GB2589111A

GB2589111A - Wireless telecommunications network

Info

Publication number: GB2589111A
Application number: GB1916887.1A
Authority: GB
Inventors: Mehran Farhad; Mackenzie Richard
Original assignee: British Telecommunications PLC
Current assignee: British Telecommunications PLC
Priority date: 2019-11-20
Filing date: 2019-11-20
Publication date: 2021-05-26
Anticipated expiration: 2039-11-20
Also published as: GB201916887D0; GB2589111B

Abstract

This invention provides a method of operating a wireless telecommunications network, the wireless telecommunications network having a first transceiver and second transceiver, the method comprising the steps of: i) identifying positional information of the first transceiver; ii) identifying a first spectral frequency of communications between the first and the second transceivers; iii) determining, based on the identified positional information, whether a natural environmental feature is present between the first and second transceiver, in which the natural environmental feature is associated with causing at least partial attenuation of wireless communications; iv) identifying, based on the identified first spectral frequency of step 11) and the determination of step iii), a reconfiguration operation to reconfigure a property of communications to the second transceiver; and v) initiating the reconfiguration operation. The property may be spectral frequency of communication, a change of position of either transceiver or a handover of a transceiver

Description

Field of the Invention

The present invention relates to a wireless telecommunications network.

Background

Wireless telecommunications networks include a plurality of computing devices that communicate using wireless transmissions. They include cellular telecommunication networks, wireless local area networks, wireless personal area networks, wireless ad hoc networks, and wireless wide area networks. The computing devices within any one of these wireless telecommunications networks include transceivers to communicate using electromagnetic waves, typically in the Radio Frequency (RF) part of the electromagnetic spectrum.

Wireless local area networks and cellular telecommunication networks traditionally use RF waves from around several hundred megahertz to around several gigahertz to communicate. Relatively low frequency communications have a greater range (due to the lower propagation losses experienced within the one or more transmission media) whereas relatively high frequency communications tend to have a greater data throughput (due to, for example, greater frequency reuse or by larger bandwidth channels). As users demand ever higher data rates, modern wireless telecommunications networks tend to employ increasingly high frequency communications (such as the Extremely High Frequency, EHF, part of the spectrum from thirty gigahertz to three-hundred gigahertz). However, if the consequent reduced range is not acceptable to the user, then the network operator must solve the range problem by, for example, increasing the transmit power of each transceiver or introducing more transceivers; however, these options are limited due to, for example, regulatory power limits and resource constraints of network operators respectively.

Summary of the Invention

According to a first aspect of the invention, there is provided a method of operating a wireless telecommunications network, the wireless telecommunications network having a first transceiver and second transceiver, the method comprising the steps of: i) identifying positional information of the first transceiver; ii) identifying a first spectral frequency of communications between the first and the second transceivers; iii) determining, based on the identified positional information, whether a natural environmental feature is present between the first and second transceiver, in which the natural environmental feature is associated with causing at least partial attenuation of wireless communications; iv) identifying, based on the identified first spectral frequency of step ii) and the determination of step iii), a reconfiguration operation to reconfigure a property of communications to the second transceiver; and v) initiating the reconfiguration operation.

The reconfiguration operation may be to reconfigure the second transceiver to communicate at a second spectral frequency, wherein the natural environmental feature may have a differential interference effect across the electromagnetic spectrum.

The reconfiguration operation may be to transfer the second transceiver from the first transceiver to a third transceiver, wherein communications between the second and third transceiver may be at the second spectral frequency.

The reconfiguration operation may be to reconfigure the first and second transceiver to communicate at the second spectral frequency.

The method may further comprise the step of: identifying positional information of the second transceiver, wherein step iii) may be based on the identified positional information of both the first and second transceiver.

The positional information may include altitude, may be only altitude, and may include longitude and/or latitude.

The reconfiguration operation may be to change a position of the first and/or second transceiver.

The reconfiguration operation may be to change a position of the third transceiver.

The first transceiver may be a base station and the second transceiver may be a User Equipment, UE. The third transceiver may be a base station.

The natural environmental feature may be an atmospheric source and/or physical source.

A magnitude of attenuation caused by the natural environmental feature may vary over a time period, and the reconfiguration operation may be further based on: the time of communications to the second transceiver; and the magnitude of attenuation caused by the natural environmental feature at said time.

The method may further comprise the initial step of: determining whether a previously applied reconfiguration operation improved communications, wherein step iii) and/or step iv) is further based on the determination of step vi).

According to a second aspect of the invention, there is provided a computer program product comprising instructions which, when executed on a computer, cause the computer to carry out the steps of the method of the first aspect of the invention. The computer program product may be stored on a computer-readable storage medium.

According to a third aspect of the invention, there is provided a network node comprising a processor configured to carry out the steps of the method of the first aspect of the invention.

Brief Description of the Figures

In order that the present invention may be better understood, embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic diagram of an embodiment of a wireless telecommunications network of the present invention; Figure 2 is a flow diagram illustrating an embodiment of a method of the present invention; Figure 3 is a schematic diagram of a cellular telecommunications network implementing the method of Figure 2, in a first state; Figure 4 is a schematic diagram of the cellular telecommunications network of Figure 3, in a second state; and Figure 5 is a schematic diagram of the cellular telecommunications network of Figure 3, in a third state.

Detailed Description of Embodiments

A first embodiment of a wireless telecommunications network will now be described with reference to Figure 1. In this first embodiment, the wireless telecommunications network is a cellular telecommunications network 1 having a first base station 10, a second base station 20 and a User Equipment (UE) 30. The first base station 10 and UE 30 are mobile such that their positions on and/or from the Earth's surface may change (e.g. due to self-powered motion or due to being positioned on a moving platform such as a train). The second base station 20 is fixed such that its position does not change. The first base station 10 and the UE 30 include Global Navigation Satellite System (GNSS) modules in order to determine their position On terms of GNSS coordinates) relative to the Earth's surface. The second base station 20 stores its GNSS coordinates in memory, which may be determined by a local GNSS module or may be recorded as a configuration parameter.

The first and second base stations 10, 20 and UE 30 have respective communications interfaces for wireless communications (including both inter-base station communications and communications between each base station and the UE). In this embodiment, these communications are based on the 5th Generation (5G) protocol as standardised by the 31dGeneration Partnership Project (3GPP), and therefore cover both the sub-six gigahertz band and the Extremely High Frequency, EHF, band (from around thirty gigahertz to around three hundred gigahertz).

The first and second base stations 10, 20 have backhaul connections to a cellular core network which includes a Self-Organising Network (SON) node 40. The SON node 40 includes an environmental feature database which stores data on natural environmental features that may be sources of attenuation for communications within the cellular telecommunications network 1. This data includes, for each environmental feature, the type of natural feature (e.g. trees, hills, clouds, fog, high atmospheric pressure, etc.), positional information on the natural feature (e.g. GNSS coordinates), and temporal characteristics of the natural feature. The SON node 40 also includes a reconfiguration function which determines, based on properties of a communication channel between a UE and serving base station and further based on environmental features being a source of attenuation to that communication channel, what reconfiguration operation should be performed to improve the quality of communications to the UE. This will be explained in more detail, below.

Figure 2 is a flow diagram illustrating a first embodiment of a method of the present invention, and Figures 3 to 5 illustrate first, second and third states of an example cellular telecommunications network implementing this first embodiment of the method. In the first state, as shown in Figure 3, the first base station 10 transmits a first beam which covers the position of the UE 30. The first beam uses the EHF band. The second base station 20 transmits about a coverage area (known as a "cell"), which is larger than the first base station's first beam and also covers the position of the UE 30. The second base station's coverage area uses the sub-six gigahertz band.

In this first state the UE 30 is being served by the first beam of the first base station 10 and therefore communications between the UE 30 and first base station 10 utilise the EHF band (supporting high data throughput). In a first iteration of the method of Figure 2, the UE 30 sends a location report to the first base station 10 (step Si). This location report includes positional information for the UE 30 including the longitude, latitude and/or height of the UE 10. On receipt, in step S3, the first base station 10 processes the location report from the UE 10 and its own positional information (i.e. its own longitude, latitude and height) to estimate a transmission region 15 of communications between the first base station 10 and UE 30.

In step S5, the first base station 10 sends a report to the SON node 40, identifying the estimated transmission region 15 between the first base station 10 and UE 30 and further identifying the frequency band for communications between the first base station 10 and UE 30 On this first state, the EHF band).

In step S7, the SON node 40 performs a lookup of its environmental feature database of all environmental features having a location within the estimated transmission region 15.

In step S9, the SON node 40 implements its reconfiguration function to determine whether a reconfiguration operation is required and, if so, what operation should be applied. The reconfiguration function utilises two inputs: 1) the environmental feature(s) identified as being present in the estimated transmission region between (in particular in terms of line of sight) a UE and its serving base station, and 2) the frequency band used in communications between the UE and its serving base station, to compute, as an output, a suitable reconfiguration operation from a set of reconfiguration operations. This set of reconfiguration operations include: 1) No reconfiguration required; 2) Transferring (e.g. handover or cell re/selection) the UE to a target base station in which communications utilise another frequency band (which may be to a neighbouring base station or to another beam/cell of the current serving base station); 3) Moving the serving base station and/or UE so that the environmental features are no longer positioned within the estimated transmission region between the serving base station and UE; 4) Transferring (e.g. handover or cell re/selection) the UE to a target base station being located in (or moved to) a location such that the environmental features are not positioned within the estimated transmitted region between the target base station and the UE; and 5) Reconfiguring the communication channel between the UE and the current serving base station to use an alternative frequency band (although consideration must be given for other UEs being served by that base station).

In this first iteration, the lookup operation of step S7 determines that there are no environmental features within the estimated transmission region 15 and, in step S9, the output of the reconfiguration function is that no reconfiguration operation should be performed, and the SON node 40 sends a message to the first base station 10 indicating that it should continue to use its current configuration. The process then loops back to step Si.

A second iteration of the method is performed at a subsequent time in which the cellular telecommunications network 1 is in a second state as shown in Figure 4. Steps Si to S5 are performed by the UE 30 and first base station 10. As the first base station 10 and UE 30 have moved and are in a different position (relative to the first state), then the estimated transmission region 15 defined in this second iteration is different to the estimated transmission region 15 of the first iteration. In step S7, the SON node 40 performs a lookup of its environmental feature database of all environmental features having a location within the estimated transmission region 15. In this second iteration, the data returned by the lookup indicates that heavy fog is present between the first base station 10 and UE 30. In step S9, SON node 40 implements its reconfiguration function to determine whether a reconfiguration operation is required and, if so, what operation should be applied. In this second iteration, the SON node 40 determines that the UE should be transferred from the first base station 10 to the second base station 20.

In step S11, SON node 40 sends a message to the first base station 10 to identify the selected reconfiguration operation. In step 513, the first base station 10 reacts to this message by performing the selected reconfiguration operation. Accordingly, the first base station 10 initiates a handover of the UE 30 so that it is served by the second base station 20 which utilises the sub-six gigahertz band, as per a third state of the cellular telecommunication network. This frequency band suffers less attenuation during propagation through the heavy fog and so communications are likely to have improved connectivity (e.g. better signal-to-noise ratio (SNR) and data throughput). This third state of the cellular telecommunications network is shown in Figure 5.

In step S15, the second base station 20 prepares a performance report indicating the performance of the connection with the UE 30. This performance report may be a simple indicator of whether or not a Radio Link Failure (RLF) event occurred within a particular time period following the reconfiguration operation, or may be more detailed to indicate, for example, one or more of: whether the connection achieved a target data throughput, whether the connection achieved a target error rate, and whether the connection achieved a target SNR. This performance report is sent to the SON node 40.

These performance reports may be received for each reconfiguration operation that is instructed by the SON node 40. This data indicates, for each reconfiguration operation, whether the selected reconfiguration operation was successful or not. The SON node 40 may therefore prepare training and validation data including, for each historical reconfiguration operation, the inputs to the reconfiguration function (e.g. the frequency band in use between the UE and serving base station, and the environmental feature(s) positioned between the UE and the serving base station), the output reconfiguration operation, and whether that output reconfiguration operation was successful or not. The training and validation data may be continually updated as further reconfiguration operations are performed and associated performance reports are received. Using this training and validation data, in step S17, the SON node 40 may perform a machine learning process to update its reconfiguration function and improve its performance (i.e. selecting the most appropriate reconfiguration operation for a given scenario). Alternatively, the reconfiguration function may be updated by an operative based on the same data.

As noted above, the environmental feature database identifies temporal characteristics of each environmental feature (i.e. where environmental features change over a period of time, such as deciduous trees which periodically shed their leaves). The SON node's reconfiguration function may then be configured to utilise three inputs, 1) the frequency band for communications between the UE and the serving base station, 2) environmental feature(s) positioned between the UE and the serving base station, and 3) current time, to output a suitable reconfiguration operation. In this manner, the selected reconfiguration operation may be suitable based on the time-varying nature of the environmental feature and the current time. For example, if the environmental feature is a group of deciduous trees that shed their leaves in the winter and the UE and serving base station communicate using the EHF band, then the reconfiguration function may output a different operation in the summer compared to the winter. In the summer, the reconfiguration operation could be to transfer to a target base station using the sub-six gigahertz band, whereas, in the winter, no reconfiguration operation is selected. These operations would be suitable for those times of year as the EHF band is less attenuated by trees without leaves than by trees with leaves.

In the above example, the SON node 40 determined that the UE 30 should be transferred to the second base station that utilises the sub-six gigahertz band. This reconfiguration was suitable for the scenario in which the UE 30 and first base station 10 were communicating using the EHF band and heavy fog was present between the UE 30 and first base station 10. In a subsequent iteration, the SON node 40 may determine that no environmental features are present between the UE 30 and second base station 20 (for example, if the heavy fog is no longer present). In this scenario, the SON node 40 may then determine that a suitable reconfiguration operation would be to transfer the UE 30 to a target base station that utilises the EHF band (so as to increase data throughput).

Accordingly, the reconfiguration operation is to select a frequency band to improve performance for the UE based on the presence of environmental features.

The SON node 40 of the first embodiment is a centralised network node having a database of natural environmental features. Some environmental features may be present at a particular location for a long period of time (e.g. hills or trees), but others may be changeable over a much smaller time scale (e.g. weather related features, such as clouds and fog). The SON node 40 may therefore receive updates on environmental features from, for example, a regional meteorological organisation, and store this data in its environmental features database. The SON node 40 may also utilise, for example, satellite data to determine the presence of environmental features (e.g. trees) in a particular location, and again store this data in its environmental features database. The skilled person will understand that this is just one implementation and it is possible for one or both of the environmental features database and reconfiguration function to be embodied on other nodes in the wireless telecommunications network (such as on the base station).

The skilled person will also understand that the present invention is not limited to cellular telecommunications networks, and may instead be applied to any form of wireless telecommunications network.

Furthermore, the skilled person will understand that it is non-essential that the positional information is based on height of the base station and/or UE. However, this may be useful in some scenarios such as, for example, providing wireless telecommunication services to aircraft.

Insofar as embodiments of the invention described are implementable, at least in part, using a software-controlled programmable processing device, such as a microprocessor, digital signal processor or other processing device, data processing apparatus or system, it will be appreciated that a computer program for configuring a programmable device, apparatus or system to implement the foregoing described methods is envisaged as an aspect of the present invention. The computer program may be embodied as source code or undergo compilation for implementation on a processing device, apparatus or system or may be embodied as object code, for example.

Suitably, the computer program is stored on a carrier medium in machine or device readable form, for example in solid-state memory, magnetic memory such as disk or tape, optically or magneto-optically readable memory such as compact disk or digital versatile disk etc., and the processing device utilises the program or a part thereof to configure it for operation. The computer program may be supplied from a remote source embodied in a communications medium such as an electronic signal, radio frequency carrier wave or optical carrier wave. Such carrier media are also envisaged as aspects of the present invention.

It will be understood by those skilled in the art that, although the present invention has been described in relation to the above described example embodiments, the invention is not limited thereto and that there are many possible variations and modifications which fall within the scope of the invention.

The scope of the present invention includes any novel features or combination of features disclosed herein. The applicant hereby gives notice that new claims may be formulated to such features or combination of features during prosecution of this application or of any such further applications derived therefrom. In particular, with reference to the appended claims, features from dependent claims may be combined with those of the independent claims and features from respective independent claims may be combined in any appropriate manner and not merely in the specific combinations enumerated in the claims.

Claims

CLAIMS1. A method of operating a wireless telecommunications network, the wireless telecommunications network having a first transceiver and second transceiver, the method comprising the steps of: i) identifying positional information of the first transceiver; H) identifying a first spectral frequency of communications between the first and the second transceivers; Hi) determining, based on the identified positional information, whether a natural environmental feature is present between the first and second transceiver, in which the natural environmental feature is associated with causing at least partial attenuation of wireless communications; iv) identifying, based on the identified first spectral frequency of step fi) and the determination of step Hi), a reconfiguration operation to reconfigure a property of communications to the second transceiver; and v) initiating the reconfiguration operation.
2. A method as claimed in Claim 1, wherein the reconfiguration operation is to reconfigure the second transceiver to communicate at a second spectral frequency, wherein the natural environmental feature has a differential interference effect across the electromagnetic spectrum.
3. A method as claimed in Claim 2, wherein the reconfiguration operation is to transfer the second transceiver from the first transceiver to a third transceiver, wherein communications between the second and third transceiver are at the second spectral frequency.
4. A method as claimed in Claim 2, wherein the reconfiguration operation is to reconfigure the first and second transceiver to communicate at the second spectral frequency.
5. A method as claimed in any one of the preceding claims, further comprising the step of: identifying positional information of the second transceiver, wherein step Hi) is based on the identified positional information of both the first and second transceiver.
6. A method as claimed in any one of the preceding claims, wherein the positional information includes altitude.
7. A method as claimed in any one of the preceding claims, wherein the positional information is only altitude.
8. A method as claimed in any one of Claims 1 to 6, wherein the positional information includes longitude and/or latitude.
9. A method as claimed in any one of the preceding claims, wherein the reconfiguration operation is to change a position of the first and/or second transceiver.
10. A method as claimed in Claim 3, or any of Claims 5 to 9 when dependent on Claim 3, wherein the reconfiguration operation is to change a position of the third transceiver.
11. A method as claimed in any one of the preceding claims, wherein the first transceiver is a base station and the second transceiver is a User Equipment, UE.
12. A method as claimed in Claim 3, any one of Claims 5 to 8 or 10 when dependent on Claim 3, or Claim 9, wherein the third transceiver is a base station.
13. A method as claimed in any one of the preceding claims, wherein the natural environmental feature is an atmospheric source and/or physical source.
14. A method as claimed in any one of the preceding claims, wherein a magnitude of attenuation caused by the natural environmental feature varies over a time period, and the reconfiguration operation is further based on: the time of communications to the second transceiver; and the magnitude of attenuation caused by the natural environmental feature at said time.15. A method as claimed in any one of the preceding claims, further comprising the initial step of: vi) determining whether a previously applied reconfiguration operation improved communications, wherein step iii) and/or step iv) is further based on the determination of step vi).
15. A computer program product comprising instructions which, when executed on a computer, cause the computer to carry out the steps of any one of the preceding claims.
16. A computer-readable storage medium comprising the computer program product as claimed in Claim 15.
17. A network node comprising a processor configured to carry out the steps of any one of Claims 1 to 14.