Circular beams as replacements of massive MIMO beams

Abstract

An embodiment may include an example method, which may involve scheduling circular beam's downlink and uplink in-phase and quadrature (I / Q) signals, converting massive MIMO beam I / Q signals without actually performing beamforming, maintaining a beams-to-radio-heads mapping where the mapping is either statically configured during installation or dynamically updated using various algorithms, routing a beam's digital downlink signals to radio heads or broadcasting all beams' digital downlink signals to radio heads, digitally summing the digital uplink signals belonging to the same beam, A / D and D / A converting, and transmitting or receiving via antennas to form circular beams.

Description

Attorney Docket No. 25-0009-WOCircular Beams as Replacements of Massive MIMO BeamsCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. provisional patent application no.63 / 742,173, filed January 6, 2025, which is hereby incorporated by reference in its entirety.BACKGROUND

[0002] Massive multiple-input and multiple-output (MIMO) and beamforming are features in 5G cellular wireless network technologies to improve coverage and increase the throughput of a 5G base station, such as a gNodeB (gNB). However these features require extensive computational power and large antennas, and thus may not be suitable for use inside buildings and in tunnels. 5G small cells (low-powered base stations with limited coverage) may be better suited for inside building and tunnels, however cell overlap and frequent handover can severely reduce effective coverage and throughput.SUMMARY

[0003] Compared to earlier wireless radio network systems, 5G technologies use increased bandwidth to offer fast downlink and uplink speeds to user equipment (UEs). Low frequency wireless bands have been previously allocated for 4G, 3G, or even 2G technologies, and as a consequence, these technologies are subject to limited bandwidth. 5G technology typically operates on higher frequency bands. Use of these high frequency bands introduces fast fading when radio frequency (RF) signals are transmitted over an air interface and thus general produce high-throughput but smaller wireless coverage areas in which UEs can communicate with 5G gNBs.

[0004] Massive MIMO and beamforming use signal processing techniques. Particularly, signals transmitted from an antenna array of a gNB constructively interfere with one other to form narrow directional radio signals that are beamed toward targeted UEs. Different beams appear in different geographical areas so they do not interfere with each other. Thus, the same frequency can be reused from beam to beam, significantly increasing frequency efficiency and supporting high throughput.

[0005] 3GPP specifications have defined 5G communication protocols that both a gNB and a UE follow. The UE detects beams with corresponding beam identifiers (IDs) from synchronization signal block (SSB) transmissions when idle or its assigned channel signalwhile connected. The UE reports it’ s measured beam IDs and signal qualities via random access procedures when idle or via channel signal indication (CSI) when connected.

[0006] Beamforming requires a gNB to be equipped with an antenna array and significant computational power. But a beam formed to cover a small area does not have to be a narrow beam. A circular beam that is spatially distributed over an area could be another implementation of beamforming. The UE does not know that the received beam signals are coming from narrow beams or from circular beams. As long as UE receives a beam ID, it can measure each beam’s channel signals and provide feedback to the transmitting gNB.

[0007] In other words, a radio head and a circular beam can be used to present UEs with beams. A radio head and a circular beam can perform radio signal spreading without the computational and electronic circuit complexity of existing techniques. Such a gNB normally only needs to support 2x2 MIMO (with two transmitters and two receivers) or 4x4 MIMO (with four transmitters and four receivers) rather than 16x16 MIMO (with sixteen transmitters and sixteen receivers). The size and weight of these smaller MIMO antenna arrays are less than for massive MIMO antennas.

[0008] In some deployment scenarios, massive MIMO beamforming is not suitable. For example, in a tunnel deployment, UEs are distributed in one dimension. Massive MIMO beamforming cannot target a particular UE as the beam will pass through other UEs connected to the gNB. Also, in an in-building deployment such as a manufacturing facility or an office building, a narrow beam can be easily blocked and / or attenuated by a machine or a wall.

[0009] The radio head of a gNB (which is responsible for wireless signal transmission and reception, encompassing antennas and RF components) configured with circular beam technology addresses these deployment challenges. A circular beam can be distributed linearly along a tunnel or strategically placed to cover a small area inside a building. One radio head’s circular beam will not interfere with other radio heads’ circular beams. Therefore, frequencies of these beams can be reused. In these deployments, circular beams achieve the same advantages introduced by the traditional narrow beams.

[0010] Circular beams also fit the O-RAN architecture. In this architecture, the gNB includes an O-RAN RU, along with a distribution unit (DU) configured for handling baseband signal processing, protocol termination, data forwarding, and synchronization, and a central unit (CU) configured for managing network functions, resource allocation, traffic management, and connection establishment. An O-RAN RU may use predefined beamforming methods, and reports the information including number of beams to the O-RAN DU. The O-RAN DU sends in-phase and quadrature (I / Q) data for each beam using a predefined protocol, such as thestandard enhanced common public radio interface (eCPRI) protocol. The O-RAN RU maintains a beams-to-radio heads mapping, either statically or dynamically, with each beam corresponding to one or more radio heads (here, a radio head may include transmitters, receivers, power amplifiers, filters, and / or digital processing units). Instead of phase-shifting signals and feeding to massive MEMO antenna, the O-RAN RU may simply convert I / Q data to digital downlink signals and use the beam ID to route the signals to the corresponding radio heads.

[0011] In-phase and quadrature (I / Q) data represents a complex- valued digital representation of an RF signal, consisting of two separate components that are 90 degrees out of phase with one another. In the context of the present disclosure, the in-phase (I) component typically corresponds to a cosine carrier, while the quadrature (Q) component typically corresponds to a sine carrier, forming an orthogonal basis that fully describes the amplitude, phase, and frequency of the modulated waveform. Within the O-RAN architecture, the DU generates and provides these I / Q signals in the frequency domain for each circular radio frequency beam. These signals are then transmitted to an AU via a predefined protocol, such as eCPRI.

[0012] Accordingly, a first example embodiment may involve a gNB comprising a base band unit (BBU) and multiple remote radio units (RRUs), where the BBU schedules massive MIMO without beamforming and the RRUs transmit digital downlink signals to form one or more circular beams. One general aspect involves a method. The method includes retrieving, by a distribution unit of a radio network, predefined beam information for one or more circular radio frequency beams. The method also includes providing, by the distribution unit, in-phase and quadrature frequency domain signals of the one or more circular radio frequency beams to an access unit of the radio network. The method also includes using, by the access unit, beam identifiers for each of the circular radio frequency beams to route digital downlink signals to one or more radio heads, where the digital downlink signals are based on the in-phase and quadrature frequency domain signals. The method also includes converting, by the one or more radio heads, the digital downlink signals into analog downlink signals. The method also includes providing, by the one or more radio heads, the analog downlink signals to antenna ports.

[0013] A second example embodiment may involve an O-RAN RU receiving each beam’s I / Q signals from an O-RAN DU and distributing time domain digital RF signals to radio heads forming circular beams. One general aspect involves a method. The method includes receiving, by one or more radio heads and by way of one or more antennas, uplinkanalog signals by way of circular radio frequency beams. The method also includes converting, by the one or more radio heads, the uplink analog signals into digital uplink signals. The method also includes providing, by the one or more radio heads, the digital uplink signals to an access unit of a radio network. The method also includes summing, by the access unit, the digital uplink signals from different ones of the radio heads corresponding to common circular radio frequency beams. The method also includes converting, by the access unit and for each of the common circular radio frequency beams, the digital uplink signals from a time domain to a frequency domain. The method also includes providing, by the access unit, frequency domain information for each of the common circular radio frequency beams to a distribution unit of the radio network.

[0014] Other embodiments include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices (e.g., on non-transitory computer-readable media), each configured to perform the actions of the methods.

[0015] These, as well as other embodiments, aspects, advantages, and alternatives, will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying drawings. Further, this summary and other descriptions and figures provided herein are intended to illustrate embodiments by way of example only and, as such, that numerous variations are possible. For instance, structural elements and process steps can be rearranged, combined, distributed, eliminated, or otherwise changed, while remaining within the scope of the embodiments as claimed.BRIEF DESCRIPTION OF THE FIGURES

[0016] Figure 1 depicts massive MEMO beamforming, in accordance with example embodiments.

[0017] Figure 2 depicts circular beams distributed along a tunnel, in accordance with example embodiments.

[0018] Figure 3 depicts circular beams distributed in a building, in accordance with example embodiments.

[0019] Figure 4 depicts a gNB BBU and RRU implementing circular beams, in accordance with example embodiments.

[0020] Figure 5 depicts a distributed antenna system (DAS) system as an O-RAN RU, in accordance with example embodiments.

[0021] Figure 6 depicts computing devices for a DAS AU and a DAS radio head, in accordance with example embodiments.

[0022] Figure 7 depicts a flow chart, in accordance with example embodiments.

[0023] Figure 8 depicts a flow chart, in accordance with example embodiments.

[0024] Figure 9 depicts a flow chart, in accordance with example embodiments.DETAILED DESCRIPTION

[0025] Example methods, devices, and systems are described herein. It should be understood that the words “example” and “exemplary” are used herein to mean “serving as an example, instance, or illustration.” Any embodiment or feature described herein as being an “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or features unless stated as such. Thus, other embodiments can be utilized and other changes can be made without departing from the scope of the subject matter presented herein.

[0026] Accordingly, the example embodiments described herein are not meant to be limiting. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations. For example, the separation of 0-RAN RU into DAS AU and DAS RUs may occur in a number of ways.

[0027] Further, unless context suggests otherwise, the features illustrated in each of the figures may be used in combination with one another. Thus, the figures should be generally viewed as component aspects of one or more overall embodiments, with the understanding that not all illustrated features are necessary for each embodiment.

[0028] Additionally, any enumeration of elements, blocks, or steps in this specification or the claims is for purposes of clarity. Thus, such enumeration should not be interpreted to require or imply that these elements, blocks, or steps adhere to a particular arrangement or are carried out in a particular order.

[0029] Unless clearly indicated otherwise herein, the term “or” is to be interpreted as the inclusive disjunction. For example, the phrase “A, B, or C” is true if any one or more of the arguments A, B, C are true, and is only false if all of A, B, and C are false.I. Overview

[0030] As noted above, massive MEMO beamforming requires many antennas (e.g., by way of an antenna array) and computational power to shift signals in phases before feeding these signals to different antennas. These antennas radiate to define RF signals that constructively interfere with one other resulting in a narrow beam. Figure 1 uses 0-RAN architecture to illustrate a beamforming system 100. Blocks 101, 102, and 103 are 0-RAN CU, DU, and RU components, respectively. Block 104 is an Fl interface and protocol between CU 101 and DU 102. Block 105 is an eCPRI interface and protocol between DU 102 and RU 103. RU 103 has an antenna array 106 including of four antenna elements 107. Each antenna element has four 2x2 (X and Y polarized) antennas, in total a 16x16 antenna array forming 8 beams 108(only 5 are shown for convenience). When antennas are required to support high output power, say 40W, the antenna array will be huge in weight and in size. Computational power requirements for constantly shifting 16 antenna signals is extremely high.

[0031] Figure 2 illustrates a deployment scenario example 200 in a tunnel 201 where four circular beams 202 are distributed to cover the majority or whole of tunnel 201. Figure 3 illustrates yet another deployment scenario example 300 in a three floor building 301. Figure 3 illustrates that ten circular beams 302 can be spatially placed to cover the whole building 301.II. Example Circular Beam Systems

[0032] The following description and accompanying drawings will elucidate features of various example embodiments. The embodiments provided are by way of example, and are not intended to be limiting. As such, the dimensions of the drawings are not necessarily to scale.A. Example Circular Beam System Using BBU and RRU

[0033] Figure 4 illustrates an overview of an example circular beam system 400 using the BBU and RRU architecture. Traditional base stations are implemented in the BBU and RRU architecture where BBU implements all base station functions in the digital domain and the RRU converts between digital signals and analog signals. The RRU may also amplify signals to and from antennas.

[0034] A circular beam system includes one BBU and multiple RRUs. Block 401 is the BBU. Instead of beamforming, BBU 401 converts a beam signal into an RF signal, ignoring phase-shifting and a weight vector normally associated with a beam. BBU 401 maintains a beams-to-RRUs mapping. This mapping may be statically defined during installation. The mapping could also be dynamically updated based on time of day or day of a week. The mapping may be further adjusted using any intelligent algorithm such as the beams’ traffic load or other factors. Block 402 is the RRU. It converts digital RF signals to and from analog signals. It may amplify signals to and from antennas. Normally BBU 401 feeds signals of a sector to one RRU 402. In this example system, BBU 401 feeds signals of a beam to one or multiple RRUs 402 based on the beams-to-RRUs mapping.B. Example Circular Beam System Using O-RAN Architecture

[0035] Figure 5 illustrates an overview of another example circular beam system using the O-RAN architecture. The circular beam system 500 may include an O-RAN CU 501 and an O-RAN DU 502 connected via a fiber interface and Fl protocol 503, and an enhanced O-RAN RU 504 connected to O-RAN DU 502 via a fiber interface and eCPRI protocol 505. TheO-RAN RU 504 may consist of an access unit (AU) 506 and multiple radio heads 507 creating circular beams 508.

[0036] O-RAN RU 504 may use a predefined beam creation method and report beam information to O-RAN DU 502. O-RAN DU 502 schedules downlink and uplink transmissions to and from each O-RAN RU 504 for each beam’s I / Q signal via eCPRI 505 ’s control and user planes. AU 506 may maintain a beams-to-radio-heads mapping. The mapping may be statically configured during installation or dynamically adjusted using time of a day or day of a week. The mapping may be adjusted using any intelligent algorithm. AU 506 may convert I / Q signals to digital RF signals (e.g., represented by the eCPRI protocol) by ignoring beamforming. It may route digital RF signals to and from radio head 507 using the maintained mapping. Alternatively, AU 506 may broadcast all beam’s digital RF signals to all radio heads 507 and each radio head 507 filters its own beam’s digital RF signal based on its assigned beam ID.C. Example Computing Devices

[0037] Figure 6 is a simplified block diagram exemplifying computing devices for the circular beam system 500, illustrating some of the components that could be included in computing devices arranged to operate in accordance with the embodiments herein. Block 601 is a simplified diagram for the AU. CPU 602 and memory 603 may be configured for processing O-RAN RU functions and conducting eCPRI interfaces. Flash storage 604 stores AU program code and AU configurations including predefined beam information and the beams-to-radio-heads mapping. Digital signal processor (DSP) or field programmable gate array (FPGA) 605 may be an accelerator to help CPU 602 perform computational intensive tasks such as fast Fourier transforms (FFTs) and inverse FFTs. AU 601 eliminates the phase shifting and beamforming function so performance requirements for CPU 602 and FPGA / DSP 605 are reduced. Small form-factor pluggable (SFP) driver 606 and SFP interface card 607 form a fiber interface to communicate with an O-RAN DU (e.g., via the eCPRI protocol). SFP driver 608 and SFP interface card 609 form a fiber interface to communicate with a radio head (e.g., via the eCPRI protocol). SFP driver 608 and SFP interface card 609 may be repeated for every radio head.

[0038] Block 610 is a simplified diagram for a radio head (RH). CPU 611 and memory 612 for a CPU may be configured for processing RH functions and conducting communication interfaces with an AU. Flash storage 613 stores RH code and RH configurations including assigned beam ID information. FPGA / DSP 614 may be used to perform digital pre-distortion if the bi-directional amplifier (BDA) output is high. AD / DA 617 converters converts signal between digital and analog. BDA 618 may amplify downlink signals and uplink signals.Antenna (ANT) 619 may be a physical antenna port connecting to external antennas or internal antennas inside RH 610.III. Example Processes

[0039] Figure 7 illustrates an example process 700 implementing circular beams in an 0-RAN RU using the 0-RAN architecture. Process 700 interworks with any 0-RAN DU that supports massive MIMO beamforming features. The process may operate on or in connection with a DAS system, such as the DAS system 504 illustrated in Figure 5. Process 700 may also operate on AU 601 and RH 610 illustrated in Figure 6.

[0040] Block 701 may involve defining a number of statically beams. The AU also internally maintains a beams-to-radio-heads mapping. This mapping can be statically configured during installation or dynamically changed based on time or any other intelligent algorithm. For example, a beam may only have one RH or a beam may have multiple RH.

[0041] Block 702 may involve using an O-RAN DU to retrieve or otherwise discover the predefined beam information from the O-RAN RU using an M plane protocol as defined in O-RAN architecture. After the O-RAN DU discovers the beam information, the O-RAN DU may schedule and transmit or receive each beam’s I / Q signals. Blocks 703-706 are for downlink transmission and blocks 707-710 are for uplink transmissions.

[0042] Block 703 may use a physical SFP module for the O-RAN DU to send, to the O-RAN RU, the frequency domain I / Q signals for each beam via eCPRI control and user planes as defined in O-RAN specifications.

[0043] In contrast to massive MIMO beamforming, block 704 may simply use iFFT to convert frequency domain I / Q signals to time domain RF digital signals. There is no phase shifting and beamforming calculation required, thereby reducing the computational requirements of the overall system.

[0044] Block 705 may use the beams-to-radio-heads mapping to route RF signals to radio heads via SFP modules and fiber interfaces. Alternatively block 705 may route all beams’ RF signals to some or all radio heads. Each radio head may use its pre-assigned beam ID to pick its corresponding RF signal.

[0045] Block 706 may use D / A converters to convert digital signals into analog signals. This may involve using a bi-directional amplifier to increase the power level before feeding the analog signals to an antenna. Blocks 703-706 are repeated for each antenna port. Block 706 may map each antenna port to a physical antenna.

[0046] Blocks 707-710 are for uplink signal processing. Block 710 may receive uplink signals from an antenna port. A bi-directional amplifier may filter out any out-of-band signalsand amplify the in-band signals. The A / D converter may convert analog signals to time domain digital signals. Some or all of the radio head’s digital signals may be sent to an AU via an SFP fiber interface.

[0047] Block 709 may digitally sum signals from the radio heads which belong to the same beam based on the maintained beams-to-radio-heads mapping. In simple deployments, each beam may correspond to only one radio head and block 709 may not need to perform any function.

[0048] For every beam’s digital signals, block 708 may perform an FFT and convert the time-domain signals into frequency-domain signals.

[0049] Block 707 may use eCPRI protocol and report each beam’s I / Q signals to the 0-RAN DU via CU planes based on 0-RAN specifications. Block 707 may use an SFP module to send this data.IV. Example Operations

[0050] Figure 8 is a flow chart 800 illustrating an example embodiment. The process illustrated by Figure 8 may be carried out by a computing device, such as any of the computing components or systems described herein (e.g., of Figure 6). However, the process can be carried out by other types of devices or device subsystems. The embodiments of Figure 8 may be simplified by the removal of any one or more of the features shown therein. Further, these embodiments may be combined with features, aspects, and / or implementations of any of the previous figures or otherwise described herein.

[0051] Block 802 may involve retrieving, by a distribution unit of a radio network, predefined beam information for one or more circular radio frequency beams.

[0052] Block 804 may involve providing, by the distribution unit, in-phase and quadrature frequency domain signals of the one or more circular radio frequency beams to an access unit of the radio network.

[0053] Block 806 may involve using, by the access unit, beam identifiers for each of the circular radio frequency beams to route digital downlink signals to one or more radio heads, wherein the digital downlink signals are based on the in-phase and quadrature frequency domain signals.

[0054] Block 808 may involve converting, by the one or more radio heads, the digital downlink signals into analog downlink signals.

[0055] Block 810 may involve providing, by the one or more radio heads, the analog downlink signals to antenna ports.

[0056] Some embodiments may involve converting, by the access unit, the in-phase and quadrature frequency domain signals into time domain signals, wherein the digital downlink signals incorporate the time domain signals.

[0057] In some embodiments, a predefined beams-to-radio-heads mapping associates identifiers of the circular radio frequency beams to identifiers of the one or more radio heads.

[0058] In some embodiments, the predefined beams-to-radio-heads mapping is updated based on a time of day or day of week.

[0059] Some embodiments may involve amplifying, by the one or more radio heads, the analog downlink signals.

[0060] In some embodiments, beamforming and phase-shifting of downlink signals is omitted.

[0061] In some embodiments, routing the digital downlink signals to the one or more radio heads comprises routing each of the digital downlink signals to specific ones of the radio heads based on identifiers of the circular radio frequency beams.

[0062] In some embodiments, routing the digital downlink signals to the one or more radio heads comprises routing each of the digital downlink signals to all of the radio heads, and wherein the radio heads filter out some of the digital downlink signals based on identifiers of the circular radio frequency beams.

[0063] In some embodiments, providing the analog downlink signals to the antenna ports causes one or more antennas to transmit the analog downlink signals to one or more units of user equipment.

[0064] In some embodiments, the one or more antennas are configured to define the circular radio frequency beams.

[0065] Figure 9 is a flow chart 900 illustrating an example embodiment. The process illustrated by Figure 9 may be carried out by a computing device, such as any of the computing components or systems described herein (e.g., of Figure 6). However, the process can be carried out by other types of devices or device subsystems. The embodiments of Figure 9 may be simplified by the removal of any one or more of the features shown therein. Further, these embodiments may be combined with features, aspects, and / or implementations of any of the previous figures or otherwise described herein.

[0066] Block 902 may involve receiving, by one or more radio heads and by way of one or more antennas, uplink analog signals by way of circular radio frequency beams.

[0067] Block 904 may involve converting, by the one or more radio heads, the uplink analog signals into digital uplink signals.

[0068] Block 906 may involve providing, by the one or more radio heads, the digital uplink signals to an access unit of a radio network.

[0069] Block 908 may involve summing, by the access unit, the digital uplink signals from different ones of the radio heads corresponding to common circular radio frequency beams.

[0070] Block 910 may involve converting, by the access unit and for each of the common circular radio frequency beams, the digital uplink signals from a time domain to a frequency domain.

[0071] Block 912 may involve providing, by the access unit, frequency domain information for each of the common circular radio frequency beams to a distribution unit of the radio network.

[0072] Some embodiments may involve retrieving, by the distribution unit, predefined beam information for the circular radio frequency beams.

[0073] Some embodiments may involve amplifying, by the one or more radio heads, the analog uplink signals.

[0074] In some embodiments, providing the frequency domain information comprises providing in-phase and quadrature signals corresponding to the frequency domain information.

[0075] In some embodiments, a predefined beams-to-radio-heads mapping associates identifiers of the circular radio frequency beams to identifiers of the one or more radio heads.

[0076] In some embodiments, the predefined beams-to-radio-heads mapping is updated based on a time of day or day of week.

[0077] In some embodiments, summing the digital uplink signals is based on the predefined beams-to-radio-heads mapping.

[0078] In some embodiments, the uplink analog signals are received from one or more units of user equipment.

[0079] In some embodiments, the one or more antennas are configured to define the circular radio frequency beams.V. Example Technical Improvements

[0080] The proposed system and methods offer several significant technical improvements over traditional massive MIMO and beamforming technologies, particularly in specialized deployment environments. By utilizing circular beams that are spatially distributed over an area, the system eliminates the need for the extensive computational power and complex electronic circuitry typically required to perform phase-shifting and weight vector calculations for narrow directional signals. This reduction in complexity allows a gNB toachieve high throughput and frequency reuse while supporting smaller 2x2 or 4x4 MIMO antenna arrays, which are substantially reduced in size and weight compared to 16x16 massive MIMO arrays. These improvements specifically address the physical and computational constraints that make massive MIMO unsuitable for use inside buildings or in tunnels.

[0081] Furthermore, the implementation of circular beams provides superior coverage reliability in challenging environments where narrow beams are prone to failure. In tunnel deployments, circular beams distributed linearly provide consistent coverage to UEs distributed in one dimension, avoiding the issue where a narrow beam targeted at one UE passes through and interferes with others. In office buildings or manufacturing facilities, these circular beams mitigate the risk of signal loss caused by narrow beams being easily blocked or attenuated by walls and machinery. The technology also fits into the O-RAN architecture by utilizing the AU to maintain a beams-to-radio-heads mapping, which can be dynamically updated based on time of day or intelligent algorithms to balance or improve handling of traffic load. By simply enhancing AU function, circular beams can be easily applied into existing DAS deployments without the delays and complexities of more significant upgrades. This architecture allows for efficient routing or broadcasting of digital signals to radio heads without requiring the UE to change its standard feedback procedures, as the UE receives beam IDs and measures signal quality generally as it would with traditional narrow beams.VI. Conclusion

[0082] The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from its scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those described herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims.

[0083] The above detailed description describes various features and operations of the disclosed systems, devices, and methods with reference to the accompanying figures. The example embodiments described herein and in the figures are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations.

[0084] With respect to any or all of the message flow diagrams, scenarios, and flow charts in the figures and as discussed herein, each step, block, operation, and / or communication can represent a processing of information and / or a transmission of information in accordance with example embodiments. Alternative embodiments are included within the scope of these example embodiments. In these alternative embodiments, for example, operations described as steps, blocks, transmissions, communications, requests, responses, and / or messages can be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved. Further, more or fewer blocks and / or operations can be used with any of the message flow diagrams, scenarios, and flow charts discussed herein, and these message flow diagrams, scenarios, and flow charts can be combined with one another, in part or in whole.

[0085] A step, block, or operation that represents a processing of information can correspond to circuitry that can be configured to perform the specific logical functions of a herein-described method or technique. Alternatively or additionally, a step or block that represents a processing of information can correspond to a module, a segment, or a portion of program code (including related data). The program code can include one or more instructions executable by a processor for implementing specific logical operations or actions in the method or technique. The program code and / or related data can be stored on any type of computer-readable medium such as a storage device including RAM, a disk drive, a solid state drive, or another storage medium.

[0086] Moreover, a step, block, or operation that represents one or more information transmissions can correspond to information transmissions between software and / or hardware modules in the same physical device. However, other information transmissions can be between software modules and / or hardware modules in different physical devices.

[0087] The particular arrangements shown in the figures should not be viewed as limiting. It should be understood that other embodiments can include more or less of each element shown in a given figure. Further, some of the illustrated elements can be combined or omitted. Yet further, an example embodiment can include elements that are not illustrated in the figures.

[0088] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purpose of illustration and are not intended to be limiting, with the true scope being indicated by the following claims.

Claims

CLAIMSWhat is claimed is:

1. A method comprising:retrieving, by a distribution unit of a radio network, predefined beam information for one or more circular radio frequency beams;providing, by the distribution unit, in-phase and quadrature frequency domain signals of the one or more circular radio frequency beams to an access unit of the radio network; using, by the access unit, beam identifiers for each of the circular radio frequency beams to route digital downlink signals to one or more radio heads, wherein the digital downlink signals are based on the in-phase and quadrature frequency domain signals;converting, by the one or more radio heads, the digital downlink signals into analog downlink signals; andproviding, by the one or more radio heads, the analog downlink signals to antenna ports.

2. The method of claim 1, further comprising:converting, by the access unit, the in-phase and quadrature frequency domain signals into time domain signals, wherein the digital downlink signals incorporate the time domain signals.

3. The method of claim 1, wherein a predefined beams-to-radio-heads mapping associates identifiers of the circular radio frequency beams to identifiers of the one or more radio heads.

4. The method of claim 3, wherein the predefined beams-to-radio-heads mapping is updated based on a time of day or day of week.

5. The method of claim 1, further comprising:amplifying, by the one or more radio heads, the analog downlink signals.

6. The method of claim 1, wherein beamforming and phase-shifting of downlink signals is omitted.

7. The method of claim 1, wherein routing the digital downlink signals to the one or more radio heads comprises routing each of the digital downlink signals to specific ones of the radio heads based on identifiers of the circular radio frequency beams.

8. The method of claim 1, wherein routing the digital downlink signals to the one or more radio heads comprises routing each of the digital downlink signals to all of the radio heads, and wherein the radio heads filter out some of the digital downlink signals based on identifiers of the circular radio frequency beams.

9. The method of claim 1, wherein providing the analog downlink signals to the antenna ports causes one or more antennas to transmit the analog downlink signals to one or more units of user equipment.

10. The method of claim 9, wherein the one or more antennas are configured to define the circular radio frequency beams.

11. A method comprising:receiving, by one or more radio heads and by way of one or more antennas, uplink analog signals by way of circular radio frequency beams;converting, by the one or more radio heads, the uplink analog signals into digital uplink signals;providing, by the one or more radio heads, the digital uplink signals to an access unit of a radio network;summing, by the access unit, the digital uplink signals from different ones of the radio heads corresponding to common circular radio frequency beams;converting, by the access unit and for each of the common circular radio frequency beams, the digital uplink signals from a time domain to a frequency domain; and providing, by the access unit, frequency domain information for each of the common circular radio frequency beams to a distribution unit of the radio network.

12. The method of claim 11, further comprising:retrieving, by the distribution unit, predefined beam information for the circular radio frequency beams.

13. The method of claim 11, further comprising:amplifying, by the one or more radio heads, the analog uplink signals.

14. The method of claim 11, wherein providing the frequency domain information comprises providing in-phase and quadrature signals corresponding to the frequency domain information.

15. The method of claim 11, wherein a predefined beams-to-radio-heads mapping associates identifiers of the circular radio frequency beams to identifiers of the one or more radio heads.

16. The method of claim 15, wherein the predefined beams-to-radio-heads mapping is updated based on a time of day or day of week.

17. The method of claim 15, wherein summing the digital uplink signals is based on the predefined beams-to-radio-heads mapping.

18. The method of claim 11, wherein the uplink analog signals are received from one or more units of user equipment.

19. The method of claim 11, wherein the one or more antennas are configured to define the circular radio frequency beams.

20. A system including:one or more radio heads;an access unit communicatively coupled to the one or more radio heads; and a distribution unit communicatively coupled to the access unit, wherein the system is configured to perform the operations of any one or more of claims 1-19.

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