Slice Recognition Cell Selection and Random Access Techniques

Abstract

Techniques are described in relation to implementing slice-aware cell selection or slice-aware random access techniques. An example wireless communication method includes implementing, 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 related to a plurality of slices, each set of cell selection-related information being associated with a slice from the plurality of slices.

Description

Technical Field

[0001] The present disclosure generally relates to digital wireless communication.

Background Art

[0002] Mobile telecommunications technology is making the world more connected and networked. Compared with existing wireless networks, next-generation systems and wireless communication techniques will need to support a much wider range of use case characteristics and provide more complex and advanced access requirements and flexibility.

[0003] Long-Term Evolution (LTE) is a standard for wireless communication for mobile devices and data terminals developed by the Third Generation Partnership Project (3GPP (registered trademark)). LTE-Advanced (LTE-A) is a wireless communication standard that extends the LTE standard. The fifth-generation wireless system, known as 5G, is working to evolve the LTE and LTE-A wireless standards to support higher data rates, a large number of connections, ultra-low latency, high reliability, and other newly emerging business requirements.

Summary of the Invention

Means for Solving the Problems

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

[0005] A first exemplary wireless communication method is for a communication device to perform a cell selection technique using a set of cell selection related information associated with a slice, where the 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.

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

[0007] In some embodiments, the plurality of sets of cell selection related information includes supported slice information for each slice from the plurality of slices, and for each slice of the plurality of slices, the supported slice information indicates whether the slice is supported by a plurality of cells or by a plurality of frequencies. In some embodiments, the plurality of sets of cell selection related information includes cell selection priority information for each slice from the plurality of slices, and for each slice of the plurality of slices, the cell selection priority information indicates a cell selection priority value for the slice, and the cell selection priority value indicates the priority of (1) a cell associated with the slice or (2) a frequency associated with the slice. In some embodiments, the plurality of sets of cell selection related information includes redirection target information for each slice from the plurality of slices, and 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. In some embodiments, the communication device implements a cell selection technique using a cell selection priority value of (1) a cell or (2) a frequency deployed by the cell, and the cell selection priority value is associated with the slice that is first in order in a list of slices in the permitted single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI.

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

[0009] In some embodiments, the communication device implements a cell selection technique using a cell by using the frequency with the highest priority, where the frequency is associated with the cell, and the frequency has the highest priority in response to being supported by a single network slice selection assistance information (S-NSSAI) for which the frequency is permitted or the slice that is first in the list of slices in the requested S-NSSAI. In some embodiments, the communication device implements a cell selection technique using a cell by using the frequency with the highest priority, where the frequency is associated with the cell, and 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 the slice that is first in the list of slices in the single network slice selection assistance information (S-NSSAI) for which the frequency is permitted or the requested S-NSSAI.

[0010] A second exemplary wireless communication method is for a communication device to implement a random access technique using one set of random access channel (RACH) configurations associated with a slice, where one set of RACH configurations is 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 is associated with one slice from the plurality of slices.

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

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

[0013] In some embodiments, the plurality of sets of RACH configurations include a first value indicating the maximum number of failed random access attempts permitted for each slice from a plurality of slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. In some embodiments, the communication device implements a random access technique by implementing a two-step random access technique or by implementing a four-step random access technique. In some embodiments, the communication device uses a common resource associated with a plurality of communication nodes in response to determining that a random access technique implemented using one set of RACH configurations associated with a slice has resulted in a number of failed attempts, to implement a two-step random access technique or a four-step random access technique. In some embodiments, the communication device uses another set of RACH configurations associated with the slice or uses a common resource associated with a plurality of communication nodes in response to determining that a two-step random access technique implemented using one set of RACH configurations associated with a slice has resulted in a number of failed attempts, to implement a four-step random access technique.

[0014] In some embodiments, the communication device implements a random access technique by using a first set of RACH prioritization parameters configured for a communication device configured for multimedia priority service (MPS) or mission critical service (MCS), or the communication device implements a random access technique by using a second set of RACH prioritization parameters configured for a slice.

[0015] A third exemplary wireless communication method is for a network device to transmit 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 one slice from the plurality of slices.

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

[0017] In some embodiments, the plurality of sets of cell selection related information is transmitted to a plurality of communication devices including a communication device via system information. In some embodiments, the plurality of sets of cell selection related information is transmitted via radio resource control (RRC) signaling dedicated to the communication device.

[0018] The fourth exemplary wireless communication method is for a network device to perform a first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with a plurality of slices, wherein each set from the plurality of sets of RACH configurations is associated with one slice from the plurality of slices, and for the network device to receive 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 comprises for the network device to perform a second transmission comprising a message to the communication device, the message comprising an identifier of one set of RACH configurations associated with the slice to be used by the communication device, and the random access preamble being received in response to the second transmission of the message. In some embodiments, the message is included in a paging message or paging downlink control information (DCI) or a short message. In some embodiments, the plurality of sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice of the plurality of slices, the resources including the location of RACH occasions in the frequency domain and the time domain, and the resources being common resources associated with a plurality of communication nodes or dedicated resources allocated to a communication node. In some embodiments, the plurality of sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the plurality of slices.

[0020] In some embodiments, a plurality of sets of RACH configurations include a first value indicating a maximum number of permitted failed random access attempts 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. In some embodiments, a plurality of sets of RACH configurations include a first value indicating a maximum number of permitted failed random access attempts for each slice from a plurality of slices or a second value indicating a threshold reference signal received power (RSRP) for each slice from the plurality of slices. In some embodiments, a first transmission comprising a plurality of sets of RACH configurations is performed on a plurality of communication devices comprising communication devices via system information. In some embodiments, a first transmission comprising a plurality of sets of RACH configurations is performed via radio resource control (RRC) signaling dedicated to a 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 included in the computer-readable storage medium, when executed by a processor, causes the processor to implement the methods described in this patent document.

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

[0023] The above and other aspects, and their implementations, are described in more detail by the drawings, the description, and the claims. The present invention provides, for example, the following. (Item 1) A wireless communication method, the method comprising: performing, by a communication device, a cell selection technique using a set of cell selection related information associated with a slice, wherein the 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, the wireless communication method. (Item 2) The plurality of sets of cell selection related information includes supported slice information for each slice from the plurality of slices, and for each slice of the plurality of slices, the supported slice information indicates whether the slice is supported by a plurality of cells or by a plurality of frequencies, the method according to Item 1. (Item 3) The plurality of sets of cell selection related information includes cell selection priority information for each slice from the plurality of slices, and for each slice of the plurality of slices, the cell selection priority information indicates a cell selection priority value for the slice, wherein the cell selection priority value indicates (1) a cell associated with the slice or (2) a priority of a frequency associated with the slice, the method according to Item 1. (Item 4) The plurality of sets of cell selection related information includes redirection target information for each slice from the plurality of slices, and 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, the method according to Item 1. (Item 5) The communication device performs the cell selection technique using the cell by using (1) the cell selection priority value of the cell or (2) a frequency deployed by the cell, wherein the cell selection priority value is associated with a slice that is first in order in a list of slices in a permitted single network slice selection assistance information (S-NSSAI) or a requested S-NSSAI, the method according to Item 1. (Item 6) The communication device performs the cell selection technique using the cell by using (1) a cell selection priority value of the cell or (2) a frequency deployed by the cell, The cell selection priority value is associated with any one of a slice group, an access category, and an access category group associated with the slice that is first in order in the list of slices in the permitted single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI, according to the method described in item 1. (Item 7) The communication device performs the cell selection technique using the cell by using (1) the cell or (2) the cell selection priority value of the frequency deployed by the cell. The slice is associated with the cell selection priority value. The slice is the first one in the order associated with the cell selection priority value in the list of slices in the permitted single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI, according to the method described in item 1. (Item 8) The communication device performs the cell selection technique using the cell by using the frequency with the highest priority. The frequency is associated with the cell. The frequency has the highest priority in response to the frequency being associated with the maximum number of slices supported by the permitted single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI, according to the method described in item 1. (Item 9) The communication device performs the cell selection technique using the cell by using the frequency with the highest priority. The frequency is associated with the cell. The frequency has the highest priority in response to the frequency being supported by the slice that is first in order in the list of slices in the permitted single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI, according to the method described in item 1. (Item 10) The communication device performs the cell selection technique using the cell by using the frequency with the highest priority. The frequency is associated with the cell. The method according to item 1, having 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 the single network slice selection assistance information (S-NSSAI) or the requested S-NSSAI for which the frequency is permitted. (Item 11) A wireless communication method, the method comprising: a communication device implementing a random access technique using one set of random access channel (RACH) configurations associated with a slice, wherein one set of the RACH configurations is 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 is associated with one slice from the plurality of slices. (Item 12) The plurality of sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice of the plurality of slices, the resources including the locations of RACH occasions in a frequency domain and a time domain, and the resources are common resources associated with a plurality of communication nodes or dedicated resources allocated to the communication nodes. (Item 13) The plurality of sets of RACH configurations include a random access prioritization configuration indicating a configuration regarding a prioritized random access procedure for each slice of the plurality of slices. (Item 14) The plurality of sets of RACH configurations include a first value indicating a maximum number of permitted failed random access attempts 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) The plurality of sets of RACH configurations include a first value indicating a maximum number of permitted failed random access attempts 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) The method according to 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) The method according to item 11, wherein the communication device implements a two-step random access technique or a four-step random access technique by using a common resource associated with a plurality of communication nodes in response to the communication device determining that the random access technique implemented using one set of the RACH configurations associated with the slice has resulted in a certain number of failed attempts. (Item 18) The method according to item 11, wherein the communication device implements a four-step random access technique by using another set of the RACH configurations associated with the slice or by using a common resource associated with a plurality of communication nodes in response to the communication device determining that the 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 attempts. (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 service (MPS) or mission critical service (MCS), or The method according to item 11, wherein the communication device implements the random access technique by using a second set of RACH prioritization parameters configured for a slice. (Item 20) A wireless communication method, the method comprising: transmitting, by a network device, a plurality of sets of cell selection related information related to a plurality of slices, wherein each set of cell selection related information is associated with one slice from the plurality of slices. (Item 21) The plurality of sets of cell selection related information includes supported slice information for each slice from the plurality of slices. For each of the plurality of slices, the supported slice information is the method according to item 20 indicating whether the slice is supported by a plurality of cells or by a plurality of 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 of the plurality of slices, the cell selection priority information indicates a cell selection priority value for the slice, The cell selection priority value is the method according to item 20 indicating the priority of (1) the cell associated with the slice or (2) the 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, For each of the plurality of slices, the redirection target information is the method according to item 20 indicating the frequency to be used for the cell selection technique for the slice. (Item 24) The plurality of sets of cell selection related information are transmitted to a plurality of communication devices equipped with the communication device via system information, according to any of items 20 - 23. (Item 25) The plurality of sets of cell selection related information are transmitted via radio resource control (RRC) signaling dedicated to the communication device, according to any of items 20 - 23. (Item 26) A wireless communication method, the method comprising: Performing a first transmission by a network device, comprising a plurality of sets of random access channel (RACH) configurations related to a plurality of slices, wherein each set from the plurality of sets of RACH configurations is associated with one slice from the plurality of slices; Receiving a random access preamble by the network device from a communication device using one set of the RACH configurations associated with the slice from the plurality of sets of RACH configurations; A wireless communication method including the above. (Item 27) Further comprising performing a second transmission by the network device, comprising a message to the communication device, The message comprising an identifier of one set of the RACH configurations associated with the slice to be used by the communication device. The random access preamble is the method according to item 26, which is received in response to the second transmission of the message. (Item 28) The message is the method according to item 27, which is included in a paging message or paging downlink control information (DCI) or a short message. (Item 29) The plurality of sets of RACH configurations include resources for implementing a two-step random access technique or a four-step random access technique for each slice of the plurality of slices, The resources include the location of RACH occasions in the frequency domain and the time domain, The resources are common resources associated with a plurality of communication nodes or dedicated resources allocated to the communication nodes, which is the method according to item 26. (Item 30) The plurality of sets of RACH configurations include a random access prioritization configuration indicating a configuration for a prioritized random access procedure for each slice of the plurality of slices, which is the method according to item 26. (Item 31) The plurality of sets of RACH configurations include a first value indicating the maximum number of permitted failed random access attempts 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, which is the method according to item 26. (Item 32) The plurality of sets of RACH configurations include a first value indicating the maximum number of permitted failed random access attempts 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, which is the method according to item 26. (Item 33) The first transmission with the plurality of sets of RACH configurations is performed on a plurality of communication devices equipped with the communication device via system information, which is the method according to any one of items 26 - 32. (Item 34) The first transmission with the plurality of sets of RACH configurations is performed via radio resource control (RRC) signaling dedicated to the communication device, which is the method according to any one of items 26 - 32. (Item 35) An apparatus for wireless communication comprising a processor configured to implement the method according to one or more of items 1 - 34. (Item 36) A non-transitory computer-readable program storage medium storing code which, when executed by a processor, causes the processor to implement the method according to one or more of Items 1-34.

Brief Description of the Drawings

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Figure 1

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[0031] Network slicing has been introduced in New Radio (NR), which is a concept for enabling differentiated processing according to each customer requirement. Using slicing, a Mobile Network Operator (MNO) can consider customers as belonging to different tenant types, and each of the different tenant types has different service requirements determined from the perspective of slice types that each tenant is eligible to use based on a Service Level Agreement (SLA) and a subscription.

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

[0033] Figure 1 shows an exemplary flowchart for performing cell (re)selection and / or random access procedures. Operation 102 includes the UE (or communication device) receiving slice-specific cell (re)selection information and / or RACH configuration. Operation 104 includes the UE applying the cell (re)selection information or RACH configuration, respectively, during the cell (re)selection or random access procedure. In some embodiments, the UE receives cell (re)selection information and / or RACH configuration for each slice / slice group / access category / access category group / UE type / service type, and the UE applies the cell (re)selection information and / or RACH configuration during the cell (re)selection and / or random access procedure for a particular 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 network node.

[0034] Exemplary item 1: In operation 102 of Figure 1, the slice-specific cell (re)selection information can 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 group / supported UE type information, and / or reselection priority per UE type / supported service type, and / or reselection priority per service type for intra-frequency / inter-frequency / RAT-inter cell. Such information can be provided via SIB2 / 3 / 4 / 5 or a newly introduced SIB. The corresponding SIB can be configured as an on-demand SIB. All sets or segmentations of cell (re)selection information per slice / slice group / access category / access category group / UE type / service type can be provided in the SIB. 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 can be provided by the SIB can be broadcast to one or more UEs within the transmission range of the cell. · Supported slice / slice group / access category / access category group / UE type / 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. 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 can be indicated to a specific UE via the RRCRelease message. A timer can be configured in the RRCRelease message, and the timer indicates the amount of time when 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 is valid. For example, if the UE determines that the timer received in the RRCRelease message has not expired, the UE can 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 to perform cell (re)selection or RACH as described in this patent document. In another example, if the UE determines that the timer received in the RRCRelease message has expired, the UE can 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 can be broadcast to one or more UEs via the SIB. · Redirection target information for each slice / slice group / access category / access category group / UE type / service type can be indicated in the RRCRelease message. For each of the multiple slices, the redirection target information can indicate the 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, and the timer indicates the amount of time when the redirection target information for each 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 for each slice / slice group / access category / access category group / UE type / service type and perform cell (re)selection or RACH as described in this patent document. In another example, if the UE determines that the timer received in the RRCRelease message has expired, the UE can use the supported slice / slice group / access category / access category group / UE type / service type information that can be broadcast to one or more UEs via SIB, and the reselection priority information for each slice / slice group / access category / access category group / UE type / service type.

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

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

[0037] Exemplary item 2: In operation 104 of FIG. 1, the UE applying 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] Exemplary item 2.1: Use of reselection priorities for each slice / slice group / access category / access category / slice group / access category / access category group / UE type / service type group in system information · If configured, the UE applies the reselection priority corresponding to (or associated with) the first slice in the permitted / requested S-NSSAI or the 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 the common priority. In some embodiments, the common priority includes a default priority that is applicable to one or more (or all) slices. · Example: As shown in Table 1 below, since the UE determines that at least slice number 1 is the first slice, the UE may select and apply the reselection priority for slice number 1 (shown in bold italic text).

Table 1

Table 2

[0039] Exemplary item 2.2: Use of supported slice information in system information (in the case where no specific priority is configured for any slice) · The UE considers (or determines) that the frequency with the maximum number of supported slices overlapping with the permitted / requested S-NSSAI is associated with (or has) the highest priority. · Example: As shown in Table 3 below, since the UE determines that at least F3 has the maximum number of supported slices overlapping with the permitted / requested S-NSSAI, the UE may determine that the frequency F3 (shown in bold italic text) is associated with the highest priority.

Table 3

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[0040] Exemplary Item 2.3: Use of per-slice dedicated reselection priority in the RRC Release message · If configured, the UE applies the dedicated reselection priority corresponding to the first slice in the permitted / requested S-NSSAI. If no reselection priority is configured for the first slice, the UE applies the common dedicated priority. · Example: As shown in Table 6 below, the UE determines that at least slice number 1 is the first slice in the permitted / requested S-NSSAI. Therefore, the UE applies the dedicated reselection priority for slice number 1 (shown in bold italic text).

Table 6

Table 7

[0041] Exemplary Item 2.4: Use of Supported Slice Information in the RRCRelease Message (in the case where no dedicated priority is configured for any slice) · The UE shall consider (or determine) that the frequency with the maximum number of supported slices overlapping with the permitted / requested S-NSSAI is associated with the highest priority. · Example: As shown in Table 8 below, the UE determines that at least F3 has the maximum number of supported slices overlapping with the permitted / requested S-NSSAI, so the UE shall consider (or determine) that the frequency F3 (shown in bold italic text) is associated with the highest priority. Also, F3 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 slice information in the RRCRelease message.

Table 8

Table 9

Table 10

[0042] Exemplary Item 2.5: Use of redirection target information for each slice in the RRCRelease message · If configured, the UE applies the redirection target information corresponding to the first slice in the permitted / requested S-NSSAI. In some embodiments, for each of the plurality of slices, the redirection target information can indicate a frequency as a target for cell (re)selection for the slice. In some embodiments, for each of the plurality of slices, the redirection target information can 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 the common redirection target information. · Example: As shown in Table 11 below, since the UE determines that at least slice number 1 is the first slice in the permitted / requested S-NSSAI, the UE applies the redirection target information configured for slice number 1 (shown in bold italic text).

Table 11

Table 12

[0043] Exemplary item 3: In operation 102 of FIG. 1, the RACH configuration for each slice / slice group / access category / access category group / UE type may include any one or more of the following. · Two-step and / or four-step RACH common and dedicated resources (e.g., RACH occasion (RO) in the frequency and time domains, and / or preamble) for each slice / slice group / access category / access category group / UE type / service type. · The UE type can be a UE with reduced capabilities, or a UE that supports coverage enhancement, or a UE that supports small data transmission, or a UE that initiates small data transmission. · In addition to the existing RACH-ConfigGeneric for each slice / slice group / access category / access category group / specific UE type, a separate RO by prach-ConfigurationIndex / msg1-FDM / msg1-FrequencyStart / msgA-PRACH-ConfigurationIndex / msgA-RO-FDM / msgA-RO-FrequencyStart. · In addition to the existing totalNumberOfRA-Preambles, separate preambles for each slice / slice group / access category / access category group / UE type. ○ Example 1: The ra-PreambleStartIndex and number of preambles to be used for a certain slice / slice group / access category / access category group / UE type. ○ Example 2: The ra-PreambleStartIndex and ra-PreambleEndIndex of the preambles to be used for a certain slice / slice group / access category / access category group / UE type. · When associating the existing preambles with slices / slice groups / access categories / access category groups / UE types, the preambles in the following examples are within the existing totalNumberOfRA-Preambles. ○ Example 1: The ra-PreambleStartIndex and number of preambles to be used for a certain slice / slice group / access category / access category group / UE type. ○ Example 2: The ra-PreambleStartIndex and ra-PreambleEndIndex of the preambles to be used for a certain slice / slice group / access category / access category group / UE type. ·By configuring sliceAssociationPeriod / sliceGroupAssociationPeriod / accessCategoryAssociationPeriod / accessCategoryGroupAssociationPeriod / UEtypeAssociationPeriod / servicetypeAssociationPeriod = N×PRACH association period (N = 1, 2, 3, ···), associate the existing RO with slice / slice group / access category / access category group / UE type / service type. sliceAssociationPeriodIndex / sliceGroupAssociationPeriodIndex / accessCategoryAssociationPeriodIndex / accessCategoryGroupAssociationPeriodIndex / UEtypeAssociationPeriodIndex / servicetypeAssociationPeriodIndex will be configured for each slice / slice group / access category / access category group / UE type. · The ra-PreambleStartIndex and number + sliceAssociationPeriod and sliceAssociationPeriodIndex of the preamble to be used for a certain slice; the ra-PreambleStartIndex and number + sliceGroupAssociationPeriod and sliceGroupAssociationPeriodIndex of the preamble to be used for a certain slice group; the ra-PreambleStartIndex and number + accessCategoryAssociationPeriod and accessCategoryAssociationPeriodIndex of the preamble to be used for a certain access category; the ra-PreambleStartIndex and number + accessCategoryGroupAssociationPeriod and accessCategoryGroupAssociationPeriodIndex of the preamble to be used for a certain access category group; the ra-PreambleStartIndex and number + UETypeAssociationPeriod and UETypeAssociationPeriodIndex of the preamble to be used for a certain UE type; or, the ra-PreambleStartIndex and number + serviceTypeAssociationPeriod and serviceTypeAssociationPeriodIndex of the preamble to be used for a certain service type, to associate existing RO / preambles with slices / slice groups / access categories / access category groups / UE types / service types by constructing them. · A network (NW) such as a base station or an NW device can define a Random Access Channel (RACH) resource identifier (ID) and allocate it to some RACH occasions and / or preambles in the 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. [[ID=S1]] ○ One or more RACH resource IDs can also be configured by the NW for a specific 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 specific service, e.g., configured for small data transmission. ○ The NW can transmit one or more RACH resource IDs in the paging message / paging DCI / short message for each paging record, indicating the RACH resources to be used when the paged UE starts a random access in response to the paging. ○ The RACH resource ID can be explicitly allocated by the NW. Or it can be an index from a RACH resource list. For example, index 0 refers to the first RACH resource in the list, and index 1 refers to the second RACH resource in the list. · A use case indication is provided for each RACH resource (e.g., a RACH occasion and / or preamble in the frequency and / or time domain), indicating whether the RACH resource can be used by a certain UE type / service type / slice / slice group / access category group / access category. The ○ indication can be provided by the NW to the UE in an explicit way 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 refers to a certain 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 a RedCap UE. ○ appliedtoCE ENUMERATED {true}, when set to true, indicates that this RACH resource can be used by a UE that supports 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 can be applied for the first slice in the slice list supported by the RACH resource, the second bit in the bitmap with value 1 indicates that the RACH resource can be applied for the second slice in the slice list supported by the RACH resource, and so on. ○ applied to slice group Bitmap BIT STRING (SIZE (maxNumber of supported slice group)) OPTIONAL. The first bit in the bitmap with value 1 indicates that it can be applied for the first slice group in the slice group list supported by the RACH resource. The second bit in the bitmap with value 1 indicates that it is applied for the second slice group in the slice group list supported by the RACH resource, and so on. ○ applied to access category Bitmap BIT STRING (SIZE (maxNumber of supported access categories)) OPTIONAL. The first bit in the bitmap with value 1 indicates that it can be applied for the first access category in the access category list supported by the RACH resource. The second bit in the bitmap with value 1 indicates that it is applied for the second access category in the access category list supported by the RACH resource, and so on. ○ applied to access category group Bitmap BIT STRING (SIZE (maxNumber of supported access category group)) OPTIONAL. The first bit in the bitmap with value 1 indicates that it can be applied for the first access category group in the access category group list supported by the RACH resource. The second bit in the bitmap with value 1 indicates that it is applied for the second access category group in the access category group list supported by the RACH resource, and so on. ○ The indication can also be provided in an implicit way. For example, some Msg3 repetition related configurations (used by UEs that support coverage enhancement) can be provided together with the RACH resource so that UEs that support coverage enhancement will recognize 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, and 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. In the formula, 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), the subcarrier spacing for determining t_id can be based on the value of μ specified in Clause 5.3.2 of TS 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 configuration 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 the RACH configuration for each slice / slice group / access category / access category group / UE type / service type during the random access procedure, which may include the UE performing any of the following operations in Exemplary Items 4.1 - 4.4.

[0045] Exemplary Item 4.1: RACH Type Selection · For the case where a slice / slice group / access category / access category group / UE type / service type is composed of 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 where a slice / slice group / access category / access category group / UE type / service type is composed of both 2-step and 4-step RACH resources, the UE needs to select from 2-step and 4-step. · If the BWP selected for the random access procedure is composed 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 uses the cell-specific msgA-RSRP-Threshold to select the RACH type. For example, if the RSRP of the downlink path loss criterion exceeds msgA-RSRP-Threshold, set RA_TYPE to 2-step RA. · The UE uses the msgA-RSRP-Threshold configured for this intended slice / slice group / access category / access category group / UE type / service type to select the RACH type.

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

[0047] Exemplary Item 4.3: RACH Priority Parameter Selection ·Regarding the case when both the RACH prioritization parameters for MPS / MCS and the RACH prioritization parameters for the intended slice / slice group / access category / access category group / UE type / service type are configured:

Table 12-1

Table 12-2

[0048] Exemplary Item 4.4: RACH Resource Selection · When selecting the RACH resources used for random access, the UE will consider one or more of the following information: · The intended slice / slice group / access category / access category group · UE type, e.g., a UE with reduced capabilities, or a UE that supports coverage enhancement, or a UE that supports small data transmission, or a UE that initiates small data transmission. · Service type, e.g., small data transmission. · For example, a UE with reduced capabilities attempting to initiate small data transmission in slice number 1 will select the RACH resources applicable for the UE with reduced capabilities, the small data transmission service, and slice number 1. · For example, a UE with a degraded ability attempting to initiate small data transmission at slice number 1 will select a RACH resource applicable to the degraded 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 a slice / slice group / access category / access category group / UE type / service type in the paging message / paging DCI / short message.

[0049] The following sections illustrate several implementation examples. The exemplary 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 exemplary section can be combined with one or more features of another exemplary section. Further, 5G terminology is used for clarity of explanation, but the techniques disclosed in this document are not limited to 5G technology only and can be used in wireless systems implementing other protocols.

[0050] (I. Implementation Example 1:)

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

Table 13

[0052] Supported slice information with or without priorities for slices of intra-frequency cells can be provided in SIB2 as shown by bold italic text in the example given below.

Table 13-1

[0053] Slice information with or without priority for each slice of the inter-frequency cells can be provided in SIB4 as shown by the bold italic text in the examples given below. [Table 13-2] [Table 13-3]

[0054] Slice information with or without priority for each slice of the inter-RAT cells can be provided in SIB5 as shown by the bold italic text in the examples given below. [Table 13-4]

[0055] (II. Implementation Example 2:)

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

[0057] The UE starts Txxx with the value set for txxx and, before Txxx expires, considers the frequency with the highest priority to be associated with the maximum number of supported slices that overlap with the permitted / requested S-NSSAI.

[0058] Slice information with or without per-slice priority for neighboring cells can be provided in an RRC Release message as shown by the bold italic text in the examples given below. [Table 14-1]

[0059] (III. Implementation Example 3:)

[0060] The UE receives a per-slice redirection configuration (as shown in Table 15 below) together with timer txxx in an RRC Release message. [Table 15]

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

[0062] The per-slice redirection configuration can be provided in an RRC Release as shown by the bold italic text in the examples given below. [Table 15-1]

[0063] (IV. Implementation Example 4:)

[0064] The UE receives a two-step CFRA resource or a four-step CFRA resource configured for the intended slice, uses the two-step CFRA resource or the four-step CFRA resource, and after handover, starts a random access to the target cell.

[0065] The per-slice 2-step CFRA resource or 4-step CFRA resource can be provided in the RRCReconfiguration message as shown in bold italic 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] The exemplary techniques described below are for performing cell (re)selection and / or random access using cell (re)selection information provided for each slice in a plurality of slices and / or an RACH configuration. 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] Figure 2 shows an exemplary flowchart for a method 200 of implementing a slice-aware cell selection technique. Operation 202 includes a communication device implementing a cell selection technique using one set of cell selection-related information associated with a slice, where the one set of cell selection-related information is from a plurality of sets of cell selection-related information associated with a plurality of slices, and each set of cell selection-related information is associated with one slice from the plurality of slices.

[0072] In some embodiments of method 200, the communication device selects or determines one set of cell selection-related information associated with a slice from a plurality of sets of cell selection-related information associated with a plurality of slices, and uses the one set of cell selection-related information associated with the slice to implement a cell selection technique, where each set of cell selection-related information is associated with one slice from the plurality of slices.

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

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

[0075] In some embodiments of method 200, the communication device implements a cell selection technique using a cell by using the frequency with the highest priority, where the frequency is associated with the cell and the frequency has the highest priority in response to being supported by the slice that is first in the list of slices in the single network slice selection assistance information (S-NSSAI) for which the frequency is permitted or the requested S-NSSAI. In some embodiments of method 200, the communication device implements a cell selection technique using a cell by using the frequency with the highest priority, where the frequency is associated with the cell and 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 the slice that is first in the list of slices in the single network slice selection assistance information (S-NSSAI) for which the frequency is permitted or the requested S-NSSAI.

[0076] Figure 3 shows an exemplary flowchart of method 300 for implementing a slice recognition random access technique. Operation 302 includes the communication device implementing a random access technique using one set of random access channel (RACH) configurations associated with a slice, where one set of RACH configurations is 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 is associated with one slice from the plurality of slices.

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

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

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

[0080] In some embodiments of method 300, a communication device implements a random access technique by using a first set of RACH prioritization parameters configured for a communication device configured for multimedia priority service (MPS) or mission critical service (MCS), or the communication device implements a random access technique by using a second set of RACH prioritization parameters configured for a slice.

[0081] FIG. 4A shows a flowchart of a method 400 for a network device to provide a plurality of sets of cell selection related information for a plurality of slices for a communication device to implement a slice recognition cell selection technique. Operation 402 includes transmitting, by the network device, 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 one slice from the plurality of slices.

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

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

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

[0085] In some embodiments of 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 one set of RACH configuration associated with the 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 method 410, the message is included in a paging message or paging downlink control information (DCI) or a short message. In some embodiments of method 410, 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 of the multiple slices, the resources including the location of RACH occasions in the frequency domain and time domain, and the resources are common resources associated with multiple communication nodes or dedicated resources allocated to a communication node. In some embodiments of 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 method 410, a plurality of sets of RACH configurations include a first value indicative of a maximum number of permitted failed random access attempts for each slice from a plurality of slices, and a second value indicative of a threshold reference signal received power (RSRP) for each slice from the plurality of slices. In some embodiments of method 410, a plurality of sets of RACH configurations include a first value indicative of a maximum number of permitted failed random access attempts for each slice from a plurality of slices or a second value indicative of a threshold reference signal received power (RSRP) for each slice from the plurality of slices. In some embodiments of method 410, a first transmission comprising a plurality of sets of RACH configurations is performed to a plurality of communication devices comprising communication devices via system information. In some embodiments of method 410, a first transmission comprising a plurality of sets of RACH configurations is performed via radio resource control (RRC) signaling dedicated to a communication device.

[0087] In some embodiments, an apparatus for wireless communication comprises a processor configured to perform the operations recited with respect to method 200-410 and 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 the processor, causes the processor to implement the operations recited with respect to method 200-410 and the embodiments described in this patent document.

[0088] FIG. 5 shows an exemplary 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 configure the hardware platform 500 to perform the operations described in the various embodiments described in FIGS. 1-4B and this patent document when executed by the processor 510. The transmitter 515 transmits or sends information or data to another node. For example, a network node transmitter can send a message to a user equipment. The receiver 520 receives information or data transmitted or sent by another node. For example, a user equipment can receive a message from a network node.

[0089] Implementations such as those discussed above would apply to wireless communications. FIG. 6 shows 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 uses a communication link to the network (sometimes called the uplink direction as depicted by the dashed arrows 631, 632, 633) to access the BS (e.g., the network), which then enables subsequent communication from the BS to the UE (e.g., in the direction from the network to the UE, sometimes called the downlink direction as shown by the arrows 641, 642, 643). In some embodiments, the BS transmits information to the UE (sometimes called the downlink direction as depicted by the arrows 641, 642, 643), which then enables subsequent communication from the UE to the BS (e.g., in the direction from the UE to the BS, sometimes called the uplink direction as shown by the dashed arrows 631, 632, 633). The UE can be, for example, a smartphone, a tablet, a mobile computer, a machine-to-machine (M2M) device, an Internet of Things (IoT) device, etc.

[0090] The UE can be, for example, a smartphone, a tablet, a mobile computer, a machine-to-machine (M2M) device, an Internet of Things (IoT) device, etc.

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

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

[0093] In some embodiments, the cell (re)selection information for each 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 cell (re)selection information for each slice 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 permitted / 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 the reselection priority per slice is configured. · The UE considers (or determines) that the frequency with the maximum number of supported slices overlapping with the permitted / requested S-NSSAI is associated with the highest priority. · The UE considers (or determines) that the frequency supporting the first slice in the permitted / requested S-NSSAI or the frequency supporting 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: · Two-step and / or four-step RACH common and dedicated resources (RACH occasions in the frequency and time domains, and / or preambles) for slice / slice group / access category / access category group / UE type / service type. · Random access prioritization configuration (e.g., powerRampingStepHighPriority and scalingFactorBI) for slice / slice group / access category / access category group / UE type / service type. · 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 the 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 a 2-step or 4-step random access type. · When the UE fails a certain number of times in random access using slice / slice group / access category / access category group / UE type / service type specific RACH resources, it performs 2-step or 4-step using common resources. · When the UE fails a certain number of times in 2-step random access using slice / slice group / access category / access category group / UE type / service type specific RACH resources, it performs 4-step random access using slice / slice group / access category / access category group / UE type / service type specific 4-step RACH resources, and the 4-step random access is performed using the same slice / the same slice group / the same access category / the same access category group / UE type / service type as that used by the 2-step random access. · The UE selects from the RACH prioritization parameters configured for MPS / MCS UEs and the RACH prioritization parameters configured for slice / slice group / access category / access category group / UE type / service type.

[0097] In this document, the term "exemplary" is used to mean "an example of", and does not imply an ideal or preferred embodiment unless otherwise described.

[0098] Some of the embodiments described in this specification 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. Computer-readable media may include removable and non-removable storage devices including, by way of example and not limitation, read only memory (ROM), random access memory (RAM), compact discs (CDs), digital versatile discs (DVDs), etc. Thus, computer-readable media can include non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, etc. 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 the steps of the methods disclosed herein. A particular sequence of such executable instructions or associated data structures represents an example 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 that use hardware circuits, software, or combinations thereof. For example, a hardware circuit implementation can include discrete analog and / or digital components integrated, for example, as part of a printed circuit board. Alternatively, or in addition, 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, in addition, or alternatively, include a digital signal processor (DSP), which is a specialized microprocessor with an architecture optimized for the operational requirements of digital signal processing associated with the functionality disclosed herein. Similarly, the various components or sub-components 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 connectivity methods and media known in the art, including, but not limited to, communication via the Internet, wired, or wireless networks using appropriate protocols.

[0100] This book contains many details, but these should not be construed as limitations on the scope of the claimed invention or what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features described in this book in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, the various features described in the context of a single embodiment can also be implemented separately in multiple embodiments or in any suitable sub-combination. Further, features may be described above as operating in a certain combination and may even be claimed as such initially, but one or more features from the claimed combination can in some cases be deleted from the combination, and the claimed combination can be directed to a sub-combination or a variation of a sub-combination. Similarly, operations are depicted in the drawings in a particular order, but this should not be understood as requiring that such operations be performed in the particular order shown or in a sequential order, or that all of the illustrated operations be performed, in order to achieve a desirable result.

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

Claims

1. A wireless communication method, wherein the wireless communication method comprises a communication device performing a random access technique using one set of a random access channel (RACH) configuration associated with a slice group or a user equipment (UE) type or a service type, wherein the one set of the RACH configuration 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 configuration being associated with one slice group from the plurality of slice groups or the plurality of UE types or the plurality of service types, the random access technique being performed using a common resource or a dedicated resource included in the one set of the RACH configuration, the common resource or the dedicated resource including a preamble start index and a number of preambles to be used for the slice group or the UE type or the service type, each resource from the common resource and the dedicated resource having a use case indication indicating whether the resource is used by the slice group or by the UE type or by the service type. A wireless communication method.

2. The method according to claim 1, wherein the plurality of sets of the RACH configuration includes a random access prioritization configuration indicating a configuration regarding a prioritized random access procedure for each slice group among the plurality of slice groups.

3. The method according to claim 1, wherein the plurality of sets of the RACH configuration includes a value indicating a threshold reference signal received power (RSRP) for each slice group from the plurality of slice groups.

4. The method according to claim 1, wherein 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.

5. The method according to claim 1, wherein the communication device performs the random access technique by using one set of RACH prioritization parameters configured for a slice group.

6. A wireless communication method, The wireless communication method is for a network device to perform a first transmission to a communication device, the first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with a plurality of slice groups or a plurality of user equipment (UE) types or a plurality of service types, each set from the plurality of sets of RACH configurations being associated with one slice group from the plurality of slice groups or the plurality of user equipment (UE) types or the plurality of service types for the network device to receive a random access preamble from the communication device using one set of the RACH configurations associated with one slice group from the plurality of sets of RACH configurations and a common resource or a dedicated resource is included in the one set of the RACH configurations the common resource or the dedicated resource includes a preamble start index and a number of preambles to be used for the slice group or the UE type or the service type each resource from the common resource and the dedicated resource has a use case indication indicating whether the resource is used by the slice group or by the UE type or by the service type, the wireless communication method. **Claim 7** The method according to claim 6, wherein the plurality of sets of the RACH configurations includes a random access prioritization configuration indicating a configuration regarding a prioritized random access procedure for each slice group among the plurality of slice groups. **Claim 8** The method according to claim 6, wherein the plurality of sets of the RACH configurations includes a value indicating a threshold reference signal received power (RSRP) for each slice group from the plurality of slice groups. **Claim 9** An apparatus for wireless communication, comprising a processor configured to implement a method, the method including a communication device performing a random access technique using one set of a random access channel (RACH) configuration associated with a slice group or a user equipment (UE) type or a service type and The one set of the RACH configuration 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 configuration 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 random access technique is executed using a common resource or a dedicated resource included in the one set of the RACH configuration, The common resource or the dedicated resource includes a preamble start index and a number of preambles to be used for the slice group or the UE type or the service type, Each resource from the common resource and the dedicated resource has a use case indication indicating whether the resource is used by the slice group or by the UE type or by the service type, a device.

10. The apparatus according to claim 9, wherein the plurality of sets of the RACH configuration includes a random access prioritization configuration indicating a configuration regarding a prioritized random access procedure for each slice group among the plurality of slice groups.

11. The apparatus according to claim 9, wherein the plurality of sets of the RACH configuration includes a value indicating a threshold reference signal received power (RSRP) for each slice group from the plurality of slice groups.

12. The apparatus according to claim 9, wherein the communication device executes the random access technique by using one set of RACH prioritization parameters configured for a slice group.

13. An apparatus for wireless communication, The apparatus includes a processor configured to implement a method, The method is to perform a first transmission to a communication device, the first transmission comprising a plurality of sets of random access channel (RACH) configurations associated with a plurality of slice groups or a plurality of user equipment (UE) types or a plurality of service types, each set from the plurality of sets of RACH configurations being associated with one slice group from the plurality of slice groups or the plurality of user equipment (UE) types or the plurality of service types, the network device receiving a random access preamble from the communication device using one set of the RACH configurations associated with one slice group from the plurality of sets of RACH configurations comprising, a common resource or a dedicated resource is included in the one set of the RACH configurations, the common resource or the dedicated resource includes a preamble start index and a number of preambles to be used for the slice group or the UE type or the service type, each resource from the common resource and the dedicated resource has a use case indication indicating whether the resource is used by the slice group or by the UE type or by the service type, a device.

14. The apparatus according to claim 13, wherein the plurality of sets of the RACH configurations include a random access prioritization configuration indicating a configuration regarding a prioritized random access procedure for each slice group among the plurality of slice groups.

15. The apparatus according to claim 13, wherein the plurality of sets of the RACH configurations include a value indicating a threshold reference signal received power (RSRP) for each slice group from the plurality of slice groups.

16. The method according to claim 1, wherein the UE type includes a UE with reduced capabilities, a UE supporting coverage enhancement, a UE supporting small data transmission, a UE starting small data transmission.

17. The method according to claim 1, wherein the service type includes small data transmission.

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