Method and apparatus for determining synchronization signal block location in a small bandwidth channel

Abstract

The base station generates a punctured synchronization signal block (SSB) for a channel of the frequency band based on the SSB. The bandwidth of the SSB exceeds the bandwidth of the channel. The punctured SSB includes a punctured physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS). The PSS of the punctured SSB has a center frequency indicated by a synchronization raster position of a set of synchronization raster positions associated with the frequency band. The punctured PBCH is derived from the PBCH of the first SSB based on a puncture pattern associated with the synchronization raster position. The base station transmits the punctured SSB in the channel. A user equipment (UE) detects the punctured SSB according to the synchronization raster position.

Description

[Technical Field]

[0001] [Related Applications] This application claims priority to U.S. Provisional Application No. 63 / 324,988, entitled "Determining Synchronization Burst Locations for Small Bandwidth Channels," filed March 29, 2022, and U.S. Provisional Application No. 63 / 422,679, entitled "Determining Synchronization Burst Locations for Small Bandwidth Channels," filed November 4, 2022. All of the foregoing patent applications are incorporated herein by reference as if reprinted in their entirety.

[0002] [Technical field] FIELD OF THE DISCLOSURE The present disclosure relates generally to wireless communications and, in particular embodiments, to a method and apparatus for determining synchronization block locations for small bandwidth channels. [Background technology]

[0003] A communication network may include a base station having a coverage area and multiple user equipment (UE). The base station may establish uplink and downlink connections with the UE, which are responsible for carrying data from the UE to the base station and from the base station to the UE. The base station may periodically transmit synchronization signal blocks (SSBs). When a UE searches for a base station or cell, for example, when the UE is powered on or in an idle state, or when the UE enters the coverage area of ​​a base station / cell, the UE may use the SSBs to derive information necessary to synchronize with and access the base station / cell. The UE is expected to be able to determine where to detect the SSBs in order to access the base station / cell. Summary of the Invention

[0004] Technical advantages are generally achieved by embodiments of the present disclosure that describe methods and apparatus for determining synchronization signal block locations in a small bandwidth channel.

[0005] According to one aspect of the present disclosure, there is provided a method, comprising: receiving, by a user equipment (UE), from a base station, a punctured synchronization signal block (SSB) in a channel of a frequency band; the punctured SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a punctured physical broadcast channel (PBCH) derived from a first PBCH of a first SSB by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronous raster position; detecting, by the UE, the punctured SSB according to the first synchronization raster position; A method is provided which includes:

[0006] Optionally, in any of the aforementioned aspects, the punctured SSB has a bandwidth no greater than a bandwidth of the channel, and the first SSB has a bandwidth greater than a bandwidth of the channel.

[0007] Optionally, in any of the preceding aspects, the difference between the bandwidth of the first SSB and the bandwidth of the punctured SSB is related to the second number of RBs transmitted.

[0008] Optionally, in any of the aforementioned aspects, the method further includes determining, by the UE, attributes of the channel based on the received punctured PBCH in the punctured SSB, wherein the attributes include a starting frequency location of the channel.

[0009] Optionally, in any of the preceding aspects, determining the channel attributes comprises: The method includes determining, by the UE, a starting frequency location of the channel based on the received punctured PBCH, a center frequency of a PSS of the punctured SSB, and the first puncture pattern.

[0010] Optionally, in any of the preceding aspects, determining the channel attributes comprises: The method includes determining, by the UE, a starting frequency position of the channel based on the received punctured PBCH, the frequency positions of RBs occupied by the PSS of the punctured SSB, and an offset relative to the frequency positions of the RBs.

[0011] Optionally, in any of the aforementioned aspects, the PSS of the first SSB has a center frequency indicated by a second synchronization raster position of the second set of synchronization raster positions.

[0012] Optionally, in any of the aforementioned aspects, the frequency of the first set of synchronized raster positions is based on a first raster interval and a first set of shift intervals, and the frequency of the second set of synchronized raster positions is based on a second raster interval and a second set of shift intervals.

[0013] Optionally, in any of the preceding aspects, the first raster interval is different from the second raster interval, and the first raster interval is related to a channel raster position of the channel.

[0014] Optionally, in any of the preceding aspects, the second raster spacing is a multiple of the first raster spacing.

[0015] Optionally, in any of the preceding embodiments, one or more shift intervals of the first set of shift intervals are different from one or more shift intervals of the second set of shift intervals.

[0016] Optionally, in any of the preceding aspects, the first set of synchronous raster positions is obtained by shifting the second set of synchronous raster positions in the frequency domain.

[0017] Optionally, in any of the preceding aspects, the channel has a bandwidth of 5 MHz or less.

[0018] Optionally, in any of the preceding aspects, the frequency span of the first SSB is 20 RBs.

[0019] Optionally, in any of the aforementioned aspects, the first set of synchronization raster positions includes a third synchronization raster position associated with a second puncture pattern.

[0020] According to another aspect of the present disclosure, there is provided a method, comprising: generating, by the base station, a punctured synchronization signal block (SSB) for a channel of the frequency band based on a first synchronization signal block (SSB) having a first bandwidth that exceeds a second bandwidth of the channel; The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH obtained from a first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronous raster position; transmitting, by the base station, the punctured SSB on the channel; A method is provided which includes:

[0021] Optionally, in any of the preceding aspects, the punctured SSB has a third bandwidth no greater than the second bandwidth of the channel.

[0022] Optionally, in any of the preceding aspects, a difference between a first bandwidth of the first SSB and a third bandwidth of the punctured SSB is associated with the second number of RBs transmitted.

[0023] Optionally, in any of the aforementioned aspects, the punctured PBCH includes information indicative of attributes of the channel, the attributes including a starting frequency location of the channel.

[0024] Optionally, in any of the aforementioned aspects, the starting frequency location of the channel can be determined based on the punctured PBCH, a center frequency of the PSS of the punctured SSB, and the first puncture pattern.

[0025] Optionally, in any of the aforementioned aspects, the starting frequency location of the channel can be determined based on the punctured PBCH, the frequency location of an RB occupied by the PSS of the punctured SSB, and an offset relative to the frequency location of the RB.

[0026] Optionally, in any of the aforementioned aspects, the PSS of the first SSB has a center frequency indicated by a second synchronization raster position of the second set of synchronization raster positions.

[0027] Optionally, in any of the aforementioned aspects, the frequency of the first set of synchronized raster positions is based on a first raster interval and a first set of shift intervals, and the frequency of the second set of synchronized raster positions is based on a second raster interval and a second set of shift intervals.

[0028] Optionally, in any of the preceding aspects, the first raster interval is different from the second raster interval, and the first raster interval is related to a channel raster position of the channel.

[0029] Optionally, in any of the preceding aspects, the second raster spacing is a multiple of the first raster spacing.

[0030] Optionally, in any of the preceding embodiments, one or more shift intervals of the first set of shift intervals are different from one or more shift intervals of the second set of shift intervals.

[0031] Optionally, in any of the preceding aspects, the first set of synchronous raster positions is obtained by shifting the second set of synchronous raster positions in the frequency domain.

[0032] Optionally, in any of the preceding aspects, the second bandwidth of the channel is less than or equal to 5 MHz.

[0033] Optionally, in any of the preceding aspects, the frequency span of the first SSB is 20 RBs.

[0034] Optionally, in any of the aforementioned aspects, the first set of synchronization raster positions includes a third synchronization raster position associated with a second puncture pattern.

[0035] According to another aspect of the present disclosure, there is provided an apparatus comprising: a non-transitory memory store containing instructions; one or more processors in communication with the memory storage, the instructions, when executed by the one or more processors, optionally causing the device to perform a method as described in any of the preceding aspects; An apparatus is provided that includes:

[0036] According to another aspect of the present disclosure, a non-transitory computer-readable medium is provided, the non-transitory computer-readable medium storing computer instructions that, when executed by one or more processors, cause the one or more processors to perform a method according to any of the preceding aspects.

[0037] According to another aspect of the present disclosure, there is provided a system including a base station (BS) and a user equipment (UE) communicating with the base station, wherein the BS: generating a punctured synchronization signal block (SSB) for a channel of the frequency band based on a first synchronization signal block (SSB) having a first bandwidth exceeding a second bandwidth of the channel; The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH of a first PBCH obtained from the first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronization raster position; and transmitting the punctured SSB on the channel; The UE is configured to: receiving the punctured SSB on the channel; detecting the punctured SSB according to the first synchronization raster position; is configured to execute

[0038] According to another aspect of the present disclosure, there is provided an apparatus comprising: 1. A receiver module configured to receive, from a base station, a punctured primary synchronization signal block (SSB) for a channel of a frequency band, the receiver module comprising: The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH derived from the first PBCH by applying a first puncturing pattern that reduces a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; the PSS of the punctured SSB has a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions configured for the frequency band; a receiver module, wherein the first puncture pattern is associated with the first synchronization raster position; The apparatus further includes a detection module configured to detect the punctured SSB according to the first synchronization raster position.

[0039] According to another aspect of the present disclosure, there is provided an apparatus comprising: a generating module configured to generate a punctured synchronization signal block (SSB) of a channel of a frequency band based on a first synchronization signal block (SSB) having a first bandwidth exceeding a second bandwidth of the channel, The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes a punctured PBCH, the PSS, and the SSS of a first PBCH, the punctured PBCH being derived from the first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; a generating module, wherein the first puncture pattern is associated with the first synchronization raster position; An apparatus is provided that includes: the apparatus further includes a transmitter module configured to transmit the punctured SSB on the channel.

[0040] Aspects of the present disclosure enable communication of synchronization signal blocks in channels having a small bandwidth, for example, a bandwidth of 5 MHz or less, and enable support of wireless communication for devices operating in small bandwidths. [Brief explanation of the drawings]

[0041] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0042] [Figure 1] FIG. 1 is a diagram of an exemplary communication system.

[0043] [Figure 2] FIG. 1 is a diagram of an example resource grid.

[0044] [Figure 3] FIG. 1 is a diagram of an exemplary relationship between a GSCN and an ARFCN.

[0045] [Figure 4] 1 is a diagram showing an example of the location of SSBs in a channel.

[0046] [Figure 5] 10A-10C illustrate examples of notations used to analyze synchronous raster positions within a channel according to embodiments of the present disclosure.

[0047] [Figure 6] 10A-10C illustrate examples of notations used in another analysis of synchronization raster positions with offsets according to embodiments of the present disclosure.

[0048] [Figure 7] 10A-10C illustrate examples of notations used in further analysis of synchronization raster positions with offsets according to embodiments of the present disclosure.

[0049] [Figure 8] FIG. 10 illustrates an example of truncation of an SSB according to an embodiment of the present disclosure.

[0050] [Figure 9] FIG. 10 illustrates another example of truncation of an SSB according to an embodiment of the present disclosure.

[0051] [Figure 10A] FIG. 10 illustrates a further example of truncation of SSB according to an embodiment of the present disclosure. [Figure 10B] FIG. 10 illustrates a further example of truncation of SSB according to an embodiment of the present disclosure.

[0052] [Figure 11] FIG. 1 illustrates an embodiment of a truncated SSB.

[0053] [Figure 12] FIG. 10 is a diagram showing an example of the notation used for truncation of SSB.

[0054] [Figure 13] 1 is a flowchart of an embodiment of the operation for detecting SSB in a channel.

[0055] [Figure 14]1 illustrates an example of an alternative channel for transmitting SSBs according to an embodiment of the present disclosure.

[0056] [Figure 15] 10A-10C illustrate examples of alternative raster positions for SSBs within a channel according to an embodiment of the present disclosure.

[0057] [Figure 16] 10 is a flowchart illustrating an example operation for SSB detection by a UE according to an embodiment of the present disclosure.

[0058] [Figure 17] 10 is another flowchart of an example operation for SSB detection by a UE according to an embodiment of the present disclosure.

[0059] [Figure 18] FIG. 10 illustrates an example of the locations of SSBs and CORESET#0 in a time-frequency grid according to an embodiment of the present disclosure.

[0060] [Figure 19] FIG. 10 is a diagram of an example operation by a UE to determine the location of an SSB according to an embodiment of the present disclosure.

[0061] [Figure 20] 1 is a flowchart of an embodiment method for SSB communication.

[0062] [Figure 21] 10 is a flowchart of another embodiment method for SSB communication.

[0063] [Figure 22] FIG. 1 is a diagram of a communication system according to an embodiment.

[0064] [Figure 23A] FIG. 2 is a diagram of a terminal device (ED) according to an embodiment.

[0065] [Figure 23B]FIG. 2 is a diagram of a base station according to an embodiment.

[0066] [Figure 24] FIG. 1 is a block diagram of an embodiment of a computing system.

[0067] Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate relevant aspects of the embodiments and are not necessarily drawn to scale. DETAILED DESCRIPTION OF THE INVENTION

[0068] The making and using of embodiments of the present disclosure are described in detail below. However, it should be understood that the concepts disclosed herein can be embodied in a wide variety of specific contexts, and that the specific embodiments described herein are merely exemplary and do not limit the scope of the claims. Furthermore, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the spirit and scope of the present disclosure, as defined by the appended claims.

[0069] FIG. 1 is a diagram of an exemplary communication system 100. The communication system 100 includes an access node (AN) 110 within a coverage area 101 that serves user equipment (UE) such as a UE 120. In a first mode of operation, communication with the UE 120 is routed through the access node 110 having the coverage area 101. The access node 110 is connected to a backhaul network 115 for connectivity to the Internet, operations management, and the like. In a second mode of operation, communication with the UE 120 does not route through the access node 110, but the access node 110 typically allocates resources used by the UE 120 for communication when certain conditions are met. Communication between a pair of UEs 120 can use a sidelink connection (shown as two independent unidirectional connections 125). In FIG. 1, sidelink communication occurs between two UEs 120 operating within the coverage area 101. However, sidelink communication may generally occur when two UEs 120 are both outside the coverage area 101, both within the coverage area 101, or one UE is within the coverage area 101 and the other UE is outside the coverage area. Communication between a UE-access node pair is via a unidirectional communication link, with the communication link from the UE to the access node being referred to as the uplink 130 and the communication link from the access node to the UE being referred to as the downlink 135.

[0070] An access node is also commonly referred to as an access point, Node B, evolved Node B (eNB), next generation (NG) Node B (gNB), master eNB (MeNB), secondary eNB (SeNB), master gNB (MgNB), secondary gNB (SgNB), network controller, control node, base station, access point, transmission point (TP), transmission-reception point (TRP), cell, carrier, macrocell, femtocell, picocell, etc. A UE may also be commonly referred to as a mobile station, mobile, terminal, terminal equipment, user, subscriber, station, etc. The access nodes may provide wireless access in accordance with one or more wireless communication protocols, e.g., Third Generation Partnership Project (3GPP) Long Term Evolution (LTE), LTE advanced (LTE-A), 5G, 5G LTE, 5G NR, sixth generation (6G), High Speed ​​Packet Access (HSPA), IEEE 802.11 family of standards, e.g., 802.11a / b / g / n / ac / ad / ax / ay / be, etc. A communication system may employ multiple access nodes capable of communicating with multiple UEs; however, for simplicity, only one access node and two UEs are shown in FIG. 1 .

[0071] Signals are communicated using time and frequency resources. These can be allocated in units of physical resource blocks (PRBs). In NR mobile broadband (MBB) communications, within a slot, each PRB in the resource grid is defined as a span of 14 consecutive orthogonal frequency division multiplexed (OFDM) symbols in the time domain and 12 consecutive subcarriers in the frequency domain. That is, each PRB contains 12 × 14 resource elements (REs). Each RE is mapped to one OFDM symbol in the time domain and one subcarrier in the frequency domain. When used as a frequency-domain unit, a PRB is 12 consecutive subcarriers. When a normal cyclic prefix is ​​used, there are 14 symbols in a slot, and when an extended cyclic prefix is ​​used, there are 12 symbols in a slot. The duration of a symbol is inversely proportional to the subcarrier spacing (SCS). For SCSs of {15, 30, 60, 120} kHz, the duration of each slot is {1, 0.5, 0.25, 0.125} ms, respectively. Each PRB can be assigned to a control channel, a shared channel, a feedback channel, a reference signal, and / or any combination thereof. Furthermore, some REs of a PRB can be reserved. A similar structure can be used in the sidelink (SL). Communication resources include a PRB, a set of PRBs, a code (similar to that for the physical uplink control channel (PUCCH) when code division multiple access (CDMA) is used), a physical sequence, and a set of REs.

[0072] When a user equipment (UE) in RRC_IDLE state attempts to discover a base station, the UE first searches for synchronization signal blocks (SSBs) transmitted by the base station. The SSBs can include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH) (which includes a master information block (MIB)). From the MIB, the initial downlink bandwidth part (DL BWP) can be established, and parameters for establishing CORESET#0 can also be obtained, which are used to configure resources used for the physical downlink control channel (PDCCH) (which carries downlink control information (DCI)). The DCI can schedule resources for the physical downlink shared channel (PDSCH). The PDSCH can carry a system information block (SIB). SSB allows the UE to synchronize with the base station and establish a connection with the base station for communication.

[0073] 2 is a diagram of an example resource grid 200 including 25 RBs (numbered 0 through 24) in the frequency domain and 14 symbols (numbered 0 through 13) in the time domain. Figure 2 shows that an SSB can occupy 20 RBs (shaded boxes) in frequency (e.g., RB2 through RB21) and span four symbols (e.g., symbols 2 through 5). The center of the SSB (e.g., at RE#0 of RB#12) does not necessarily need to be aligned with RE#0 of the RB.

[0074] In the frequency domain, an SSB is typically centered at one of a predefined set of frequency locations. This set of frequency locations (or frequencies), also known as a synchronization (sync) raster, provides a list of possible SSB center frequencies. Each entry in the synchronization raster represents a frequency (location) at which an SSB can be centered. In the following description, the terms "synchronization raster," "synchronization raster location," "raster location," and "raster point" are used interchangeably. An example set of synchronization raster locations is shown in Table 1 below. Table 1 shows a partial set from Table 5.4.3.3-1 of 3GPP TS38.104, "NR; Base Station (BS) radio transmission and reception," which is incorporated herein by reference in its entirety, with band n1 defined in Table 5.2-1 of 3GPP TS38.104. As an example, if a UE is capable of operating in band n1, Table 1 indicates that the SCS of an SSB transmitted in that band n1 is 15 kHz. The time location of the SSB is shown by "Case A," which corresponds to the timing in clause 4 of TS 38.213, "NR; Physical layer procedures for control," which is incorporated herein by reference in its entirety. The possible frequency locations of the SSB for the band are given by the global synchronization channel number (GSCN). The GSCN can be mapped to frequency using the relationship shown in Table 2 below, or converted to a new radio (NR) absolute radio frequency channel number (ARFCN) using the relationship shown in Table 3 below. As shown in Table 1, the first GSCN in the band is 5279, and subsequent locations are offset from the previous location. <1> The last position is 5419. The offset can be an integer greater than 0.

[0075] For a band, the possible frequency locations given by the GSCN depend on the SSB guard band, the minimum channel bandwidth of the channels within that band, and the SCS. Note that a band can support one or more channels. For example, band n1 spans 60 MHz in the downlink (2110-2170 MHz). There are many combinations of channels deployed by network operators in band n1, such as 5, 10, 15, 20, 25, 30, 40, 50, and 60 MHz channels. If an operator has a license to use 30 MHz in band n1, it can deploy channel combinations such as (5, 5, 5, 15) MHz, (30) MHz, and (25, 5) MHz. In general, the synchronization raster for any band is independent of the channelization within the band (outside of the band's guard band considerations). In general, standards can define a GSCN range for each band. Within a band, one or more channels can be defined. For a particular channel within a band, a subset of this range of GSCNs must be determined. For example, for a 10 MHz channel starting at 2110 MHz, the SSB can be placed at a GSCN value of 5279 instead of 5419. In some unlicensed bands, one GSCN is selected per 20 MHz subchannel. From the UE's perspective, the UE may have prior knowledge of the location of previously used synchronization rasters. However, in general, the UE has minimal knowledge of the band's channelization.

[0076] For Frequency Range 1 (FR1) (frequencies below approximately 7.125 GHz), the set of SCSs available for SSB is 15 kHz and 30 kHz. For Frequency Range 2 (FR2) (frequencies above approximately 24.25 GHz), the set of SCSs available for SSB is 120 kHz and 240 kHz. Recently, a new band, FR2-2 (frequencies above approximately 60 GHz), was agreed upon, using 480 kHz and 960 kHz. [Table 1] Relationship between frequency bands and GSCN (part of Table 5.4.3.3-1 of TS38.104) [Table 1]

[0077] One advantage of the GSCN is that it represents a smaller set of ARFCNs: for example, 15 bits can be used to represent a GSCN, while an ARFCN requires 22 bits. [Table 2] Relationship between frequency and GSCN [Table 2]

[0078] Table 5.4.3.1-1 of TS38.104 includes a note for sub-3 GHz that states, "The default value for operating bands that support only SCS-spaced channel rasters is M=3." [Table 3] Acquisition of ARFCN from GSCN [Table 3]

[0079] For illustrative purposes, Figure 3 is a diagram 300 showing how the gth GSCN value relates to the ath ARFCN value. As shown, the (g+1)th GSCN value is related to the (a+20)th ARFCN value, with 20 being the step size used as an example. Note that based on Table 3, the step size is 20 or 200 (depending on M and N) between consecutive GSCN values ​​for frequencies below 3 GHz. For frequencies above 24.25 GHz, the step size is 288.

[0080] ARFCN(N REF ) to get the frequency in MHz, you can use the following formula:

number

[0081] In NR, the possible frequency locations of an SSB for initial access are controlled by a synchronization raster. The procedure for calculating the set of allowed synchronization raster locations within a band is described in Section 4.3.1.5 of TR38.817-01, which is incorporated by reference in its entirety. For a given channel within a band, it is assumed that there is at least one valid synchronization raster location within that channel. A valid synchronization raster location within a channel is one where the SSB is completely contained within the channel bandwidth and the frequency center of the SSB is at a predefined synchronization raster location.

[0082] Analysis has shown that under certain conditions, the above assumption (i.e., that a given channel has at least one valid synchronization raster position) may not hold. For any given channel, there may be multiple synchronization raster positions that the network can use to transmit SSB. However, taking into account guard bands, the channel bandwidth, and the SSB bandwidth, it may not be possible to find a synchronization raster position within the channel that completely contains the SSB and whose center is on the synchronization raster.

[0083] To illustrate this situation, suppose SSB is transmitted on a 5 MHz channel, an SCS with Δf = 15 kHz is used for SSB, and the synchronization raster spacing (the distance between two adjacent synchronization raster positions) is ΔF raster Consider the case where the SSB bandwidth is 1.2MHz (sub-3GHz). SSB is given by:

number

[0084] As mentioned above, if an SSB (occupying 20 RBs) is completely contained within the channel bandwidth and centered on a predetermined synchronization raster, then there is a valid synchronization raster for the SSB within the channel, and the SSB can be placed within the channel for transmission. A valid SSB position is a synchronization raster position within the channel where the span of the SSB is located. Thus, using FIG. 4 as an example, a valid synchronization raster position places the SSB between the centers of the two SSBs 406 and 408. In other words, a valid synchronization raster position is between the dashed lines 402 and 404 in FIG. 4. The problem is that among the allowable synchronization raster positions within a channel, there may not be a synchronization raster position that satisfies the placement of the SSB within that channel. If the distance (in frequency) between the two lines 402 and 404 is equal to or greater than the raster interval, there will always be at least one valid synchronization raster position within the channel. If the distance (in frequency) is less than the raster interval, there may be a valid synchronization raster position within the channel, but sometimes there may not be a valid synchronization raster position within the channel. The conditions under which no valid sync raster position exists can be determined.

[0085] Considering the difference between the channel bandwidth (5 MHz) and the SSB bandwidth (4100 kHz), the difference of 900 kHz is smaller than the synchronization raster interval of 1.2 MHz (1200 kHz). At this raster granularity, there appears to be a 25% chance of not being able to find a synchronization raster position that meets the requirements for placing SSB on the channel. In this case, the 25% value is based on (1 - 900 kHz / 1200 kHz) and on the assumption that the channels are uniformly distributed in (start frequency) position. Note that analysis may improve that value.

[0086] Two problems can arise: · Whether there is a condition that can be used to determine when there is no valid sync raster position for a channel, based on the current set of GSCNs for the channels in the band. ·How to place the SSB on a channel so that the UE can detect it when there is no valid synchronization raster position for that channel.

[0087] While these are general problems, the solutions have various applications. As described in RP-213603, they can be applied to Reduced complexity (RedCap) UEs that can only support 5 MHz channels, and define the synchronization raster position in the Rel-18 work item description (WID) in "NR support for dedicated spectrum less than 5 MHz for FR1." This is also a general problem for smaller bandwidth channels and possible enhancements for RedCap UEs.

[0088] It also applies to irregular channel bandwidths. In NR, FR1 channel bandwidths are 5, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, and 100 MHz. Note that with 15 kHz SCS spacing, channel bandwidths of 60, 70, 80, 90, and 100 MHz are not permitted because the fast Fourier transform (FFT) exceeds 4096 points. Some operators are considering how to deploy NR channels where there are 7 or 12 MHz channels and channels smaller than 5 MHz.

[0089] The following analysis is for a general synchronous raster spacing scenario considering consecutive synchronous raster positions. To simplify the equations, the sub-3 GHz 50, 150, and 250 kHz offsets (Table 2, corresponding to M=1, 3, 5) are omitted. Initially, the offset is assumed to be 0. After the basic equations / concepts are developed, the equations with offsets are presented.

[0090] Since the synchronization raster indicates the center of the SSB, the first possible position of the synchronization raster within the channel that may be indicated by n0 satisfies:

number

number

[0091] n0 is the first instance of N in a channel when the frequency location of the synchronization raster is obtained using the formula in Table 2 (e.g., N x 1200 kHz + M x 50 kHz). Similarly, n0 can be used to represent the first possible frequency location of the synchronization raster in a channel. L represents the lowest frequency of the channel. The number n0 may be positive. The term (△F raster -f L mod△F raster) represents the difference between the low edge of the channel and the sync raster position. A channel can be specified by a center frequency and a bandwidth, by a low-end frequency (also called the low edge) and a high-end frequency (also called the high frequency or edge), or by a low-end frequency and a bandwidth. The bandwidth is the difference between the high-end and low-end frequencies, and the center frequency is the average of the high-end and low-end frequencies. The low / high edges of a channel are sometimes called the channel bottom / top.

[0092] Similarly, the last possible synchronous raster position n1 in a channel satisfies:

number

number

[0093] Figure 5 is a diagram 500 illustrating the notation used in the above analysis. The first (lowest) possible center frequency of an SSB in a channel is sync raster position 512, and the last (highest) possible center frequency of an SSB in a channel is sync raster position 514. Note that the sync raster position used for the SSB can be anywhere within the channel, such as the center of the channel. As shown in Figure 5, in wider bands, the sync raster position used for the SSB can be near either end of the channel.

[0094] Therefore, to always have at least one synchronous raster position in a channel, the following condition (7) must be met (combining (4) and (6)):

number

number

[0095] Therefore, according to condition (8), the difference between the channel and the SSB bandwidth needs to be larger than the raster interval in order to ensure that there is at least one valid synchronization raster position within the channel.

[0096] Assuming a uniform random distribution of the lower end of the channel between two consecutive raster positions, the probability of not being able to find a valid position is as follows:

Number

[0097] The condition that there is no valid position within the channel is when n1 < n0, or

Number

[0098] Condition (10) is a check that can be performed when condition (8) is not satisfied to determine whether there is a valid synchronization raster position within the channel. Condition (10) solves one of the problems to be solved.

[0099] The above analysis can be extended to determine the sub-3 GHz formula. For sub-3 GHz, there are two sets of offsets. The first set of offsets includes an offset of 150 kHz (corresponding to M = 3) from a 1.2 MHz raster interval, and the second set of offsets includes offsets of {50, 150, 250} kHz from a 1.2 MHz raster interval. Table 5.4.3.1-1 of TS38.104 and the notes described after Table 2 above imply that the band may support only M = 3 (150 kHz).

[0100] Figure 6 is Figure 600 showing the notation used for the following analysis using the first set of offsets.

[0101] The first possible positions n0 and m0 of the synchronization raster within the channel are given by the following equations.

Number

Number

[0102] Similarly, the last possible synchronization raster position n1 and m1 = 3 (corresponding to m1' = 1) within the channel are as follows.

Number

Number

[0103] The condition that there is no valid synchronization raster position within the channel is n1 < n0 or the following:

Number

[0104] As an example, for BW chan = 5 MHz, △F raster = 1200 kHz, BW SSB = 4100 kHz, △F shift = 50 kHz, and m0 = m1 = 3, the condition that there is no valid position within the channel is as follows.

Number

[0105] FIG. 7 is FIG. 700 showing the notation used for the following analysis using the second set of offsets, i.e., sub-3 GHz and {50, 150, 250} kHz offsets from a 1.2 MHz raster spacing.

[0106] m i'={0, 1, 2} is m for i=0, 1. i Note that these correspond to = 1, 3, and 5. To handle the three possible values ​​of m0, we can use the following condition to first find n0:

number

number

[0107] Once n0 is determined, we obtain:

number

[0108] Similar to the analysis of n1 and m1 above, we obtain:

number

number

[0109] Once n1 is determined, we obtain:

number

[0110] There is no valid position in the channel if:

number

[0111] For example, BW chan =5MHz, △F raster =1200kHz, BW SSB =4100kHz, △F shift = 50 kHz, and mmax =5, m min If =1, the conditions for no valid position in the channel are:

number

[0112] Combining (10), (16), and (24), the "probability of not being able to find a valid sync raster position in a channel" is shown in the last column of Table 4 below. This probability assumes that the low end of the channel is on a given frequency. Note that the low end (or equivalently, the center frequency) of a channel is usually on a distinct set of frequencies. [Table 4] Conditions when there is no valid synchronous raster position [Table 4]

[0113] To illustrate, consider a 5 MHz channelization of band n1 with the first channel at 2110 MHz. The check calculation is f L mod△F raster and f L and △F raster is in kHz and the check for valid sync raster position is 500 from Table 4 <f L mod△F raster <800 (M=3), and 600 <f L mod△F raster <700 (M=1, 3, 5). That is, to check whether there is a valid synchronization raster position in the channel of band n1, f L mod△F raster The value of is calculated and 500 <f L mod△F raster <800 (M=3) and 600 <f L mod△F raster <700 (M=1, 3, 5). Table 5 below shows valid synchronization raster positions for this band, assuming 5 MHz channels are stacked starting from the lowest frequency of the band (e.g., f Lchan =f L band +5000k, where the lowest frequency of the channel in kHz (i.e., f L chan ) is the lowest frequency in the band (i.e., f L band ) to 5000 kHz (5 MHz) in multiples k. In Table 5, an "N" (third column) indicates that the check calculation shows that the corresponding channel (starting from the frequency in the first column) does not have a valid SSB synchronization raster. A "Y" in the third or fourth column indicates that the channel has at least one valid SSB synchronization raster position. [Table 5] Example of 5MHz channelization for band n1 [Table 5]

[0114] As a check on this calculation, Table 6 shows potential synchronization raster positions for band n1 in the frequency range 2115 MHz to 2120 MHz. The columns are calculated using the following formula:

number

[0115] For channels with frequencies between 3 GHz and 7 GHz, the set of allowable synchronization raster positions is currently based on the 30 kHz SCS for SSB. Note that the 30 kHz SCS is not a criterion for when there are no valid raster positions. As an illustrative example, assume that a 15 kHz SCS is used for SSB and band n48 (3550-3700 MHz) is considered. Band n48 supports 5 MHz channelization. Next, based on the calculations and checks in Table 4, Table 7 below is generated. In Table 7, an "N" indicates that the corresponding channel (starting with the frequency in the first column) does not have a valid synchronization raster for SSB. A "Y" indicates that the channel has at least one valid synchronization raster position for SSB. [Table 7] Example of virtual 5MHz channelization for band n48 and 15kHz SCS [Table 7]

[0116] The analysis can be extended to consider discrete onset (lower end) frequencies using the following relationship:

number

[0117] Note that 100n mod 1200={0,100,...,1100}, 200n mod 1200={0,200,...,1000}, 500n mod 1200={0,100,...,1100}, 1000n mod 1200={0,200,...,1000}, 2000n mod 1200={0,400,800}, and 5000n mod 1200={0,200,...,1000}.

[0118] In Table 5, for channels whose start locations (start frequencies, low end) are multiples of 5 MHz, the pattern is that one of six consecutive start locations, i.e., one channel out of every six channels that each start at six consecutive start locations, does not have a valid sync raster location. In the hypothetical example of Table 7, 11 of the 30 start frequencies do not have a valid sync raster location, which corresponds to the expected 14 of 36 in Table 8.

[0119] When a channel does not have a valid synchronization raster position, two aspects need to be considered: network deployment and UE behavior. The UE is typically unaware of the channelization used by the network before receiving the SSB.

[0120] Number of RBs in the channel In some embodiments, using equation (2), the number of SSB RBs that can fit into the channel can be calculated for several bandwidths, assuming a 15 kHz SCS and a 5 MHz channel guard band is used. The UE is assumed to reuse the smallest filter. In LTE, a 3 MHz channel can support 15 RBs, which is more than calculated in Table 9 below. The guard band is smaller in LTE. Table 9 shows example numbers of SSB RBs calculated for various bandwidths using a 242.5 kHz guard band and a 15 kHz SCS. Fractional RBs are not allowed in this example (only the integer portion is considered; for example, if the calculated number of RBs is 13.89, it is truncated to 13). [Table 9] Number of RBs assuming a 242.5 kHz guard band and a 15 kHz SCS. Fractional RBs are not allowed (only the integer part is considered, e.g., 13.89 → 13). [Table 9]

[0121] Reusing existing synchronous rasters 1. No solution needed If the condition for no valid synchronization raster position case is not met, the current synchronization raster position is valid for the channel, and no changes to the network deployment or UE behavior are required.

[0122] 2. Truncated SSB If the condition for the no valid raster position case is met, in some embodiments, the network may transmit a truncated SSB. For example, for FR1 and 1200 kHz raster spacing, the network may transmit a subset of 20 RB SSBs as shown in FIG. 8. FIG. 8 illustrates an example of an SSB and its truncation based on the synchronization raster position within the channel. In FIG. 8, box 812 represents the PSS (occupying 10 RBs), box 814 represents the SSS (occupying 10 RBs), and box 816 represents the PBCH. In this example, the number of RBs within the channel is 25 RBs (dotted and white boxes), and the number of RBs in CORESET#0 is 24 RBs (dotted box). The 24 RBs are the initial downlink BWP used for initial access, and the white boxes are RBs not used during initial access. Note that using 10 RBs for the PSS and SSS is merely an example to explain alignment with the center of the SSB. The SSS and PSS each occupy 127 REs, which is slightly more than 10 RBs. With a total of 8 + 9 null subcarriers surrounding the SSS / PSS (null subcarriers (e.g., unoccupied subcarriers) are REs with complex values ​​of 0), 144 REs equals 12 RBs. Box 818 represents an unoccupied RB. While Figure 8 shows the synchronization raster aligned with the RB used for CORESET (RE#0 is aligned), this is not required. Diagram 800 in Figure 8 shows a regular SSB (unatruncate) with a PSS for symbol #2, an SSS for symbol #4, and a PBCH. In the frequency domain, the start of the bandwidth part (BWP) containing CORESET#0 is based on an offset from the start of the SSB. The center 804 of the SSB in diagram 800 is on RE#0 of RB12. The start of the SSB is RE#0 of RB2. The start of the BWP containing CORESET#0 (initial DL BWP) is 2 RBs lower in frequency than the start of the SSB, which corresponds to the start of this BWP having a 2 RB offset in Table 11 below. For a 20 RB SSB, the second and fourth symbols of the SSB have 20 RBs for the PBCH.In the third symbol, the lower (frequency) 4 RBs and the upper 4 RBs are used for the PBCH.

[0123] Diagram 800 shows a channel (e.g., 5 MHz) with a synchronization raster position indicated by 804, with the SSB centered at synchronization raster position 804 in the frequency domain. In diagram 800, the SSB (20 RBs) at synchronization raster position 804 can be completely contained within the channel (24 or 25 RBs). Diagram 820 of FIG. 8 shows a channel with a synchronization raster located at 806. To center the SSB at synchronization raster position 806, the SSB is truncated in the frequency domain. In diagram 820, synchronization raster position 806 (compared to synchronization raster 804) is 3 RBs higher in frequency. Because the entire 20-RB SSB would not be completely contained within the channel (24 or 25 RBs) when centered at 806, the SSB is truncated (punctured). This truncated SSB has 19 RBs, a total of 3 fewer RBs for the PBCH. Note that more RBs can be truncated. As diagram 820 shows, for a 24-RB initial DL BWP (less than 25 RBs), only 18 RBs for the SSB are included in the initial DL BWP. Note that in this example, the RBs containing the SSS and PSS are not punctured. Having three fewer RBs to use for the PBCH may result in reduced performance when decoding the MIB. Note that this corresponds to having a 5-RB offset in Table 11. Diagram 840 in Figure 8 shows a channel with a synchronization raster located at 808. To center the SSB at synchronization raster position 808 while ensuring that the PSS and SSS are within the channel, the SSB is truncated in the frequency domain. In diagram 840, synchronization raster position 808 is three RBs lower in frequency compared to synchronization raster position 804. This truncated SSB has 19 RBs, resulting in a total of three fewer RBs for the PBCH. Note that this corresponds to having a -1 RB offset in Table 11. The truncation conceptually reserves 20 RBs for the SSB. However, one or more RBs are punctured, i.e., one or more RBs are not transmitted by the base station, and the receiver of the UE can assume that no signal / channel is transmitted in the one or more RBs that are not transmitted.

[0124] Thus, in some embodiments, an SSB may be truncated if the synchronization raster position within the channel is at a frequency location such that the SSB cannot be completely contained within the channel bandwidth. For example, as shown in diagrams 820 and 840 of Figure 8, the SSB may be aligned with the synchronization raster position within the channel, and one or more RBs of the SSB that are outside the channel bandwidth may be truncated / punctured.

[0125] Table 10 below shows the minimum number of RBs of an SSB to be punctured for different channel bandwidths when truncation is applied. RB Note that the minimum size of the truncated SSB can be 12 RBs, which can correspond to the length of the SSS and PSS with null subcarriers in the frequency domain. Table 10: Minimum number of RBs to puncture based on Table 9, assuming a 20RB SSB with a 242.5kHz guard band and a 15kHz SCS [Table 10]

[0126] FIG. 9 is an alternative diagram to FIG. 8 that includes a guard band. FIG. 9 illustrates an example of an SSB 902 with a guard band 904 and truncation of the SSB 902 based on the synchronization raster position within a channel having a bandwidth 906. Note that in describing embodiments of the present disclosure, a 5 MHz channel is used for illustrative purposes only. The embodiments of the present disclosure are also applicable to channels with bandwidths smaller than 5 MHz, such as a 3 MHz channel. Diagram 922 in FIG. 9 illustrates a full-sized SSB 902 occupying 20 RBs. This exceeds the channel's bandwidth when the synchronization raster position within the channel is at frequency position 908. The SSB 902 intersects the thick black line on the right (i.e., the right edge of the channel 906). Line 908 (the synchronization raster position) may be in the center of the SSB. Therefore, the channel cannot completely include the SSB 902 within synchronization raster position 908. Synchronization raster position 908 is not a valid synchronization raster position for the SSB 902. In diagram 924, if the synchronization raster position is located at frequency location 910, a truncated SSB 912 having 19 RBs can be used for the channel, with the highest frequency edge of the truncated SSB aligned with the channel edge. In some cases, there may be some gap between the SSB edge and the channel edge. In some embodiments, the alignment of the SSB with the channel edge may be at the lower edge of the channel. As an example, in diagram 926 of FIG. 9, if the synchronization raster position is located at frequency location 914, a truncated SSB 916 having 19 RBs can be used. It is possible to drop (puncture) the first RB of SSB 902. The puncture may be an RE or one or more RBs.

[0127] To support such truncation / puncture, a new table may need to be modified / introduced to map the relationship between the start of the BWP containing CORESET#0 (its bandwidth and offset within RBs) and the start of the SSB. In the frequency domain, the start of the bandwidth part (BWP) containing CORESET#0 is based on the offset from the start of the SSB. The frequency range of the initial DL BWP can be expressed by the number of RBs in CORESET#0. A portion of the current table (Table 13-1 in 38.213) is shown in Table 11 below. For a 24RB CORESET#0 (5MHz BW with 15kHz SCS), the possible positions of the SSB are within the 24RB CORESET#0. As shown in diagram 820 of Figure 8, new entries 5 and 6 for offset values ​​(between the start of the BWP containing CORESET#0 and the start of the SSB) can be introduced. Similarly, new entries for offset values ​​-1 and -2 can be introduced for diagram 840 of Figure 8. One or two RBs of an SSB may be outside the CORESET#0 bandwidth (initial DL BWP), and the UE may use a truncation procedure to take into account those RBs outside the CORESET#0 bandwidth. Clause 13 of 38.213 states: "For operation without shared spectrum channel access, the UE shall assume that, for the SCS of CORESET in the Type0-PDCCH CSS set provided by subCarrierSpacingCommon, the offsets in Tables 13-1 to 13-10 are defined from the lowest RB index in the Type0-PDCCH CSS set to the lowest RB index of the common RB that overlaps with the first RB of the corresponding SS / PBCH block. In Tables 13-7, 13-8 and 13-10, k SSB is defined in [4, TS38.211].

[0128] If the intention of the truncation is to place the SSS / PSS within the channel, the first RB (i.e., the RB with the lowest frequency occupied by the SSB) or the last RB (i.e., the RB with the highest frequency occupied by the SSB) of the SSB block may be outside the channel. Figures 10A and 10B show the location of the SSS / PSS for CORESET #0 for different RB sizes and channel bandwidths. Figure 10A is a diagram 1000 illustrating an example of a 3000 kHz channel 1030 with 13 RBs, and Figure 10B is a diagram 1020 illustrating an example of a 3600 kHz channel 1040 with 17 RBs. Block 1006 represents the PSS and SSS of a 20-RB SSB, and block 1008 represents the PBCH of the SSB that is within the channel (i.e., to be transmitted). Block 1010 represents the truncated / punctured RBs of the (not transmitted) SSB. For a base station transmitting an SSB on channel 1030 having a bandwidth of 13 RBs, the SSB may be truncated, as shown by truncated SSB 1012 or truncated SSB 1014 in Figure 10A. For a base station transmitting an SSB on channel 1040 having a bandwidth of 17 RBs, the SSB may be truncated, as shown by truncated SSB 1022 or truncated SSB 1024 in Figure 10B.

[0129] There are several trade-offs to consider when truncating SSB, one being to minimize the amount of puncturing (reducing PBCH performance degradation) while maintaining the same synchronization raster position, if possible.

[0130] Section 7.4.3.1 of TS38.211 specifies how 240RE within a 20RB SSB are arranged. Numbering starts from 0. Section 7.4.3.1 of TS38.211 specifies the following: First symbol of SSB block: RE{56, 57, ..., 182} is for PSS, RE{0, 1, ..., 55} and {183, 184, ..., 239} are set to 0. · The second and fourth symbols of the SSB block: RE{0, 1, ..., 239} are for the PBCH. Third symbol of SSB block: RE{56, 57, ..., 182} are for SSS, RE{48, 49, ..., 55} and {183, 184, ..., 191} are set to 0, RE{0, 1, ..., 47} and {192, 193, ..., 239} are for PBCH.

[0131] Truncation / puncturing may change the above arrangement. The total number of punctured RBs is multiplied by X. RB Shown as X1 RB Let X be the number of punctured RBs before the start of the PSS / SSS, and X2 RB Let X be the number of punctured RBs after the last position of the PSS / SSS, and X1 RB +X2 RB =X RB Let N denote the number of subcarriers (REs) per RB. sc RB As an example using =12, the general expression for SSB with puncturing is: First symbol of SSB block: RE{56, 57, ..., 182} is for PSS, RE{0, 1, ..., 55} and {183, 184, ..., 239} are set to 0 (this arrangement remains unchanged). Second and fourth symbols of the SSB block: RE{N sc RB X1 RB , N sc RB X1 RB +1, …, N sc RB (20-X2 RB )-1} is for PBCH, and RE{0, 1, ..., N sc RB X1 RB -1} and {N scRB (20-X2 RB ), N sc RB (20-X2 RB )+1, ..., 239} are set to 0. Third symbol of the SSB block: REs{56, 57, ..., 182} are for SSS, REs{48, 49, ..., 55} and {183, 184, ..., 191} are set to 0, and RE{N sc RB X1 RB , N sc RB X1 RB +1, …, 47} and {192, 193, …, N sc RB (20-X2 RB )-1} is for PBCH, and RE{0, 1, ..., N sc RB X1 RB -1} and {N sc RB (20-X2 RB ), N sc RB (20-X2 RB )+1, ..., 239} are set to 0.

[0132] X RB =5, X1 RB =2, and X2 RB An example of X1 = 3 is shown in Figure 11. Figure 11 is a diagram 1100 of an example truncated SSB in which five RBs are punctured from a 20-RB SSB. The truncated SSB includes a 12-RB PSS 1112 in the first symbol, a 12-RB BSSS 1114 in the third symbol, and a PBCH 1116 with some RBs truncated. RB and X2 RB Note that there are several possible values ​​for {X1 RB X2 RB} can have values ​​{1, 4}, {2, 3}, {3, 2} and {4, 1}. RB ≥ 4, one term (i.e., X1 RB or X2 RBIt may be desirable to set either X or B to 4. This also simplifies the general expression for specifying SSB blocks. RB < 4, there may be some possible considerations for truncating SSB. For example, one term (X1 RB or X2 RB ) can be set to 0. One advantage of this setting is that it simplifies the general expression for specifying SSB blocks.

[0133] One observation regarding the puncturing specification is that the UE may need to know the size of the truncated SSB within an RB, especially for initial access. One embodiment is for the UE to assume a minimum size, such as 12 (or 13) RBs, for some candidate channel bandwidths and attempt to decode the PBCH accordingly. Another embodiment is for the standard to specify the size of the truncated SSB per channel bandwidth (and band). Thus, the UE knows the size of the truncated SSB and where the punctured REs are placed. In Table 11 below (right side), an example for CORESET#0 is provided for a 3 MHz channel bandwidth and a truncated SSB of 13 RBs. The offset values ​​are based on the example of Figure 10A. In the example of Figure 10B, the offsets are from 0 to -3.

[0134] Another point regarding Table 13-1 of TS38.213 is the meaning of multiplexing pattern 1 for channels with a bandwidth less than 5 MHz. For legacy UEs, the bandwidth of the BWP containing CORESET#0 is larger than that of the SSB, and the SSB is placed within CORESET#0 in multiplexing pattern 1. For channels with a bandwidth less than 5 MHz, only the PSS / SSS is placed within the BWP containing CORESET#0. The punctured RBs of the SSB are outside the BWP containing CORESET#0. [Table 11] Possible CORESET#0 locations [Table 11]

[0135] There are three types of truncation: truncation starting from the highest SSB RB (RB#19); truncation starting from the lowest SSB RB (RB#0); and truncation of the highest and lowest SSB RBs. Table 12 below shows an example of the analysis results of SSB truncation for the case of 1200 kHz synchronization raster spacing and a 5 MHz channel (assuming M=3). Table 12 also includes an example of "any 1 RB" - the lowest RB is dropped / punctured or the highest RB is dropped / punctured. In some embodiments, this dropping can be based on the cell ID. The cell ID can be obtained after processing the PSS / SSS. As an example, if the cell ID is greater than the value specified in the standard and the result of modulo 3 of the cell ID is 0, the lowest RB is dropped. If the result of the modulo is 1, the highest RB is dropped. Otherwise, no truncation is performed. Note that truncating the SSB reduces the possibility of not finding a valid synchronization raster position in the channel. Another approach is to indicate the set of GSCNs for each band in a table list. A UE (with certain capabilities / features) considers SSBs for which blind detection / hypothesis testing is possible. Once the SSBs are identified, a UE (with certain capabilities / features) can look up the table to determine the relationship between the SSBs and CORESET#0.

[0136] It is easy to detect when the network transmits truncated SSBs. From the UE's perspective, the standard can indicate whether a channel supports truncated SSBs. Table 12: Analysis of 1200 kHz sync raster spacing and 5 MHz channel truncation (assuming M=3) [Table 12]

[0137] If the UE knows whether RBs of an SSB have been truncated, it can modify its behavior to not consider those RBs during decoding. As an example, the UE can use a zero-value log likelihood ratio (LLR) for channel bits of punctured RBs. A zero value can represent a channel bit that is equally likely to be a binary "1" or a binary "0". This may improve the performance of decoding the MIB (by assuming a zero value) instead of attempting decoding using a lower-quality LLR. A new offset may need to be defined to indicate the offset relationship between CORESET#0 and SSB. Another possibility is to use a cell ID to indicate the offset change between CORESET#0 and SSB.

[0138] It is known that puncturing changes the code rate. It is possible to estimate the performance loss (lower bound) due to puncturing. To determine the impact of puncturing, the number of channel bits per RB is shown as an example in Table 13. Note that for an SSB with 20 RBs, the number of channel bits for the PBCH is 1152 bits (48 RBs × 12 REs / RB × 2 bits / RE). The coding rate loss due to the smaller number of channel bits is 10log 10 Calculated using #chan bits / 1152. [Table 13] Code rate loss for various reduced size SSBs [Table 13]

[0139] A 13-RB reduced-size SSB (i.e., an SSB reduced to 13 RBs) can fit into a minimum channel size of 13 RBs (3000 kHz), and a 13-RB reduced-size SSB may be preferable to a 12-RB SSB because it provides a 0.5 dB coding improvement. Similarly, for a 17-RB (3600 kHz) channel size, it may be desirable to use a 17-RB SSB because it provides a 2.1 dB coding improvement over using a 12-RB SSB.

[0140] Note that there are other approaches to mitigate the performance loss due to puncturing. Some examples are given below. a) Accumulating multiple reduced-size SSBs (implementation approach). The UE receives several reduced-size (punctured / truncated) SSBs. If the first attempt to decode the PBCH is unsuccessful, the UE can store the log-likelihood ratio (LLR) associated with the PBCH. When the UE receives the next SSB, it attempts to combine the LLRs of the previous and current SSBs and decode them. The UE can repeat this process for other SSBs. b) Power boosting (implementation method): The base station modifies the power per RE so that certain REs have more power than others, subject to the constraint that the total symbol power remains the same. More details are provided below. c) Increasing the number of SSBs transmitted in a frame. This is a standard approach that can be combined with SSB accumulation and power boosting.

[0141] Power boosting allows the base station to change the power distribution of each RE within a symbol. RB chan Assuming there are RBs, N RE RB = 12 REs, total power is P max The power (linear) per RE is:

number

[0142] If the power of one RE set is reduced, the power reduction may be distributed to another RE set. Next, we show an example that explores the power reduction when puncturing RBs from the PBCH. This can be easily extended to PSS / SSS power reduction.

[0143] In this example, the number of RBs for PBCH is N RB PBCH , N RB PBCH ≦N RB chan and the number of REs in PSS / SSS is N RE PSS = 127, the number of RBs occupied by PSS / SSS and null RE is N RE PSS Assume that =12.

[0144] Without power boosting, the power per symbol for a punctured SSB is shown in Table 14. N RB chan Assume it is <20. [Table 14] Power of each symbol [Table 14]

[0145] For the second and fourth symbols, N RB PBCH <N RB chan In the case of N RB PBCH N RE RB REs total 10log 10 N RB chan / N RB PBCH The third symbol is (N RB PBCH -N RB PSS )N RE RBFor REs, 10log 10 N RB PSS N RE RB / N RE PSS +10log 10 N RB chan / N RB PBCH dB power boost. The first term is 10log 10 N RB PSS N RE RB / N RE PSS is N RB PBCH <N RB chan The second term is due to 10log 10 N RB chan / N RB PBCH is (N RB PSS N RE RB -N RE PSS ) 0-power REs. Note that the power of the PSS / SSS may be reduced and additional power may be applied to the third symbol.

[0146] 3. Mapping to synchronous rasters In some cases, even with truncated / punctured SSBs, the current synchronization raster may not be sufficient to position the SSBs in the channel.

[0147] The equations for identifying raster positions can be generalized to include puncturing of the PBCH. As shown in Figure 12, the example equations use the following notation: P RB =12 represents the number of RBs for PSS / SSS, and Y1 RB is 0≦Y1 RB ≦4, represents the number of RBs used for PBCH located at a frequency lower than PSS / SSS, Y2 RB is 0≦Y2RB ≦4, and represents the number of RBs used for the PBCH located at frequencies higher than the PSS / SSS, and G represents the guard band. In this notation, for i=1,2, Xi RB +Yi RB = 4, and Xi RB is shown in Figure 11 representing a truncated RB.

[0148] For convenience, the following formula is used.

number

[0149] The above formula allows combining puncturing and raster design. The use of half RE (the constant term "0.5" in the formulas for h1 and h2) is for mathematical convenience. Some refinement may be required for the actual position.

[0150] It is clear that equation (7) can be expressed as follows:

number

number

[0151] For frequencies below 3 GHz, similar modifications can be made. For M=3, the condition for no valid sync raster position within the channel in equation (15) becomes:

number

[0152] For M=1, 3, 5, the condition for no valid sync raster position in the channel of equation (23) is:

number

[0153] For channels below 5 MHz, using Table 9 and equation (24), the current synchronization raster position may not be used to identify the center of the SSB. However, the current synchronization raster position may be valid for a truncated SSB. Thus, in some embodiments, a condition for not having a valid synchronization raster position within the channel for a truncated SSB may be determined and checked to determine if there is a valid synchronization raster position within the channel for the truncated SSB. Table 15 below shows examples of several bandwidths and truncated SSBs. Table 15 shows various channel bandwidths, associated conditions for not having a valid synchronization raster position, and the truncation pattern for the PBCH (Y1 RB and Y2 RB The conditions in Table 15 include two columns that are generated by modulo arithmetic. The two columns can be used as a logical "or." In the description, the terms "puncture pattern," "puncturing pattern," and "truncation pattern" are used interchangeably. Table 15: Conditions for no valid sync raster position when puncturing SSB as a function of channel bandwidth [Table 15]

[0154] Table 15 can be used to determine whether there is a valid synchronization raster position for a particular puncture pattern. For example, if the channel bandwidth of band n100 is 3600 kHz and the downlink frequency span is (919.4 MHz to 923 MHz), then 919400 mod ΔF raster =200. Looking at Table 15, 12RB SSB{Y1 RB =0,Y2 RB =0}, 13RB SSB{Y1 RB =1,Y2 RB =0}, 14RB SSB{Y1 RB =2,Y2RB =0}, 15RB SSB{Y1 RB =3,Y2 RB =0}, and 16RB SSB{Y1 RB =4,Y2 RB =0}, there is a valid sync raster position. For ease of explanation, in the following, SSB{N1, N2} is defined as SSB{Y1 RB =N1,Y2 RB =N2}, which indicates the number of punctured RBs before PSS / SSS and after PSS / SSS. As another example, for the band (936.5 to 939.5 MHz), 936500 mod △F raster = 500. Even if the SSB is punctured to 12 or 13 RBs, there is no valid sync raster position at 3000 kHz. As another example, for the band (788-791 MHz), 788000 mod △F raster = 800. A valid 3000 kHz sync raster position can be either 12RB{0,0} or 13RB{1,0}. This formula allows the selection of a puncturing (or puncture, truncation) pattern that does not affect the sync raster design.

[0155] For bands without a valid sync raster position, another embodiment checks for changes in raster parameters.

[0156] When the frequency is less than 3 GHz, ΔF in the formula shift Change Currently, ΔF shift The value of is 50 kHz. This means that for m=1, 3, 5, the synchronous raster position is 1200 + {50, 150, 250} kHz. For a particular band, ΔF shift can be redefined to a different value. shift Here is an example that explores the benefits of redefining ΔF shift = 200kHz and ΔF shift = 400 kHz. shift Substituting = 200 kHz into equation (3) and performing the same analysis on Table 15, we get the following results, as shown in Table 16: [Table 16]ΔFshift Conditions for no valid sync raster positions when puncturing SSB as a function of the channel bandwidth = 200 kHz [Table 16]

[0157] Table 16 shows 919400modΔF raster For the band n100 = 200, if a truncated SSB size of 13 to 16 RBs, excluding 16 RBs {4, 0}, is used, there is a valid synchronization raster position for the 3600 kHz channel (936.5 to 939.5 MHz) band, 936500 mod ΔF. raster At = 500, there is a valid synchronization raster position for a 3000 kHz channel when a truncated SSB size of 12 or 13 RBs is considered. (788-791 MHz) band, 788000 mod ΔF raster At =800, there is a valid sync raster position for the 3000 kHz channel if either a 12 RB SSB{0,0} or a 13 RB SSB{0,1} is used.

[0158] In one embodiment, ΔF shift The key is to select.

[0159] ΔF shift = 400 kHz can be considered. However, the derivation of (30) is shift However, this is not applicable when the value of ΔF is large. raster It is possible to use (28) at = 400 kHz. [Table 17]ΔF raster Conditions for no valid sync raster position when puncturing SSB as a function of the channel bandwidth = 400 kHz [Table 17]

[0160] Using Table 17, band n100, 919400 mod ΔFraster For =200, there are valid synchronization raster positions for 3600 kHz channels and several RB / puncture patterns. As an example, for the (936.5-939.5 MHz) band, 936500 mod ΔF raster At =100, there are valid sync raster positions for 3000 kHz channels and 12RB SSB (788-791 MHz) band, 788000 mod ΔF raster = 0, there is a valid sync raster position for a 3000 kHz channel and for either a 12 RB SSB{0,0} or a 13 RB SSB{1,0}. shift There may be a specific value for

[0161] 13 is a flowchart of an embodiment operation 1300 for detecting an SSB in a channel. Method 1300 may represent operations performed by a UE. The UE may detect an SSB in a band with a punctured SSB and a different ΔF shift If the UE is capable of operating with truncated / punctured SSBs, the UE may check the bands it is monitoring when scanning frequencies for possible SSB locations. If the band is not ΔF, the UE may determine whether to use ΔF. shift If the UE has different values ​​of ΔF and can use punctured SSBs, shiftThe UE may search for the SSS / PSS at the synchronization raster position indicated by (block 1304). If the PSS / SSS is found at the synchronization raster position (e.g., high correlation) (block 1306), the UE may start detecting the PBCH (block 1308). If the location of the punctured RBs is known (e.g., channel / band-specific puncture pattern), the UE may assume that the log-likelihood ratio (LLR) of the punctured RE is 0 and start decoding the PBCH. The UE may accumulate LLRs from several SSBs (continuous trials) to improve the quality of the LLR before decoding. After decoding the MIB, the UE may determine the parameters (e.g., location) of CORESET#0 and the associated BWP using a table similar to Table 11 (right side) (block 1310). If the PSS / SSS is not found (block 1306), the UE may proceed to block 1304 and search for another synchronization raster position for the PSS / SSS.

[0162] Bandwidth is ΔF shift If the UE does not have different values ​​of ΔF and cannot use punctured SSBs, the UE shift The UE may search for the PSS / SSS at a synchronization raster position indicated by a normal value of (block 1312). If the PSS / SSS is found at the synchronization raster position (block 1314), the UE may attempt to detect the PBCH (block 1316) and determine CORESET#0 (block 1318) and associated BWP parameters based on the MIB obtained from the PBCH. If the PSS / SSS is not found (block 1314), the UE may proceed to block 1312 and search for the PSS / SSS at another synchronization raster position, if available on the channel.

[0163] Alternative Channels If the condition for no valid synchronization raster position is met for a channel, in one embodiment, the network can transmit the SSB on another channel, e.g., on a channel with a valid synchronization raster position. In this case, no change in UE operation is required. As used herein, the term "alternative" can mean used instead of or in addition to.

[0164] From a network perspective, this embodiment may complicate cell frequency deployment, as the selection of different channels may not always work taking into account the operator's spectrum allocation.

[0165] Some approaches to alternate channel selection are illustrated in Figure 14. Figure 14 is a diagram 1400 showing an example channel without a valid synchronization raster position and example possible channels that can be used. Figure 14A shows the first 5 MHz channel 1402 in a 20 MHz band (dotted block), which does not have a valid synchronization raster position. Figure 14B shows the "next channel" of channel 1402 in the 20 MHz band. In this example, the 20 MHz band may be divided into four 5 MHz channels, and the next channel 1404 after channel 1402 may be an alternate channel (with a valid synchronization raster position) for channel 1402. The network may select next channel 1404 to transmit the SSB. This is called the next channel approach. Figure 14C shows a "shifted channel." In this example, the channelization is slightly shifted (frequency offset 1406), and the 5 MHz channel (1408) closest to the band edge and with a valid synchronization raster position is selected to transmit the SSB. This is called the shifted channel approach. Figure 14(D) shows a "larger channel" 1410, which may be a 10 MHz channel as an example. In this example, instead of using a 5 MHz channel, the network can select a 10 MHz channel to transmit the SSB. This approach is called the larger channel approach. In Figure 14, channels 1404, 1408, and 1410 show various candidate channels (alternate channels) that can be used to transmit the SSB if channel 1402 does not have a valid synchronization raster position for the SSB.

[0166] Some observations regarding the alternative channels shown in Figures 14(B)-(D) are presented below.

[0167] In Figure 14B, the next channel approach is simple, but has the disadvantage that if one channel does not have a valid sync raster position, another channel (not necessarily the next channel in frequency) may not have a valid sync raster position. Some examples are given below:

[0168] Example 1, △F raster Assume a 15 kHz SCS with f = 1200, 5 MHz channels, and M = 3. L mod, △F raster If = 600, the next channel (i.e., (f L +5000)mod△F raster =800) indicates that the next channel has a valid sync raster position. However, the channel 30 MHz away does not have a valid sync raster position: (f L +30000)mod△F raster = 600. This pattern can be seen in Table 5.

[0169] Example 2: △F in Table 7 raster = 1440 kHz, f L mod△F raster = 840. The following 5 MHz channels have valid sync raster positions: (f L +5000)mod△F raster =80 Further examination of Table 7 reveals that there are spans where all other channels do not have valid sync raster positions. This is similar to Table 8.

[0170] The following relationships:

number

[0171] The following channel approach can complicate network planning. It is desirable to place 5 MHz channels in dedicated portions of the band (the band's edges), and if a valid synchronization raster position cannot be found on that channel, another channel must be used (e.g., the center of the band). In another example of coexistence, in Rel. 17, RedCap UEs supporting up to 20 MHz channels can be deployed. Network operators may want to restrict Rel-18 RedCap UEs to a specific 5 MHz channel. If that channel does not have a valid synchronization raster position, the operator must consider alternative channelization. In another example, a 5 MHz bandwidth Rel-18 RedCap UE can be deployed with a 20 MHz RedCap UE. A consideration regarding presence is that the desired 5 MHz channel may not have a valid synchronization raster position. An alternative channel can be found in the 20 MHz channel, but that channel may not be preferred by the network.

[0172] In the shifted channel approach of Figure 14(C), the alternate 5 MHz channel begins at some offset from the original 5 MHz channel (which has no valid synchronization raster position). As an example, for a 15 kHz SCS and 1200 kHz raster spacing, equation (31) can be used to show that an offset of 300 + 1200 kHz (<2 RBs for k = 0) is sufficient for k > 0 to find a valid synchronization raster position. However, this approach has at least two drawbacks. The first drawback is the presence of unused spectrum (e.g., 300 kHz + 4700 kHz at the other end of the band). The second drawback is that another channel that originally had a valid synchronization raster position within the band may no longer have a valid synchronization raster position due to the offset. The shifted channel approach can complicate network planning, such as network planning for interference measurements.

[0173] The larger channel approach in Figure 14(D) overcomes the drawbacks of the shifted channel and next channel approaches by networks that use larger channel bandwidths, such as 10 MHz, instead of 5 MHz channels. A larger channel is essentially any channel whose bandwidth exceeds the SSB bandwidth by at least the raster interval. This means that with a larger channel, there is always one valid synchronization raster position. In NR, the next larger channel bandwidth is at least 5 MHz. Using larger channels than desired can complicate network planning.

[0174] Embodiment: Alternate sync raster positions within a channel. If the alternate channel approach is not desired for a network deployment, approaches to introduce valid synchronization raster positions within the channel can be considered. In some embodiments, two possible alternate synchronization raster positions can be used, based on the use of smaller (or reduced) raster spacing or displacement (of the synchronization raster position or shift / offset). The alternate synchronization raster position approach can be combined with an SSB puncturing approach to provide valid synchronization raster positions within the channel for SSB transmission. Combinations will be apparent to those skilled in the art with reference to this disclosure. Those skilled in the art will recognize that various embodiments, modifications, and alternatives are possible without departing from the spirit and scope of this disclosure.

[0175] When considering equation (8), reducing the raster spacing so that the reduced raster spacing is less than or equal to the difference between the channel bandwidth and the SSB bandwidth will ensure that a valid synchronization raster position exists (at the reduced raster spacing). An example of a reduced raster spacing is ΔF' for k=2, 3, ... for a particular channel in the band. raster =△F rasterThe best way to achieve this is to use / k. k may have to satisfy other constraints; for example, for frequencies below 3 GHz in NR, k must divide 240 perfectly (240 = 1200000 / 5000 Hz raster spacing [minimum granularity is 5 kHz]). For frequencies between 3 and 24 GHz, k may be constrained to divide 96 perfectly. In the example band n1, the bandwidth difference between the channel and SSB is 900 kHz. If k=2 and 600 kHz is used as the raster spacing instead of 1200 kHz, valid synchronous raster positions may exist within channels with reduced raster spacing.

[0176] With a shifted synchronization raster, if the channel cannot support valid synchronization raster positions within the channel, a displacement (or shift, offset) from the set of synchronization raster positions allows the SSB to fit within the channel. In some embodiments, one possible displacement may be a multiple of RBs. For example, for a 15 kHz SCS, one RB represents 180 kHz in frequency. For a 1200 kHz raster spacing, a displacement of two RBs may be used (because a 900 kHz difference + a 360 kHz offset (2 RBs) > 1200 kHz). For a 1400 kHz raster spacing, a displacement of three RBs may be used (because a 900 kHz difference + a 540 kHz offset >= 1440 kHz). In general, if the synchronization raster position is f, the UE can look up f + Δ. Δ is the frequency displacement value, which can be either positive or negative and can be a positive / negative multiple of the RB size. The value of Δ can also be obtained using Equation (31), which is based on some modulo arithmetic. In some embodiments, the same displacement value (Δ) can be used for FR1, such as 3RB. Note that 3RB is also a possible displacement for frequencies below 3 GHz.

[0177] Figure 15 is a diagram 1500 showing examples of alternate raster positions for SSBs within a channel. In Figure 15, (A) shows an example where a 5 MHz channel 1502 does not have a valid synchronous raster position for SSB 1504. This is an example of Table 5, f L=2,110,000kHz and DF raster = 1200 kHz, f L modDF raster = 400. The center of the SSB is aligned with sync raster position 1506. Black vertical lines, e.g., 1508, represent potential sync raster positions within channel 1502. These sync raster positions 1508 may be predefined. Dotted lines 1510 indicate the edges of channel 1502. In this example, if SSB 1504 were located at any sync raster position within channel 1502, e.g., sync raster position 1506, it would intersect the edge of channel 1502. Therefore, no valid sync raster positions exist for SSB 1504 in this channel 1502.

[0178] 15B shows an example using an embodiment with a smaller raster spacing, where k=2. Lines 1522 and 1524 indicate additional raster positions introduced into channel 1502 by using a smaller raster spacing. The center of SSB 1504 can be aligned with synchronous raster position 1524 so that SSB 1504 is contained within the channel bandwidth. Thus, by using a smaller raster spacing, there can be a valid raster position (e.g., 1524) for SSB 1504 within channel 1502.

[0179] 15C shows an example using the displacement approach of an embodiment with a shift / offset of 2 RBs. Lines 1532 and 1534 show additional raster positions introduced into channel 1502 by displacing synchronous raster position 1508 by 2 RBs. The center of SSB 1504 may be aligned with synchronous raster position 1534 so that SSB 1504 is included in channel 1502.

[0180] From a detectability perspective, the use of an alternative raster position can be detected if UEs that support this type of synchronous raster position can perform initial access successfully, and legacy UEs cannot perform initial access.

[0181] A network may use the checks in Table 4 to determine whether a channel can support a valid synchronization raster position with a raster interval defined in the Rel. 17 version of the 38.104 / 38.101-1 / 38.101-2 standard (or as described in Table 1). Alternate synchronization raster positions may be used (depending on the implementation) by the network when performing the checks.

[0182] Assume that the UE knows whether the channel (band) can use alternate synchronization raster positions. From one perspective, there may be two sets of synchronization raster positions for the UE. The first set may be called "legacy" and is based on the synchronization raster positions in the Rel. 17 version. These positions may be defined by Table 2 for a particular band. For example, the first set of synchronization raster positions for band n1 ranges from 5279 to 5419 in Table 1. The second set includes alternate synchronization raster positions. The second set can be calculated from the first set. For example, in the 3 to 24 GHz range, the alternate synchronization raster positions are 0.72 MHz (corresponding to raster spacing / 2) greater than the frequencies corresponding to raster points from the first set when the reduced raster spacing method is used. In the displacement method, the alternate synchronization raster positions are 3 RBs (3 × 180 kHz = 540 kHz) greater than the frequencies corresponding to raster points from the first set. As another example, in the frequency range from 0 to 3 GHz, for convenience of explanation, M=3. At a reduced raster spacing of 0.60 MHz (corresponding to raster spacing / 2), the alternate synchronization raster position is greater than the frequency corresponding to the raster point from the first set. Due to the displacement technique, the alternate synchronization raster position is 2RB (2 x 180 kHz = 360 kHz) greater than the frequency corresponding to the raster point from the first set.

[0183] 16 and 17 illustrate two exemplary UE operations for detecting SSBs when alternate synchronization raster positions for SSBs are supported in 5 MHz channels of a band. Note that the order in which the UE searches for synchronization raster positions may be implementation-specific. However, the order of frequencies examined may be determined by a sensor monitoring the receive frequencies used by the UE. FIG. 16 is a flowchart of embodiment operations 1600 for detecting SSBs in a band. Operations 1600 begin at block 1602, where the UE may combine synchronization raster positions from both the first set and the second set (if the band supports alternate synchronization raster positions) (block 1604). The UE may search for SSBs based on the combined set of synchronization raster positions. The UE may obtain frequency locations of synchronization raster positions in the combined set to identify the SSB (block 1606). For example, the UE may select a GSCN using Table 1 and calculate the frequency corresponding to the GSCN using Table 2. The UE may detect SSBs at the obtained frequency locations of the synchronization raster positions (block 1608). For example, the UE may assume that the center frequency of the SSB is at the frequency location of the synchronization raster position. If the SSB is detected, the UE monitors the SIB based on resource information obtained from the SSB (block 1610). If the SSB is not detected, the UE may proceed to block 1606 and check another synchronization raster position to identify the SSB. For example, the UE may select another GSCN using Table 1, obtain the corresponding frequency of this GSCN, and detect the SSB based on this frequency. If the UE checks all possible synchronization raster positions in the band and does not detect the SSB, the method stops.

[0184] FIG. 17 is a flowchart of another embodiment method 1700 for detecting an SSB in a band. The UE attempts to detect an SSB using a frequency from a first set. If unsuccessful, the UE may search for an SSB using a frequency from a second set if the band supports alternate synchronization raster positions. Method 1700 begins at block 1702, where the UE determines whether there is at least one additional synchronization raster position to check in the first set (block 1704). If the answer is yes, the UE obtains the frequency location of the synchronization raster position to check to identify the SSB (block 1706). The UE may then detect the SSB based on the frequency location (block 1708). If the SSB is detected, the UE monitors the SSB based on resource information obtained from the SSB (block 1710). If the SSB is not detected, the UE may proceed to block 1704 and check the next available synchronization raster position in the first set. If there are no more synchronization raster positions to check in the first set, the UE may check a second set of synchronization raster positions if alternative synchronization raster positions are supported by the band. The UE obtains frequency locations of synchronization raster positions in the second set for identifying an SSB (block 1712) and detects the SSB based on the frequency locations (block 1714). If an SSB is detected, the UE proceeds to block 1710 and monitors for an SSB. If an SSB is not detected, the UE may proceed to block 1712 and check the next synchronization raster position in the second set to detect an SSB. If the UE does not detect an SSB after checking all synchronization raster positions in the second set, method 1700 stops.

[0185] To apply the alternate sync raster position approach, the standard may need to specify which bands can support alternate sync raster positions. One possible implementation is to add a column to the existing sync raster table indicating whether a band supports alternate sync raster positions. If multiple types (e.g., displacement, reduced raster spacing) are used, the type can be captured in the table. Table 18 shows such an example. As shown, the column "supports alternate sync raster positions" is added to indicate whether the corresponding band supports alternate sync raster positions. [Table 18] Relationship between frequency bands and GSCN (part of Table 5.4.3.3-1 of TS38.104) [Table 18]

[0186] Section 13 of TS38.213 provides a table showing the RB offset between the first RE of an SSB and the first RE of CORESET#0. One advantage of the displacement technique is that the shift is known (e.g., 2 RBs for frequencies below 3 GHz, 3 RBs for frequencies between 3 GHz and 24 GHz). This shift can be incorporated into the formula for the RB offset between the first RE of an SSB and the first RE of CORESET#0. Figure 18 is a diagram showing example positions of SSB 1802 (hatched box) and CORESET#0 1804 (dotted box) in the time-frequency grid, highlighting the displaced raster positions. Diagram 1800 shows the current offset of 2 RBs between the first RE of SSB 1802 and the first RE of CORESET#0 1804. With the displacement technique used (e.g., using a 2 RB shift), the offset would be 4 RBs between the first RE of SSB 1802 and the first RE of CORESET#0 1804, as shown in diagram 1820. However, since the UE knows that this SSB is shifted by 2 RBs, the UE can add 2 to the offset to determine the location of CORESET#01804.

[0187] FIG. 19 is a flowchart 1900 of an embodiment of the operation of a UE to locate an SSB within a band. The UE may prepare to search for a synchronization raster position within the band (block 1902). For example, the UE may obtain GSCN information for the band using Table 1. Based on the band in which the UE is currently operating, the UE may obtain / select a frequency corresponding to the first / next allowable GSCN for the band. The selected frequency is the synchronization raster position, and the UE may obtain the frequency of the synchronization raster position to search for (locate) an SSB within the band (block 1904). Note that the GSCN is a set of integers from 1 to 26639 (Table 2). For a band, there is a range of GSCNs, and the set of allowable GSCNs is a subset of that range. The offset in Table 1 is one parameter used to define the subset.

[0188] The UE may attempt to detect an SSB having a center frequency corresponding to an allowable GSCN (i.e., a synchronization raster position) (block 1906). An SSB may have one or two possible SCS candidates. If the UE cannot detect the SSB, the UE may proceed to block 1904 and select another GSCN within the band (i.e., obtain another synchronization raster position). If there are no more allowable GSCNs within the band, the UE may select another band. If the UE detects the SSB, the UE may establish an initial DL BWP and then receive SIBs based on the detected SSB (block 1908).

[0189] FIG. 20 is a flowchart of an embodiment method 2000 for SSB communication. Method 2000 illustrates operation of a user equipment (UE). As shown, the UE may receive a punctured synchronization signal block (SSB) of a first SSB in a channel of a frequency band from a base station (block 2002). The first SSB may include a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS). The punctured SSB may include a punctured PBCH, PSS, and SSS. The punctured PBCH may be derived from a first PBCH by applying a first puncture pattern to the first PBCH to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission. The center frequency of the PSS of the punctured SSB is indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band, and the first puncture pattern is associated with the first synchronization raster position. The UE may detect the punctured SSB according to the first synchronization raster position (block 2004). The punctured PBCH may carry information used to determine the frequency location of the channel. As an example, the punctured PBCH may include an index from Table 11. The UE may determine the frequency location of the channel based on information, such as an offset, included in the entry corresponding to the index. The offset may be associated with the difference between the starting frequency location of the channel and the center frequency of the PSS (or a particular RB in the PSS).

[0190] FIG. 21 is a flowchart of an embodiment method 2100 for SSB communication. Method 2100 illustrates operation at a base station. As shown, the base station can generate a punctured synchronization signal block (SSB) for a channel of a frequency band based on a first SSB, and the punctured SSB is transmitted within the channel (block 2102). The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS), and the bandwidth of the first SSB exceeds the bandwidth of the channel. The punctured SSB includes a punctured PBCH, PSS, and SSS of the first PBCH. The punctured PBCH can be derived from the first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission. The center frequency of the PSS of the punctured SSB is indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band, and the first puncture pattern is associated with the first synchronization raster position. The base station may transmit the punctured SSB within the channel, for example, to a UE (block 2104). The first SSB may be punctured as described in the above embodiments.

[0191] Embodiments of the present disclosure enable communication of synchronization signal blocks in a channel having a small bandwidth, for example, a bandwidth of 5 MHz or less, and enable support for wireless communication of devices operating in small bandwidths.

[0192] 22 illustrates an exemplary communications system 2200. Generally, the system 2200 enables multiple wireless or wireline users to transmit and receive data and other content. The system 2200 can implement one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), or non-orthogonal multiple access (NOMA).

[0193] In this example, communication system 2200 includes electronic devices (EDs) 2210a-2210c, radio access networks (RANs) 2220a-2220b, a core network 2230, a public switched telephone network (PSTN) 2240, the Internet 2250, and other networks 2260. Although a particular number of these components or elements are shown in FIG. 22, any number of these components or elements may be included in system 2200.

[0194] The EDs 2210a-2210c are configured to operate or communicate in the system 2200. For example, the EDs 2210a-2210c are configured to transmit or receive signals over wireless or wired communication channels. Each ED 2210a-2210c represents any suitable end-user device and may include (or be referred to as) a user equipment or device (UE), a wireless transmit or receive unit (WTRU), a mobile station, a fixed or mobile subscriber unit, a mobile phone, a personal digital assistant (PDA), a smartphone, a laptop, a computer, a touchpad, a wireless sensor, or a consumer electronic device.

[0195] Here, the RANs 2220a-2220b include base stations 2270a-2270b, respectively. Each base station 2270a-2270b is configured to wirelessly interface with one or more of the EDs 2210a-2210c to enable access to the core network 2230, the PSTN 2240, the Internet 2250, or other networks 2260. For example, the base stations 2270a-2270b can include (or be) one or more of several well-known devices, such as a base transceiver station (BTS), a Node-B (NodeB), an evolved NodeB (eNodeB), a Next Generation (NG) NodeB (gNB), a Home NodeB, a Home eNodeB, a site controller, an access point (AP), or a wireless router. The EDs 2270a-2210c are configured to interface and communicate with the Internet 2250 and can access the core network 2230, the PSTN 2240, or other networks 2260.

[0196] In the embodiment shown in Figure 22, base station 2270a forms part of RAN 2220a, which may include other base stations, elements, or devices. And base station 2270b forms part of RAN 2220b, which may include other base stations, elements, or devices. Each base station 2270a-2270b operates to transmit or receive radio signals within a particular geographic region or area, sometimes referred to as a "cell." Some embodiments may employ multiple-input multiple-output (MIMO) technology with multiple transceivers for each cell.

[0197] The base stations 2270a-2270b communicate using wireless communication links with one or more EDs 2210a-2210c via one or more air interfaces 2290. The air interfaces 2290 may utilize any suitable radio access technology.

[0198] It is contemplated that system 2200 can employ multiple channel access capabilities, including schemes such as those described above. In particular embodiments, the base stations and EDs implement 5G New Radio (NR), LTE, LTE-A, or LTE-B. Of course, other access schemes and radio protocols can be utilized.

[0199] The RANs 2220a-2220b communicate with a core network 2230 to provide voice, data, application, Voice over Internet Protocol (VoIP), or other services to the EDs 2210a-2210c. Of course, the RANs 2220a-2220b or the core network 2230 may communicate directly or indirectly with one or more other RANs (not shown). The core network 2230 may also serve as gateway access to other networks (e.g., the PSTN 2240, the Internet 2250, and other networks 2260). Additionally, some or all of the EDs 2210a-2210c may include the capability to communicate with different wireless networks over different wireless links using different wireless technologies or protocols. Instead of (or in addition to) wireless communication, the EDs may communicate with a service provider or switch (not shown) and the Internet 2250 via wired communication channels.

[0200] Although Figure 22 illustrates an example communication system, various modifications can be made to Figure 22. For example, communication system 2200 can include any number of EDs, base stations, networks, or other components in any suitable configuration.

[0201] 23A and 23B illustrate example devices that can implement methods and teachings according to the present disclosure. In particular, FIG. 23A illustrates an example ED 2310, and FIG. 23B illustrates an example base station 2370. These components may be used in system 2200 or any other suitable system.

[0202] As shown in FIG. 23A , the ED 2310 includes at least one processing unit 2300. The processing unit 2300 performs various processing operations of the ED 2310. For example, the processing unit 2300 may perform signal coding, data processing, power control, input / output processing, or any other function within the system 1000. The processing unit 2300 also supports the methods and teachings described in more detail above. Each processing unit 2300 includes any suitable processing or computing device configured to perform one or more operations. Each processing unit 2300 may include, for example, a microprocessor, a microcontroller, a digital signal processor, a field programmable gate array, or an application-specific integrated circuit.

[0203] The ED 2310 also includes at least one transceiver 2302. The transceiver 2302 is configured to modulate data or other content to be transmitted by at least one antenna or NIC (Network Interface Controller) 2304. The transceiver 2302 is also configured to demodulate data or other content received by the at least one antenna 2304. Each transceiver 2302 includes any suitable structure for generating signals for wireless or wired transmission or processing signals received wirelessly or wired. Each antenna 2304 includes any suitable structure for transmitting and receiving wireless or wired signals 2390. One or more transceivers 2302 may be used in the ED 2310, and one or more antennas 2304 may be used in the ED 2310. Although shown as a single functional unit, the transceiver 2302 may also be implemented using at least one transmitter and at least one separate receiver.

[0204] The ED 2310 further includes one or more input / output devices 2306 or interfaces (e.g., a wired interface to the Internet 2250). The input / output devices 2306 enable interaction with a user or other devices in a network (network communications). Each input / output device 2306 includes any structure suitable for providing information to or receiving information from a user, such as a speaker, microphone, keypad, keyboard, display, touchscreen, etc., including network interface communications.

[0205] Additionally, the ED 2310 includes at least one memory 2308. The memory 2308 stores instructions and data used, generated, or collected by the ED 2310. For example, the memory 2308 may store software or firmware instructions executed by the processing unit 2300 and data used to reduce or eliminate interference in incoming signals. Each memory 2308 includes any suitable volatile or non-volatile storage and retrieval device. Any suitable type of memory may be used, such as random access memory (RAM), read only memory (ROM), hard disk, optical disk, subscriber identity module (SIM) card, memory stick, secure digital (SD) memory card, etc.

[0206] As shown in FIG. 23B , the base station 2370 includes at least one processing unit 2350, at least one transceiver 2352 including transmitter and receiver functionality, one or more antennas 2356, at least one memory 2358, and one or more input / output devices or interfaces 2366. A scheduler is coupled to the processing unit 2350, as would be understood by one skilled in the art. The scheduler may be included within the base station 2370 or may operate separately from the base station 2370. The processing unit 2350 implements various processing operations of the base station 2370, such as signal coding, data processing, power control, input / output processing, or any other function. The processing unit 2350 may also support the methods and teachings described in more detail above. Each processing unit 2350 includes any suitable processing or computing device configured to perform one or more operations. Each processing unit 2350 may include, for example, a microprocessor, a microcontroller, a digital signal processor, a field programmable gate array, or an application-specific integrated circuit.

[0207] Each transceiver 2352 includes any suitable structure for generating signals for wireless or wired transmission to one or more EDs or other devices. Each transceiver 2352 further includes any suitable structure for processing signals received wirelessly or wired from one or more EDs or other devices. While shown combined as a transceiver 2352, the transmitter and receiver may be separate components. Each antenna 2356 includes any suitable structure for transmitting and receiving wireless or wired signals 2390. While a common antenna 2356 is shown here coupled to the transceiver 2352, one or more antennas 2356 may be coupled to the transceiver 2352, and separate antennas 2356 may be coupled to the transmitter and receiver if implemented as separate components. Each memory 2358 includes any suitable volatile or non-volatile storage and retrieval device. Each input / output device 2366 enables interaction with users or other devices in the network (network communications). Each input / output device 2366 includes any suitable structure for providing information to a user or receiving / providing information from a user.

[0208] FIG. 24 is a block diagram of a computing system 2400 that can be used to implement the apparatus and methods disclosed herein. For example, the computing system can be any entity in a UE, access network (AN), mobility management (MM), session management (SM), user plane gateway (UPGW), or access stratum (AS). A particular device can use all of the components shown or only a subset of the components, and the level of integration can vary from device to device. Furthermore, a device can include multiple instances of components such as multiple processing units, processors, memories, transmitters, and receivers. Computing system 2400 includes a processing unit 2402. The processing unit includes a central processing unit (CPU) 2414, memory 2408, and can further include a mass storage device 2404, a video adapter 2410, and an I / O interface 2412 connected to a bus 2420.

[0209] The bus 2420 can be one or more of several types of bus architectures, including a memory bus or memory controller, a peripheral bus, or a video bus. The CPU 2414 can include any type of electronic data processor. The memory 2408 may include any type of non-transitory system memory, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), read-only memory (ROM), or a combination thereof. In one embodiment, the memory 2408 may include ROM for use at boot-up and DRAM for program and data storage for use during program execution.

[0210] Mass storage 2404 may include any type of non-transitory storage device configured to store data, programs, and other information and make the data, programs, and other information accessible via bus 2420. Mass storage 2404 may include, for example, one or more of a solid state drive, a hard disk drive, a magnetic disk drive, or an optical disk drive.

[0211] Video adapter 2410 and I / O interface 2412 provide interfaces for coupling external input and output devices to processing unit 2402. As shown, examples of input and output devices include a display 2418 coupled to video adapter 2410, and any combination of a mouse, keyboard, or printer 2416 coupled to I / O interface 2412. Other devices may be coupled to processing unit 2402, and additional or fewer interface cards may be utilized. For example, a serial interface such as a Universal Serial Bus (USB) (not shown) may be used to provide an interface for external devices.

[0212] The processing unit 2402 also includes one or more network interfaces 2406, which may include wired links, such as Ethernet cables, or wireless links for accessing nodes or different networks. The network interface 2406 allows the processing unit 2402 to communicate with remote units over a network. For example, the network interface 2406 may provide wireless communication via one or more transmitters / transmit antennas and one or more receivers / receive antennas. In one embodiment, the processing unit 2402 is coupled to a local area network 2422 or a wide area network for data processing and communication with remote units, such as other processing units, the Internet, or remote storage devices.

[0213] It should be understood that one or more steps of the methods of the embodiments provided herein may be performed by a corresponding unit or module. For example, a signal may be transmitted by a transmitting unit or a transmitting module. A signal may be received by a receiving unit or a receiving module. A signal may be processed by a processing unit or a processing module. Other steps may be performed by an execution unit or a module, a generation unit or a module, an acquisition unit or a module, a shift unit or a module, a puncturing unit or a module, a decision unit or a module, a modification unit or a module, a reduction unit or a module, a removal unit or a module, or a selection unit or a module. Each unit or module may be hardware, software, or a combination thereof. For example, one or more of the units or modules may be an integrated circuit, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC).

[0214] The following references are relevant to the subject matter of this application and are incorporated herein by reference in their entirety: 3GPP TS 38.104, “NR; Base Station (BS) radio transmission and reception,” V17.4.0 (2021-12) 3GPP TS 38.213, “NR; Physical layer procedures for control,” V17.0.0 (2021-12) 3GPP TS 38.211, “NR; Physical channels and modulation,” V17.0.0 (2021-12) TR 38.817-01, “General aspects for User Equipment (UE) Radio Frequency (RF) for NR,” V16.3.0 (2021-09) RP-213603, “NR support for dedicated spectrum less than 5MHz for FR1”, RAN#94, Nokia, Dec. 6-17, 2021

[0215] Although the description has been set forth in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the present disclosure, as defined by the appended claims. Moreover, the scope of the present disclosure is not intended to be limited to the particular embodiments described herein. Those skilled in the art will readily appreciate from this disclosure that any now existing or hereafter developed process, machine, manufacture, composition of matter, means, method, or step may perform substantially the same function or achieve substantially the same result as the corresponding embodiment described herein. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

1. 1. A method comprising: receiving, by a user equipment (UE), from a base station, a punctured synchronization signal block (SSB) in a channel of a frequency band; the punctured SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a punctured PBCH derived from a first physical broadcast channel (PBCH) of a first SSB by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronization raster position; detecting, by the UE, the punctured SSB according to the first synchronization raster position; The method includes:

2. 2. The method of claim 1, wherein the punctured SSB has a bandwidth not greater than a bandwidth of the channel, and the first SSB has a bandwidth that exceeds a bandwidth of the channel.

3. The method according to claim 1 or 2, wherein the difference between the bandwidth of the first SSB and the bandwidth of the punctured SSB is related to the second number of RBs transmitted.

4. 4. The method of claim 1, further comprising: determining, by the UE, attributes of the channel based on a received punctured PBCH in the punctured SSB, the attributes including a starting frequency location of the channel.

5. The step of determining attributes of the channel comprises:

5. The method of claim 4, comprising determining, by the UE, a starting frequency location of the channel based on the received punctured PBCH, a center frequency of a PSS of the punctured SSB, and the first puncturing pattern.

6. The step of determining attributes of the channel comprises:

5. The method of claim 4, comprising determining, by the UE, a starting frequency location of the channel based on the received punctured PBCH, a frequency location of an RB occupied by the PSS of the punctured SSB, and an offset relative to the frequency location of the RB.

7. The method according to any one of claims 1 to 6, wherein the PSS of the first SSB has a centre frequency indicated by a second synchronization raster position of a second set of synchronization raster positions.

8. 8. The method of claim 7, wherein a frequency of the first set of synchronous raster positions is based on a first raster interval and a first set of shift intervals, and a frequency of the second set of synchronous raster positions is based on a second raster interval and a second set of shift intervals.

9. The method of claim 8 , wherein the first raster interval is different from the second raster interval, the first raster interval being related to a channel raster position of the channel.

10. 10. The method of claim 8 or 9, wherein the second raster interval is a multiple of the first raster interval.

11. The method according to any one of claims 8 to 10, wherein one or more shift intervals of the first set of shift intervals are different from one or more shift intervals of the second set of shift intervals.

12. The method of claim 7 , wherein the first set of synchronization raster positions is obtained by shifting the second set of synchronization raster positions in the frequency domain.

13. The method according to any one of claims 1 to 12, wherein the bandwidth of the channel is less than or equal to 5 MHz.

14. The method according to any one of claims 1 to 13, wherein the frequency span of the first SSB is 20 RBs.

15. The method according to any one of claims 1 to 14, wherein the first set of synchronization raster positions comprises a third synchronization raster position associated with a second puncture pattern.

16. 1. A method comprising: generating, by the base station, a punctured synchronization signal block (SSB) for a channel of the frequency band based on a first synchronization signal block (SSB) having a first bandwidth exceeding a second bandwidth of the channel; The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH derived from a first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronization raster position; transmitting, by the base station, the punctured SSB on the channel; The method includes:

17. 17. The method of claim 16, wherein the punctured SSB has a third bandwidth not greater than the second bandwidth of the channel.

18. 20. The method of claim 17, wherein a difference between a first bandwidth of the first SSB and a third bandwidth of the punctured SSB is related to the second number of RBs transmitted.

19. The method of any one of claims 16 to 18, wherein the punctured PBCH comprises information indicative of attributes of the channel, the attributes comprising a starting frequency position of the channel.

20. 20. The method of claim 19, wherein the starting frequency location of the channel is determinable based on the punctured PBCH, a center frequency of the PSS of the punctured SSB, and the first puncture pattern.

21. 20. The method of claim 19, wherein the starting frequency location of the channel is determinable based on the punctured PBCH, frequency locations of RBs occupied by the PSS of the punctured SSB, and an offset for the frequency locations of the RBs.

22. A method according to any one of claims 16 to 21, wherein the PSS of the first SSB has a centre frequency indicated by a second synchronization raster position of a second set of synchronization raster positions.

23. 23. The method of claim 22, wherein a frequency of the first set of synchronous raster positions is based on a first raster interval and a first set of shift intervals, and a frequency of the second set of synchronous raster positions is based on a second raster interval and a second set of shift intervals.

24. 24. The method of claim 23, wherein the first raster interval is different from the second raster interval, the first raster interval being related to a channel raster position of the channel.

25. 25. The method of claim 23 or 24, wherein the second raster interval is a multiple of the first raster interval.

26. The method according to any one of claims 23 to 25, wherein one or more shift intervals of the first set of shift intervals are different from one or more shift intervals of the second set of shift intervals.

27. 23. The method of claim 22, wherein the first set of synchronization raster positions is obtained by shifting the second set of synchronization raster positions in the frequency domain.

28. A method according to any one of claims 16 to 27, wherein the second bandwidth of the channel is less than or equal to 5 MHz.

29. The method according to any one of claims 16 to 28, wherein the frequency span of the first SSB is 20 RBs.

30. A method according to any one of claims 16 to 29, wherein the first set of synchronization raster positions comprises a third synchronization raster position associated with a second puncture pattern.

31. An apparatus comprising: a non-transitory memory store containing instructions; one or more processors in communication with said memory storage, said instructions, when executed by said one or more processors, cause said device to perform a method according to any one of claims 1 to 30; Including equipment.

32. A non-transitory computer readable medium storing computer instructions that, when executed by one or more processors, cause the one or more processors to perform the method of any one of claims 1 to 30.

33. 1. A system comprising: A base station (BS), A user equipment (UE) that communicates with the BS; Including, The BS is generating a punctured synchronization signal block (SSB) of a channel of a frequency band based on a first synchronization signal block (SSB) having a first bandwidth exceeding a second bandwidth of the channel, The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH of a first PBCH derived from the first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; the first puncture pattern is associated with the first synchronization raster position; and transmitting the punctured SSB on the channel; configured to execute The UE, receiving the punctured SSB on the channel; detecting the punctured SSB according to the first synchronization raster position; A system configured to execute the

34. An apparatus comprising:

1. A receiver module configured to receive, from a base station, a punctured primary synchronization signal block (SSB) for a channel of a frequency band, the receiver module comprising: The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes the PSS, the SSS, and a punctured PBCH derived from the first PBCH by applying a first puncturing pattern that reduces a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; the PSS of the punctured SSB has a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions configured for the frequency band; a receiver module, the first puncture pattern being associated with the first synchronization raster position; a detection module configured to detect the punctured SSB according to the first synchronization raster position; Including equipment.

35. An apparatus comprising: a generating module configured to generate a punctured synchronization signal block (SSB) of a channel of a frequency band based on a first synchronization signal block (SSB) having a first bandwidth exceeding a second bandwidth of the channel, The first SSB includes a first physical broadcast channel (PBCH), a primary synchronization signal (PSS), and a secondary synchronization signal (SSS); the punctured SSB includes a punctured PBCH, the PSS, and the SSS of a first PBCH, the punctured PBCH being derived from the first PBCH by applying a first puncturing pattern to reduce a first number of resource blocks (RBs) of the first PBCH to a second number of RBs for transmission; a PSS of the punctured SSB having a center frequency indicated by a first synchronization raster position of a set of first synchronization raster positions associated with the frequency band; a generating module, the first puncture pattern being associated with the first synchronization raster position; a transmitter module configured to transmit the punctured SSB on the channel; Including equipment.

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