units supporting donor and service beams, together with interconnecting transmission lines are configured to support dual slant linear polarization for both donor and service beams.
The arrangement herein described provides for improved adaption of a standard configuration of a repeater having lens antenna provided with inter-connected donor and service feed units to the specific requirements of individual practical use cases. In many use cases it may be necessary to optimize the configuration of each feed unit to provide the maximum possible gain available from the lens antenna; in other cases it may be desirable to obtain the maximum possible gain from a donor antenna while serving an area requiring a wider beamwidth from a service beam. The arrangement provided in this disclosure permits both objectives to be served by a standard repeater arrangement, reducing logistical requirements compared with an arrangement requiring physically different repeater antennas for different applications.
It will be understood that the arrangements described above for clamping a feed unit into position may be replaced with arrangements permitting the selection of the position for a feed unit to be controlled by actuators, for example stepper motors, operating under remote control, thereby enabling dynamic control of the coverage of the repeater,
A repeater configured according to the present disclosure may incorporate switching, routing, or passive radio frequency power division arrangements as described in U.S. Patent Application Ser. No. 62/914,063
A repeater configured according to the present disclosure is not limited in operation to any specific frequency band or radio transmission standard, for example it will operate with 5th-generation “5G NR” radio services or any future fixed or mobile radio transmission standard. Applications of the disclosure are not limited to the millimeter-wave frequency band but may for example extend from 10 GHz to 300 GHz. The range of frequencies over which any specific embodiment can operate is primarily dependent on the bandwidth of the feed unit(s) employed and on the bandwidth of any surface matching arrangements, for example grooves or dielectric layers applied to the lens. A lens repeater may be provided with pairs of feed units (one of each supporting a donor beam and the other a service beam) operating in different frequency bands,
It will be apparent to those skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings that modifications, combinations, sub-combinations, and variations can be made without departing from the spirit or scope of this disclosure, Likewise, the various examples described may be used individually or in combination with other examples. Those skilled in the art will appreciate various combinations of examples not specifically described or illustrated herein that are still within the scope of this disclosure. In this respect, it is to be understood that the disclosure is not limited to the specific examples set forth and the examples of the disclosure are intended to be illustrative, not limiting.
For example, it is noted that the example embodiments illustrate one way to adjustably move the feed unit in r, theta and phi-directions with respect to a polar coordinate system having its origin at the center of the spherical lens. However, other suitable mechanisms can be provided to move the feed unit, within the spirit and scope of the present disclosure.
As used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise. Similarly, the adjective “another,” when used to introduce an element, is intended to mean one or more elements. The terms “comprising,” “including,” “having” and similar terms are intended to be inclusive such that there may be additional elements other than the listed elements.
It is noted that the drawings may illustrate, and the description and claims may use geometric or relational terms, such as spherical, inward, outward, orthogonal, top, bottom, planar, cylindrical, arcuate, radially, circumferential, axially. These terms are not intended to limit the disclosure and, in general, are used for convenience to facilitate the description based on the examples shown in the figures. In addition, the geometric or relational terms may not be exact. For instance, the lens may not be exactly spherical because of local truncations to facilitate the attachment of mounting arrangements, or for example, roughness of surfaces, tolerances allowed in manufacturing, etc., but may still be considered to be spherical or sufficiently or substantially spherical to be utilized in the present disclosure.
This application claims the benefit of priority of U.S. Patent Application Ser. No. 62/914,063 filed on Oct. 11, 2019 and entitled “Highly Efficient Variable Beamwidth Lens Repeater,” the content of which is relied upon and incorporated herein by reference in its entirety.
Number | Date | Country | |
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62914063 | Oct 2019 | US |