Slice-aware cell selection and random access techniques

Abstract

To provide slice-recognition cell selection and random access techniques.SOLUTION: Techniques are described in relation to implementing slice-recognition cell selection or slice-recognition random access techniques. An exemplary wireless communication method includes implementing, by a communication device, a cell selection technique using one set of cell selection-related information associated with a slice. The one set of cell selection-related information is from a plurality of sets of cell selection-related information related to a plurality of slices, and each set of cell selection-related information is associated with one slice from the plurality of slices.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] TECHNICAL FIELD This disclosure is directed generally to digital wireless communications. [Background technology]

[0002] Mobile telecommunications technologies are moving the world towards an increasingly connected and networked society. Compared to existing wireless networks, next generation systems and wireless communication techniques will need to support a much broader range of use case characteristics and provide a more complex and advanced range of access requirements and flexibility.

[0003] Long Term Evolution (LTE) is a standard for wireless communications for mobile devices and data terminals developed by the 3rd Generation Partnership Project (3GPP®). LTE Advanced (LTE-A) is a wireless communications standard that extends the LTE standard. The fifth generation of wireless systems, known as 5G, is committed to evolving the LTE and LTE-A wireless standards to support higher data rates, multiple connections, ultra-low latency, high reliability, and other emerging business needs. Summary of the Invention [Means for solving the problem]

[0004] Techniques are disclosed for slice-aware cell selection (or cell reselection) and / or random access techniques.

[0005] A first example wireless communication method includes performing, by a communications device, a cell selection technique using a set of cell selection-related information associated with a slice, the set of cell selection-related information being from a plurality of sets of cell selection-related information associated with a plurality of slices, each set of cell selection-related information being associated with a slice from the plurality of slices.

[0006] In some embodiments, the communications device selects or determines a set of cell selection related information associated with a slice from a plurality of sets of cell selection related information related to the plurality of slices, and performs a cell selection technique using the set of cell selection related information associated with the slice, each set of cell selection related information being associated with one slice from the plurality of slices.

[0007] In some embodiments, the multiple sets of cell selection related information include supported slice information for each slice from the multiple slices, where for each slice of the multiple slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. In some embodiments, the multiple sets of cell selection related information include cell selection priority information for each slice from the multiple slices, where for each slice of the multiple slices, the cell selection priority information indicates a cell selection priority value for the slice, where the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. In some embodiments, the multiple sets of cell selection related information include redirection target information for each slice from the multiple slices, where for each slice of the multiple slices, the redirection target information indicates a frequency to use for a cell selection technique for the slice. In some embodiments, the communications device performs a cell selection technique with a cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, where the cell selection priority value is associated with a slice that is first in order in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI.

[0008] In some embodiments, the communications device performs a cell selection technique with the cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, the cell selection priority value being associated with any one of a slice group, an access category, and an access category group associated with a slice that is first in order in a list of slices in an authorized single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. In some embodiments, the communications device performs a cell selection technique with the cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, the slice that is first in order associated with the cell selection priority value in a list of slices in an authorized single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. In some embodiments, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency being associated with the cell, the frequency having the highest priority in response to the frequency being associated with a maximum number of supported slices from an allowed single network slice selection assistance information (S-NSSAI) (or from a requested S-NSSAI).

[0009] In some embodiments, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency associated with the cell, the frequency having the highest priority in response to the frequency being supported by a slice that is first in order in a list of slices in an authorized single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. In some embodiments, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency associated with the cell, the frequency having the highest priority in response to the frequency being supported by any one of a slice group, an access category, and an access category group that is first in order in a list of slices in an authorized single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI.

[0010] A second example wireless communication method includes, by a communication device, implementing a random access technique using a set of random access channel (RACH) configurations associated with a slice, the set of RACH configurations being from a plurality of sets of RACH configurations associated with a plurality of slices, and each set from the plurality of sets of RACH configurations being associated with a slice from the plurality of slices.

[0011] In some embodiments, the communications device selects or determines a set of RACH configurations for a slice from a plurality of sets of RACH configurations associated with the plurality of slices, each set of RACH configurations being associated with a slice from the plurality of slices, and performs the random access technique using the set of RACH configurations associated with the slice.

[0012] In some embodiments, the multiple sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice for the multiple slices, the resources including locations of RACH occasions in the frequency domain and the time domain, the resources being common resources associated with the multiple communication nodes or dedicated resources assigned to the communication nodes. In some embodiments, the multiple sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the multiple slices. In some embodiments, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices and a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices.

[0013] In some embodiments, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments, the communication device performs the random access technique by performing a two-step random access technique or by performing a four-step random access technique. In some embodiments, the communication device performs the two-step random access technique or the four-step random access technique by using common resources associated with the multiple communication nodes in response to the communication device determining that the random access technique performed using one set of RACH configurations associated with the slice has resulted in a certain number of failed results. In some embodiments, the communication device performs the four-step random access technique by using another set of RACH configurations associated with the slice or by using common resources associated with the multiple communication nodes in response to the communication device determining that the two-step random access technique performed using one set of RACH configurations associated with the slice has resulted in a certain number of failed results.

[0014] In some embodiments, the communications device implements the random access technique by using a first set of RACH prioritization parameters configured for a communications device configured for Multimedia Priority Services (MPS) or Mission Critical Services (MCS), or the communications device implements the random access technique by using a second set of RACH prioritization parameters configured for a slice.

[0015] A third example wireless communication method includes transmitting, by a network device, multiple sets of cell selection-related information related to multiple slices, each set of cell selection-related information being associated with a slice from the multiple slices.

[0016] In some embodiments, the multiple sets of cell selection related information include supported slice information for each slice from the multiple slices, where for each slice of the multiple slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. In some embodiments, the multiple sets of cell selection related information include cell selection priority information for each slice from the multiple slices, where for each slice of the multiple slices, the cell selection priority information indicates a cell selection priority value for the slice, where the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. In some embodiments, the multiple sets of cell selection related information include redirection target information for each slice from the multiple slices, where for each slice of the multiple slices, the redirection target information indicates a frequency to use for a cell selection technique for the slice.

[0017] In some embodiments, the sets of cell selection related information are transmitted to the communication devices comprising the communication device via system information, hi some embodiments, the sets of cell selection related information are transmitted via communication device dedicated Radio Resource Control (RRC) signaling.

[0018] A fourth example wireless communication method includes performing, by a network device, a first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with a plurality of slices, each set from the plurality of sets of RACH configurations being associated with one slice from the plurality of slices, and receiving, by the network device, a random access preamble from a communication device using one set of RACH configurations associated with the slice from the plurality of sets of RACH configurations.

[0019] In some embodiments, the method further includes performing, by the network device, a second transmission comprising a message to the communication device, the message comprising an identifier of a set of RACH configurations associated with a slice to be used by the communication device, and the random access preamble is received in response to the second transmission of the message. In some embodiments, the message is included in a paging message or a paging downlink control information (DCI) or a short message. In some embodiments, the multiple sets of RACH configurations include resources for performing a two-step random access technique or a four-step random access technique for each slice for the multiple slices, the resources including locations of RACH occasions in the frequency domain and the time domain, and the resources being common resources associated with the multiple communication nodes or dedicated resources assigned to the communication nodes. In some embodiments, the multiple sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the multiple slices.

[0020] In some embodiments, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices and a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments, the first transmission comprising the multiple sets of RACH configurations is performed via system information to the multiple communication devices comprising the communication device. In some embodiments, the first transmission comprising the multiple sets of RACH configurations is performed via radio resource control (RRC) signaling dedicated to the communication device.

[0021] In yet another exemplary aspect, the methods described above are embodied in the form of processor executable code and stored in a non-transitory computer readable storage medium, the code contained in the computer readable storage medium, when executed by a processor, causing the processor to implement the methods described in this patent document.

[0022] In yet another exemplary embodiment, a device configured (or operable) to perform the methods described above is disclosed.

[0023] These and other aspects and their implementations are described in detail in the drawings, description, and claims. The present invention provides, for example, the following: (Item 1) 1. A wireless communication method, the method comprising: performing, by the communications device, a cell selection technique using a set of cell selection related information associated with the slice; the set of cell selection related information is from a plurality of sets of cell selection related information associated with a plurality of slices; 11. A method of wireless communication, wherein each set of cell selection related information is associated with a slice from the plurality of slices. (Item 2) the plurality of sets of cell selection related information include supported slice information for each slice from the plurality of slices; 2. The method of claim 1, wherein for each slice of the plurality of slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. (Item 3) the plurality of sets of cell selection related information include cell selection priority information for each slice from the plurality of slices; for each slice of the plurality of slices, the cell selection priority information indicates a cell selection priority value for the slice; 2. The method of claim 1, wherein the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. (Item 4) the plurality of sets of cell selection related information include redirection target information for each slice from the plurality of slices; 2. The method of claim 1, wherein for each slice of the plurality of slices, the redirection target information indicates a frequency to be used for the cell selection technique for the slice. (Item 5) The communications device performs the cell selection technique with a cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell; The method according to item 1, wherein the cell selection priority value is associated with a slice that is first in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. (Item 6) The communications device performs the cell selection technique with a cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell; The method of item 1, wherein the cell selection priority value is associated with any one of a slice group, an access category, and an access category group associated with a slice that is first in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. (Item 7) The communications device performs the cell selection technique with a cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell; the slices are associated with the cell selection priority values; The method according to item 1, wherein the slice is the first one in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI in an order associated with the cell selection priority value. (Item 8) The communication device performs the cell selection technique with a cell by using a frequency having a highest priority; the frequency is associated with the cell; 2. The method of claim 1, wherein the frequency has the highest priority in response to the frequency being associated with a maximum number of supported slices from an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. (Item 9) The communication device performs the cell selection technique with a cell by using a frequency having a highest priority; the frequency is associated with the cell; Item 2. The method of item 1, wherein the frequency has the highest priority in response to the frequency being supported by a slice that is first in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. (Item 10) The communication device performs the cell selection technique with a cell by using a frequency having a highest priority; the frequency is associated with the cell; Item 2. The method of item 1, wherein the frequency has the highest priority in response to being supported by any one of a slice group, an access category, and an access category group associated with a slice that is first in order in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI. (Item 11) 1. A wireless communication method, the method comprising: implementing, by the communication device, a random access technique using a set of random access channel (RACH) configurations associated with the slice; the set of RACH configurations is from a plurality of sets of RACH configurations associated with a plurality of slices; 11. A wireless communication method, wherein each set from the plurality of sets of RACH configurations is associated with one slice from the plurality of slices. (Item 12) the sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice for the plurality of slices; the resources include locations of RACH occasions in the frequency domain and the time domain; 12. The method of claim 11, wherein the resource is a common resource associated with a plurality of communication nodes or a dedicated resource assigned to the communication node. (Item 13) 12. The method of claim 11, wherein the sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of a plurality of slices. (Item 14) Item 12. The method of item 11, wherein the plurality of sets of RACH configurations includes a first value indicating a maximum number of failed random access attempts allowed for each slice from the plurality of slices, and a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. (Item 15) Item 12. The method of item 11, wherein the plurality of sets of RACH configurations includes a first value indicating a maximum number of failed random access attempts allowed for each slice from the plurality of slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. (Item 16) Item 12. The method of item 11, wherein the communication device implements the random access technique by implementing a two-step random access technique or by implementing a four-step random access technique. (Item 17) Item 12. The method of item 11, wherein the communications device performs a two-step random access technique or a four-step random access technique by using common resources associated with a plurality of communications nodes in response to the communications device determining that the random access technique performed using one set of the RACH configurations associated with the slice resulted in a certain number of failed results. (Item 18) Item 12. The method of item 11, wherein in response to the communications device determining that a two-step random access technique implemented using one set of the RACH configurations associated with the slice has resulted in a certain number of failed results, the communications device implements a four-step random access technique by using another set of RACH configurations associated with the slice or by using common resources associated with multiple communications nodes. (Item 19) The communication device implements the random access technique by using a first set of RACH prioritization parameters configured for the communication device configured for Multimedia Priority Services (MPS) or Mission Critical Services (MCS); or Item 12. The method of item 11, wherein the communications device implements the random access technique by using a second set of RACH prioritization parameters configured for a slice. (Item 20) 1. A wireless communication method, the method comprising: transmitting, by the network device, a plurality of sets of cell selection related information associated with a plurality of slices; 11. A method of wireless communication, wherein each set of cell selection related information is associated with a slice from the plurality of slices. (Item 21) the plurality of sets of cell selection related information include supported slice information for each slice from the plurality of slices; 21. The method of claim 20, wherein for each slice of the plurality of slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. (Item 22) the plurality of sets of cell selection related information include cell selection priority information for each slice from the plurality of slices; for each slice of the plurality of slices, the cell selection priority information indicates a cell selection priority value for the slice; 21. The method of claim 20, wherein the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. (Item 23) the plurality of sets of cell selection related information include redirection target information for each slice from the plurality of slices; 21. The method of claim 20, wherein for each slice of the plurality of slices, the redirection target information indicates a frequency to be used for the cell selection technique for the slice. (Item 24) 24. A method according to any of items 20-23, wherein the sets of cell selection related information are transmitted via system information to a plurality of communication devices comprising the communication device. (Item 25) 24. A method according to any of items 20-23, wherein the sets of cell selection related information are transmitted via Radio Resource Control (RRC) signaling dedicated to the communication device. (Item 26) 1. A wireless communication method, the method comprising: performing, by the network device, a first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with a plurality of slices, each set from the plurality of sets of RACH configurations being associated with one slice from the plurality of slices; receiving, by the network device, a random access preamble from a communication device using a set of RACH configurations associated with a slice from the plurality of sets of RACH configurations; A wireless communication method comprising: (Item 27) performing, by the network device, a second transmission comprising the message to the communication device; the message comprises a set of identifiers of the RACH configurations associated with the slice to be used by the communications device; 27. The method of claim 26, wherein the random access preamble is received in response to the second transmission of the message. (Item 28) 28. The method according to claim 27, wherein the message is included in a paging message or a paging downlink control information (DCI) or a short message. (Item 29) the sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice for the plurality of slices; the resources include locations of RACH occasions in the frequency domain and the time domain; 27. The method of claim 26, wherein the resource is a common resource associated with a plurality of communication nodes or a dedicated resource assigned to the communication node. (Item 30) 27. The method of claim 26, wherein the sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of a plurality of slices. (Item 31) 27. The method of claim 26, wherein the plurality of sets of RACH configurations includes a first value indicating a maximum number of failed random access attempts allowed for each slice from the plurality of slices, and a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. (Item 32) 27. The method of claim 26, wherein the plurality of sets of RACH configurations includes a first value indicating a maximum number of failed random access attempts allowed for each slice from the plurality of slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. (Item 33) 33. The method according to any of claims 26-32, wherein the first transmission comprising a plurality of sets of RACH configurations is performed via system information to a plurality of communication devices comprising the communication device. (Item 34) 33. The method of any of items 26-32, wherein the first transmission comprising the plurality of sets of RACH configurations is performed via Radio Resource Control (RRC) signaling dedicated to the communication device. (Item 35) 35. An apparatus for wireless communication comprising a processor configured to implement the methods according to one or more of items 1-34. (Item 36) A non-transitory computer readable program storage medium storing code that, when executed by a processor, causes the processor to implement a method according to one or more of items 1-34. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 shows an example flow chart for performing cell (re)selection and / or random access procedures.

[0025] [Diagram 2] FIG. 2 shows an example flow chart of a method for implementing a slice-aware cell selection technique.

[0026] [Diagram 3] FIG. 3 illustrates an example flow chart of a method for implementing a slice-aware random access technique.

[0027] [Figure 4A] FIG. 4A shows a flowchart of a method for a network device to provide multiple sets of cell selection related information for multiple slices for a communications device to implement a slice-aware cell selection technique.

[0028] [Figure 4B] FIG. 4B shows a flowchart of a method for a network device to provide multiple sets of RACH configurations for multiple slices for a communication device to implement a slice-aware random access technique.

[0029] [Diagram 5] FIG. 5 shows an example block diagram of a hardware platform that may be part of a network node or user equipment.

[0030] [Figure 6] FIG. 6 illustrates an example of wireless communication involving a base station (BS) and user equipment (UE) according to some implementations of the disclosed technology. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Network slicing is introduced in New Radio (NR), which is a concept to enable differentiated treatment depending on each customer requirement. With slicing, a Mobile Network Operator (MNO) can consider its customers as belonging to different tenant types, each of which has different service requirements that each tenant determines in terms of the slice types that it is eligible to use based on its service level agreement (SLA) and subscription.

[0032] To support slice-aware cell (re)selection and access, different cell (re)selection priorities, redirection targets, RACH resources in frequency and time domains, random access preambles, and RACH prioritization parameters may be provided for different slices, but the user equipment (UE) behavior in selecting and using these configurations during cell (re)selection and random access procedures is not clear.

[0033] FIG. 1 shows an example flowchart for performing a cell (re)selection and / or random access procedure. Operation 102 includes a UE (or a communication device) receiving cell (re)selection information and / or a RACH configuration per slice. Operation 104 includes the UE applying the cell (re)selection information or the RACH configuration during the cell (re)selection or random access procedure, respectively. In some embodiments, the UE receives the cell (re)selection information and / or the RACH configuration per slice / slice group / access category / access category group / UE type / service type, and the UE applies the cell (re)selection information and / or the RACH configuration during the cell (re)selection and / or random access procedure for a slice / slice group / access category / access category group / UE type / service type. In this patent document, the term "cell (re)selection" can include cell selection or cell reselection, and the term "cell" can include a base station or a network node.

[0034] Example Item 1: In operation 102 of FIG. 1, the cell (re)selection information per slice may include any one or more of the following: Supported slice information and / or reselection priority per slice / supported slice group information and / or reselection priority per slice group / supported access category information and / or reselection priority per access category / supported access category group information and / or reselection priority per access category group / supported UE type information and / or reselection priority per UE type / supported service types and / or reselection priority per service type for intra-frequency / inter-frequency / inter-RAT cells. Such information can be provided via SIB2 / 3 / 4 / 5 or newly introduced SIBs. The corresponding SIBs can be configured as on-demand SIBs. The full set or segmentation of cell (re)selection information per slice / slice group / access category / access category group / UE type / service type can be provided in the SIBs. Supported slice / slice group / access category / access category group / UE type / service type information and / or reselection priority information per slice / slice group / access category / access category group / UE type / service type that may be provided by the SIB may be broadcast to one or more UEs within the transmission range of the cell. Supported slices / slice groups / access categories / access category groups / UE types / service type information in the RRCRelease message, and / or dedicated reselection priority per slice / dedicated reselection priority per slice group / dedicated reselection priority per access category / dedicated reselection priority per access category group / dedicated reselection priority per UE type / dedicated reselection priority per service type. Supported slices / slice groups / access categories / access category groups / UE types / service type information, and / or reselection priority information per slice / slice group / access category / access category group / UE type / service type can be indicated to a particular UE via the RRCRelease message. A timer can be configured in the RRCRelease message, the timer indicating the amount of time when the supported slices / slice groups / access categories / access category groups / UE types / service type information, and / or reselection priority information per slice / slice group / access category / access category group / UE type / service type is valid. For example, if the UE determines that the timer received in the RRCRelease message has not expired, the UE may use the supported slice / slice group / access category / access category group / UE type / service type information and / or reselection priority information per slice / slice group / access category / access category group / UE type / service type as described in this patent document to perform cell (re)selection or RACH. In another example, if the UE determines that the timer received in the RRCRelease message has expired, the UE may use the supported slice / slice group / access category / access category group / UE type / service type information and / or reselection priority information per slice / slice group / access category / access category group / UE type / service type that may be broadcast to one or more UEs via a SIB. Redirection target information per slice / slice group / access category / access category group / UE type / service type can be indicated in the RRCRelease message. For each of the slices, the redirection target information can indicate a frequency target for cell (re)selection for the slice / slice group / access category / access category group / UE type / service type. A timer can be configured in the RRCRelease message, the timer indicating the amount of time when the redirection target information per slice / slice group / access category / access category group / UE type / service type is valid. For example, if the UE determines that the timer received in the RRCRelease message has not expired, the UE can use the redirection target information per slice / slice group / access category / access category group / UE type / service type as described in this patent document to perform cell (re)selection or RACH. In another example, if the UE determines that the timer received in the RRCRelease message has expired, the UE may use supported slice / slice group / access category / access category group / UE type / service type information and reselection priority information per slice / slice group / access category / access category group / UE type / service type that may be broadcast to one or more UEs via SIB.

[0035] The supported slice information in the SIB or RRCRelease message can be expressed as S-NSSAI / SST / part of S-NSSAI / slice association access category / slice index / slice group index.

[0036] Different cell (re)selection information per slice / slice group / access category / access category group / UE type / service type can be provided for different PLMNs sharing the same cell. Common cell (re)selection information per slice / slice group / access category / access category group / UE type / service type may be provided for a cell and be applicable to all PLMNs sharing the same cell.

[0037] Exemplary Item 2: In operation 104 of FIG. 1, the UE applying the cell (re)selection information for each slice during the cell (re)selection procedure may include the UE performing any of the following operations in exemplary items 2.1-2.5:

[0038] Example Item 2.1: Use of reselection priority per slice / slice group / access category / access category / slice group / access category / access category group / UE type / service type group in system information The UE applies a reselection priority corresponding to (or associated with) the first slice in the allowed / requested S-NSSAI, if configured, or a reselection priority corresponding to the slice group / access category / access category group to which the first slice belongs. If no reselection priority is configured for the first slice / slice group / access category / access category group, the UE applies a common priority. In some embodiments, the common priority comprises a default priority that is applicable to one or more (or all) slices. · Example: As shown in Table 1 below, the UE may select and apply a reselection priority for slice number 1 (indicated in bold italic text) since the UE determines that at least slice number 1 is the first slice. [Table 1] ·The UE applies the reselection priority corresponding to the first slice / slice group / access category / access category group for which per-slice reselection priority is configured. Example: As shown in Table 2 below, the UE may select and apply reselection priority for slice number 2 (indicated in bold italic text) because the UE determines that at least slice number 2 is the first slice for which reselection priority is provided. [Table 2]

[0039] Example Item 2.2: Use of Supported Slice Information in System Information (for the Case When No Specific Priority is Configured for Any Slice) · The UE considers (or determines) that the frequency with the highest number of supported slices overlapping with the granted / requested S-NSSAI is associated (or has) the highest priority. Example: As shown in Table 3 below, the UE may determine that frequency F3 (shown in bold italic text) is associated with the highest priority because the UE determines that at least F3 has the maximum number of supported slices that overlap with the allowed / requested S-NSSAI. [Table 3] · The UE shall consider (or decide) that the frequency supporting the first slice in the allowed / requested S-NSSAI or the slice group / access category / access category group to which the first slice belongs is associated with the highest priority. Example: As shown in Table 4 below, the UE may determine that frequency F2 (shown in bold italic text) is associated with the highest priority because the UE determines that at least F2 supports the first slice in the allowed / requested S-NSSAI. [Table 4] If more than one frequency supports the first slice in the allowed / requested S-NSSAI, the UE may determine that the frequency configured with a higher reselection priority (e.g., common reselection priority) will be associated with the highest priority. Example: As shown in Table 5 below, the UE may determine that at least both F2 and F3 support the first slice, but frequency F3 (shown in bold italic text) will be considered the highest priority because the UE determines that the common reselection priority configured for F3 is higher than that of F2. [Table 5]

[0040] Example Item 2.3: Use of Dedicated Reselection Priority Per Slice in RRCRelease Messages The UE shall apply a dedicated reselection priority corresponding to the first slice in the allowed / requested S-NSSAI, if configured. If no reselection priority is configured for the first slice, the UE shall apply a common dedicated priority. Example: As shown in Table 6 below, the UE applies a dedicated reselection priority for slice number 1 (indicated in bold italic text) since the UE determines that at least slice number 1 is the first slice in the allowed / requested S-NSSAI. [Table 6] · The UE applies a dedicated reselection priority corresponding to the first slice for which per-slice reselection priority is configured. Example: As shown in Table 7 below, the UE selects and applies a dedicated reselection priority for slice number 2 (indicated in bold italic text) since the UE determines that at least slice number 2 is the first slice for which a dedicated priority is provided. [Table 7]

[0041] Example Item 2.4: Use of supported slice information in RRCRelease messages (for the case when no dedicated priority is configured for any slice) · The UE shall consider (or decide) that the frequency with the highest number of supported slices overlapping with the granted / requested S-NSSAI is associated with the highest priority. Example: As shown in Table 8 below, the UE considers (or determines) that frequency F3 (indicated in bold italic text) is associated with the highest priority because the UE determines that F3 has at least the maximum number of supported slices overlapped with the allowed / requested S-NSSAI, and F3 remains associated with the highest priority within the time window when the timer has not expired, which is configured (or indicated) together with the supported slices information in the RRCRelease message. [Table 8] · The UE shall consider (or decide) that the frequency supporting the first slice in the granted / requested S-NSSAI is associated with the highest priority. Example: As shown in Table 9 below, the UE considers (or determines) that frequency F2 (indicated in bold italic text) is associated with the highest priority because the UE determines that at least F2 supports the first slice in the Allowed / Requested S-NSSAI. F2 remains associated with the highest priority within the time window when the timer has not expired and the timer is configured (or indicated) together with the supported slices information in the RRCRelease message. [Table 9] · If more than one frequency supports the first slice in the authorized / requested S-NSSAI, the frequency configured with a higher reselection priority (e.g., dedicated reselection priority) shall be considered as the highest priority. Example: As shown in Table 10 below, both F2 and F3 support slice number 1 (e.g., the first slice in the granted / requested S-NSSAI), but the dedicated reselection priority configured for F3 (indicated in bold italic text) is higher than that of F2. The UE assumes (or determines) that F3 is associated with the highest priority within the time window when the timer has not expired and the timer is configured together with the supported slice information in the RRCRelease message. [Table 10]

[0042] Example Item 2.5: Use of Per-Slice Redirection Target Information in RRCRelease Messages The UE applies redirection target information corresponding to the first slice in the allowed / requested S-NSSAI, if configured. In some embodiments, for each of the multiple slices, the redirection target information may indicate a frequency as a target for cell (re)selection for the slice. In some embodiments, for each of the multiple slices, the redirection target information may indicate a single frequency to be used for the cell (re)selection technique for the slice. If no redirection target information is configured for the first slice, the UE applies common redirection target information. Example: As shown in Table 11 below, the UE applies the redirection target information configured for slice number 1 (shown in bold italic text) since the UE determines that at least slice number 1 is the first slice in the allowed / requested S-NSSAI. [Table 11] The UE applies the redirection target information corresponding to the first slice in which a per-slice redirection target is configured. Example: As shown in Table 12 below, the UE applies the redirection target configured for slice number 2 (shown in bold italic text) since the UE determines that at least slice number 2 is the first slice with specific redirection target information configured among the slices in the allowed / requested S-NSSAI. [Table 12]

[0043] Example item 3: In operation 102 of FIG. 1, the RACH configuration per slice / slice group / access category / access category group / UE type may include any one or more of the following: · 2-step and / or 4-step RACH common and dedicated resources (e.g. RACH Occasions (ROs) in frequency and time domain, and / or preambles) for slices / slice groups / access categories / access category groups / UE types / service types. · The UE type may be a UE with reduced capabilities, or a UE supporting coverage enhancement, or a UE supporting small data transmission, or a UE initiating small data transmission. Separate RO by prach-ConfigurationIndex / msg1-FDM / msg1-FrequencyStart / msgA-PRACH-ConfigurationIndex / msgA-RO-FDM / msgA-RO-FrequencyStart in addition to the existing RACH-ConfigGeneric for slice / slice group / access category / access category group / specific UE type. Separate preambles per slice / slice group / access category / access category group / UE type in addition to the existing totalNumberOfRA-Preambles. ○ Example 1: ra-PreambleStartIndex and number of preambles to be used for a certain slice / slice group / access category / access category group / UE type. ○ Example 2: ra-PreambleStartIndex and ra-PreambleEndIndex of the preamble to be used for a certain slice / slice group / access category / access category group / UE type. · When associating an existing preamble with a slice / slice group / access category / access category group / UE type, the preamble in the following example is within the existing totalNumberOfRA-Preambles. ○ Example 1: ra-PreambleStartIndex and number of preambles to be used for a certain slice / slice group / access category / access category group / UE type. ○ Example 2: ra-PreambleStartIndex and ra-PreambleEndIndex of the preamble to be used for a certain slice / slice group / access category / access category group / UE type. Associate existing ROs to slices / slice groups / access categories / access category groups / UE types / service types by configuring sliceAssociationPeriod / sliceGroupAssociationPeriod / accessCategoryAssociationPeriod / accessCategoryGroupAssociationPeriod / UEtypeAssociationPeriod / servicetypeAssociationPeriod=N×PRACH association period (N=1,2,3,···). sliceAssociationPeriodIndex / sliceGroupAssociationPeriodIndex / accessCategoryAssociationPeriodIndex / accessCategoryGroupAssociationPeriodIndex / UEtypeAssociationPeriodIndex / servicetypeAssociationPeriodIndex will be configured for each slice / slice group / access category / access category group / UE type. ra-PreambleStartIndex and number of preambles to be used for a slice + sliceAssociationPeriod and sliceAssociationPeriodIndex; ra-PreambleStartIndex and number of preambles to be used for a slice group + sliceGroupAssociationPeriod and sliceGroupAssociationPeriodIndex; ra-PreambleStartIndex and number of preambles to be used for an access category + accessCategoryAssociationPeriod and accessCategoryAssociationPeriodIndex; ra-PreambleStartIn dex and number +accessCategoryGroupAssociationPeriod and accessCategoryGroupAssociationPeriodIndex; ra-PreambleStartIndex and number +UETypeAssociationPeriod and UETypeAssociationPeriodIndex of preambles to be used for a UE type; or ra-PreambleStartIndex and number +serviceTypeAssociationPeriod and serviceTypeAssociationPeriodIndex of preambles to be used for a service type, associating an existing RO / preamble with a slice / slice group / access category / access category group / UE type / service type by configuring A network (NW) or NW device such as a base station can define RACH resource identifiers (IDs) and assign them to several RACH occasions and / or preambles in frequency and / or time domain. For a slice / slice group / access category / access category group / UE type / service type, one or more RACH resource IDs are configured to reserve RACH resources specific to this slice / slice group / access category / access category group. ○ One or more RACH resource IDs may also be configured by the NW for a particular UE type, e.g., a UE with reduced capabilities, a UE supporting coverage enhancement, or a UE supporting small data transmission, or a UE initiating small data transmission, or for a particular service, e.g., small data transmission. The NW may transmit one or more RACH resource IDs in a paging message / paging DCI / short message for each paging record to indicate the RACH resource to be used when the paged UE initiates random access to respond to the paging. RACH resource ID can be explicitly assigned by the NW, or it can be an index from a RACH resource list, e.g., index 0 refers to the first RACH resource in the list, index 1 refers to the second RACH resource in the list, etc. Use case indication may be provided for each RACH resource (e.g. RACH occasion in frequency and / or time domain and / or preamble) indicating whether the RACH resource can be used by certain UE type / service type / slice / slice group / access category group / access category. o The indication can be provided in an explicit way from the NW to the UE by providing an ENUMERATED value or a bitmap for each UE type / service type / slice / slice group / access category group / access category, where each bit points to one UE type / service type / slice / slice group / access category group / access category: For example, the following indications can be configured for a certain RACH resource: appliedtoRedCap ENUMERATED {true}, when set to true indicates that this RACH resource can be used by RedCap UEs. appliedtoCE ENUMERATED {true}, when set to true, indicates that this RACH resource can be used by UEs that support coverage enhancement. appliedtoSDT ENUMERATED {true}, when set to true indicates that this RACH resource can be used by the UE to initiate small data transmission (SDT). ○appliedtosliceBitmap BIT STRING (SIZE (maxNumberofsupportedslice)) OPTIONAL, the first bit in the bitmap with value 1 indicates that the RACH resource may be applied for the first slice in the supported slice list, the second bit in the bitmap with value 1 indicates that the RACH resource applies for the second slice in the supported slice list, etc. ○ appliedtoslicegroupBitmap BIT STRING (SIZE (maxNumberofsupportedslicegroup)) OPTIONAL, the first bit in the bitmap with value 1 indicates that the RACH resource may be applied for the first slice group in the supported slice group list, the second bit in the bitmap with value 1 indicates that the RACH resource may be applied for the second slice group in the supported slice group list, etc. appliedtoaccesscategoryBitmap BIT STRING (SIZE (maxNumberofsupportedaccesscategories)) OPTIONAL, the first bit in the bitmap with value 1 indicates that the RACH resource may be applied for the first access category in the supported access category list, the second bit in the bitmap with value 1 indicates that the RACH resource may be applied for the second access category in the supported access category list, etc. appliedtoaccesscategorygroupBitmap BIT STRING (SIZE (maxNumberofsupportedaccesscategorygroup)) OPTIONAL, the first bit in the bitmap with value 1 indicates that the RACH resource may be applied for the first access category group in the supported slice list, the second bit in the bitmap with value 1 indicates that the RACH resource may be applied for the second access category group in the supported access category group list, etc. o The indication can also be provided in an implicit way, for example some Msg3 repetition related configuration (used by UEs supporting coverage enhancement) can be provided together with the RACH resources, so that UEs supporting coverage enhancement will be aware that such RACH resources can be used. The following RA-RNTI calculation can be defined to distinguish slices / slice groups / access categories / access category groups: RA-RNTI=1+s_id+14×t_id+14×80×f_id+14×80×8×ul_carrier_id+2×14×80×8×slice_id / slicegroup_id / access category_id / access category_group_id / ue_type_id / service_type_id, where s_id is the index of the first OFDM symbol of the PRACH occasion (0≦s_id<14), t_id is the index of the first slot of the PRACH occasion in the system frame (0≦t_id<80), and the subcarrier spacing for determining t_id is TS Based on the values ​​of μ that may be specified in section 5.3.2 in 38.211, f_id is the index of the PRACH occasion in the frequency domain (0≦f_id<8), and ul_carrier_id is the UL carrier used for random access preamble transmission (0 for NUL carrier and 1 for SUL carrier). Random access prioritization configurations for slices / slice groups / access categories / access category groups (e.g., powerRampingStepHighPriority and scalingFactorBI). Other random access related parameters for slices / slice groups / access categories / access category groups msgA-TransMax msgA-RSRP-Threshold

[0044] Exemplary Item 4: In operation 104 of FIG. 1, the UE applies a RACH configuration per slice / slice group / access category / access category group / UE type / service type during a random access procedure, which may include the UE performing any of the following operations in exemplary items 4.1-4.4.

[0045] Example Item 4.1: RACH Type Selection For the cases when a slice / slice group / access category / access category group / UE type / service type is configured with either 2-step or 4-step RACH resources, the UE will apply the corresponding configuration (2-step or 4-step) for a certain slice / slice group / access category / access category group / UE type / service type. For the case when a slice / slice group / access category / access category group / UE type / service type is configured with both 2-step and 4-step RACH resources, the UE needs to choose between 2-step and 4-step. · If the BWP selected for the random access procedure consists of both 2-step and 4-step RA type random access resources for the intended slice / slice group / access category / access category group / UE type / service type, the UE shall use the cell specific msgA-RSRP-Threshold to select the RACH type. For example, if the downlink path loss metric RSRP is above msgA-RSRP-Threshold, set RA_TYPE to 2-stepRA. · The UE selects the RACH type using the msgA-RSRP-Threshold configured for this intended slice / slice group / access category / access category group / UE type / service type.

[0046] Example Item 4.2: RACH Type Fallback When slice / slice group / access category / access category group / UE type / service type are configured with two-step RACH resources, · 2-step RACH failure: If random access fails N (configured by msgA-TransMax) times for the intended slice / slice group / access category / access category group / UE type / service type configured with 2-step RACH resources, the UE shall perform 2-step / 4-step RACH using common resources (e.g. not slice / slice group / access category / access category group / UE type / service type specific). · 2-step RACH fallback to 4-step RACH: The NW indicates fallbackRAR in MSGB, the UE will get the MAC PDU and transmit it from the MSGA buffer, store it in the MSG3 buffer and continue to transmit MSG3. For the case when a slice / slice group / access category / access category group / UE type / service type consists of both 2-step and 4-step RACH resources, 2-step RACH failure: if for the intended slice / slice group / access category / access category group / UE type / service type a 2-step RACH is selected based on msgA-RSRP-Threshold (slice / slice group / access category / access category group / UE type / service type specific / cell specific) but random access fails N (configured by msgA-TransMax) times: Option 1: The UE shall perform 4-step RACH using resources configured for the same slice / slice group / access category / access category group / UE type / service type as that used by 2-step RACH, and if random access using slice / slice group / access category / access category group / UE type / service type specific 4-step RACH resources fails N (configured by preambleTransMax) times, the UE shall perform random access based on 2-step / 4-step common RACH resources. Option 2: The UE will perform a 2-step RACH using common resources, and if random access using the common 2-step RACH resources fails N (configured by msgA-TransMax) times, the UE will perform random access based on 4-step slice-specific RACH resources. · 2-step fallback to 4-step RACH: The NW indicates fallbackRAR in MSGB, the UE will get the MAC PDU, transmit it from the MSGA buffer, store it in the MSG3 buffer and continue to transmit MSG3. 4-step slice-specific failure: if for the intended slice / slice group / access category / access category group / UE type / service type a 4-step RACH is selected based on msgA-RSRP-Threshold (slice / slice group / access category / access category group / UE type / service type specific / cell specific) but random access fails N (configured by msgA-TransMax) times, Option 1: The UE performs a 4-step RACH using common RACH resources. Option 2: The UE performs 2-step / 4-step RACH using common RACH resources.

[0047] Example Item 4.3: RACH Prioritization Parameter Selection For the case when both RACH prioritization parameters for MPS / MCS and RACH prioritization parameters for the intended slice / slice group / access category / access category group / UE type / service type are configured: [Table 12-1] The access identification in the above ASN.1 code refers to the MPS / MCS. · Option 1: MPS / MCS UE uses powerRampingStepHighPriority and scalingFactorBI configured for MPS / MCS. · Option 2: MPS / MCS UE uses powerRampingStepHighPriority and scalingFactorBI configured for the intended slice / slice group / access category / access category group / UE type / service type. Option 3: MPS / MCS UE uses the maximum value {powerRampingStepHighPriority for AI, powerRampingStepHighPriority for slice / slice group / access category / access category group / UE type / service type} and the minimum value {scalingFactorBI for AI, scalingFactorBI for slice / slice group / access category / access category group / UE type / service type}. Option 4: In the RACH parameters for MPS / MCS / slice / slice group / access category / access category group / UE type / service type, the UE applies {scalingFactorBI, powerRampingStepHighPriority} configured with the maximum value of powerRampingStepHighPriority. Option 5: Among the RACH parameters for MPS / MCS / slice / slice group / access category / access category group / UE type / service type, the UE applies {scalingFactorBI, powerRampingStepHighPriority} set using the minimum value of scalingFactorBI. For the case when the NW provides two or more sets of RACH prioritization parameters for the MPS / MCS, and each set of RACH prioritization parameters for the MPS / MCS is associated with a slice / slice group / access category / access category group / UE type / service type and a common RACH prioritization parameter for the MPS / MCS that is applicable for all slices / slice groups / access categories / access category groups / UE types / service types, the MPS / MCS UE selects a RACH prioritization parameter for the MPS / MCS and associates it with the intended slice. [Table 12-2]

[0048] Example Item 4.4: RACH Resource Selection The UE shall consider one or more of the following information when selecting the RACH resource to be used for random access: Intended Slices / Slice Groups / Access Categories / Access Category Groups UE type, for example a UE with reduced capabilities, or a UE supporting enhanced coverage, or a UE supporting small data transmission, or a UE initiating small data transmission. Service type, e.g. small data transmission. For example, a UE with reduced capability wanting to initiate small data transmission in slice number 1 will select the applicable RACH resource for the reduced capability UE, small data transmission service and slice number 1. For example, a UE with reduced capability wanting to initiate small data transmission in slice number 1 will select the applicable RACH resource for the reduced capability UE, small data transmission service, or slice number 1. For a UE that initiates a random access procedure to respond to paging, the NW may indicate the slice / slice group / access category / access category group / UE type / service type in the paging message / paging DCI / short message.

[0049] The following sections describe some implementation examples. The example headings for the various sections below are used to facilitate understanding of the disclosed subject matter and do not limit the scope of the claimed subject matter in any way. Thus, one or more features of one example section can be combined with one or more features of another example section. Furthermore, although 5G terminology is used for clarity of explanation, the techniques disclosed herein are not limited to only 5G technology and may be used in wireless systems implementing other protocols.

[0050] (I. Implementation Example 1:)

[0051] The UE receives supported slice information with per-slice priorities of neighbor cells in the system information as shown below in Table 13. The UE selects the first slice (indicated in bold italic text) in the allowed / requested S-NSSAI and applies the reselection priority configured for the first slice. [Table 13]

[0052] Supported slice information, with or without priority per slice for intra-frequency cells, can be provided in SIB2 as shown in bold italic text in the example given below. [Table 13-1]

[0053] Supported slice information, with or without priority per slice for inter-frequency cells, can be provided in SIB4 as shown in bold italic text in the example given below. [Table 13-2] [Table 13-3]

[0054] Supported slice information, with or without per-slice priority for inter-RAT cells, may be provided in SIB5 as shown in bold italic text in the example given below. [Table 13-4]

[0055] (II. Implementation Example 2:)

[0056] The UE receives the supported slice information without dedicated reselection priority per slice of neighboring cells (as shown in Table 14 below) along with timer txxx in the RRCRelease message. [Table 14]

[0057] The UE shall start Txxx with the set value for txxx and, before Txxx expires, shall consider the frequency with the maximum number of supported slices overlapping with the granted / requested S-NSSAI to be associated with the highest priority.

[0058] The supported slice information, with or without per-slice priority for neighboring cells, can be provided in the RRCRelease message as shown in bold italic text in the example given below. [Table 14-1]

[0059] (III. Implementation Example 3:)

[0060] The UE receives the per slice redirection configuration (as shown in Table 15 below) along with timers txxx in the RRCRelease message. [Table 15]

[0061] The UE starts Txxx with the value set to txxx, and before Txxx expires, applies the redirection configuration for the first slice (eg, slice number 2) for which redirection target information is configured.

[0062] Per-slice redirection configuration can be provided in RRCRelease as shown in bold italic text in the example provided below. [Table 15-1]

[0063] (IV. Implementation Example 4:)

[0064] The UE receives the configured 2-step CFRA resource or 4-step CFRA resource for the intended slice, and initiates random access to the target cell after handover using the 2-step CFRA resource or 4-step CFRA resource.

[0065] The 2-step or 4-step CFRA resources per slice may be provided in the RRCReconfiguration message as shown in bold italics in the example given below.

[0066] CFRA-4 Step-ASN.1 Example 1: [Table 15-2] [Table 15-3]

[0067] CFRA-4 Step-ASN.1 Example 2: [Table 15-4] [Table 15-5]

[0068] CFRA-2 Step-ASN.1 Example 1: [Table 15-6]

[0069] CFRA-2 Step - ASN.1 Example 2: [Table 15-7]

[0070] Exemplary techniques described below are for performing cell (re)selection and / or random access using cell (re)selection information and / or RACH configurations provided for each slice in a plurality of slices. In the exemplary techniques described below, the terms "slice" and "slices" can be replaced with "slice group" and "slice groups", or "access category" and "access categories", or "access category group" and "access category groups", or "UE type" and "UE types", or "service type" or "service types", respectively.

[0071] 2 illustrates an example flowchart for a method 200 of implementing a slice-aware cell selection technique. Operation 202 includes implementing, by a communications device, the cell selection technique using a set of cell selection-related information associated with a slice, the set of cell selection-related information being from a plurality of sets of cell selection-related information associated with a plurality of slices, each set of cell selection-related information being associated with a slice from the plurality of slices.

[0072] In some embodiments of the method 200, the communications device selects or determines a set of cell selection related information associated with a slice from a plurality of sets of cell selection related information related to the plurality of slices, and performs a cell selection technique using the set of cell selection related information associated with the slice, each set of cell selection related information being associated with a slice from the plurality of slices.

[0073] In some embodiments of method 200, the multiple sets of cell selection related information include supported slice information for each slice from the multiple slices, where for each slice of the multiple slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. In some embodiments of method 200, the multiple sets of cell selection related information include cell selection priority information for each slice from the multiple slices, where for each slice of the multiple slices, the cell selection priority information indicates a cell selection priority value for the slice, where the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. In some embodiments of method 200, the multiple sets of cell selection related information include redirection target information for each slice from the multiple slices, where for each slice of the multiple slices, the redirection target information indicates a frequency to use for a cell selection technique for the slice. In some embodiments of method 200, the communications device performs a cell selection technique with the cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, the cell selection priority value being associated with a slice that is first in order in a list of slices in an allowed single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI.

[0074] In some embodiments of the method 200, the communication device performs a cell selection technique with the cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, the cell selection priority value being associated with any one of the following associated with a slice that is first in order in a list of slices in the authorized single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI: a slice group, an access category, and an access category group. In some embodiments of the method 200, the communication device performs a cell selection technique with the cell by using a cell selection priority value of (1) the cell or (2) a frequency deployed by the cell, the slice being associated with a cell selection priority value, the slice being first in order associated with a cell selection priority value in a list of slices in the authorized single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI. In some embodiments of the method 200, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency being associated with the cell, the frequency having the highest priority in response to the frequency being associated with an allowed single network slice selection assistance information (S-NSSAI) or a maximum number of supported slices from a requested S-NSSAI.

[0075] In some embodiments of the method 200, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency associated with the cell, the frequency having the highest priority in response to the frequency being supported by a slice that is first in the list of slices in the allowed single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI. In some embodiments of the method 200, the communications device performs a cell selection technique with a cell by using a frequency having a highest priority, the frequency associated with the cell, the frequency having the highest priority in response to the frequency being supported by any one of a slice group, an access category, and an access category group associated with a slice that is first in the list of slices in the allowed single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI.

[0076] 3 illustrates an example flowchart of a method 300 for implementing a slice-aware random access technique. Operation 302 includes implementing the random access technique using a set of random access channel (RACH) configurations associated with a slice, by a communication device, the set of RACH configurations from a plurality of sets of RACH configurations related to a plurality of slices, each set from the plurality of sets of RACH configurations being associated with a slice from the plurality of slices.

[0077] In some embodiments of the method 300, the communications device selects or determines a set of RACH configurations for a slice from a plurality of sets of RACH configurations associated with a plurality of slices, each set of RACH configurations being associated with a slice from the plurality of slices; and performs the random access technique using the set of RACH configurations associated with the slice.

[0078] In some embodiments of the method 300, the multiple sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice for the multiple slices, the resources including locations of RACH occasions in the frequency domain and the time domain, the resources being common resources associated with the multiple communication nodes or dedicated resources assigned to the communication nodes. In some embodiments of the method 300, the multiple sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the multiple slices. In some embodiments of the method 300, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices and a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices.

[0079] In some embodiments of the method 300, the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from the multiple slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments of the method 300, the communication device performs the random access technique by performing a two-step random access technique or by performing a four-step random access technique. In some embodiments of the method 300, the communication device performs the two-step random access technique or the four-step random access technique by using common resources associated with the multiple communication nodes in response to the communication device determining that the random access technique performed using one set of RACH configurations associated with the slice resulted in a certain number of failed results. In some embodiments of the method 300, the communication device performs the four-step random access technique by using another set of RACH configurations associated with the slice or by using common resources associated with the multiple communication nodes in response to the communication device determining that the two-step random access technique performed using one set of RACH configurations associated with the slice resulted in a certain number of failed results.

[0080] In some embodiments of the method 300, the communications device performs the random access technique by using a first set of RACH prioritization parameters configured for a communications device configured for Multimedia Priority Services (MPS) or Mission Critical Services (MCS), or the communications device performs the random access technique by using a second set of RACH prioritization parameters configured for a slice.

[0081] 4A illustrates a flowchart of a method 400 for a network device to provide multiple sets of cell selection related information for multiple slices for a communications device to implement a slice-aware cell selection technique. Operation 402 includes transmitting, by the network device, multiple sets of cell selection related information related to the multiple slices, each set of cell selection related information being associated with one slice from the multiple slices.

[0082] In some embodiments of method 400, the multiple sets of cell selection related information include supported slice information for each slice from the multiple slices, where for each slice of the multiple slices, the supported slice information indicates whether the slice is supported by multiple cells or by multiple frequencies. In some embodiments of method 400, the multiple sets of cell selection related information include cell selection priority information for each slice from the multiple slices, where for each slice of the multiple slices, the cell selection priority information indicates a cell selection priority value for the slice, where the cell selection priority value indicates a priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. In some embodiments of method 400, the multiple sets of cell selection related information include redirection target information for each slice from the multiple slices, where for each slice of the multiple slices, the redirection target information indicates a frequency to use for a cell selection technique for the slice.

[0083] In some embodiments of the method 400, the sets of cell selection related information are transmitted to the communication devices comprising the communication device via system information. In some embodiments of the method 400, the sets of cell selection related information are transmitted via radio resource control (RRC) signaling dedicated to the communication device.

[0084] 4B shows a flowchart of a method 410 for a network device to provide a plurality of sets of RACH configurations for a plurality of slices for the communication device to perform a slice-aware random access technique. Operation 412 includes performing, by the network device, a first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with the plurality of slices, each set from the plurality of sets of RACH configurations being associated with one slice from the plurality of slices. Operation 414 includes receiving, by the network device, a random access preamble from the communication device using one set of RACH configurations associated with the slice from the plurality of sets of RACH configurations.

[0085] In some embodiments of the method 410, the method further includes performing, by the network device, a second transmission comprising a message to the communication device, the message comprising an identifier of a set of RACH configurations associated with a slice to be used by the communication device, and the random access preamble is received in response to the second transmission of the message. In some embodiments of the method 410, the message is included in a paging message or a paging downlink control information (DCI) or a short message. In some embodiments of the method 410, the multiple sets of RACH configurations include resources for performing a two-step random access technique or a four-step random access technique for each slice for the multiple slices, the resources including locations of RACH occasions in the frequency domain and the time domain, and the resources being common resources associated with the multiple communication nodes or dedicated resources assigned to the communication nodes. In some embodiments of the method 410, the multiple sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the multiple slices.

[0086] In some embodiments of the method 410, the multiple sets of RACH configurations include a first value indicative of a maximum number of failed random access attempts allowed for each slice from the multiple slices and a second value indicative of a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments of the method 410, the multiple sets of RACH configurations include a first value indicative of a maximum number of failed random access attempts allowed for each slice from the multiple slices or a second value indicative of a threshold reference signal received power (RSRP) for each slice from the multiple slices. In some embodiments of the method 410, the first transmission comprising the multiple sets of RACH configurations is performed via system information to the multiple communication devices comprising the communication devices. In some embodiments of the method 410, the first transmission comprising the multiple sets of RACH configurations is performed via radio resource control (RRC) signaling dedicated to the communication devices.

[0087] In some embodiments, an apparatus for wireless communication includes a processor configured to perform the operations recited with respect to methods 200-410 and in the embodiments described in this patent document. In some embodiments, a non-transitory computer readable program storage medium has code stored thereon that, when executed by a processor, causes the processor to implement the operations recited with respect to methods 200-410 and in the embodiments described in this patent document.

[0088] FIG. 5 illustrates an example block diagram of a hardware platform 500 that may be part of a network node (e.g., a network device such as a base station) or a communication device (e.g., a user equipment). The hardware platform 500 includes at least one processor 510 and a memory 505 having stored instructions. The instructions, when executed by the processor 510, configure the hardware platform 500 to perform the operations described in FIGS. 1-4B and in various embodiments described in this patent document. The transmitter 515 transmits or transmits information or data to another node. For example, a network node transmitter can transmit a message to a user equipment. The receiver 520 receives information or data transmitted or transmitted by another node. For example, a user equipment can receive a message from a network node.

[0089] The implementation as discussed above may be applied to wireless communication. Figure 6 illustrates an example of a wireless communication system (e.g., a 5G or NR cellular network) including a base station 620 and one or more user equipments (UEs) 611, 612, and 613. In some embodiments, the UE accesses a BS (e.g., a network) using a communication link to the network (as depicted by dashed arrows 631, 632, 633, sometimes referred to as the uplink direction), which then enables subsequent communication from the BS to the UE (e.g., shown in the network to UE direction, sometimes referred to as the downlink direction, as depicted by arrows 641, 642, 643). In some embodiments, the BS transmits information to the UE (as depicted by arrows 641, 642, 643, sometimes referred to as the downlink direction), which then enables subsequent communication from the UE to the BS (e.g., shown in the UE to BS direction, sometimes referred to as the uplink direction, as depicted by dashed arrows 631, 632, 633). The UE may be, for example, a smartphone, a tablet, a mobile computer, a Machine-to-Machine (M2M) device, an Internet of Things (IoT) device, and so on.

[0090] The UE may be, for example, a smartphone, a tablet, a mobile computer, a Machine-to-Machine (M2M) device, an Internet of Things (IoT) device, and so on.

[0091] The following sections describe additional exemplary technical example items as described in this patent document.

[0092] In some embodiments, the UE receives cell (re)selection information and / or RACH configuration per slice / slice group / access category / access category group / UE type, and the UE applies the cell (re)selection information and / or RACH configuration during the cell (re)selection and / or random access procedure.

[0093] In some embodiments, the cell (re)selection information per slice / slice group / access category / access category group / UE type further includes any one or more of the following: Supported slice information for each cell or frequency. Reselection priority for each slice / slice group / access category / access category group / UE type / service type. Redirection target information for each slice / slice group / access category / access category group / UE type / service type.

[0094] In some embodiments, the UE applying the per-slice cell (re)selection information during the cell (re)selection procedure further includes any one or more of the following: · The UE applies the reselection priority corresponding to the first slice in the allowed / requested S-NSSAI or the reselection priority corresponding to the slice group / access category / access category group to which the first slice belongs. ·The UE applies the reselection priority corresponding to the first slice / slice group / access category / access category group for which per-slice reselection priority is configured. · The UE shall consider (or decide) that the frequency with the highest number of supported slices overlapping with the granted / requested S-NSSAI is associated with the highest priority. · The UE shall consider (or decide) that the frequency supporting the first slice in the allowed / requested S-NSSAI or the slice group / access category / access category group to which the first slice belongs is associated with the highest priority.

[0095] In some embodiments, the RACH configuration per slice / slice group / access category / access category group / UE type further includes any one or more of the following: · 2-step and / or 4-step RACH common and dedicated resources (RACH occasions in frequency and time domain, and / or preambles) for slices / slice groups / access categories / access category groups / UE types / service types. Random access prioritization configurations (e.g. powerRampingStepHighPriority and scalingFactorBI) for slices / slice groups / access categories / access category groups / UE types / service types. · msgA-TransMax or msgA-RSRP-Threshold for slice / slice group / access category / access category group / UE type / service type.

[0096] In some embodiments, the UE applying a RACH configuration per slice / slice group / access category / access category group / UE type / service type during the random access procedure further includes any one or more of the following: · The UE selects 2-step or 4-step random access type. When random access using slice / slice group / access category / access category group / UE type / service type specific RACH resources fails a certain number of times, the UE performs two steps or four steps using common resources. When the UE fails a certain number of times in the 2-step random access using a slice / slice group / access category / access category group / UE type / service type specific RACH resource, the UE performs a 4-step random access using a slice / slice group / access category / access category group / UE type / service type specific 4-step RACH resource, and the 4-step random access is performed using the same slice / same slice group / same access category / same access category group / UE type / service type as that used by the 2-step random access. · The UE selects between RACH prioritization parameters configured for the MPS / MCS UE and RACH prioritization parameters configured for slice / slice group / access category / access category group / UE type / service type.

[0097] The term "exemplary" is used herein to mean "an example of," and does not imply an ideal or preferred embodiment, unless otherwise stated.

[0098] Some of the embodiments described herein are described in the general context of a method or process that may be implemented by a computer program product embodied in a computer-readable medium that includes computer-executable instructions, such as program code, executed by a computer in a networked environment in one embodiment. The computer-readable medium may include removable and non-removable storage devices, including, but not limited to, read-only memory (ROM), random access memory (RAM), compact disks (CDs), digital versatile disks (DVDs), and the like. Thus, the computer-readable medium may include non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, and the like that perform particular tasks or implement particular abstract data types. Computer or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. A particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

[0099] Some of the disclosed embodiments can be implemented as devices or modules using hardware circuits, software, or a combination thereof. For example, hardware circuit implementations can include discrete analog and / or digital components integrated, for example, as part of a printed circuit board. Alternatively or additionally, the disclosed components or modules can be implemented as application specific integrated circuits (ASICs) and / or as field programmable gate array (FPGA) devices. Some implementations can additionally or alternatively include digital signal processors (DSPs), which are specialized microprocessors with architectures optimized for the operational needs of digital signal processing associated with the disclosed functionality of the present application. Similarly, various components or subcomponents within each module can be implemented in software, hardware, or firmware. Connectivity between modules, and / or components within a module, can be provided using any one of the connectivity methods and mediums known in the art, including, but not limited to, communication via the Internet, wired, or wireless networks using appropriate protocols.

[0100] Although this document contains many details, these should not be construed as limitations on the scope of the claimed invention or the subject matter that may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features described herein in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as operating in a combination and may even be initially claimed as such, one or more features from the claimed combination may, in some cases, be deleted from the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination. Similarly, although operations are depicted in the figures in a particular order, this should not be understood as requiring such operations to be performed in the particular order shown, or in a sequential order, or that all of the illustrated operations be performed, to achieve desired results.

[0101] Only some implementations and examples have been described; other implementations, enhancements, and variations can be made based on what is described and illustrated in this disclosure.

Claims

1. A method of wireless communication, the method including: a communications device performing a random access technique using a set of random access channel (RACH) configurations associated with a slice group or a user equipment (UE) type or a service type; The set of RACH configurations is from a plurality of sets of RACH configurations associated with a plurality of slice groups or a plurality of UE types or a plurality of service types; Each set from the plurality of sets of the RACH configurations is associated with one slice group from the plurality of slice groups or the plurality of UE types or the plurality of service types; The communication device includes: a first set of RACH prioritization parameters configured for said communication device configured for Multimedia Priority Services (MPS) or Mission Critical Services (MCS); or A second set of RACH prioritization parameters configured for a slice group.

4. A method for performing the random access technique by using:

2. The method of claim 1, wherein the first set of RACH prioritization parameters includes a power ramping step high priority and a scaling factor configured for the MPS or the MCS.

3. The method described in claim 2, wherein the communications device applies a maximum value to the power ramping step high priority.

4. The method of claim 2, wherein the communications device applies a minimum value to the scaling factor.

5. The method described in claim 1, wherein the multiple sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of a plurality of slices.

6. The method of claim 1, wherein the multiple sets of RACH configurations include a first value indicating a maximum number of failed random access attempts allowed for each slice from a plurality of slices, and a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices.

7. The method of claim 1, wherein the communications device performs a two-step random access technique or a four-step random access technique by using common resources associated with a plurality of communications nodes in response to the communications device determining that the random access technique performed using the one set of the RACH configurations associated with a slice resulted in a certain number of failed results.

8. The method of claim 1, wherein in response to the communications device determining that a two-step random access technique performed using the one set of RACH configurations associated with a slice has resulted in a certain number of failed results, the communications device performs a four-step random access technique by using another set of RACH configurations associated with the slice or by using common resources associated with multiple communications nodes.

9. An apparatus for wireless communication, the apparatus comprising a processor, the processor being configured to implement a method according to any one of claims 1 to 8.

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