Communication using a dual polarized antenna array

Abstract

Mechanisms are provided for communicating in a wireless access network using a dual-polarized antenna array. The antenna array includes antenna elements of a first polarization and a second polarization. A method includes transmitting a first signal on a first link of the wireless access network via a transmit antenna port in a transmit beam. The transmit antenna port is connected to antenna elements of both the first polarization and the second polarization. The method includes receiving a second signal on a second link of the wireless access network via a first receive antenna port in a first receive beam and via a second receive antenna port in a second receive beam. The first receive antenna port is connected to antenna elements of the first polarization and the second receive antenna port is connected to antenna elements of the second polarization. The receive beams and the transmit beam satisfy an overlap criterion with respect to their total power patterns.

Description

TECHNICAL FIELD

[0001] Embodiments presented herein relate to a method, an antenna array control unit, a computer program and a computer program product for communicating in a wireless access network using a dual-polarized antenna array. BACKGROUND

[0002] In a communication network, it can be challenging to obtain good performance and capacity for a given communication protocol, its parameters and the physical environment in which the communication network is deployed.

[0003] For example, for future generations of mobile communication networks, frequency bands at many different carrier frequencies can be needed. For example, some low frequency bands can be needed to achieve sufficient network coverage for wireless devices, and higher frequency bands (e.g. millimeter wave, mmW, i.e. close to and above 30 GHz) can be needed to obtain the needed network capacity. Typically, the propagation properties of radio channels on high frequencies are more challenging and can require beamforming at both the access node at the network side and the user node at the user side to obtain sufficient link budget.

[0004] At mmW frequencies, the beams generated by a planar antenna can be very narrow, forming so-called pencil beams. This can be necessary for sufficient data transmission / reception (Tx / Rx) performance. However, transmitting cell-defining reference signals, such as synchronization signal blocks (SSBs), using such narrow beams can result in large delays in initial network access, mobility and beam management procedures. This is because a large number of narrow beams are needed to cover a cell. Thus, finding the best narrow beam can take a long time. Therefore, at least sometimes wider beams are used to transmit cell-defining reference signals.

[0005] However, it can be difficult to generate such wide beams, and other beams, suitable for both signal transmission and reception. SUMMARY

[0006] It is an object of embodiments herein to provide techniques for efficiently generating wide beams, and other beams, suitable for both signal transmission and reception.

[0007] According to a first aspect, there is presented a method for communicating in a wireless access network using a dual-polarized antenna array. The antenna array comprises antenna elements of a first polarization and a second polarization. The method comprises transmitting a first signal on a first link of the wireless access network via a transmit antenna port in a transmit beam. The transmit antenna port is connected to antenna elements of both the first polarization and the second polarization. The method comprises receiving a second signal on a second link of the wireless access network via a first receive antenna port in a first receive beam and via a second receive antenna port in a second receive beam. The first receive antenna port is connected to antenna elements of the first polarization and the second receive antenna port is connected to antenna elements of the second polarization. The receive beams and the transmit beam 150a satisfy an overlap criterion regarding their total power patterns.

[0008] According to a second aspect, there is presented an antenna array control unit for communicating in a wireless access network using a dual-polarized antenna array. The antenna array comprises antenna elements of a first polarization and a second polarization. The antenna array control unit comprises processing circuitry. The processing circuitry is configured to cause the antenna array control unit to transmit a first signal on a first link of the wireless access network via a transmit antenna port in a transmit beam. The transmit antenna port is connected to antenna elements of both the first polarization and the second polarization. The processing circuitry is configured to cause the antenna array control unit to receive a second signal on a second link of the wireless access network via a first receive antenna port in a first receive beam and via a second receive antenna port in a second receive beam. The first receive antenna port is connected to antenna elements of the first polarization and the second receive antenna port is connected to antenna elements of the second polarization. The receive beams and the transmit beam satisfy an overlap criterion regarding their total power patterns.

[0009] According to a third aspect, there is presented an antenna array control unit for communicating in a wireless access network using a dual-polarized antenna array. The antenna array comprises antenna elements of a first polarization and a second polarization. The antenna array control unit comprises a transmitting module configured to transmit a first signal on a first link of the wireless access network via a transmit antenna port in a transmit beam. The transmit antenna port is connected to antenna elements of both the first polarization and the second polarization. The antenna array control unit comprises a receiving module configured to receive a second signal on a second link of the wireless access network via a first receive antenna port in a first receive beam and via a second receive antenna port in a second receive beam. The first receive antenna port is connected to antenna elements of the first polarization and the second receive antenna port is connected to antenna elements of the second polarization. The receive beams and the transmit beam satisfy an overlap criterion regarding their total power patterns.

[0010] According to a fourth aspect, there is presented a computer program for communicating in a wireless access network using a dual-polarized antenna array, the computer program comprising computer program code which, when run on an antenna array control unit, causes the antenna array control unit to perform the method according to the first aspect.

[0011] According to a fifth aspect, there is presented a computer program product comprising a computer program according to the fourth aspect and a computer readable storage medium on which the computer program is stored. The computer readable storage medium can be a non-transitory computer readable storage medium.

[0012] Advantageously, these aspects simplify the generation of wide beams and other beams applicable to both transmission and reception of signals.

[0013] Advantageously, using dual-polarized beamforming for transmission enables high power efficiency and low antenna gain fluctuation.

[0014] Advantageously, using single-polarized beamforming for reception enables polarization diversity.

[0015] Advantageously, these aspects enable the benefits of using dual-polarized beamforming for transmission to be combined with the benefits of using single-polarized beamforming for reception.

[0016] Advantageously, these aspects enable full output power to be used for transmission of reference signals while maintaining a match between beam shapes for transmission and reception.

[0017] Advantageously, these aspects enable two receive antenna ports with orthogonal polarizations to be used for diversity reception without any requirement that the receive antenna ports should be connected to antenna elements of both polarizations.

[0018] Advantageously, these aspects enable cell-defining reference signals to be transmitted in wide beams, resulting in increased cell coverage.

[0019] Other objects, features and advantages of the enclosed embodiments will become apparent from the following detailed description, the appended claims, and the accompanying drawings.

[0020] Generally, all terms used herein are to be interpreted according to their ordinary meaning in the technical field of the present disclosure, unless explicitly stated otherwise. All references to a / an / the item, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one and only one item, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed unless explicitly stated. BRIEF DESCRIPTION OF DRAWINGS

[0021] The inventive concept will now be described by way of example with reference to the accompanying drawings, in which:

[0022] Figure 1 This is a schematic diagram illustrating a wireless access network according to an embodiment;

[0023] Figure 2 A dual-polarized antenna array according to an embodiment is illustrated schematically;

[0024] Figure 3 This is a flowchart of the method according to the embodiment;

[0025] Figure 4 An example of the total power radiation pattern according to an embodiment is shown;

[0026] Figure 5 This is a schematic diagram showing the functional units of the antenna array control unit according to an embodiment;

[0027] Figure 6 This is a schematic diagram illustrating the functional modules of the antenna array control unit according to an embodiment;

[0028] Figure 7 An example of a computer program product including a computer-readable storage medium according to an embodiment is shown;

[0029] Figure 8 This is a schematic diagram illustrating a telecommunications network connected to a host computer via an intermediate network according to some embodiments; and

[0030] Figure 9 This is a schematic diagram illustrating a host computer communicating with a terminal device via a radio base station through a partially wireless connection, according to some embodiments. Detailed Implementation

[0031] The inventive concept will now be described more fully below with reference to the accompanying drawings, which illustrate certain embodiments of the inventive concept. However, the inventive concept can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Throughout the specification, similar reference numerals refer to similar elements. Any step or feature indicated by dashed lines should be considered optional.

[0032] The embodiments disclosed herein relate to a mechanism for communication in a wireless access network using a dual-polarized antenna array. To achieve this mechanism, an antenna array control unit, a method executed by the antenna array control unit, and a computer program product comprising code, for example, in the form of a computer program, which, when run on the antenna array control unit, causes the antenna array control unit to execute the method.

[0033] Figure 1 is a schematic diagram illustrating a wireless access network 100 in which embodiments presented herein can be applied. The wireless access network 100 can be a third generation (3G) telecommunication network, a fourth generation (4G) telecommunication network, a fifth generation (5G) telecommunication network or any evolution thereof, and support any 3GPP telecommunication standard, where applicable.

[0034] The wireless access network 100 comprises a (radio) access node 140 configured to provide network access to user nodes, as represented by a user node 160, in a (wireless) access network 110. The access network 110 is operatively connected to a core network 120. The core network 120 is in turn operatively connected to a service network 130, such as the Internet. The user node 160 is thereby able to access services of the service network 130 via the access node 140 and exchange data with the service network. The access node 140 and the user node 160 are configured to communicate with each other in beams 150a, 150b, 150c.

[0035] Examples of the access node 140 are a radio base station, a base transceiver station, a Node B, an evolved Node B, a gNB, an access point, an access node, and an integrated access backhaul node. Examples of the user node 160 are a wireless device, a terminal device, a mobile station, a mobile phone, a handset, a wireless local loop phone, a user equipment (UE), a smartphone, a laptop, a tablet computer, a network-equipped sensor, a network-equipped vehicle, a wearable electronic device, and a so-called Internet of Things device.

[0036] In this regard, a typical antenna architecture for a millimeter wave access node 140 consists of several antenna arrays directed in different directions. Some of the antenna arrays have orthogonally polarized antenna elements, enabling dual-polarized beamforming to be used. The access node 140 can then be configured to switch between different antenna arrays and / or within each antenna array when performing analog beamforming. However, in practical use, such an access node 140 can not use full power when transmitting in a wide beam. This can be due to some PAs being turned off or single-polarization with amplitude tapering being used. According to embodiments disclosed herein, the access node 140 can transmit in a wide beam while using full output power, thereby increasing coverage compared to using amplitude tapering or transmitting only on a subset of its antenna elements.

[0037] Figure 2 is a schematic diagram illustrating a dual-polarized antenna array 170, which can be part of a (radio) access node 140 or a user node 160, for example. Figure 2The dual-polarized antenna array 170 comprises antenna elements 172a of a first polarization and antenna elements 172b of a second polarization. The transceiver 180 accesses the dual-polarized antenna array 170 via a first panel port 182 and a second panel port 184. The first panel port 182 is connected to the antenna elements 172a of the first polarization via the feed network 174, while the second panel port 184 is connected to the antenna elements 172b of the second polarization via the feed network 174. Beamforming can be achieved by applying beamforming weights in the feed network 174, where the beamforming weights are applied by changing the gain values of the amplifiers 176 and the phase values of the phase shifters 178. In some examples, each antenna element 172a, 172b has its own amplifier 176 and phase shifter 178, which enables beamforming weights to be applied for each individual antenna element 172a, 172b. The beamforming weights, as well as the gain values and phase values, are controlled by an antenna array control unit 200, which is connected to the feed network 174 via a control interface 190.

[0038] As mentioned above, it can be difficult to generate such wide beams, as well as other beams, that are suitable for both transmission and reception of signals.

[0039] In this regard, for example, it is in principle possible to generate wider beams in two different ways: using single-polarization beamforming (SPBF) or using dual-polarization beamforming (DPBF).

[0040] For single-polarization beamforming, it is possible to widen the beam by applying an amplitude taper, which can also be a phase taper, on the antenna array of the panel antenna, where the taper is applied for each polarization. As recognized by the inventors, a drawback of this approach is that full power utilization for transmission cannot be obtained, since some antenna branches or elements need to transmit with reduced power (or attenuated if a common power amplifier (PA) is used) due to the amplitude taper. However, the inventors also recognize that the amplitude taper does not have the same negative impact on signal reception. The amplitude taper implies a reduction of the total transmit power, since not all antenna elements transmit with full power. In general, it is difficult to generate wide beams with high PA utilization and low gain fluctuation. As recognized by the inventors, the amplitude taper thus results in a loss of total transmit power and a reduction of the coverage of the cell-defining reference signal. Gain fluctuations in the beam transmitting the cell-defining reference signal can increase the risk of coverage holes in certain directions and can also cause more handover ping-pong effects during user node movement, thereby causing undesirable overhead signaling.

[0041] For dual-polarized beamforming, antenna elements of both polarizations are used to produce a wide beam. The advantage of this approach is that in many cases the desired beam shape can be obtained by phase tapering only, which means that all PAs can be transmitted at full power (or no attenuation is needed in case of a common PA). As the inventors have realized, the disadvantage of dual-polarized beamforming is that only a single beam port can be generated for a panel architecture where only antenna elements of the same polarization are connected to each antenna port. However, the inventors have also realized that this is not a problem for cell-defining reference signals such as SSBs, which have only one port.

[0042] Figure 3 is a flowchart illustrating embodiments of a method for communicating in a wireless access network 100 using a dual-polarized antenna array 170. The antenna array 170 comprises antenna elements 172a, 172b of a first polarization and a second polarization. The method is advantageously performed by an antenna array control unit 200. The methods are advantageously provided as computer programs 720.

[0043] The embodiments disclosed herein are based on using dual-polarized beamforming to create a transmit beam 150a with one single beam port.

[0044] S104: Transmitting a first signal on a first link of the wireless access network 100 via a transmit antenna port in the transmit beam 150a. The transmit antenna port is connected to antenna elements 172a, 172b of both the first polarization and the second polarization.

[0045] The embodiments disclosed herein are based on using single-polarized beamforming to create receive beams with two beam ports, one in each of the two polarizations.

[0046] S108: Receiving a second signal on a second link of the wireless access network 100 via a first receive antenna port in a first receive beam 150b and via a second receive antenna port in a second receive beam 150c. The first receive antenna port is connected to antenna elements 172a of the first polarization and the second receive antenna port is connected to antenna elements 172b of the second polarization. The receive beams 150b, 150c and the transmit beam 150a satisfy an overlap criterion regarding their total power patterns.

[0047] In some examples, at least 75% of the total power of each of the receive beams 150b, 150c is within the same angular interval as at least 75% of the total power of the transmit beam 150a according to the overlap criterion. The angular interval contains the main lobe of each of the receive beams 150b, 150c and the main lobe of the transmit beam 150a.

[0048] In some examples, according to the overlap criterion, a variance of a difference between a gain of each of the receive beams 150b, 150c and a gain of the transmit beam 150a, when calculated in a decibel (dB) scale, is less than 1 dB.

[0049] Thus, by applying single-polarization beamforming on the inherent polarization of the dual-polarized antenna array 170, two receive antenna ports with orthogonal polarizations are created, enabling receive diversity.

[0050] The term "power" as used herein can have two different meanings. On the one hand, the output power from the power amplifier should be as much as possible when generating the transmit beam 150a. On the other hand, for the transmit beam 150a, the power is summed from the two orthogonal polarizations.

[0051] Embodiments related to further details of the communication in the wireless access network 100 using the dual-polarized antenna array 170 will now be disclosed, which embodiments are advantageously performed by the antenna array control unit 200.

[0052] In some examples, the first signal is a first single-port signal and the second signal is a second single-port signal. However, in other examples, the second signal is a dual-port signal (or even an arbitrary port signal).

[0053] Aspects of beamforming will now be disclosed.

[0054] As mentioned above, beamforming can be achieved by applying beamforming weights in the feed network 174. Thus, according to embodiments, step S102 and step S106 are performed.

[0055] S102: The antenna array 170 is configured a first set of beamforming weights for transmitting a first signal. The first set of beamforming weights is adapted to provide a transmit antenna port. The beamforming weights for the antenna elements 172a for a first polarization are different from the beamforming weights for the antenna elements 172b for a second polarization.

[0056] In this regard, the difference between the beamforming weights for the antenna elements 172b for the second polarization and the beamforming weights for the antenna elements 172a for the first polarization is larger than a common phase shift (i.e. a phase shift that is common for all antenna elements 172b).

[0057] S106: The antenna array 170 is configured with a second set of beamforming weights and a third set of beamforming weights for receiving the second signal. The second set of beamforming weights is adapted to provide a first receive antenna port. The third set of beamforming weights is adapted to provide a second receive antenna port. Since the first receive antenna port is connected to the antenna elements 172a of the first polarization and the second receive antenna port is connected to the antenna elements 172b of the second polarization, the second set of beamforming weights only applies to the antenna elements 172a of the first polarization and the third set of beamforming weights only applies to the antenna elements 172b of the second polarization.

[0058] There can be different ways to find the beamforming weights. In some aspects, multi-objective optimization is used to find the beamforming weights. Thus, in some embodiments, any of the first set of beamforming weights, the second set of beamforming weights, or the third set of beamforming weights is determined via multi-objective optimization with at least two costs. In some examples, one of the costs is a maximum amount of main lobe ripples and the other of the costs is a maximum side lobe power level. Other techniques, possibly with other costs, can also be used to find the beamforming weights.

[0059] In some embodiments, the first set of beamforming weights all have equal amplitudes. For example, all can use phase-only tapering, where the first set of beamforming weights all have unit amplitudes.

[0060] Aspects of receiving the second signal will now be disclosed.

[0061] In some aspects, to exploit the receiver diversity, a combination of the received signals is formed. Thus, depending on the embodiment, step S110 is performed.

[0062] S110: The second signal received via the first receive antenna port is combined with the second signal received via the second receive antenna port.

[0063] In some aspects, the combination is based on a relation of a received signal quality on the first receive antenna port and a received signal quality on the second receive antenna port.

[0064] There can be different ways to combine the second signal received via the first receive antenna port with the second signal received via the second receive antenna port. In some embodiments, the combination is maximum ratio combining (MRC). Thus, for the reception, the transceiver 180 can perform polarization matching of the received signals by using, for example, MRC.

[0065] Embodiments will now be disclosed where the antenna array 170 and the antenna array control unit 200 are part of the access node 140. In these embodiments, the first link is a downlink and the second link is an uplink. There can be different first signals transmitted in step S104. In some non-limiting examples, the first signal is any of the following: SSB, msg2 message, contention resolution grant, data message. There can be different second signals received in step S108. In some non-limiting examples, the second signal is any of the following: SSB report, random access (RA) message, msg3 message, contention resolution message, data message.

[0066] Embodiments will now be disclosed where the antenna array 170 and the antenna array control unit 200 are part of the user node 160. In these embodiments, the first link is an uplink and the second link is a downlink. There can be different first signals transmitted in step S104. In some non-limiting examples, the first signal is any of the following: physical uplink control channel (PUCCH) message, single port sounding reference signal (SRS), fixed rank 1 physical uplink shared channel (PUSCH) transmission message. There can be different second signals received in step S108. In some non-limiting examples, the second signal comprises any of the following: physical downlink control channel (PDCCH) transmission, physical downlink shared channel (PDSCH) transmission, channel state information reference signal (CSI-RS) transmission (including tracking reference signal (TRS)), phase tracking reference signal (PTRS) transmission, demodulation reference signal (DMRS) transmission.

[0067] Figure 4 An example is shown comparing the total power pattern of a beam generated using single polarized beamforming (SPBF) with the total power pattern of a beam generated using dual polarized beamforming (DPBF). Figure 4 The total power pattern in azimuth dimension is shown. The beam is designed to cover a certain angular sector. For the beam generated using dual polarized beamforming, only phase tapering is used. The beamforming weights for the beam generated using dual polarized beamforming are found via a multi-objective optimization with two costs; the ripple in the main beam direction and the other is the sidelobe level that exceeds the desired level. By applying a higher cost on the ripple in the optimization, the ripple can be further reduced. To take the impact of amplitude tapering into account, both total power patterns are normalized by directivity to take the total transmit power into account. This means that the difference in power amplifier power (SPBF is 3.6 dB lower than DPBF) is not reflected in the figure. The shape of the main lobe of the beam generated using dual polarized beamforming is similar to the shape of the main lobe of the beam generated using single polarized beamforming. Thus, there is a good match between the beams used for transmission and reception, respectively.Figure 4 The examples in Figs. 1 1 - 13 show that it is possible to use dual-polarized beamforming and single-polarized beamforming to generate beams, where the main lobe has the same shape.

[0068] Figure 5 The components of the antenna array control unit 200 according to an embodiment are schematically shown in the form of a number of functional units. The processing circuitry 210 is provided with any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 710 (as in Fig. 1 1 ) in the form of, e.g., a storage medium 230. Figure 7 The processing circuitry 210 can further be provided as at least one special-purpose computer, e.g., in the form of an application-specific integrated circuit (ASIC) or field-programmable gate array (FPGA).

[0069] In particular, the processing circuitry 210 is configured to cause the antenna array control unit 200 to perform a set of operations or steps as described above. For example, the storage medium 230 can store the set of operations, and the processing circuitry 210 can be configured to retrieve the set of operations from the storage medium 230 to cause the antenna array control unit 200 to perform the set of operations. The set of operations can be provided as a set of executable instructions.

[0070] Hence, the processing circuitry 210 is thereby arranged to perform methods as herein disclosed. The storage medium 230 can further include a persistent storage, e.g., may be any single one or combination of magnetic storage, optical storage, solid state storage or even remotely mounted storage. The antenna array control unit 200 can further include a communication interface 220 configured at least for communication with other entities, functions, nodes and devices, e.g., the dual-polarized antenna array 170. The communication interface 220 can thus include one or more transmitters and receivers comprising analogue and digital components. The processing circuitry 210 controls the general operation of the antenna array control unit 200 e.g., by sending data and control signals to the communication interface 220 and the storage medium 230, by receiving data from the communication interface 220 and reporting, and by retrieving data and instructions from the storage medium 230. Other components, and related functionality, of the antenna array control unit 200 are omitted in order not to obscure the concepts presented herein.

[0071] Figure 6 The components of the antenna array control unit 200 according to an embodiment are schematically shown in the form of a number of functional modules. Figure 6 The antenna array control unit 200 of Fig. 1 1 comprises a number of functional modules: a transmitting module 210b configured to perform step S104 and a receiving module 210d configured to perform step S108. Figure 6The antenna array control unit 200 can also comprise a number of optional functional modules, such as a configuration module 210a configured to perform step S102, a configuration module 210c configured to perform step S106, and a combining module 210e configured to perform step S110. In general, each functional module 210a: 210e can in one embodiment be implemented in hardware only, and in another embodiment by means of software, i.e. the latter embodiment has computer program instructions stored on the storage medium 230, which when run on the processing circuitry, causes the antenna array control unit 200 to perform the above mentioned steps in association with the corresponding steps mentioned above. It should also be mentioned that even if the modules correspond to parts of a computer program, they need not be separate modules therein, but they depend on the programming language used in the implementation in software. Preferably, one or more or all functional modules 210a: 210e can be implemented by the processing circuitry 210, possibly in cooperation with the communication interface 220 and / or the storage medium 230. Thus, the processing circuitry 210 can be configured to fetch instructions provided by the functional modules 210a: 210e from the storage medium 230, and to execute these instructions, thereby performing any of the steps as disclosed herein. Figure 6 It should also be mentioned that even if the modules correspond to parts of a computer program, they need not be separate modules therein, but they depend on the programming language used in the implementation in software. Preferably, one or more or all functional modules 210a: 210e can be implemented by the processing circuitry 210, possibly in cooperation with the communication interface 220 and / or the storage medium 230. Thus, the processing circuitry 210 can be configured to fetch instructions provided by the functional modules 210a: 210e from the storage medium 230, and to execute these instructions, thereby performing any of the steps as disclosed herein.

[0072] The antenna array control unit 200 can be provided as a standalone device or as part of at least one further device. For example, the antenna array control unit 200 can be provided in the (radio) access node 140 or in the user node 160. Alternatively, the functionality of the antenna array control unit 200 can be distributed between at least two devices or nodes. A first part of the instructions executed by the antenna array control unit 200 can be executed in a first device, and a second part of the instructions executed by the antenna array control unit 200 can be executed in a second device; the embodiments disclosed herein are not limited to any particular number of devices on which the instructions executed by the antenna array control unit 200 can be executed. Thus, the methods according to the embodiments disclosed herein are suitable for execution by the antenna array control unit 200 residing in a cloud computing environment. Thus, although shown in Figure 5 a single processing circuitry 210, the processing circuitry 210 can be distributed in a plurality of devices or nodes. The same applies to the functional modules 210a: 210c and the computer program 720 of the antenna array control unit 200. Figure 6 the functional modules 210a: 210c and the computer program 720 of the antenna array control unit 200. Figure 7 the functional modules 210a: 210c and the computer program 720 of the antenna array control unit 200.

[0073] Figure 7One example of a computer program product 710 comprising a computer- readable storage medium 730 is shown. In this computer-readable storage medium 730, a computer program 720 can be stored, which computer program 720 can cause the processing circuitry 210 and thus also the apparatus, e.g., the communication interface 220 and the storage medium 230, operably coupled to the processing circuitry 210, to execute methods according to embodiments described herein. The computer program 720 and / or computer program product 710 can thus provide means for performing any of the steps according to any of the embodiments disclosed herein.

[0074] In Figure 7 Examples of computer program product 710 are shown in the examples of FIG. 7 and FIG. 8. In the example of FIG. 7, the computer program product 710 is shown as an optical disc, such as a CD (compact disc) or a DVD (digital versatile disc) or a Blu-Ray disc. The computer program product 710 can also be embodied as a memory, such as a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or an electrically erasable programmable read-only memory (EEPROM) and more particularly as a non-volatile storage medium of a device in an external memory, such as a USB (Universal Serial Bus) memory or a Flash memory, for example a compact Flash. Therefore, although the computer program 720 is here schematically shown as a track on the depicted optical disk, the computer program 720 can be stored in any way which is appropriate for the computer program product 710.

[0075] Figure 8 is a schematic diagram illustrating a telecommunication network connected via an intermediate network 420 to a host computer 430, in accordance with some embodiments. The communication system includes a telecommunication network 410, such as a 3GPP-type cellular network, which comprises Figure 1 an access network 411 of (radio) access network 110 in Figure 1 and a core network 414, such as core network 120 in Figure 1The radio access network 410 can interface with a core network 414, which can provide user authentication, access administration, and mobility management for the UEs 491, 492 that enter a coverage area of the radio access network 410. There can be multiple cells (not shown) within the radio access network 410, each cell being serviced by a corresponding network node 412a, 412b, 412c, which can be a base station, or network access node, or network node, or radio access node, or transmission and reception point (TRP) in the access network 410. The network nodes 412a, 412b, 412c can be base stations, which can be referred to as NodeBs, NodeBbs, evolved NodeBs, gNBs, RAN nodes, RBSs, or RAN nodes 412a, 412b, 412c in 5G systems. The network nodes 412a, 412b, 412c can be connected to the core network 414 via the wired or wireless connection 415. A first UE 491 located in coverage area 413c is configured to wirelessly connect to, or be paged by, the corresponding network node 412c. A second UE 492 in coverage area 413a is wirelessly connectable to the corresponding network node 412a. While a plurality of UEs 491, 492 are illustrated in this example, the disclosed embodiments equally apply to a situation where only a single UE is in the coverage area or where only a single terminal device is connecting to the corresponding network node 412. The UEs 491, 492 correspond to the user nodes 160 of Fig. 1. Figure 1

[0076] The telecommunication network 410 is itself connected to a host computer 430, which can be implemented as a hardware and / or software in a standalone server, a cloud-implemented server, a distributed server, or as a processing resource in a server farm. The host computer 430 can be under the ownership or control of a service provider, or can be operated by the service provider or on behalf of the service provider. The connections 421 and 422 between the telecommunication network 410 and the host computer 430 can extend directly from the core network 414 to the host computer 430 or can go via an optional intermediate network 420. The intermediate network 420 can be one of a public, private, or hosted network; the intermediate network 420 can be a combination of two or more networks; the intermediate network 420 can include the Internet; and the connections 421 and 422 can be

[0077] Figure 8 ​The communication system as a whole enables connectivity between the connected UEs 491, 492 and the host computer 430. The connectivity can be described as an over-the-top (OTT) connection 450. The host computer 430 and the connected UEs 491, 492 are configured to communicate data and / or signaling via the OTT connection 450 using the access network 411, the core network 414, any intermediate network 420 and possible further infrastructure (not shown) as intermediaries. The OTT connection 450 can be transparent in the sense that the participating communication devices (e.g., the network nodes 412) do not, or need not, understand the data and / or signaling passing therethrough. For example, the network nodes 412 can not be aware of the fact that the incoming data and / or signaling is part of a session between the host computer 430 and the UE 491, or between the host computer 430 and the UE 492. The OTT connection 450 can be configured to carry data and / or signaling between the host computer 430 and the UE 491, 492 using an uplink (UL) and a downlink (DL) communication channel. The UL and DL communication channels can be used together simultaneously or at different times. In the former case, the OTT connection 450 can be configured to carry the data and / or signaling bi-directionally between the host computer 430 and the UE 491, 492. In the latter case, the OTT connection 450 can be configured to carry the data and / or signaling unidirectionally between the host computer 430 and the UE 491, 492 at a time. The OTT connection 450 can be implemented as a packet- switched connection. The OTT connection 450 can be configured to use a wireless access radio

[0078] Figure 9 is a schematic diagram illustrating a host computer communicating via a radio access network node with a UE over a partially wireless connection according to some embodiments. Example implementations of the UE, the radio access network node and the host computer discussed in the preceding paragraph will now be described with reference to Figure 9 In the communication system 500, a host computer 510 is configured to communicate via a radio access network 411 with a UE 530 using an OTT connection 550. The host computer 510 can be implemented as any kind of computing device or any kind of user equipment, e.g. as a server computer, a personal computer, a laptop computer, a notebook computer, a tablet computer, a personal digital assistant, or a mobile phone. The UE 530 can be implemented as any kind of user equipment, e.g. as a server computer, a personal computer, a laptop computer, a notebook computer, a tablet computer, a personal digital assistant, or a mobile phone. The UE 530 is configured to communicate with the radio access network 411 via a wireless access interface 551. The radio access network 411 is configured to communicate with the UE 530 via the wireless access interface 551. The radio access network 411 can be implemented as any kind of network node or base station, e.g. as a server computer, a personal computer, a laptop computer, a notebook computer, a tablet computer, a personal digital assistant, or a mobile phone. The host computer 510 and the UE 530 are configured to communicate with each other via the OTT connection 550 using the radio access network 411 as an intermediary. The host computer 510 is configured to transmit data to the UE 530, and to receive data from the UE 530, using the OTT connection 550. The data transmitted by the host computer 510 to the UE 530 can include data to be Figure 1

[0079] ​The communication system 500 also includes a radio access network node 520 provided in the telecommunications system. The radio access network node 520 includes hardware 525 enabling it to communicate with the host computer 510 and the UE 530. The radio access network node 520 corresponds to... Figure 1 The (radio) access node 140. Hardware 525 may include: a communication interface 526 for establishing and maintaining wired or wireless connections with interfaces of different communication devices of the communication system 500; and a radio interface 527 for establishing and maintaining connections with at least the coverage area served by the radio access network node 520. Figure 9 The UE 530 (not shown in the image) has a wireless connection 570. The communication interface 526 can be configured to facilitate a connection 560 to the host computer 510. The connection 560 can be direct, or it can be via the core network of the telecommunications system (…). Figure 9 (Not shown) and / or via one or more intermediate networks outside the telecommunications system. In the illustrated embodiment, the hardware 525 of the radio access network node 520 also includes processing circuitry 528, which may include one or more programmable processors, application-specific integrated circuits, field-programmable gate arrays, or combinations thereof (not shown) suitable for executing instructions. The radio access network node 520 also has internally stored software 521 or accessible via an external connection.

[0080] The communication system 500 also includes the previously mentioned UE 530. Its hardware 535 may include a radio interface 537 configured to establish and maintain wireless connections 570 with radio access network nodes serving the coverage area currently occupied by the UE 530. The hardware 535 of the UE 530 also includes processing circuitry 538, which may include one or more programmable processors, application-specific integrated circuits, field-programmable gate arrays, or combinations thereof (not shown) suitable for executing instructions. The UE 530 also includes software 531, which is stored in or accessible by the UE 530 and executable by the processing circuitry 538. The software 531 includes a client application 532. The client application 532 is operable to provide services to human or non-human users via the UE 530 with the support of a host computer 510. In the host computer 510, a host application 512 executing may communicate with the client application 532 via an OTT connection 550 terminated at the UE 530 and the host computer 510. When providing services to a user, client application 532 can receive request data from host application 512 and provide user data in response to the request data. OTT connection 550 can transmit both request data and user data. Client application 532 can interact with the user to generate the user data it provides.

[0081] Notice,Figure 9 The host computer 510, the radio access network node 520, and the UE 530 illustrated can be similar or identical to the host computer 430, one of the network nodes 412a, 412b, 412c, and one of the UEs 491, 492 of Figure 8 Figure 4, respectively. That is, the inner workings of these entities can be as illustrated in Figure 9 and independently, the surrounding network topology can be Figure 8 the network topology of Figure 4.

[0082] In the example of Figure 5, the OTT connection 550 has been drawn as a dashed line to indicate that it is not a physical connection, but rather a virtual connection that transmits data between the host computer 510 and the UE 530. In Figure 9 the abstract, the OTT connection 550 is drawn from the host computer 510 to the UE 530 via the radio access network node 520 to indicate that the host computer 510 is in communication with the UE 530 via the radio access network node 520, without

[0083] the precise routing of messages via the network infrastructure. The network infrastructure can determine the routing of messages, which can be configured to hide from the host computer 510 or from the service provider operating the host computer 510, or both. While the OTT connection 550 is active, the network infrastructure can further take decisions on whether to change the routing e.g. based on load balancing consideration or reconfiguration of the network.

[0084] A measurement procedure can be implemented for the purpose of monitoring the data rate, latency and other factors that can influence the behaviour of one or more embodiments. There can further be an optional network functionality for reconfiguring the OTT connection 550 between the host computer 510 and the UE 530, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection 550 can be implemented in the software 511 and the hardware 515 of the host computer 510 or in the software 531 and the hardware 535 of the UE 530, or both. In embodiments, sensors (not shown) can be deployed in or in association with communication devices through which the OTT connection 550 passes; the sensors can participate in the measurement procedure by supplying values of the above-illustrated example monitored quantities, or values of other physical quantities from which software 511, 531 can compute or estimate the monitored quantities. The reconfiguring of the OTT connection 550 can include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not affect the radio access network 520, and it can be unknown or imperceptible to the radio access network 520. Such procedures and functionalities can be known and practiced in the art. In certain embodiments, the measurements can involve proprietary UE signaling facilitating the host computer's 510 measurements of throughput, propagation times, latency and the like. The measurements can be realized as software loops that the software 511, 531 enables to use the OTT connection 550 for transmitting messages (specifically, empty messages, or "dummy" messages), while the software 511, 531 monitors propagation times, errors etc.

[0085] The inventive concept has primarily been described above with reference to some embodiments. However, a person of ordinary skill in the art could make various modifications to the embodiments disclosed herein without departing from the scope of the inventive concept, which is defined by the appended patent claims.

Claims

1. A method for communicating in a wireless access network (100) using a dual polarized antenna array (170), the antenna array (170) comprising antenna elements (172a, 172b) of a first polarization and a second polarization, the method comprising: transmitting (S104) a first signal on a first link of the wireless access network (100) via a transmit antenna port in a transmit beam (150a), wherein the transmit antenna port is connected to antenna elements (172a, 172b) of both the first polarization and the second polarization; receiving (S108) a second signal on a second link of the wireless access network (100) via a first receive antenna port in a first receive beam (150b) and via a second receive antenna port in a second receive beam (150c); and combining (S110) the second signal received via the first receive antenna port in the first receive beam (150b) with the second signal received via the second receive antenna port in the second receive beam (150c), wherein the first receive antenna port is connected to antenna elements (172a) of the first polarization and the second receive antenna port is connected to antenna elements (172b) of the second polarization, and wherein the receive beams (150b, 150c) and the transmit beam (150a) satisfy an overlap criterion with respect to a total power pattern of the receive beams (150b, 150c) and the transmit beam (150a).

2. The method according to claim 1, further comprising: configuring (S102) a first set of beamforming weights for the antenna array (170) for transmitting the first signal, wherein the first set of beamforming weights is adapted to provide the transmit antenna port, and wherein beamforming weights for antenna elements (172a) of the first polarization are different from beamforming weights for antenna elements (172b) of the second polarization; and configuring (S106) a second set of beamforming weights and a third set of beamforming weights for the antenna array (170) for receiving the second signal, wherein the second set of beamforming weights is adapted to provide the first receive antenna port, and wherein the third set of beamforming weights is adapted to provide the second receive antenna port.

3. The method of claim 2, wherein, Any one of the first, second or third set of beamforming weights is determined via a multi-objective optimization with at least two costs.

4. The method of claim 3, wherein, One of the costs is a maximum amount of main lobe ripples and another one of the costs is a maximum side lobe power level.

5. The method of claim 2, wherein, The first set of beamforming weights all have equal amplitudes.

6. The method of claim 1, wherein, The combining is based on a relation of a received signal quality on the first receive antenna port and a received signal quality on the second receive antenna port.

7. The method of claim 1, wherein, The combining is maximum ratio combining.

8. The method of claim 1, wherein, The antenna power pattern is a wide beam pattern spanning an angular interval between 10 degrees and 40 degrees.

9. The method of claim 1, wherein, The antenna power pattern is a wide beam pattern spanning an angular interval between 15 and 30 degrees.

10. The method of claim 1, wherein, The first signal is a first single-port signal and the second signal is a second single-port signal.

11. The method of any one of claims 1 to 10, wherein, The method is performed by an antenna array control unit (200).

12. The method of claim 11, wherein, The antenna array (170) and the antenna array control unit (200) are part of an access node (140).

13. The method of claim 12, wherein, The first link is a downlink and the second link is an uplink.

14. The method of claim 13, wherein, The first signal comprises any of: an SSB, a msg2 message, a contention resolution grant, a data message.

15. The method of claim 13, wherein, The second signal comprises any of: an SSB report, a RA message, a msg3 message, a contention resolution message, a data message.

16. The method of claim 11, wherein, The antenna array (170) and the antenna array control unit (200) are part of a user node (160).

17. The method of claim 16, wherein, The first link is an uplink and the second link is a downlink.

18. The method of claim 17, wherein, The first signal is any of: a PUCCH message, a single-port SRS, a fixed rank 1 PUSCH transmission message.

19. The method of claim 17, wherein, The second signal is any of: a PDCCH transmission, a PDSCH transmission, a CSI-RS transmission, a PTRS transmission, a DMRS transmission.

20. An antenna array control unit (200) for communicating in a wireless access network (100) using a dual-polarized antenna array (170), the antenna array (170) comprising antenna elements (172a, 172b) of a first polarization and a second polarization, the antenna array control unit (200) comprising processing circuitry (210), the processing circuitry being configured to cause the antenna array control unit (200) to: transmitting a first signal via a transmit antenna port in a transmit beam (150a) on a first link of the wireless access network (100), wherein connect a transmit antenna port to antenna elements (172a, 172b) of both the first polarization and the second polarization; receive a second signal on a second link of the wireless access network (100) via a first receive antenna port in a first receive beam (150b) and via a second receive antenna port in a second receive beam (150c); and combine the second signal received via the first receive antenna port in the first receive beam (150b) with the second signal received via the second receive antenna port in the second receive beam (150c), wherein the first receive antenna port is connected to antenna elements (172a) of the first polarization and the second receive antenna port is connected to antenna elements (172b) of the second polarization, and wherein the receive beams (150b, 150c) and the transmit beam (150a) satisfy an overlap criterion with respect to a total power pattern of the receive beams (150b, 150c) and the transmit beam (150a).

21. The antenna array control unit (200) of claim 20, further configured to perform the method of any of claims 2 to 19.

22. An antenna array control unit (200) for communicating in a radio access network (100) using a dual polarized antenna array (170), the antenna array (170) comprising antenna elements (172a, 172b) of a first polarization and a second polarization, the antenna array control unit (200) comprising: a transmitting module (210b) configured to transmit a first signal on a first link of the radio access network (100) via a transmitting antenna port in a transmitting beam (150a), wherein the transmitting antenna port is connected to antenna elements (172a, 172b) of both the first polarization and the second polarization; a receiving module (210d) configured to receive a second signal on a second link of the radio access network (100) via a first receiving antenna port in a first receiving beam (150b) and via a second receiving antenna port in a second receiving beam (150c); and a combining module (210e) configured to combine the second signal received via the first receiving antenna port in the first receiving beam (150b) with the second signal received via the second receiving antenna port in the second receiving beam (150c), wherein the first receiving antenna port is connected to antenna elements (172a) of the first polarization and the second receiving antenna port is connected to antenna elements (172b) of the second polarization, and wherein the receiving beams (150b, 150c) and the transmitting beam (150a) satisfy an overlap criterion with respect to a total power pattern of the receiving beams (150b, 150c) and the transmitting beam (150a).

23. The antenna array control unit (200) according to claim 22, further configured to perform the method according to any one of claims 2 to 19.

24. A computer-readable storage medium (730) having stored thereon a computer program (720) for communicating in a radio access network (100) using a dual polarized antenna array (170), the antenna array (170) comprising antenna elements (172a, 172b) of a first polarization and a second polarization, the computer program comprising computer code which, when run on processing circuitry (210) of an antenna array control unit (200), causes the antenna array control unit (200) to: transmitting (S104) a first signal on a first link of the wireless access network (100) via a transmit antenna port in a transmit beam (150a), wherein the transmitting antenna port is connected to antenna elements (172a, 172b) of both the first polarization and the second polarization; receive (S108) a second signal on a second link of the radio access network (100) via a first receiving antenna port in a first receiving beam (150b) and via a second receiving antenna port in a second receiving beam (150c); and combine (S110) the second signal received via the first receiving antenna port in the first receiving beam (150b) with the second signal received via the second receiving antenna port in the second receiving beam (150c), wherein the first receive antenna port is connected to the antenna element of the first polarization (172a) and the second receive antenna port is connected to the antenna element of the second polarization (172b), and wherein the receive beams (150b, 150c) and the transmit beam (150a) satisfy an overlap criterion with respect to a total power pattern of the receive beams (150b, 150c) and the transmit beam (150a).

25. A computer program product (710) comprising the computer readable storage medium (730) of claim 24.

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