WO2019137181A1

WO2019137181A1 - Improvements in or relating to mobility scaling in new radio

Info

Publication number: WO2019137181A1
Application number: PCT/CN2018/122597
Authority: WO
Inventors: Benny Assouline; Noam CAYRON
Original assignee: JRD Communication Shenzhen Ltd
Current assignee: JRD Communication Shenzhen Ltd
Priority date: 2018-01-11
Filing date: 2018-12-21
Publication date: 2019-07-18
Anticipated expiration: 2020-07-11
Also published as: GB201800480D0; CN111543077B; CN111543077A; GB2570130A

Abstract

A method and system for enabling a wireless communication device to access services provided by a Radio Access Network, the method comprising: enabling a UE to reselect a cell in a base station between two or more cells, the method comprising defining a mobility state from a plurality of mobility states based on a UE mobility state to thereby reduce an average number of beams (N) required to reselect the cell

Description

Improvements in or relating to mobility scaling in New Radio

Technical Field

Embodiments of the present invention generally relate to wireless communication systems and in particular to devices and methods for enabling a wireless communication device, such as a User Equipment (UE) or any other mobile device to access a Radio Access Technology (RAT) or Radio Access Network (RAN) , particularly but not exclusively to improvements in or relating to mobility scaling in New Radio (NR) .

Background

Wireless communication systems, such as the third-generation (3G) of mobile telephone standards and technology are well known. Such 3G standards and technology have been developed by the Third Generation Partnership Project (3GPP) . The 3 ^rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications. Communication systems and networks have developed towards a broadband and mobile system.

The 3rd Generation Partnership Project has developed the so-called Long Term Evolution (LTE) system, namely, an Evolved Universal Mobile Telecommunication System Territorial Radio Access Network, (E-UTRAN) , as a mobile access network where one or more macro-cells are supported by a base station known as an eNodeB or eNB (evolved NodeB) . More recently, LTE is evolving further towards the so-called 5G or NR (new radio) systems where one or more cells are supported by a base station known as a gNB.

Cell selection or reselection in NR is not yet resolved; however, it has been agreed, as captured in TR 38.804in the NR study phase to reuse the LTE cell reselection principles.

The invention relates to cellular communication, and seeks to address the process relating to an idle UE, regarding which cell to camp on in a cellular network containing multiple beams for each cell.

The following cell reselection methods as specified in TS 36.304 are applicable based on the corresponding parameters broadcast while the UE is camping on a cell in NR:

- Intra-frequency reselection is based on ranking of cells.

- Inter-frequency reselection is based on absolute priorities.

- Inter-RAT reselection can be also based on absolute priorities.

- Frequency specific cell reselection parameters common to all neighboring cells on a frequency;

- Service specific prioritization;

- A concept of neighbor cell lists and black cell lists;

- Speed dependent cell reselection.

In multi-beam operations, measurement quantity of a cell is derived from N best beams corresponding to the same cell where the value of N can be configured to 1 or more than 1.

The use of N beams was decided after identifying only N=1 will cause too many fluctuations and on the other hand that considering all beams may introduce too many low quality beams into the calculations.

For Connected mode in NR there are, however, agreements on cell quality derivation from its beams: Ideally the cell quality should be derived by averaging the best beam with the up to N-1 best beams above absolute configured threshold. Independent N and independent threshold should be configured per carrier frequency in the MeasObject for NR Spectrum Sharing (NR-SS) based and Channel State Information-Reference Signals (CSI-RS) based Layer 3 (L3) mobility. This does not have any implication on the number of CSI-RS resources that can be configured per cell.

The mechanism of measurement aggregation between cell reselections is also a factor and the following is known.

A Radio Resource Control (RRC) _CONNECTED UE shall derive cell measurement results by measuring one or multiple beams associated per cell as configured by the network. For all cell measurement results in RRC_CONNECTED the UE applies the layer 3 filtering as specified below, before using the measured results for evaluation of reporting criteria and measurement reporting. For cell measurements, the network can configure Reference Symbol Received Power (RSRP) , Reference Symbol Received Quality (RSRQ) or Signal to Interference-plus-Noise Ratio (SINR) as trigger quantity. Reporting quantities can be the same as trigger quantity or combinations of quantities (i.e. RSRP and RSRQ; RSRP and SINR; RSRQ and SINR; RSRP, RSRQ and SINR) .

The network may also configure the UE to report measurement information per beam (which can either be measurement results per beam with respective beam identifier (s) or only beam identifier (s) ) . If beam measurement information is configured to be included in measurement reports, the UE applies the layer 3 beam filtering. On the other hand, the exact layer 1 filtering of beam measurements used to derive cell measurement results is implementation dependent.

For layer 3 filtering the UE shall:

1> for each cell measurement quantity and for each beam measurement quantity that the UE performs measurements as described above and according to the details in section 5.5.3.1 of TS 38.331:

2> filter the measured result, before using for evaluation of reporting criteria or for measurement reporting, by the following formula:

F _n= (1-a) ·F _n-1+a·M _n

Where M _n is the latest received measurement result from the physical layer; F _n is the updated filtered measurement result, that is used for evaluation of reporting criteria or for measurement reporting; F _n-1 is the old filtered measurement result, where F ₀ is set to M ₁ when the first measurement result from the physical layer is received; and a = 1/2 ^(k/4) , where k is the filterCoefficient for the corresponding measurement quantity received by the quantityConfig;

3> adapt the filter such that the time characteristics of the filter are preserved at different input rates, observing that the filterCoefficient k assumes a sample rate equal to X ms, where the exact value of X still needs to be determined

As stated before, it has been decided that LTE cell reselection principles are to be reused for NR. In 36.304 the mobility states and scaling are specified.

Various proposals have been made to address the need for mobility scaling and seeking solutions to the outstanding problems. To date none have found a solution which addresses all the issues and enables a system and method of effective mobility scaling in NR. In addition, a number of proposals relating to Cell Quality Derivation in Idle mode in NR have been made. Again these are generally insufficient to address the problems.

A linear power scale based averaging method has been agreed upon, which appears to result in a cell quality that follows the best beam of that cell. For cell reselection, if N＞1 is used, then RRC_IDLE and RRC_INACTIVE UEs should complement the beams detected above the threshold with fictive beams for a cell which has less than N beams above the threshold in the cell quality derivation, so that the same number of beams, with a maximum of N beams, are used in the cell quality derivation for all cells being compared in the cell ranking. It should be noted that complementing to the maximum number of actually detected beams above threshold in a cell would be enough as well, as long as it is smaller than N. The complementing fictive beams should be assigned a fixed quality value. FFS whether the quality value for the complementing fictive beams is set in relation to the absolute threshold (equal to or slightly smaller than the threshold) or in relation to the best beam of the cell, e.g. k x W, where 0 ＜ k ＜ 1 and X is the quality value of the best beam in the cell.

The present invention is seeking to solve at least some of the outstanding problems in this domain.

Summary

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

According to a first aspect of the present invention there is provided a method for enabling a wireless communication device to access services provided by a Radio Access Network, the method comprising: enabling a UE to reselect a cell in a base station between two or more cells, the method comprising defining a mobility state from a plurality of mobility states based on a UE mobility state to thereby reduce an average number of beams (N) required to reselect the cell.

Preferably, a scaling factor is applied to the average number of beams required to select the cell.

Preferably, the scaling factor is applied by means of a mathematical operation comprising at least one of addition and multiplication.

Preferably, the scaling factor is cell specific.

Preferably, the scaling factor is represented by a plurality of predetermined values.

Preferably, the mobility factor is dependent on the number of cell reselections during a time period.

Preferably, the UE shall enter x-mobility state, where x is one of High, Medium, Low, Static, if the criteria for x-mobility state is detected.

Preferably, if criteria for none of the x-mobility states is detected normal mobility state is entered by the UE.

Preferably, if x-mobility state is detected, a speed dependent scaling factor is added on system information.

Preferably, the speed dependent scaling factor is added to the average number of beams.

Preferably, if scaling is applied the UE shall round up the result to a nearest second.

Preferably, the UE does not count consecutive reselections between a same two cells if the same cell is reselected after one other reselection, except if the UE is not static.

Preferably, the Radio Access Network is a New Radio/5G network or any other radio access technology.

According to a second aspect of the present invention there is provided a base station adapted to perform the method of another aspect of the present invention.

According to a third aspect of the present invention there is provided a user equipment adapted to perform the method of another aspect of the present invention.

According to a fourth aspect of the present invention there is provided a non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method of another aspect of the present invention.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory.

Brief description of the drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. Like reference numerals have been included in the respective drawings to ease understanding.

Figure1 is an example of a first use case scenario, according to an embodiment of the present invention.

Figure 2is an example of a second use case scenario, according to an embodiment of the present invention.

Detailed description of the preferred embodiments

Those skilled in the art will recognise and appreciate that the specifics of the examples described are merely illustrative of some embodiments and that the teachings set forth herein are applicable in a variety of alternative settings.

The invention relates to cellular communication, and in particular to the decision process of an idle UE regarding which cell to camp on in a cellular network containing multiple beams for each cell. In the present invention, mobility scaling of cell quality derivation for cell reselection in NR is addressed.

The current general mobility states of a UE in LTE will now be described. Besides Normal-mobility state a High-mobility and a Medium-mobility state are applicable if the parameters (T _CRmax, N _{CR_H}, N _{CR_M} and T _CRmaxHyst) are sent in the system information broadcast of the serving cell.

The state detection criteria are as follows:

Medium-mobility state criteria:

- If number of cell reselections during time period T _CRmax exceeds N _{CR_M} and not exceeds N _{CR_H}

High-mobility state criteria:

- If number of cell reselections during time period T _CRmax exceeds N _{CR_H}

The UE shall not count consecutive reselections between same two cells into mobility state detection criteria if same cell is reselected just after one other reselection.

The state transitions include the following:

The UE shall:

- if the criteria for High-mobility state is detected:

о enter High-mobility state.

- else if the criteria for Medium-mobility state is detected:

о enter Medium-mobility state.

- else if criteria for either Medium-or High-mobility state is not detected during time period T _CRmaxHyst:

о enter Normal-mobility state.

If the UE is in High-or Medium-mobility state, the UE shall apply the speed dependent scaling rules.

The UE shall apply the following scaling rules:

- If neither Medium-nor Highmobility state is detected:

о no scaling is applied.

- If High-mobility state is detected:

о Add the sf-High of "Speed dependent ScalingFactor for Q _hyst” to Q _hyst if sent on system information

- For E-UTRAN cells multiply Treselection _EUTRA by the sf-High of "Speed dependent ScalingFactor for Treselection _EUTRA” if sent on system information

The same goes for other RAT.

- If Medium-mobility state is detected:

о Add the sf-Medium of "Speed dependent ScalingFactor for Q _hyst for medium mobility state" to Q _hyst if sent on system information

- For E-UTRAN cells multiply Treselection _EUTRA by the sf-Medium of "Speed dependent ScalingFactor for Treselection _EUTRA" if sent on system information

The same goes for other RAT.

In case scaling is applied to any Treselection _RAT parameter the UE shall round up the result after all scaling to the nearest second. This implies that cell reselection cannot happen more frequently than once a second.

Mobility Scaling in RRC_Connected mode in NR requires use of MeasConfig. The IE MeasConfig specifies measurements to be performed by the UE, and covers intra-frequency, inter-frequency and inter-RAT mobility as well as configuration of measurement gaps.

Idle mode mobility will follow the RRC_Connected mode.

Cell Quality Derivation Mobility Scaling in Idle mode in NR will also take into consideration, for example mobility states, speed dependent scaling, forward compatibility for CSG, cell reservations, etc.

In a cellular network relying on a technology such as LTE or NR, an idle mode UE, after a quick first cell selection, has to choose the cell which provides it with the best conditions of all the cells it is allowed to camp on. This is called Cell Reselection and is based on criteria which involve measurements of the camped and neighboring cells. Some of the parameters used in the cell reselection procedures are mobility dependent. Measurements are taken into account over a period of time and each cell is then ranked according to the measurements and the highest ranked cell is chosen for reselection.

In LTE, an Idle UE has several mobility states, which are based on counting cell reselections, and are applicable if the appropriate parameters are sent in the system information broadcast of the camped cell. When a UE meets the criteria for a mobility state, it has to apply the appropriate scaling rules to the parameters of cell reselection. Cell reselection cannot happen more frequently than once a second, in order to prevent a frequent "ping-pong" between cells.

The basic cell reselection criteria in NR are comparable to those of LTE, but since multiple beams are generally being used, the cell quality is derived amongst the beams corresponding to the same cell. This is currently done by averaging each cell′s N best beams. However, this number is currently set per carrier frequency, and does not take into account the mobility of the UE. This may cause a suboptimal cell reselection.

It is therefore proposed to scale N according to UE mobility, in order to optimize cell reselection. Further, it is also proposed to also add at least a Static or Low mobility state, allowing also for a scaling down process.

The need for mobility based scaling for cell reselection is largely undisputed. However, the use of beams adds a level of complexity to the issue and is one of the problems addressed in the present invention.

The present invention looks at a number of use case scenarios, two of which are shown in figures 1 and 2.

In figure 1, a static UE that has to choose with N=3 between a cell with 3 mediocre beams (on the right) and a cell with one really good beam and two on-threshold beams (on the left) , whose average is lower than the mediocre beams. Here N=1 would be much more appropriate, helping to choose the cell with the best beam of all.

In figure 2, a moving UE that has to choose with N=1 between a cell with one good beam (on the left) and a cell with 3 mediocre beams (on the right) . Here it is likely that choosing the cell with more coverage would be wiser, which would be given by N=3.

While N is not expected to be cell specific, making the scaling factors cell specific and parametrized could give the network maximum flexibility, coupled with a low complexity. To minimize complexity and signalling, the scaling factors can also have a default value.

Another reason for making the scaling factors parametrized is the kind of recurrence relation used for measurements. In cases where the flexibility of the measurements change is not high enough to compensate for "losing" beams, lowering N as mobility rises may prove to be beneficial in some cases.

The present invention seeks to address some of the problems in this domain by defining a new mobility state. To maximize the advantage of the present invention, additional mobility states are defined to add a Static and/or a Low mobility states, where Low can be used to decrease N, while Static would be used to set N=1.

Scaling of N with mobility is then carried out. New scaling factors, Integers sf-Nmobility (Nhigh, Nnormal etc. ) where sf-Nmobility ≥ 1-N, are introduced, which will, in one embodiment, be added to N according to the UE mobility states, as decided for NR.

In an alternative embodiment, this could be achieved with a multiplicative sfs ＞ 0 by rounding up to the closest integer.

The additive sfs of the first embodiment, are simpler as all the relevant numbers are integers. To calculate the appropriate multiplicative sf for the target N, addition would also have to be used.

Setting the scaling factors as parameters allows for maximum flexibility for different beam maps scenarios, while keeping simplicity and being in line with the standards.

Although it has not yet been decided whether N will be cell specific, in the present invention sf-Nmobility can be cell specific or not, with no relation to the decision for N. This would allow again for greater flexibility with accordance to cell beam pattern while also keeping simplicity of a general N per carrier frequency for all Normal mobility UEs or all of UEs if the scaling parameters are not sent.

Alternatively, instead of using parameters, predetermined values can be used, for example:

· sf-Nhigh = max (0, all beams above threshold-N)

· sf-Nmedium = max (0, floor ( (all beams above threshold-N) /2) )

· sf-Nnormal = 0

· sf-Nlow = -floor (N/2)

· sf-Nstatic= 1-N

This approach has the advantage of not needing to send additional parameters on broadcast system information, but may reduce some of the flexibility of the alternative embodiments. These values can be used as default values and other examples may be used as required.

Optional consolidation of the two proposals may be considered as appropriate.

Even though the above embodiments are independent from the actual way of deciding mobility and from the actual values the sfs could take, especially if cell-specific, an example of these proposals in specifications may be given, assuming LTE baseline is maintained.

In accordance with the present invention, mobility states of the UE may operate as follows.

Besides Normal-mobility state, additional mobility states, High-, Medium-, Low-, Static-mobility states are applicable if the parameters (TCRmax, N _{CR_H}, N _{CR_M}, N _{CR_L}, T _CRmaxHyst, N) are sent in the system information broadcast of the serving cell. NCR_X in this case relates to thresholds for number of reselections and not directly with N, the number of beams to be averaged.

State detection criteria are as follows:

Static-mobility state criteria:

- If number of cell reselections during time period T _CRmax is 0

о Low-mobility state criteria:

- If number of cell reselections during time period T _CRmax exceeds 0 but does not exceed NCR_L

о Medium-mobility state criteria:

о High-mobility state criteria:

- If number of cell reselections during time period T _CRmax exceeds N _{CR_H}

о The UE shall not count consecutive reselections between same two cells into mobility state detection criteria if the same cell is reselected just after one other reselection, except if the number of reselections is currently 0 (the UE is not static)

State transitions:

The UE shall, if the criteria for x-mobility state is detected, enter x-mobility state, where x is one of High, Medium, Low, Static.

Else, if criteria for none of the above mobility state is detected during time period T _CRmaxHyst:

- enter Normal-mobility state.

If the UE is in other than Normal-mobility state, it shall apply the speed dependent scaling rules.

UE shall apply the following scaling rules:

· -If Normal-mobility state is detected:

о no scaling is applied.

· If x-mobility state is detected, where x is one of High, Medium, Low, Static:

о Add the sf-x of "Speed dependent ScalingFactor for Q _hyst” to Q _hyst if sent on system information

о Add the sf-Nx parameter to N if sent on system information or if default values exist

· For E-UTRAN cells multiply Treselection _EUTRA by the sf-x of "Speed dependent ScalingFactor for Treselection _EUTRA” if sent on system information

The same goes for other RAT

In case scaling is applied to any Treselection _RAT parameter the UE shall round up the result after all scaling to the nearest second.

The meaning of parameters such as Qhyst are known but are not essential to the understanding of the present invention. Qhyst: is a hysteresis value preventing too-frequent reselection back and forth between cells of nearly equal rank and is relevant to scaling rules.

The present invention has this been described with respect to mobility scaling in cell reselection in NR. It may apply equally to other similar scenarios, such as for example if beam-like behaviour is introduced to any other environment.

Although not shown in detail any of the devices or apparatus that form part of the network may include at least a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method of any aspect of the present invention. Further options and choices are described below.

The signal processing functionality of the embodiments of the invention especially the gNB and the UE may be achieved using computing systems or architectures known to those who are skilled in the relevant art. Computing systems such as, a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc. ) , mainframe, server, client, or any other type of special or general purpose computing device as may be desirable or appropriate for a given application or environment can be used. The computing system can include one or more processors which can be implemented using a general or special-purpose processing engine such as, for example, a microprocessor, microcontroller or other control module.

The computing system can also include a main memory, such as random access memory (RAM) or other dynamic memory, for storing information and instructions to be executed by a processor. Such a main memory also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor. The computing system may likewise include a read only memory (ROM) or other static storage device for storing static information and instructions for a processor.

The computing system may also include an information storage system which may include, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disc (CD) or digital video drive (DVD) read or write drive (R or RW) , or other removable or fixed media drive. Storage media may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drive. The storage media may include a computer-readable storage medium having particular computer software or data stored therein.

In alternative embodiments, an information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components may include, for example, a removable storage unit and an interface , such as a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to computing system.

The computing system can also include a communications interface. Such a communications interface can be used to allow software and data to be transferred between a computing system and external devices. Examples of communications interfaces can include a modem, a network interface (such as an Ethernet or other NIC card) , a communications port (such as for example, a universal serial bus (USB) port) , a PCMCIA slot and card, etc. Software and data transferred via a communications interface are in the form of signals which can be electronic, electromagnetic, and optical or other signals capable of being received by a communications interface medium.

In this document, the terms ‘computer program product’ , ‘computer-readable medium’ and the like may be used generally to refer to tangible media such as, for example, a memory, storage device, or storage unit. These and other forms of computer-readable media may store one or more instructions for use by the processor comprising the computer system to cause the processor to perform specified operations. Such instructions, generally referred to as ‘computer program code’ (which may be grouped in the form of computer programs or other groupings) , when executed, enable the computing system to perform functions of embodiments of the present invention. Note that the code may directly cause a processor to perform specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, a Programmable Read Only Memory, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory and a Flash memory

In an embodiment where the elements are implemented using software, the software may be stored in a computer-readable medium and loaded into computing system using, for example, removable storage drive. A control module (in this example, software instructions or executable computer program code) , when executed by the processor in the computer system, causes a processor to perform the functions of the invention as described herein.

Furthermore, the inventive concept can be applied to any circuit for performing signal processing functionality within a network element. It is further envisaged that, for example, a semiconductor manufacturer may employ the inventive concept in a design of a stand-alone device, such as a microcontroller of a digital signal processor (DSP) , or application-specific integrated circuit (ASIC) and/or any other sub-system element.

It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to a single processing logic. However, the inventive concept may equally be implemented by way of a plurality of different functional units and processors to provide the signal processing functionality. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organisation.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may optionally be implemented, at least partly, as computer software running on one or more data processors and/or digital signal processors or configurable module components such as FPGA devices. Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein.

Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognize that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Also, the inclusion of a feature in one category of claims does not imply a limitation to this category, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. In addition, singular references do not exclude a plurality. Thus, references to ‘a’ , ‘an’ , ‘first’ , ‘second’ , etc. do not preclude a plurality.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term ‘comprising’ or “including” does not exclude the presence of other elements.

Claims

A method for enabling a wireless communication device to access services provided by a Radio Access Network, the method comprising: enabling a UE to reselect a cell between two or more cells, the method comprising defining a mobility state from a plurality of mobility states based on a UE mobility state to thereby reduce an average number of beams (N) required to reselect the cell.
The method of claim 1, wherein a scaling factor is applied to the average number of beams required to select the cell.
The method of claim 2, wherein the scaling factor is applied by means of a mathematical operation comprising at least one of addition and multiplication.
The method of claim 2 or claims 3, wherein the scaling factor is cell specific.
The method of any of claim 2 to 4, wherein the scaling factor is represented by a plurality of predetermined values.
The method of any preceding claims, wherein the mobility factor is dependent on the number of cell reselections during a time period.
The method of claim 6, wherein the UE shall enter x-mobility state, where x is one of High, Medium, Low, Static, if the criteria for x-mobility state is detected.
The method of claim 7, wherein if criteria for none of the x-mobility states is detected normal mobility state is entered by the UE.
The method of claim 6 or claim 7, wherein if x-mobility state is detected, a speed dependent scaling factor is added on system information.
The method of claim 9, wherein the speed dependant scaling factor is added to the average number of beams.
The method of any of claims 6 to 10, wherein if scaling is applied the UE shall round up the result to a nearest second.
The method of any of claims 6 to 11, wherein the UE does not count consecutive reselections between a same two cells if the same cell is reselected after one other reselection, except if the UE is not static.
The method of any one of the preceding claim wherein the Radio Access Network is a New Radio/5G network or any other radio access technology network.
A user equipment, UE, apparatus comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method as claimed in any one of claims 1-13.
A base station, BS, apparatus comprising a processor, a storage unit and a communications interface, wherein the processor unit, storage unit, and communications interface are configured to perform the method as claimed in any one of claims 1-13
A non-transitory computer readable medium having computer readable instructions stored thereon for execution by a processor to perform the method according toany of claims 1-13.