TECHNICAL FIELD

The present disclosure relates generally to the field of antennas; and more specifically, to antenna systems and methods of feeding antenna arrays of dual-polarized radiating elements.

BACKGROUND

Typically, communication systems employ multiple antennas (where each antenna include one or more radiators) to perform massive multiple-input multiple-output (mMIMO). Often, an allowed size of a radiating structure (i.e. an aperture) is constrained. Moreover, it is known that increasing the number of antennas over the available aperture beyond a certain density is counterproductive. As this results in coupling of antennas, and radiation patterns become highly correlated, resulting in poorer performance of the communication systems.

Conventional antenna systems use a higher number of transceivers (i.e. transmitter/receiver (TRx) or radio chains) to introduce a higher flexibility in radiation pattern control in order to improve the performance of the antennas which use mMIMO. These transceivers are mapped onto the available radiators. Each of the transceivers usually feed a specific number of antenna elements in a conventional antenna array, and these groups of antenna elements are called sub arrays. In cases where the conventional antenna array is dual-polarized, each polarization of each sub array is fed together sharing the same antenna elements. However, as system performance of the communications system depends on the coupling between each transceiver on the antenna array, the system performance is degraded due to the use of higher number of transceivers. Thus, the technical problem is how to reduce the level of coupling in the antennas (i.e. in the conventional antenna array or antenna system) to improve the performance of the antenna system.

Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks associated with conventional antenna systems.

SUMMARY

The present disclosure seeks to provide an antenna system and a method of feeding an antenna array of dual-polarized radiating elements. The present disclosure seeks to provide a solution to the existing problem of coupling between transceivers in the antenna array, that reduces system performance of a conventional antenna system. An aim of the present disclosure is to provide a solution that overcomes at least partially the problems encountered in prior art and provides an improved structure of an antenna system in which coupling is reduced and system performance is improved.

The object of the present disclosure is achieved by the solutions provided in the enclosed independent claims. Advantageous implementations of the present disclosure are further defined in the dependent claims.

In one aspect, the present disclosure provides an antenna system, comprising: an antenna array of at least three dual-polarized radiating elements, wherein each of the dual-polarized radiating elements is configured to operate at a frequency range and comprises a first radiating part of a first polarization state and a second radiating part of a second polarization state orthogonal to the first polarization state, and a feeding structure connected with the dual-polarized radiating elements of each polarization state, wherein the feeding structure comprises: a first feeding network for feeding a first subarray of the dual-polarized radiating elements of the first polarization state by connecting with the first radiating parts of the dual-polarized radiating elements of the first subarray, and a second feeding network for feeding a second subarray of the dual-polarized radiating elements of the second polarization state by connecting with the second radiating parts of the dual-polarized radiating elements of the second subarray, wherein the second subarray is at least partially different from the first subarray.

The present disclosure provides an improved structure of the antenna system in which the first feeding network and the second feeding network are arranged in a way that there is increased distance between the feed lines of the feeding networks, and as a result of which there is reduced coupling (e.g. an improved feeding decoupling) in the antenna system. As the second subarray is at least partially different from the first subarray, this means that transceivers feed sub arrays that share radiating elements but not polarizations resulting in improved decoupling between transceivers. Moreover, the feeding lines are arranged alternately (e.g. to occupy reduced space in an antenna array) in the antenna system which results in higher integration in antenna routing in comparison to conventional antenna systems. Beneficially, the antenna system of the present disclosure provides an extra degree of freedom, for example, in radiation pattern shaping of the first and the second subarray, which further improves flexibility and system performance of the antenna system.

In an implementation form, the antenna array is a two-dimensional Massive Multiple Input Multiple Output (mMIMO) antenna array. Beneficially, even though the antenna system is mMIMO array, where multiple transceivers and dual-polarized radiating elements are used, still, the coupling between the transceivers is reduced and system performance is improved. In conventional and commercially available dual polarization mMIMO arrays, each pair of dual-polarized radiating elements or a triplet (i.e. three dual-polarized radiating elements) are fed by two transceivers (i.e. 2 TRxs), one for each polarization. In contradiction to the conventional dual polarization mMIMO arrays, in the antenna system of the present disclosure, one transceiver (TRx) feeds a subset of radiating elements (i.e. first subarray) of the same polarization, whereas another transceiver feeds a partially different subset of radiating elements (i.e. second subarray) on different polarization (e.g. orthogonal polarization), which significantly reduces coupling and improves system performance.

In a further implementation form, the dual-polarized radiating elements of each of the first and second subarrays are distributed horizontally and/or vertically in a top view.

By virtue of the first and second subarrays being distributed horizontally and/or vertically the antenna system of the present disclosure provides an extra degree of freedom in terms of radiation pattern shaping for the first and the second subarray, which further improves flexibility and system performance of the antenna system.

In a further implementation form, each of the first and second subarrays comprises three or more dual-polarized radiating elements.

The three or more dual-polarized radiating elements of the first and the second subarrays have an improved decoupling because of the the feeding structure in the antenna system. As a result, the radiation patterns are not correlated and there is improved system performance in comparison to conventional antennas.

In a further implementation form, the antenna system further comprising at least one singlepolarized radiating element arranged on at least one side of the antenna array.

By virtue of the at least one single polarized radiating element that is added at the top and bottom of the antenna array, a pairing for all the dual-polarized radiating elements is potentially obtained. For example, at edges of the antenna array where some dual-polarized radiating elements are not paired, the at least one single polarized radiating element is provided for the pairing of all the dual-polarized radiating elements.

In a further implementation form, each of the radiating elements comprises a patch antenna. The patch antenna is a flat radiating patch by virtue of which a large number of radiating elements can be used in a limited space of an antenna system (or an antenna array) and due to the feeding structure for these patch antennas, an improved decoupling is achieved.

In a further implementation form, each of the radiating elements comprises a director.

By virtue of the director, the dual-polarized radiating elements increase directivity of electromagnetic radiations that are transmitted or received in a given direction to maintain the system performance.

In another aspect, the present disclosure provides a method of feeding an antenna array of dual-polarized radiating elements, wherein the antenna array comprises at least three dualpolarized radiating elements, each of the dual-polarized radiating elements is configured to operate at a frequency range and comprises a first radiating part of a first polarization state and a second radiating part of a second polarization state orthogonal to the first polarization state, the method comprising: feeding, with a first feeding network, a first subarray of the dualpolarized radiating elements of the first polarization state by connecting the first feeding network with the first radiating parts of the dual-polarized radiating elements of the first subarray, and feeding, with a second feeding network, a second subarray of the dual-polarized radiating elements of the second polarization state by connecting the second feeding network with the second radiating parts of the dual-polarized radiating elements of the second subarray, wherein the second subarray is at least partially different from the first subarray.

The present disclosure provides an improved method of feeding the antenna array in which there is an increased distance between the feed lines of the first and the second feeding networks, resulting in reduced coupling in the antenna array (i.e. an improved feeding decoupling). Moreover, the method enables feeding via the feeding lines that are arranged alternately which results in higher integration in antenna routing in comparison to conventional antennas. Beneficially, the method of the present disclosure provides an extra degree of freedom in terms of radiation pattern shaping for the first and the second subarray which further improves performance of the antenna array.

It is to be appreciated that all the aforementioned implementation forms can be combined.

It has to be noted that all devices, elements, circuitry, units and means described in the present application could be implemented in the software or hardware elements or any kind of combination thereof. All steps which are performed by the various entities described in the present application as well as the functionalities described to be performed by the various entities are intended to mean that the respective entity is adapted to or configured to perform the respective steps and functionalities. Even if, in the following description of specific embodiments, a specific functionality or step to be performed by external entities is not reflected in the description of a specific detailed element of that entity which performs that specific step or functionality, it should be clear for a skilled person that these methods and functionalities can be implemented in respective software or hardware elements, or any kind of combination thereof. It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.

Additional aspects, advantages, features and objects of the present disclosure would be made apparent from the drawings and the detailed description of the illustrative implementations construed in conjunction with the appended claims that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.

Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:

FIG. 1A is an illustration of a portion of an antenna array of an antenna system, in accordance with an embodiment of the present disclosure;

FIG. 1 B is an illustration of an antenna system, in accordance with an embodiment of the present disclosure;

FIG. 1C is an illustration of an antenna system, in accordance with another embodiment of the present disclosure;

FIG. 1 D is an illustration of an antenna system, in accordance with yet another embodiment of the present disclosure;

FIG. 2 is a flowchart of a method of feeding an antenna array of dual-polarized radiating elements, in accordance with an embodiment of the present disclosure;

FIG. 3 is an illustration of an antenna system and an antenna array, in accordance with an embodiment of the present disclosure; FIG. 4A is an illustration of an implementation of a portion of an antenna system, in accordance with an embodiment of the present disclosure;

FIG. 4B is an illustration of an implementation of a portion of an antenna system, in accordance with another embodiment of the present disclosure;

FIG. 4C is an illustration of an implementation of a portion of an antenna system, in accordance with yet another embodiment of the present disclosure;

FIG. 4D is an illustration of an implementation of a portion of an antenna system, in accordance with another embodiment of the present disclosure;

FIG. 5A is an illustration of an antenna system operating in a first polarization state, in accordance with an embodiment of the present disclosure;

FIG. 5B is an illustration of an antenna system operating in a second polarization state, in accordance with an embodiment of the present disclosure; and

FIG. 5C is an illustration of an antenna system operating in a first and a second polarization state, in accordance with an embodiment of the present disclosure.

In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the nonunderlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.

DETAILED DESCRIPTION OF EMBODIMENTS

The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.

FIG. 1A is an illustration of a portion of an antenna array of an antenna system, in accordance with an embodiment of the present disclosure. With reference to FIG. 1A, there is shown a portion of an antenna array 102 of an antenna system. In the FIG. 1A, in the portion of the antenna array 102, there is shown four dual-polarized radiating elements (such as the dualpolarized radiating element 104) and a feeding structure 106 connected with the dual-polarized radiating elements 104. Each of the dual-polarized radiating elements 104 includes a first radiating part 108 and a second radiating part 110. The feeding structure 106 includes a first feeding network 112 and a second feeding network 114. There is shown a first subarray 116 and a second subarray 118. Further, there is shown transceivers 120 connected to each of the first feeding network 112 and the second feeding network 114. In the FIG. 1A, it is to be understood that the dashed squares that represents the first subarray 116 and the second subarray 118, are used for illustration purpose only, and do not form a part of the antenna array 102. Moreover, for illustration purposes, thick lines are used to represent the first feeding network 112 for one polarization state (i.e. the first polarization state) and dotted lines are used to represent the second feeding network 114 for another polarization state (i.e. the second polarization state), where both the first feeding network 112 and the second feeding network 114 are electrically conductive tracks.

In one aspect, the present disclosure provides the antenna system comprising: an antenna array 102 of at least three dual-polarized radiating elements, wherein each of the dual-polarized radiating elements 104 is configured to operate at a frequency range and comprises a first radiating part 108 of a first polarization state and a second radiating part 110 of a second polarization state orthogonal to the first polarization state, and a feeding structure 106 connected with the dual-polarized radiating elements 104 of each polarization state, wherein the feeding structure 106 comprises a first feeding network 112 for feeding a first subarray 116 of the dualpolarized radiating elements 104 of the first polarization state by connecting with the first radiating parts 108 of the dual-polarized radiating elements 104 of the first subarray 116, and a second feeding network 114 for feeding a second subarray 118 of the dual-polarized radiating elements 104 of the second polarization state by connecting with the second radiating parts 110 of the dual-polarized radiating elements 104 of the second subarray 118, wherein the second subarray 118 is at least partially different from the first subarray 116.

The antenna array 102 of the antenna system may also be referred to as an antenna panel or an array comprising several antenna elements (i.e. multiple antenna devices, radiating elements, or radiators arranged in a defined manner). The antenna system is used for telecommunication. For example, the antenna system may be used in a wireless communication system. In some embodiments, an array of such antenna system or one or more antenna systems, may be used in the communication system. Examples of such wireless communication system include, but is not limited to, a base station (such as an Evolved Node B (eNB), a gNB, and the like), a repeater device, a customer premise equipment, and other customized telecommunication hardware. In an implementation, the radiating side of the antenna array 102 may have a non-planar structure. It is to be understood by one of ordinary skill in the art that the antenna array 102 of the system may have different geometrical shapes, such as elongated, square, rectangular, circular, or even planar structure, without limiting the scope of the disclosure. The antenna array 102 refers to a combination of two or more dual-polarized radiating elements 104 that may be arranged horizontally or vertically or in a combination of horizontal and vertical to enable wireless communication.

According to an embodiment, the antenna array 102 is a two-dimensional Massive Multiple Input Multiple Output (mMIMO) antenna array. The antenna system is configured to use the MIMO or multi-user MIMO (MU-MIMO), or massive MIMO methods for transmission or receiving of radio frequency signals via the dual-polarized radiating elements 104 to and from various network nodes, such as user equipment devices or base station simultaneously. The antenna system supports MIMO to achieve spectral efficiency for communication with the UEs. Beneficially, even though the antenna array 102 is the mMIMO array, where multiple transceivers 120 and dualpolarized radiating elements 104 are used, still, the coupling between the transceivers 120 is reduced and the overall system performance is improved.

The dual-polarized radiating elements 104 may also be referred to as antenna elements, and are configured to transmit and receive communication signals (such as radio frequency signals) to and from devices, such as UEs. In an example, the dual-polarized radiating elements 104 receive radio frequency current from the feeding structure 106 to enable transmission and receiving of radio frequency signals. The dual-polarized radiating elements 104 may be configured to operate as an uplink element or a downlink element. In an example, the dualpolarized radiating elements 104 alternatively operate as uplink and downlink elements.

According to an embodiment, each of the radiating elements 104 comprises a director. The director enables the dual-polarized radiating elements 104 to increase a directivity of the electromagnetic signals/radiations that are transmitted or received in a given direction. As a result, a beam of RF signals can be formed in a given direction by the dual-polarized radiating elements 104 using the director.

Each of the dual-polarized radiating elements 104 is configured to operate at a frequency range. The frequency range refers to range in which communication signals are transmitted or received by the dual-polarized radiating elements 104. In an example the frequency range may be a 5G New Radio (NR) radio frequency range (e.g. F1 band of sub-6 Ghz or a F2 band of above 6 GHz that constitute mmWave signals). In another example, the frequency range is 20 Kilohertz to 300 GHz.

The dual-polarized radiating elements 104 include the first radiating part 108 of the first polarization state and the second radiating part 110 of the second polarization state orthogonal to the first polarization state. By means of the first radiating part 108 and the second radiating part 110, each of the dual-polarized radiating elements 104 can transmit or receive two independent data streams. Beneficially, as the second polarization state is orthogonal to the first polarization state there is reduced interference between the two polarization states. In an example, there is reduced interference between the radio frequency signals transmitted or received by the first radiating part 108 and the second radiating part 110. In other words, a direction of electromagnetic signals transmitted by the two radiating parts are orthogonal with respect to each other.

According to an embodiment, each of the radiating elements 104 comprises a patch antenna. The patch antenna refers to a flat radiating patch that is configured to radiate electromagnetic signal in the frequency range. In an example, the radiating elements 104 in the form of the patch radiator has a top surface and a bottom surface wherein the electromagnetic signal in the frequency range is radiated from the top surface. In an implementation, the radiating elements 104 is a metallic patch radiator.

The feeding structure 106 is connected with the dual-polarized radiating elements 104 of each polarization state. The feeding structure 106 is configured to enable the first radiating part 108 and the second radiating part 110 to transmit or receive electromagnetic signals. As shown, the feeding structure 106 provides feed current to the first radiating part 108 and the second radiating part 110 of each of the dual-polarized radiating elements 104. In other words, the feeding structure 106 refers to conductive tracks that are arranged to provide feed current to the first radiating part 108 for the first polarization and the second radiating part 110 for the second polarization.

According to an embodiment, the first feeding network 112 and the second feeding network 114 of the feeding structure 106 are connected to a respective transceiver (also represented as TRx in the FIG. 1A). In an example, each of the transceivers 120 corresponds to a radio chain or is a part of the radio chain that is connected to each of the first feeding network 112 and the second feeding network 114. A radio chain refers to a single radio and all of its supporting signal processing electronic components, including a transceiver, one or more mixers, one or more amplifiers, and one or more analog/digital converters.

According to an embodiment, each of the first and second subarrays comprises at least a pair of the dual-polarized radiating elements 104. In other words, each of the first subarray 116 and the second subarray 118 include a pair of dual-polarized radiating elements 104. In an example, the first subarray 116 includes a first dual-polarized radiating element 104a and a second dual-polarized radiating element 104b, and the second subarray 118 includes the second dual-polarized radiating element 104b and a third dual-polarized radiating element 104c. In some embodiments, alternatively, each of the first and second subarrays comprises three or more dual-polarized radiating elements 104. In some implementations, each of the first subarray 116 and the second subarray 118 may include a triplet of dual-polarized radiating elements 104. Each of the transceivers 120 usually feed a specific number of antenna elements called subarrays. In conventional and commercially available dual polarization mMIMO arrays, each pair of dual-polarized radiating elements or a triplet (i.e. three dualpolarized radiating elements) are fed by two transceivers (i.e. 2 TRxs), one for each polarization. In contradiction to the conventional dual polarization mMIMO arrays, as shown in the antenna array 102 of the present disclosure, one transceiver (TRx) feeds a subset of radiating elements (i.e. the first subarray 116) of the same polarization, whereas another transceiver feeds a partially different subset of radiating elements (i.e. the second subarray 118) on different polarization (e.g. orthogonal polarization), which significantly reduces coupling and improves system performance.

The feeding structure 106 includes the first feeding network 112 for feeding the first subarray 116 of the dual-polarized radiating elements 104 of the first polarization state by connecting with the first radiating parts 108 of the dual-polarized radiating elements 104 of the first subarray 116. In an example, the first subarray 116 includes a first dual-polarized radiating element 104a and a second dual-polarized radiating element 104b of the dual-polarized radiating elements 104. In such a case, the first feeding network 112 feeds the first polarization state of both the first dual-polarized radiating element 104a and the second dualpolarized radiating element 104b by connecting to respective first radiating parts 108.

According to an embodiment, a first transceiver 120a of the transceivers 120 is connected to second feeding network 114 that provides feed current to the first polarization state of the dual-polarized radiating elements 104 of the first subarray 116.

The feeding structure 106 further includes the second feeding network 114 for feeding the second subarray 118 of the dual-polarized radiating elements 104 of the second polarization state by connecting with the second radiating parts 110 of the second subarray 118. In an example, the second subarray 118 includes the second dual-polarized radiating element 104b and the third dual-polarized radiating element 104c of the dual-polarized radiating elements 104. In such a case, the second feeding network 114 feeds the second polarization state of both the second dual-polarized radiating element 104b and the third dual-polarized radiating element 104c by connecting to respective second radiating part 110. According to an embodiment, a second transceiver 120b of the transceivers 120 is connected to the first feeding network 112 that provides feed current to the second polarization state of dual-polarized radiating elements 104 of the second subarray 118.

The various transceivers 120 feed the sub arrays (via the first feeding network 112 and the second feeding network 114) that share dual-polarized radiating elements 104 but not polarization states. In an example, each dual-polarized radiating elements 104 has two polarization states (i.e. first polarization state and the second polarization state) such that first polarization state is fed by one transceiver such as a transceiver ‘A’ and second polarization state will be fed by another transceiver such as a transceiver ‘B’. This reduces coupling between transceivers and improves system performance.

The second subarray 118 is at least partially different from the first subarray 116. In other words, first subarray 116 and the second subarray 118 have at least one common dualpolarized radiating element (e.g. the dual-polarized radiating elements 104b) and at least one dual-polarized radiating element (e.g. the dual-polarized radiating element 104a or the dualpolarized radiating element 104c) that is different in each subarray. Alternatively stated, the first subarray 116 includes the first dual-polarized radiating element 104a and the second dualpolarized radiating element 104b, and the second subarray 118 includes the second dualpolarized radiating element 104b that is common and the third dual-polarized radiating element 104c that is different. Thus, in this example the second subarray 118 is at least partially different.

In comparison to the conventional antenna systems in which the first subarray 116 and the second subarray 118 completely overlap with each other, the antenna system of the present disclosure has reduced coupling between the various transceivers 120 in comparison to the antenna system used conventionally. In an example, a level of co-polar coupling and x-polar coupling in conventional antenna systems are higher and is substantially reduced by the antenna system of the present disclosure. The coupling between the transceivers 120 can limit performance and therefore capacity provided by the antenna system. It is therefore important to control and reduce the level of coupling, which is achieved by the antenna system of the present disclosure.

As the dual-polarized radiating elements 104 are very close together in the antenna system of the present disclosure as well as in conventional antenna systems, routing may be challenging due to the reduce space, which may lead to high coupling. Thus, in the antenna system of the present disclosure, the first feeding network 112 and the second feeding network 114 are arranged in a way that, there is increased distance between the feed lines of the feeding networks to reduce the coupling. As a result, a phase center of the first subarray 116 and the second subarray 118 is displaced in comparison to conventional antenna systems. As polarization coupling is inversely proportional to the distance, an increase in the aforesaid distance reduced the polarization coupling in comparison to conventional antenna systems. Beneficially, the antenna system having the antenna array 102 provides an extra degree of freedom on setting transceivers configurations. In an example, the antenna system allows a highly decoupled vertical or horizontal configuration of transceivers.

FIG. 1 B is an illustration of an antenna system, in accordance with an embodiment of the present disclosure. FIG. 1B is described in conjunction with elements from FIG. 1A. With reference to FIG. 1 B, there is shown an antenna system 122A. The antenna system 122A includes the dual-polarized radiating elements 104, each of which includes the first radiating part 108 and the second radiating part 110. There is shown the first feeding network 112 and the second feeding network 114. There is further shown the first subarray 116 and the second subarray 118. Further, there is shown transceivers 120 connected to each of the first feeding network 112 and the second feeding network 114.

The antenna system 122A includes the antenna array 102 described in FIG. 1A that are operating together in the antenna system 122A. In the antenna system 122A, the first feeding network 112 and the second feeding network 114 are arranged vertically.

According to an embodiment, the dual-polarized radiating elements 104 of each of the first and second subarrays are distributed vertically in a top view. In an example, three dual-polarized radiating elements 104 of the first subarray 116 and the second subarray 118 are arranged vertically in a way that the first dual-polarized radiating element 104a is above the second dual-polarized radiating element 104b, and the third dual-polarized radiating element 104c is below the second dual-polarized radiating element 104b.

The first subarray 116 and the second subarray 118 are vertically arranged with an overlap between them. In other words, both the first subarray 116 and the second subarray 118 have one dual-polarized radiating element in common.

In the antenna system 122A, the distance D between two feeding lines of a given feeding network (such as first feeding network 112) is larger in comparison to feeding lines of conventional antenna systems. As a result, an improved routing of the transceivers 120 is enabled. Moreover, the first feeding network 112 and the second feeding network 114 may not be parallel to each other, as a result of which better integration is enabled in comparison to conventional antenna systems. Beneficially, the antenna system 122A has improved decoupling between transceivers 120 proportional to the distance D that is increased with reference to their respective phase centers. Moreover, higher integration is possible in the routing as feeding lines of a given feeding network alternate to occupy space (horizontally). Moreover, an improved feeding decoupling is possible since the feeding lines are distributed over a larger area in comparison to conventional antenna systems where feeding lines are close by leading to coupling. The terms vertical and horizontal refers to directions with respect to ground surface (considering earth’s surface as horizontal surface) when the antenna system 122A is deployed.

FIG. 1C is an illustration of an antenna system, in accordance with another embodiment of the present disclosure. FIG. 1C is described in conjunction with elements from FIG. 1A and 1 B. With reference to FIG. 1 C, there is shown an antenna system 122B. The antenna system 122B includes the dual-polarized radiating elements 104, each of which includes the first radiating part 108 and the second radiating part 110. There is shown the first feeding network 112 and the second feeding network 114. There is further shown the first subarray 116 and the second subarray 118. Further, there is shown transceivers 120 connected to each of the first feeding network 112 and the second feeding network 114.

In the antenna system 122B the first feeding network 112 is arranged vertically and the second feeding network 114 is arranged horizontally. The first subarray 116 is arranged vertically and the second subarray 118 are horizontally arranged with an overlap between them. In other words, both the first subarray 116 and the second subarray 118 have one dualpolarized radiating element in common. The first subarray 116 and the second subarray 118 are connected to the first feeding network 112 that is arranged vertically and the second feeding network 114 that is arranged horizontally. The antenna system 122B has similar advantage as that of the antenna system 122A.

According to an embodiment, the dual-polarized radiating elements 104 of each of the first and second subarrays are distributed vertically and horizontally respectively in a top view. In an example, three dual-polarized radiating elements 104 are potentially arranged horizontally and vertically such that a first dual-polarized radiating element 104a is arranged above a second dual-polarized radiating element 104b, and a third dual-polarized radiating element 104c is arranged right to the second dual-polarized radiating element.

FIG. 1 D is an illustration of an antenna system, in accordance with yet another embodiment of the present disclosure. FIG. 1 D is described in conjunction with elements from FIG. 1A, 1 B, and 1C. With reference to FIG. 1 D, there is shown an antenna system 122C. The antenna system 122C includes the dual-polarized radiating elements 104, each of which includes the first radiating part 108 and the second radiating part 110. There is shown the first feeding network 112 and the second feeding network 114. There is further shown the first subarray 116 and the second subarray 118. Further, there is shown transceivers 120 connected to each of the first feeding network 112 and the second feeding network 114.

In the antenna system 122C, the first feeding network 112 is alternatively arranged vertically and horizontally. Further, the second feeding network 114 is also alternatively arranged horizontally and vertically. Thereby, the first subarray 116 is alternatively arranged vertically and horizontally. Further, the second subarray 118 is also alternatively arranged horizontally and vertically. Beneficially, the combination of arranging the feeding networks horizontally and vertically provides extra freedom in terms of subarray’s radiation pattern shaping, which leads to an increase in system performance of the antenna system 122C. In other words, a combination of vertical and horizontal pairs of the same polarization enables extra freedom in terms of the subarray’s radiation pattern shaping, which can lead to an increase in the system performance. The antenna system 122C has similar advantage as that of the antenna system 122A.

According to an embodiment, the dual-polarized radiating elements 104 of each of the first and second subarrays are alternatively distributed vertically and horizontally in a top view. In an example, two or three dual-polarized radiating elements 104 are arranged horizontally and vertically such that the first dual-polarized radiating element 104a is arranged below the second dual-polarized radiating element 104b, and the third dual-polarized radiating element 104c is arranged right to the second dual-polarized radiating element 104b, as shown.

FIG. 2 is a flowchart of a method of feeding an antenna array of dual-polarized radiating elements, in accordance with an embodiment of the present disclosure. FIG. 2 is described in conjunction with elements from FIG. 1A, 1B, and 1C. In another aspect, the present disclosure provides a method of feeding an antenna array 102 of dual-polarized radiating elements 104, wherein the antenna array 102 comprises at least three dual-polarized radiating elements, each of the dual-polarized radiating elements 104 is configured to operate at a frequency range and comprises a first radiating part 108 of a first polarization state and a second radiating part 110 of a second polarization state orthogonal to the first polarization state, the method comprising: feeding, with a first feeding network 112, a first subarray 116 of the dualpolarized radiating elements 104 of the first polarization state by connecting the first feeding network 112 with the first radiating parts 108 of the dual-polarized radiating elements 104 of the first subarray 116, and feeding, with a second feeding network, a second subarray 118 of the dual-polarized radiating elements of the second polarization state 104 by connecting the second feeding network with the second radiating parts 110 of the dual-polarized radiating elements 104 of the second subarray 118, wherein the second subarray 118 is at least partially different from the first subarray 116.

The method 200 includes steps 202 and 204. The steps 202 and 204 may be executed in any reasonable order to carry into effect the objectives of the disclosed embodiments. No particular order to the disclosed steps of the method 200 is necessarily implied by the depiction in FIG. 2, and the accompanying description, except where a particular method step is a necessary precondition to execution of any other method step. Individual method steps may be carried out in sequence or in parallel in simultaneous or near simultaneous timing.

At step 202, the method 200 comprises feeding, with a first feeding network 112, a first subarray 116 of the dual-polarized radiating elements 104 of the first polarization state by connecting the first feeding network 112 with the first radiating parts 108 of the dual-polarized radiating elements 104 of the first subarray 116. The first feeding network 112 provides feed to the first radiating parts 108 of the dual-polarized radiating elements to enable the dualpolarized radiating elements 104 to transmit or receive two independent data streams. In an example, the first feeding network 112 includes feed lines to provide feed to the dual-polarized radiating elements 104. In an example, the first feeding network 112 feeds the first polarization state of both a first dual-polarized radiating element 104a and a second dual-polarized radiating element 104b of the dual-polarized radiating elements 104 by connecting to the respective first radiating parts 108.

According to an embodiment, the first feeding network is connected to transceivers 120 to provide feed to the dual-polarized radiating elements 104 of the first subarray 116.

At step 204, the method 200 comprises feeding, with a second feeding network 114, a second subarray 118 of the dual-polarized radiating elements 104 of the second polarization state by connecting the second feeding network with the second radiating parts 110 of the dualpolarized radiating elements 104 of the second subarray 118, wherein the second subarray 118 is at least partially different from the first subarray 116. The second feeding network 114 provides feed to the second radiating parts 110 of the dual-polarized radiating elements 104to enable the dual-polarized radiating elements 104 to transmit or receive two independent data streams. In an example, the second feeding network 114 includes feed lines to provide feed to the dual-polarized radiating elements 104. In an example, the second feeding network 114 feeds the second polarization state of both the second dual-polarized radiating 104b element and a third dual-polarized radiating element 104c of the dual-polarized radiating elements 104 by connecting to the respective second radiating parts 110. Moreover, a phase center of the first sub array 116 and the second subarray 118 is displaced in comparison to conventional antenna systems. Thus, as polarization coupling is inversely proportional to the distance, an increase in the aforesaid distance reduced the polarization coupling in comparison to conventional technologies. Beneficially, the antenna system of the present disclosure provides an extra degree of freedom on setting transceiver configurations. In an example, the antenna system allows a highly decoupled vertical or horizontal configuration of transceiver.

Beneficially, as the second subarray 118 is partially different from the first subarray 116 there is reduced coupling between the transceivers in comparison to the antenna system used conventionally. The reduced coupling enables in providing improved system performance by the antenna system.

The steps 202 and 204 are only illustrative and other alternatives can also be provided where one or more steps are added, one or more steps are removed, or one or more steps are provided in a different sequence without departing from the scope of the claims herein.

FIG. 3 is an illustration of an antenna system and an antenna array, in accordance with an embodiment of the present disclosure. With reference to FIG. 3, there is shown the antenna system 300 and an antenna array 302 of the antenna system 300. The antenna system 300 includes dual-polarized radiating elements, such as uplink elements 304 and downlink elements 306. The antenna system 300 further includes single polarized radiating elements as uplink single elements 308 and downlink single elements 310.

The antenna array 302 includes interleaved dual-polarized radiating elements and single polarized radiating elements at edges, working at different bands. The antenna array 302 includes feeding network that via feed lines provide feed to the uplink elements 304, the downlink elements 306, the uplink single elements 308 and the downlink single elements 310. In an example, at least two uplink elements are jointly fed (connected to) by one port for uplink and for communicating RF signals at the first polarization state at one side of the antenna array 302 (represented as “pol+” i.e. polarization at one side of the antenna array 302).

Similarly, at least two downlink elements are jointly fed (connected to) by one port for downlink and for communicating RF signals at the second polarization state at the other side (represented as “pol-” i.e. polarization at another side of the antenna array 302). In an example, different ports (Portl, port2, port3, port4) are provided, each of which are connected to two respective uplink and downlink elements of different polarization states via respective feed lines, as shown. As shown, the routing of feed lines of the feeding network is very convoluted, which improves the antenna performance. Additionally, the single polarized element (uplink single elements 308 and downlink single elements 310) is added at the top and bottom of the antenna array 302 to have pairing for all the dual-polarized radiating elements. The uplink single element 308 is paired with one uplink element 304 and the downlink single element 310 is paired with one downlink element 306. Thus, the antenna system 300 has reduced coupling and improved feeding of the dual-polarized radiating elements. The antenna system 300 may be a dual band mMIMO array.

In some embodiments, the antenna system further comprising at least one single-polarized radiating element arranged on at least one side of the antenna array. The at least one single polarized radiating element (represented as the uplink single elements 308 and the downlink single elements 310) is added at the top and bottom of the antenna array 302 to have pairing for all the dual-polarized radiating elements. The single polarized radiating element is connected to a transceiver that feeds only to one dual-polarized radiating element at the top and the bottom of the antenna array 302. Thus, the antenna array 302 provides an improved structure such that there is increased distance between the feed lines of the feeding networks, and as a result of which there is reduced coupling (e.g. an improved feeding decoupling) in the antenna system 300.

FIG. 4A is an illustration of an implementation of a portion of an antenna system, in accordance with an embodiment of the present disclosure. With reference to FIG. 4A, there is shown the antenna system 400A.

The antenna system 400A includes dual-polarized radiating elements, such as an uplink element 402A, and a downlink element 404A. The antenna system 400A further includes a first feeding network 406A and a second feeding network 408A. The antenna system 400A provides a wider antenna array to make space for the feeding lines connecting the dualpolarized radiating elements.

FIG. 4B is an illustration of an implementation of a portion of an antenna system, in accordance with another embodiment of the present disclosure. With reference to FIG. 4B, there is shown the antenna system 400B. The antenna system 400B includes dual-polarized radiating elements, such as an uplink element 402B, and a downlink element 404B. The antenna system 400B further includes a first feeding network 406B and a second feeding network 408B. As shown, each of the first feeding network 406B and the second feeding network 408B have two feed lines which have space between them. However, the antenna system 400B has coupling (crosstalk) between the two feed lines of each of the first feeding network 406B and the second feeding network 408B. FIG. 4C is an illustration of an implementation of a portion of an antenna system, in accordance with yet another embodiment of the present disclosure. With reference to FIG. 4C, there is shown the antenna system 400C. The antenna system 400C includes dual-polarized radiating elements, such as an uplink element 402C, and a downlink element 404C. The antenna system 400B further includes a first feeding network 406C and a second feeding network 408C. As shown, each of the first feeding network 406C and the second feeding network 408C have feed lines which cross each other. As a result, the antenna system 400C has some coupling (crosstalk) between the feed lines of each of the first feeding network 406C and the second feeding network 408C.

FIG. 4D is an illustration of an implementation of a portion of an antenna system, in accordance with another embodiment of the present disclosure. With reference to FIG. 4D, there is shown the antenna system 400C. The antenna system 400D includes dual-polarized radiating elements, such as an uplink element 402D and a downlink element 404D. The antenna system 400B further includes a first feeding network 406D and a second feeding network 408D. As shown, the antenna system 400D has a compact structure. Beneficially, there is no crossover and coupling between feeding lines of the first feeding network 406D and the second feeding network 408D in this arrangement of feeding network.

FIG. 5A is an illustration of an antenna system operating in first polarization state, in accordance with an embodiment of the present disclosure. With reference to FIG. 5A, there is shown the antenna system 500A. The antenna system 500A includes an antenna array 502 (as column), where the antenna system 500A corresponds to the antenna system 300 with the antenna array 302 (of FIG. 3) to depict routing of feed lines for dual-polarized radiating elements (uplink elements 504 and downlink elements 506), where a transceiver shares radiating elements but not polarization. Specifically, in the FIG. 5A, there are shown slots and the routing of the feed lines for slots, where the slots are for feeding the dual-polarized radiating elements (i.e. patch elements) of the antenna system 300 (of FIG. 3).

In contradiction to the conventional dual polarization mMIMO arrays, in the antenna system 500A of the present disclosure, one transceiver (TRx) feeds a subset of dual-polarized radiating elements (i.e. first subarray) of the same polarization, whereas another transceiver feeds a partially different subset of dual-polarized radiating elements (i.e. second subarray) on different polarization (e.g. orthogonal polarization), which significantly reduces coupling and improves system performance. In the FIG. 5A, in the antenna system 500A, there is shown a representative group of three dual-polarized radiating elements, which includes two downlink elements and one uplink element, using rounded rectangles (e.g. a representation 514 that depicts one group) for illustration purposes, which communicate RF signals in a first polarization state.

Moreover, for illustration purposes, in the antenna system 500A, different feeding networks for each subset of radiating elements are illustrated, where the different feeding networks are arranged alternatively in a way that there is increased distance between the feed lines of the feeding networks to reduce the coupling. In this case, for example, feeding lines of a first feeding network 510 and a second feeding network 512 is arranged alternatively to increase a distance between the feed lines (similar to that of FIG. 4D). Moreover, a distance with reference to respective phase centres is increased which improves decoupling between transceivers proportional to the distance that is increased. A phase center of feeding lines is displaced (e.g. in a defined phase offset 508). In an example, the defined phase offset 508 added in the feeding path is due to the direction in which a given slot is fed (where the slot feeds in turn a corresponding patch). As polarization coupling is inversely proportional to the distance, an increase in the aforesaid distance reduces the polarization coupling in comparison to conventional antenna systems. Beneficially, the defined phase offset 508 also provides an improved isolation.

FIG. 5B is an illustration of an antenna system operating in second polarization state, in accordance with an embodiment of the present disclosure. FIG. 5B is described in conjunction with elements from FIG. 5A. With reference to FIG. 5B, there is shown the antenna system 500A with another representative groups of three dual-polarized radiating elements, which includes two downlink elements and one uplink element (illustrated using rounded rectangles, such as a representation 516) for illustration purposes, which communicate RF signals in a second polarization state instead of the first polarization state of the FIG. 5A. In the FIG. 5B, each representative group (e.g. a representation 516 that depicts another group) of three dualpolarized radiating elements for the second polarization is partially different from the group of three dual-polarized radiating elements (e.g. the representation 514 of FIG. 5A) that operate in the first polarization. It is to be noted that the representative groups depicted by rounded rectangles (e.g. the representation 516) are used for illustration purposes only to depict active second polarization and are not used to indicate any feeding network. For example, in this case, there are pairs of dual-polarized radiating elements (each element corresponds to patch having two slots fed on different polarizations). In this case two downlink elements are connected and fed by a feed line, where another pair of uplink elements are connected and fed by another feed line, and where both these pairs are arranged alternatingly (i.e. an uplink element arranged between each pair of downlink elements relates to another pair and feeding network). An example of such arrangement has also been shown and described in FIG. 4D. FIG. 5C is an illustration of an antenna system operating in a first and a second polarization state, in accordance with an embodiment of the present disclosure. FIG. 5C is described in conjunction with elements from FIG. 5A and 5B. With reference to FIG. 5C, there is shown the antenna system 500A that operates in both the first polarization state and the second polarization state with decoupled polarization. In the FIG 5C, different representations (illustrated using rounded rectangles) of three dual-polarized radiating elements, which includes two downlink elements and one uplink element are shown (i.e. the representations 514 and 516 of FIG. 5A and 5B shown together) to illustrate communication of RF signals in both first and second polarization state. Each representative group (e.g. depicted by the representation 516) of three dual-polarized radiating elements for the second polarization is partially different from the representative group of three dual-polarized radiating elements (e.g. depicted by the representation 514) that operate in the first polarization for decoupled polarization, which significantly reduces coupling and improves system performance. In other words, transceivers feed subarrays that share radiating elements but not polarizations resulting in improved decoupling between transceivers due to their feeding structure.

In various embodiments of the antenna array (e.g. the antenna array 102, 302, 502) an improved antenna architecture is provided that manifests increased distance between the feed lines of the feeding networks, and as a result of which there is reduced coupling (e.g. an improved feeding decoupling) in the antenna system.

Modifications to embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as "including", "comprising", "incorporating", "have", "is" used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural. The word "exemplary" is used herein to mean "serving as an example, instance or illustration". Any embodiment described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments and/or to exclude the incorporation of features from other embodiments. The word "optionally" is used herein to mean "is provided in some embodiments and not provided in other embodiments". It is appreciated that certain features of the present disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the present disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable combination or as suitable in any other described embodiment of the disclosure.