The described invention relates to wireless communications, and more particularly to selecting which radio links multi-mode devices (e.g., user equipments or UEs) should use simultaneously even where the links can employ the same or different radio access technologies (RATs).
Acronyms used herein are listed below following the detailed description. As used herein, a multi-mode device may use more than one radio link simultaneously. Such links can employ the same or different radio access technologies (RATs), and may belong to the same or different cells/access points. For the case of multiple different RATs these may be embodied as hybrid networks which in some deployments combine loosely coupled technologies and in others more tightly integrated technologies. Some non-limiting examples include user equipments (UEs) equipped with 5th generation/new radio (5G NR) and with 4th generation/long term evolution (LTE) radios; or with 5G NR and Wi-Fi radios; or with 5G NR and LTE and Wi-Fi radios; or with LTE and Wi-Fi radios. Also the device may be using multi-connectivity within the 5G RAT, for example with two or more simultaneously active NR links. Furthermore the device may be using any of the mentioned link combinations together with sidelink-sidelink such as device-to-device (e.g., Bluetooth®).
5G NR is a new RAT being developed by the 3GPP organization to meet ever increasing demand for wireless communications and may operate on multiple frequency bands, for example the mmWave frequency band, generally 6 GHz and higher (even up to 100 GHz). Some of the 5G NR service targets are enhanced mobile broadband (eMBB) and massive machine-type communications (m-MTC) with ultra/high-reliability and ultra-low latency (URLLC or sometimes HRLLC).
Typically such capability of multi-link connectivity has been exploited for boosting capacity; throughput in a given time. Embodiments of these teachings look at multi-link connectivity from the perspective of increased reliability, and particularly to leveraging redundancy and diversity offered by the available multiple networks to improve reliability. A higher reliability, even up to the so-called ‘5-nines’ (99.999% reliability), may be required by emerging mission critical use cases for example in the areas of process automation, factory automation, remote control, assisted and autonomous vehicles, so-called cyber-physical systems (CPS), and other mission-critical applications. In 5G NR terminology this is referred to as URLLC or HRLLC. The 3GPP organization defines reliability as a composite metric of latency and packet loss ratio; the probability to transfer successfully X bytes within a certain delay budget. The metric threshold is not fixed for all use cases but the delay budget may be strict, for example 1 ms. Reliability for these teachings are consistent with the 3GPP definition.
A problem arises in that a mission-critical device which has several active radio links at its disposal would ideally be able to determine how to utilize those available links for ensuring the required level of reliability. For example, the link decision to meet a data reliability metric can be whether to use a single link or multiple links at any given time among the available links, or if there are 3 or more links available which two or more links will best meet the reliability metric. Of course reliability can be maximized in many cases by utilizing all available links simultaneously for data, but this is not practical when there are multiple multi-mode devices making similar decisions because even with multiple RATs on multiple frequency bands the amount of radio spectrum remains a limited resource and so must be used efficiently. Further, also UE battery consumption is impacted by using multiple links at the same time. So the decision is to choose which link or links for sending the data to meet the reliability metric in a spectrum-efficient manner and/or battery efficient manner. In some instances simultaneously using a LTE link along with a 5G NR link will be the most spectrum-efficient choice to meet a given reliability metric, while in other instances that combination will not meet the reliability constraints and 2 5G NR links in addition to a WLAN/Wi-Fi link is the best choice.
This is not to say that all the UE's data is always transmitted on each and every one of the selected multiple links; there are a variety of ways to employ transmission redundancy short of wholesale duplicated transmissions on parallel channels. Sometimes this may be how the redundancy is implemented, while in other cases one of the links in a tightly-coupled network for example is utilized only for lower layer reliability improvement, e.g. via HARQ re-transmissions or HARQ incremental redundancy transmissions and control signaling. There is a wide variety of ways to implement redundancy when multiple links are in simultaneous use.
While the inventors are not aware of research or solutions specific to choosing what link combination will meet a reliability metric, some relevant teachings may be seen in the following references:
Further relevant background includes the IETF multi-path transmission control protocol (MP-TCP) which uses TCP properties to infer path properties including round-trip time (RTT) estimation to make forwarding decisions. In general latency is one of the fundamental properties of network paths because it has an impact to retransmissions, protocol performance, and network congestion. Latency estimates can also be used in dual connectivity flow control algorithms that determine how to route each packet on the link with the shortest delay. Further, it is known that in-band measurements often use built-in capabilities of TCP/IP such as the Internet control message protocol (ICMP) echo facility for assessing reachability and latency, and timestamp requests. Traditional QoS parameters are recognized as uplink (UL) and downlink (DL) maximum/guaranteed flow or bit rate, packet delay budget, packet error rate, and allocation and retention priority (ARP) among others. Document 3GPP TR 23.799 defines for 5G also the parameter “notification control” which is intended as notification between the radio access network (RAN) and the core network if the QoS targets are no longer being fulfilled for a QoS flow. Mechanisms related to the notification and how to minimize the notifications to the core network are yet to be determined as 5G is still under development, but the idea of the notification control is to inform the core network of the QoS shortfall so the core network can initiate some corrective modification.
According to a first aspect of these teachings there is a method comprising: determining a reliability target for radio communications, computing a first single multi-link reliability metric with a multi-mode device across a first set of multiple radio links that are simultaneously active for the multi-mode device. In the examples herein the single multi-link reliability metric enumerates an overall probability to successfully communicate a certain volume of digital data within a certain time constraint. Further in the method there is a comparing of the first single multi-link reliability metric to the reliability target, and in response to that comparing the method follows up with signaling the multi-mode device with an indication of the first set of multiple radio links that if utilized by the multi-mode device simultaneously would satisfy the reliability target, and/or with a notification of the single multi-link reliability metric associated with the first set.
According to a second aspect of these teachings there is an apparatus comprising at least one computer readable memory storing computer program instructions and at least one processor. The computer readable memory with the computer program instructions is configured, with the at least one processor, to cause the apparatus to at least determine a reliability target for radio communications, and compute a first single multi-link reliability metric with a multi-mode device across a first set of multiple radio links that are simultaneously active for the multi-mode device. The memory with the program instructions and the at least one processor is further configured to cause the apparatus to compare the first single multi-link reliability metric to the reliability target; and in response to the comparing these components further cause the apparatus to perform at least one of a) signaling the multi-mode device an indication of the first set of multiple radio links that if utilized by the multi-mode device simultaneously would satisfy the reliability target, and b) signaling the multi-mode device a notification of the single multi-link reliability target.
According to a third aspect of these teachings there is a computer readable memory storing computer program instructions that, when executed by one or more processors, cause a host device, such as for example a master radio access node operating with (at least) a first RAT, to perform actions comprising: determining a reliability target for radio communications, and computing a first single multi-link reliability metric with a multi-mode device across a first set of multiple radio links that are simultaneously active for the multi-mode device. A further action is to compare the first single multi-link reliability metric to the reliability target; and in response to the comparing thee is a yet further action which is at least one of a) signaling the multi-mode device an indication of the first set of multiple radio links that if utilized by the multi-mode device simultaneously would satisfy the single multi-link reliability target, and b) signaling the multi-mode device a notification of the single multi-link reliability metric associated with the first set.
According to a fourth embodiment from the perspective of the multi-mode device, there is an apparatus comprising at least one computer readable memory storing computer program instructions and at least one processor. The computer readable memory with the computer program instructions is configured, with the at least one processor, to cause a multi-mode device such as a user equipment to at least: receive from a radio network signaling that indicates at least a set of multiple radio links; and in response to receiving the signaling, use simultaneously the said set of multiple radio links to send data to the radio network. Further embodiments from this perspective include a method for performing the above steps as well as a computer readable memory storing a program of executable instructions that when executed cause a multi-mode device to perform such actions.
These and other aspects are detailed below with particularity.
Consider again the example radio environment of
As outlined in the background section above, the multi-link decision is generally about whether to use a single link or multiple links at any given time among the available ones, and if multiple links which ones. Consider how complex that would be for the radio environment of
This means that in any scenario where at least one of the multiple radio links available to the device uses non-scheduled operations, the UE will have to determine the uplink transmission mode/links. Consider the example of LTE-WLAN aggregation (LWA) where the uplink transmission mode is to be largely controlled by the UE in that it is the UE that determines, based on its own logic, how to serve the traffic via LTE and/or via WLAN. The network provides only a threshold depending on the UE's amount of buffered data to indicate when the UE can start using a split bearer, i.e. splitting/aggregating the data belonging to one bearer across LTE and WLAN interfaces (and in principle could also release the LWA configuration altogether in case of poor performance).
UE-controlled and best-effort mechanisms to control the use of the active radio links, such as those above, is acceptable as long as the objective of the network interworking is capacity boosting in a best effort fashion. But in truth giving the UE a role in deciding which radio link on which to place its data may result, and in the inventors' opinion likely will result, in a sub-optimal use of network resources for the simple fact that the UE may not necessarily know or be able to compute the quality of a given link, such as for example the link delay of packets sent over that link. On the contrary, if the objective of the multi-link connectivity is to ensure a given reliability level, some different or additional mechanisms are required based on the measurement of the actual level of fulfilment of reliability. Where there is the possibility of non-scheduled operations such as grant-free uplink resource allocations mentioned above, these mechanisms need to consider also the most efficient provisioning of network resources to meet those targets.
Embodiments of the teachings below address these limitations, and provide methods and mechanisms for reliability-based multi-link decisions that are most advantageously deployed for mission critical devices. More specifically, the detailed examples below provide a method for reliability-based dynamic selection of one or more radio links for mission critical/high reliability services. As will be seen, this method can be applied either as network-controlled or network-assisted, depending on the assumed level of radio signaling and UE autonomy.
The reader will notice the following aspects of this method:
The simultaneous use of multiple links in transmission means that the sending of an element of data for which the reliability metric is defined (such as a PDU or a message for example) is using the links in the set for that element of data. As mentioned above there are many different ways to send such an element of data over the multiple links and in further examples below the particular way a given element of data is sent is dependent on the transmission mode. For example, the element of data can be bi-cast or multi-cast on the multiple links of a given set. In some transmission modes the element of data can be sent on different links at the same instant in time, or there may be a delay between one link and another of the set of multiple links, or there may not be a time correlation for sending the element of data on those links. Typically the reliability metric will depend on the transmission mode being used for the multiple link set, not least because there is a delay budget or time aspect to the reliability metric and some of the different transmission modes may have different time relationships between the element of data sent on the different links.
These main aspects are detailed further below. For a wide scale implementation across multiple different RATs certain aspects of these teachings are best standardized, for example in a published radio standard for 5G NR. For example, the radio resource control (RRC) signalling and/or the 5G NR PDAP aspects can be standardized since those are the means to transfer to the UE the indication/notification detailed herein. Legacy systems such as LTE and WLAN can also adopt these in standardized form or they may realize these teachings in an implementation specific manner, preferably once they are standardized for 5G NR or some other public documentation.
Above it is described the network computes the multi-link reliability metric. While embodiments of these teachings encompass multiple links over multiple different networks using different RATs, the ‘network’ performing the steps according to these teachings refers what may be considered a master node. While this may be known by a different name in certain deployments of these teachings, in function the master node refers to the network entity that has a certain level of control over all the links involved in the radio communications towards the UE and this master node is connected via well defined network interfaces to the other cells/access points/radio access nodes involved in the multi-connectivity communications. For instance, such a master node also takes care of data combining (e.g. reordering) the data that is sent from the UE via the different multiple uplinks. Such a master node can compute the single reliability metric based on all the acquired information from the multiple UEs being served, which report measurements related to all the networks/links, and the master node can further acquire the information needed to compute the multi-link reliability metric via direct exchange with the other network nodes/cells/links. As one example, during the early deployments of 5G NR when that RAT is not yet capable of standing alone the LTE eNB may serve as the master node in a LTE-5G NR interworking that serves a given UE, while in later deployments when 5G NR is fully capable of operating independently of other RATs the tight interworking may have the gNB acting as the master node to the LTE and WLAN AP ‘slave’ nodes while the multi-mode device (UE) has distinct but inter-worked uplinks with the gNB, the eNB and the WLAN AP simultaneously.
In one embodiment the achieved one/single reliability metric is computed so as to account for application and protocol performance based on each packet of a UE's data traffic, or each packet within a flow, or any packet of a given application or the entire “critical message” of a given application. What is a “message” would depend on the protocol used, and could be constructed based on inspecting packet headers via so called in-band measurements. So the granularity would depend on traffic profiling capabilities at the network side e.g. in identifying certain traffic types and application protocols, IP addresses, and so forth. In another embodiment the achieved reliability is computed on probabilistic terms, for example the measurement data is based only on a subset of packets or flows and that measurement data is extrapolated to the whole data flow.
The network (specifically, the master node) tracks the UE's data in the flow on the multi-links against the reliability metric at block 304. If the reliability target is met (or in some deployments if it is also expected to continue to be met, so for example the measured reliability is not degrading when it is within some threshold limit of the reliability target) then the
In certain embodiments for the network controlled approach of
There are a variety of options for the network to signal at block 308 the indication of the multi-link combination(s) the UE should use to support the required single-metric reliability target. Such an indication could be provided along with the notification to the UE of reliability degradation or a failure to fulfill the reliability metric which may require the UE to utilize more links in order to still meet the reliability metric. In some embodiments the network will inform the UE that reliability has increased by at least some minimal amount which may enable the UE to utilize fewer links while still meeting the reliability metric; in this case the indication can be provided with the information about the reliability increase. In some embodiments the indication of block 308 can be provided in a scheduling grant that allocates uplink and/or downlink radio resources to the UE.
In some embodiments this indication at block 308 could indicate the transmission mode the UE is to use. A transmission mode for a given set of multi-link defines how to use each of the links composing the set to serve the UE's data for a certain data flow/bearer. Some examples of this transmission mode signaled to the UE include, but are not limited to:
In some embodiments the network at block 306 may find that there are multiple selections of multi-links sets that are estimated to meet the single reliability metric. In this case the network may inform the UE of only one of them as above, or it may inform the UE of two or more such selections and allow the UE to make the final choice among that very limited set of multi-link options the network presents to the UE. This embodiment may be considered a hybrid between the network-controlled approach of
In certain embodiments for the network assisted approach of
In another embodiment, the one single reliability value is provided on a per bearer/flow (IP flow or QoS flow) granularity, and/or per traffic type. These are again different from individual reliability metrics per radio link since in this case there is one metric per multi-link combination. In another embodiment the network may provide to the UE/multilink device the indication that reliability is degrading for a certain bearer or flow and that it is degrading with a certain degradation delta (rate of change) as compared to the target.
There are quite a variety of options for the network to signal the reliability metric to the UE at block 310. For example the notification of the single multi-link metric expressing the reliability level reached or predicted in the future by the combined usage of multi-link(s) for a certain bearer/QoS flow can be provided in an existing signaling messages (for example, a new information element in an existing RRC message or an entirely new signaling message), or in-band using information elements in the user-plane packet headers (for example, a new dedicated field in the 5G NR PDCP header), or piggy-backed to the downlink data payload sent to the UE (for example at the NR PDAP layer, at the TCP/IP layer, or in an application protocol). The network may provide this notification conditional on the result of the comparison at block 3043 as
Certain of the embodiments of these teachings provide the technical effect of ensuring that the required level of reliability is provided and enabling an effective reaction to situations where violation of the requirements are measured or anticipated. More broadly stated, one technical effect is that these teachings support/enable mission-critical/high reliability applications.
Consider a few practical examples how these teachings may advantageously be deployed. Assume a mission critical device has multiple radio links which may have different underlying RATs such as NR-LTE, NR-WLAN and LTE-WLAN. If the reliability level is signaled to the UE per block 310 of
In one example, if 5G NR is one of the available radio links then sustaining the needed reliability would benefit from a fast switch between using non-scheduled operations versus using scheduled operations over the 5G NR link in addition to one or more secondary link. Ideally the non-scheduled operations should be minimized due to inherent radio spectrum efficiency costs these entail, for example due to the procedures they use to minimize collisions in the pre-reserved resources, as well as due to the QoS degradation costs in case collisions occur. In another example when a wireless hybrid network that includes legacy wireless systems is used to provide high reliability, in-band indications of the achieved reliability can be provided to the UE (for example, in the TCP/IP header) with minimal impact to the UE, and these in-band indications could assist the UE in future multi-link decisions. As final examples, autonomous driving and control of drones are mission critical applications for which failure to meet reliability targets can have serious consequences. Applications for autonomous driving or drone control can benefit from adopting these teachings in that guaranteeing the necessary reliability is a direct improvement to the safe operation of the system.
As a review of some of the above more detailed examples, in one embodiment there is a method comprising determining a reliability target for radio communications. The network also computes a first single multi-link reliability metric with a multi-mode device across a first set of multiple radio links that can be used simultaneously for the multi-mode device. As detailed more particularly above, the single multi-link reliability metric enumerates an overall probability to successfully communicate a certain volume of digital data within a certain time constraint. Block 302 of
In one particular deployment of these teachings the first set of multiple radio links includes a first link utilizing a first radio access technology such as 5G NR or LTE and a second link utilizing a different second radio access technology such as the other of 5G NR or LTE. Some RATs have non-scheduled operations and so if we assume the second RAT is for example Wi-Fi (formally, IEEE 802.11) and the first RAT is LTE, (at least some of) the radio communications on the first link are scheduled by resource grants to the multi-mode device and (at least some of) the radio communications on the second link are not scheduled by resource grants to the multi-mode device. This may also be at least partly true if 5G NR is the second RAT if it comes to pass that 5G NR is deployed to allow certain resources to be set aside in advance for non-scheduled operations.
These teachings may be deployed to advantage specifically when there is a mission critical application, in which case the reliability target may be determined based on that application which is deemed to be mission critical. The radio communications at issue may be categorized as, or consist of, a QoS flow or an IP flow for the multi-mode device.
Now consider an example where the network also computes a second single multi-link reliability metric with a multi-mode device across a second set of multiple radio links that can be used simultaneously for the multi-mode device. In this case the first set and the second set may or may not be overlapping in that there may or may not be at least one radio link in common between these two sets. In this case the network would also compare the second single multi-link reliability metric to the reliability target. Only if the comparing shows that the reliability target would be satisfied by the first single multi-link reliability metric would the network send to the multi-mode device the indication of the first set and/or the notification of the single multi-link reliability metric associated with the first set. Further, if this further comparing shows that the reliability target would not be satisfied by the second single multi-link reliability metric then the network would not send to the multi-mode device an indication of the second set and/or a notification of the single multi-link reliability metric associated with the second set, but in some embodiments if that further comparing shows the reliability target would be satisfied by the second reliability metric then the network may send to the device the indication of the second set and/or the notification of the reliability metric associated with the second set, in addition to that of the first set.
If the UE was previously using a first multi-link set, and the network wants to indicate a second multi-link set to the UE, the network may do so in incremental fashion, by signaling which links should no longer be used and/or which links should be additionally used. So for example if we assume the UE's initial multi-link set that includes links A, B, C and D begins to deteriorate, the network can indicate a first multi-link set {A, B, D, E} to the UE by signaling it to drop link C and add link E and at some later time can indicate a second multi-link set {D, E, F} to the UE by signaling it to drop links A and B and add link F. In more general terms this can be regarded as the network signaling the indication of the first set of multiple radio links by identifying only incremental differences over a previous set of multiple radio links that the first set is to replace. The signaling for the first set is coded with reference to the previous set.
As further detailed above, in some embodiments the indication or notification comprises a dedicated field in a header of a user-plane data packet, and/or a control plane message such as a radio resource control (RRC) message and/or an information element within a RRC message. In addition to this indication/notification, the network can in some embodiments also send the multi-mode device further information about the comparing done at block 304 of
The above examples detailed that the computing and the comparing and the signaling are done in response to the network determining that the current radio communications with the multi-mode device do not satisfy the reliability target, or is anticipated to not satisfy the reliability target. And in some further embodiments, when the network signals the device with the indication or the notification the network may also send to the device/UE information about transmission mode to use for the radio communications. Many such transmission mode examples are set forth in a bulleted list above.
Various of these aspects may be practiced individually or in any of various combinations. While the above description of
As an example of such corresponding behavior on the part of the UE 10, there may be an apparatus (such as the multi-mode device itself or components thereof) that comprises at least one computer readable memory storing computer program instructions, and at least one processor as detailed below for the UE 10 of
As detailed more fully above, in an advantageous deployment the received signaling indicates a first set of multiple radio links and further indicates a second set of multiple radio links and also information that the first set and the second set each meet a reliability target (these reliability targets may differ for the different sets, so there is a first reliability target associated with the first set and a second reliability target associated with the second set). In this embodiment, further in response to receiving the signaling the multi-mode device selects from among the first and second sets based on at least one performance criteria such as for example optimizing power consumption at the multi-mode device. The set of multiple radio links that the device uses simultaneously to send data to the radio network is therefore the selected first set or second set.
In a particular embodiment in which the set of multiple radio links is a first set and the received signaling further indicates a first single multi-link reliability metric associated with the first set, the computer readable memory with the computer program instructions is configured with the at least one processor to cause the multi-mode device to further receive from the radio network a) an indication that the first single multi-link reliability metric associated to the first set does not satisfy a reliability target or is anticipated to not satisfy the reliability target; and b) a second set of multiple radio links and an associated second single multi-link reliability metric that satisfies the reliability target. In this particular embodiment, in response to the further signaling the multi-mode device receives the device changes from the first set to the second set for continued communications with the radio network. To be clear, the first set and the second set are not identical.
In another particular embodiment the received signaling further indicates directly a transmission mode the multi-mode device is to adopt when using simultaneously the said set of multiple radio links to send data to the radio network. In some instances the network can signal this with the set of multiple radio links, or in other instances the network can signal this separately in which case the multi-mode device can continue using its current set of links but with the changed transmission mode so as to continue meeting the reliability target. If the network is signaling to the device the reliability metric for a given set of links, then in the latter case the network may also signal a new reliability metric associated with the current set and the newly signaled transmission mode since changing the transmission mode would yield a different reliability metric.
The above actions described from the perspective of the multi-mode device as apparatus can also be embodied in a practical deployment as a method, and/or as a computer readable memory storing computer program instructions that, when executed by one or more processors, cause a multi-mode device to perform those described actions.
The UE 10 includes a controller, such as a computer or a data processor (DP) 414 (or multiple ones of them), a computer-readable memory medium embodied as a memory (MEM) 416 (or more generally a non-transitory program storage device) that stores a program of computer instructions (PROG) 418, and a suitable wireless interface, such as multiple radio frequency (RF) transceivers or more generically radios 412, for bidirectional wireless communications with the gNB 25 and the eNB 20 via one or more antennas. In general terms the UE 10 can be considered a machine that reads the MEM/non-transitory program storage device and that executes the computer program code or executable program of instructions stored thereon. While each entity of
In general, the various embodiments of the UE 10 can include, but are not limited to, mobile user equipments or devices having wireless communication capabilities, including smartphones, wireless terminals, portable computers, image capture devices, gaming devices, music storage and playback appliances, Internet appliances, machine-type communication devices, vehicle-mounted internet devices, smart-home/Internet-of-Things type devices, as well as portable units or terminals that incorporate wireless communications capabilities.
The gNB 25 also includes a controller, such as a computer or a data processor (DP) 424 (or multiple ones of them), a computer-readable memory medium embodied as a memory (MEM) 426 that stores a program of computer instructions (PROG) 428, and a suitable wireless interface, such as a RF transceiver or radio 422, for communication with the UE 10 via one or more antennas. The gNB 25 is coupled via a data/control path 434 to the core network/S-GW 40. The path 434 may be implemented as a RAN-CN interface. The gNB 25 may also be coupled to other radio network access nodes operating with the same first RAT via another interface.
The gNB 25 may further be coupled to a second network access node such as the eNB 20 operating with a different second RAT via a data/control path 436 which may be implemented as a wired or wireless Xn interface. Relevant components of the eNB 20 are substantially similar to those detailed for the gNB 25 and so are not repeated, except to note that the gNB 25 operates at much higher frequencies than the eNB 20, typically will have a much higher number of antennas, and is anticipated to be dispersed in that the antennas are disposed at remote radio heads (RRHs) that are remote from the baseband processing functionality (one or more baseband units BBUs). Both the RRHs and the BBUs will each have their own data processor DP and computer-readable memory MEM storing programs of computer instructions PROGs, but the majority of memory and processing capability is to be in the BBUs of the gNB 25.
Referring again to the first RAT/5G NR system, the core network 40 includes a controller, such as a computer or a data processor (DP) 444 (or multiple ones of them), a computer-readable memory medium embodied as a memory (MEM) 446 that stores a program of computer instructions (PROG) 448.
At least one of the PROGs 418, 428 (and also in the eNB 20) is assumed to include program instructions that, when executed by the associated one or more DPs, enable the device to operate in accordance with exemplary embodiments of this invention. That is, various exemplary embodiments of this invention may be implemented at least in part by computer software executable by the DP 414 of the UE 10; and/or by the DP 424 of the gNB 25 or of the eNB 20; and/or by hardware, or by a combination of software and hardware (and firmware).
For the purposes of describing various exemplary embodiments in accordance with this invention the UE 10 and the gNB 25 (as well as the eNB 20) may also include dedicated processors 415 and 425 respectively. There may also be dedicated processors in either or both of the RRHs and the BBUs of the gNB 25.
The computer readable MEMs 416, 426, 446 and also of the eNB 20 may be of any memory device type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The DPs 414, 424, 444 and also of the eNB 20 may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on a multicore processor architecture, as non-limiting examples. The wireless interfaces (e.g., RF transceivers 412 and 422 and of the eNB 20) may be of any type suitable to the local technical environment and may be implemented using any suitable communication technology such as individual transmitters, receivers, transceivers or a combination of such components.
A computer readable medium may be a computer readable signal medium or a non-transitory computer readable storage medium/memory. A non-transitory computer readable storage medium/memory does not include propagating signals and may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Computer readable memory is non-transitory because propagating mediums such as carrier waves are memoryless. More specific examples (a non-exhaustive list) of the computer readable storage medium/memory would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
It should be understood that the foregoing description is only illustrative. Various alternatives and modifications can be devised by those skilled in the art. For example, features recited in the various dependent claims could be combined with each other in any suitable combination(s). In addition, features from different embodiments described above could be selectively combined into a new embodiment. Accordingly, the description is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.
A communications system and/or a network node/base station may comprise a network node or other network elements implemented as a server, host or node operationally coupled to a remote radio head. At least some core functions may be carried out as software run in a server (which could be in the cloud) and implemented with network node functionalities in a similar fashion as much as possible (taking latency restrictions into consideration). This is called network virtualization. “Distribution of work” may be based on a division of operations to those which can be run in the cloud, and those which have to be run in the proximity for the sake of latency requirements. In macro cell/small cell networks, the “distribution of work” may also differ between a macro cell node and small cell nodes. Network virtualization may comprise the process of combining hardware and software network resources and network functionality into a single, software-based administrative entity, a virtual network. Network virtualization may involve platform virtualization, often combined with resource virtualization. Network virtualization may be categorized as either external, combining many networks, or parts of networks, into a virtual unit, or internal, providing network-like functionality to the software containers on a single system.
The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
AC access controller
AP access point
ARP allocation and retention priority
CN core network
CPS cyber-physical systems
D2D device to device
DL downlink
eNB evolved nodeB
gNB next generation radio access node (5G NB)
HARQ hybrid ARQ
IE information element
IEEE institute of electrical and electronics engineers (standardization body)
IETF internet engineering task force (standardization body)
HRLLC high reliability low latency communications
LTE long term evolution (of E-UTRA)
LWA LTE WLAN aggregation
MP-TCP multi-path TCP
NR new radio (also known as 5th Generation or 5G)
PDAP PDCP application protocol (?)
PDCP packet data convergence protocol (protocol layer)
PDU protocol data unit
QoS quality of service
RAN radio access network
RAT radio access technology
RRC radio resource control
RTT round trip time
SDU service data unit
TTI transmission time interval
UL uplink
UMTS universal mobile telecommunications service
URLLC ultra reliability low latency communications
WLAN wireless LAN
Xw interface between 3GPP eNB and WLAN Termination for LWA