Patent Description:
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. A wireless multiple-access communication system may include a number of base stations or access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).

Certain wireless communication systems may include a channel raster, which is generally the steps or frequencies within a channel that are available for communicating on. As one example, an LTE configured wireless communication system may include a channel raster of <NUM>. Traditionally, the channel raster is located at the center of the channel such that the channel raster is symmetric with respect to the resource blocks, e.g., there are the same number of resource blocks to the left and right of the channel raster. Some wireless communication systems may be configured to support intra-band contiguous carrier aggregation (CA) without having to insert a guardband (or gap) within the resource block grid. For example, the distance between two component carriers (CC)s may be a multiple of the channel raster granularity and the resource block size. This may present an issue when the resource block size varies (for example) and/or when other configurations move the channel raster away from the center of the channel.

[<NUM>-A] <NPL>) generally relates to channel raster design for NB-IoT, where differences between three operation modes are discussed. <NPL>) generally relates to NB-IoT - NB-MIB content and design, wherein operation mode indication, LTE CRS information and NB-RS information are discussed. <NPL>) generally relates to the discussion in defining channel raster and synchronization frequency raster. <NPL> discloses the decoupling between the frequency location of synchronization signals and the center of an NR carrier. Patent application publication <CIT> discloses that additional information defines a bandwidth adjustment for the standardized bandwidth that defines the non-standardized bandwidth.

The present invention is set out in the accompanying claims. In the following, each of the described methods, apparatuses, systems, examples and aspects which does not fully correspond to the invention as defined in the claims is thus not according to the invention and is, as well as the whole following description, present for illustration purposes only or to highlight specific aspects or features of the claims. The described techniques relate to improved methods, systems, devices, or apparatuses that identify communication channels or synchronization channels based on a channel raster or support channel and sync raster signaling. Generally, the described techniques provide methods for optimization of the channel/sync raster location or for signaling of the channel raster, channel resource usage in relation to the channel raster, and location information to a device in the situation where the channel raster is not located at the center of the channel, e.g., when the resource blocks are asymmetric with respect to the channel raster. Generally, references to the resource blocks being asymmetric with respect to the channel raster, or vice versa, refer to the channel raster being offset from the center of the channel such that there is not an equal number of resource blocks on both sides of the channel raster, e.g., the number of resource blocks to the left and to the right of the channel raster are different. Accordingly, in some aspects the network (e.g., a base station communicating with a user equipment (UE)) may select, determine, or otherwise identify that the channel raster is not centered on the channel (e.g., a component carrier (CC)) and transmit information indicative of the channel raster and also information indicative of the location of the resource blocks in relation to the channel raster (e.g., a first resource block, an offset for the first resource block relative to the channel raster (in frequency, number of resource blocks, number of subcarriers, and the like)). The network may identify the channel raster offset information on a per channel basis and/or on a per UE basis. The network may also transmit the indication on a per channel basis (e.g., broadcast to all devices) and/or on a per UE basis (e.g., unicast transmission to a particular UE). Moreover, the channel raster offset information may be associated with uplink and/or downlink channels.

Aspects of the disclosure are initially described in the context of a wireless communications system. Certain wireless communication systems may be configured to support signaling channel raster and synchronization information between devices. For example, a channel (e.g., a component carrier (CC)) may have a channel raster that is not centered on the channel. Since the channel raster is not centered on the channel, the channel raster is asymmetric with respect to the resource blocks, or vice versa, e.g., there are more resource blocks on one side of the channel raster than on the other side. Accordingly, a network device (e.g., a base station) may identify the non-centered channel raster for the channel and configure a message to carry or otherwise provide an indication of the channel raster and, also, location information for the first resource block. The location information may provide for the receiving device to find the first resource block, e.g., exact location in frequency, relative location with respect to the total number of resource blocks, and the like. The receiving device may receive the message with the indication and use the indication to identify the channel raster for the channel and the location of the first resource block. The channel may be an uplink channel and/or a downlink channel. In some aspects, the network device may configure the channel raster for the channel based on the user equipment's (UE's) capabilities. The network device may transmit the indication in a broadcast message and/or a unicast message. Accordingly, the network device may support use of offset channel raster(s) and related signaling mechanisms to support communications.

Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to channel and sync raster signaling.

<FIG> illustrates an example of a wireless communication system <NUM> in accordance with various aspects of the present disclosure. The wireless communication system <NUM> includes base stations <NUM>, UEs <NUM>, and a core network <NUM>. In some examples, the wireless communication system <NUM> may be a Long Term Evolution (LTE), LTE-Advanced (LTE-A) network, or a New Radio (NR) network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (i.e., mission critical) communications, low latency communications, and communications with low-cost and low-complexity devices.

Each base station <NUM> may provide communication coverage for a respective geographic coverage area <NUM>. Control information and data may be multiplexed on an uplink channel or a downlink channel according to various techniques. Control information and data may be multiplexed on a downlink channel, for example, using time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. In some examples, the control information transmitted during a transmission time interval (TTI) of a downlink channel may be distributed between different control regions in a cascaded manner (e.g., between a common control region and one or more UE-specific control regions).

UEs <NUM> may be dispersed throughout the wireless communication system <NUM>, and each UE <NUM> may be stationary or mobile. A UE <NUM> may also be referred to as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. A UE <NUM> may also be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a personal electronic device, a handheld device, a personal computer, a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, a machine type communication (MTC) device, an appliance, an automobile, or the like.

In some cases, an MTC device may operate using half-duplex (one-way) communications at a reduced peak rate. MTC devices may also be configured to enter a power saving "deep sleep" mode when not engaging in active communications. In some cases, MTC or IoT devices may be designed to support mission critical functions and wireless communications system may be configured to provide ultra-reliable communications for these functions.

The core network <NUM> may provide user authentication, access authorization, tracking, IP connectivity, and other access, routing, or mobility functions. At least some of the network devices, such as base station <NUM>, may include subcomponents such as an access network entity, which may be an example of an access node controller (ANC). Each access network entity may communicate with a number of UEs <NUM> through a number of other access network transmission entities, each of which may be an example of a smart radio head, or a transmission/reception point (TRP).

Wireless communication system <NUM> may operate in an ultra-high frequency (UHF) frequency region using frequency bands from <NUM> to <NUM> (<NUM>), although some networks (e.g., a wireless local area network (WLAN)) may use frequencies as high as <NUM>. This region may also be known as the decimeter band, since the wavelengths range from approximately one decimeter to one meter in length. UHF waves may propagate mainly by line of sight, and may be blocked by buildings and environmental features. However, the waves may penetrate walls sufficiently to provide service to UEs <NUM> located indoors. Transmission of UHF waves is characterized by smaller antennas and shorter range (e.g., less than <NUM>) compared to transmission using the smaller frequencies (and longer waves) of the high frequency (HF) or very high frequency (VHF) portion of the spectrum. In some cases, wireless communication system <NUM> may also utilize extremely high frequency (EHF) portions of the spectrum (e.g., from <NUM> to <NUM>). This region may also be known as the millimeter band, since the wavelengths range from approximately one millimeter to one centimeter in length. Thus, EHF antennas may be even smaller and more closely spaced than UHF antennas. In some cases, this may facilitate use of antenna arrays within a UE <NUM> (e.g., for directional beamforming). However, EHF transmissions may be subject to even greater atmospheric attenuation and shorter range than UHF transmissions.

Thus, wireless communication system <NUM> may support millimeter wave (mmW) communications between UEs <NUM> and base stations <NUM>. Devices operating in mmW or EHF bands may have multiple antennas to allow beamforming. That is, a base station <NUM> may use multiple antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>. Beamforming (which may also be referred to as spatial filtering or directional transmission) is a signal processing technique that may be used at a transmitter (e.g., a base station <NUM>) to shape and/or steer an overall antenna beam in the direction of a target receiver (e.g., a UE <NUM>). This may be achieved by combining elements in an antenna array in such a way that transmitted signals at particular angles experience constructive interference while others experience destructive interference.

Multiple-input multiple-output (MIMO) wireless systems use a transmission scheme between a transmitter (e.g., a base station <NUM>) and a receiver (e.g., a UE <NUM>), where both transmitter and receiver are equipped with multiple antennas. Some portions of wireless communication system <NUM> may use beamforming. For example, base station <NUM> may have an antenna array with a number of rows and columns of antenna ports that the base station <NUM> may use for beamforming in its communication with UE <NUM>. Signals may be transmitted multiple times in different directions (e.g., each transmission may be beamformed differently). A mmW receiver (e.g., a UE <NUM>) may try multiple beams (e.g., antenna subarrays) while receiving the synchronization signals.

In some cases, the antennas of a base station <NUM> or UE <NUM> may be located within one or more antenna arrays, which may support beamforming or MIMO operation. One or more base station antennas or antenna arrays may be collocated at an antenna assembly, such as an antenna tower. A base station <NUM> may multiple use antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>.

In some cases, wireless communication system <NUM> may be a packet-based network that operate according to a layered protocol stack. The MAC layer may also use Hybrid ARQ (HARQ) to provide retransmission at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE <NUM> and a network device, or core network <NUM> supporting radio bearers for user plane data.

Time intervals in LTE or NR may be expressed in multiples of a basic time unit (which may be a sampling period of Ts= <NUM>/<NUM>,<NUM>,<NUM> seconds). Time resources may be organized according to radio frames of length of <NUM> (Tf = 307200Ts), which may be identified by a system frame number (SFN) ranging from <NUM> to <NUM>. Each frame may include ten <NUM> subframes numbered from <NUM> to <NUM>. A subframe may be further divided into two. <NUM> slots, each of which contains <NUM> or <NUM> modulation symbol periods (depending on the length of the cyclic prefix prepended to each symbol). Excluding the cyclic prefix, each symbol contains <NUM> sample periods. In some cases the subframe may be the smallest scheduling unit, also known as a TTI. In other cases, a TTI may be shorter than a subframe or may be dynamically selected (e.g., in short TTI bursts or in selected component carriers using short TTIs).

A resource element may consist of one symbol period and one subcarrier (e.g., a <NUM> frequency range). A resource block may contain <NUM> consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each OFDM symbol, <NUM> consecutive OFDM symbols in the time domain (<NUM> slot), or <NUM> resource elements. The number of bits carried by each resource element may depend on the modulation scheme (the configuration of symbols that may be selected during each symbol period). Thus, the more resource blocks that a UE receives and the higher the modulation scheme, the higher the data rate may be.

Wireless communication system <NUM> may support operation on multiple cells or carriers, a feature which may be referred to as CA or multi-carrier operation. A carrier may also be referred to as a CC, a layer, a channel, etc. The terms "carrier," "component carrier," "cell," and "channel" may be used interchangeably herein. A UE <NUM> may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation.

In some cases, wireless communication system <NUM> may utilize enhanced component carriers (eCCs). An eCC may be characterized by one or more features including: wider bandwidth, shorter symbol duration, shorter TTIs, and modified control channel configuration. An eCC may also be configured for use in unlicensed spectrum or shared spectrum (where more than one operator is allowed to use the spectrum). An eCC characterized by wide bandwidth may include one or more segments that may be utilized by UEs <NUM> that are not capable of monitoring the whole bandwidth or prefer to use a limited bandwidth (e.g., to conserve power).

A shorter symbol duration is associated with increased subcarrier spacing. A device, such as a UE <NUM> or base station <NUM>, utilizing eCCs may transmit wideband signals (e.g., <NUM>, <NUM>, <NUM>, <NUM>, etc.) at reduced symbol durations (e.g., <NUM> microseconds). A TTI in eCC may consist of one or multiple symbols. In some cases, the TTI duration (that is, the number of symbols in a TTI) may be variable.

A shared radio frequency spectrum band may be utilized in an NR shared spectrum system. For example, an NR shared spectrum may utilize any combination of licensed, shared, and unlicensed spectrums, among others. The flexibility of eCC symbol duration and subcarrier spacing may allow for the use of eCC across multiple spectrums. In some examples, NR shared spectrum may increase spectrum utilization and spectral efficiency, specifically through dynamic vertical (e.g., across frequency) and horizontal (e.g., across time) sharing of resources.

In some cases, wireless communication system <NUM> may utilize both licensed and unlicensed radio frequency spectrum bands. For example, wireless communication system <NUM> may employ LTE License Assisted Access (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NR technology in an unlicensed band such as the <NUM> Industrial, Scientific, and Medical (ISM) band. When operating in unlicensed radio frequency spectrum bands, wireless devices such as base stations <NUM> and UEs <NUM> may employ listen-before-talk (LBT) procedures to ensure the channel is clear before transmitting data. In some cases, operations in unlicensed bands may be based on a CA configuration in conjunction with CCs operating in a licensed band. Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, or both. Duplexing in unlicensed spectrum may be based on frequency division duplexing (FDD), time division duplexing (TDD) or a combination of both.

In some cases, wireless communication system <NUM> may support intra-band contiguous CA without guard band. The distance between two CCs may be a multiple of the channel raster granularity and the resource block size. In CA without guard band, all the spectrum can be filled with resource blocks. In CA with guard band, not all of the spectrum can be filled with RBs so there will be some spectrum that is not used, e.g., gaps.

In some aspects, CCs may refer to the CCs that are on the same subcarrier grid or on the same resource block grid. The same subcarrier grid may indicate that the subcarriers from all CCs can be processed by the same fast Fourier transform (FFT) so that the distance between channel rasters of the CCs is a common multiple of channel raster spacing and subcarrier spacing. For example, a channel raster of <NUM> and subcarrier spacing (SCS) of <NUM> may lead to a spacing between CCs that are multiples of <NUM>. This may result in the space between CCs being a multiple of SCS but not a multiple of <NUM> x SCS, which may be a resource block. When the system cannot allocate fractional RBs, there may be some subcarriers that cannot be allocated (scheduled). The same resource block grid may indicate that the subcarriers from all CCs can be processed by the same FFT and, additionally, all of the space between the CCs can be filled up with resource blocks. This may result in the distance between the channel rasters of the CCs being a common multiple of channel raster granularity and resource block size. For example, with <NUM> channel raster and resource block size of <NUM> (e.g., <NUM> SCS with 12subcarriers in each resource block), the distance between the channel raster is a multiple of <NUM>. To support intra-band contiguous CA without any guardband, the CCs may be on the same resource block grid.

In some aspects, wireless communication system <NUM> may support one wideband channel being treated as a single channel by some UEs <NUM> and as intra-band contiguous CA by other UEs <NUM>. As one example with one <NUM> channel, the <NUM> channel may be composed of two channels of <NUM> each, e.g., CC1 and CC2. In some aspects, UE <NUM> may access either CC1 or CC2 (e.g., UEs that are capable of <NUM> total bandwidth). In some aspects, UE <NUM> may access the entire <NUM> channel as one single channel (e.g., UEs that are capable of <NUM> total bandwidth). In some aspects, UE <NUM> may access the <NUM> channel as 2x100MHz CA (e.g., UEs that are capable of <NUM> total bandwidth and do CA).

In some aspects, wireless communication system <NUM> may support all such UEs <NUM> and maximize spectrum utilization where all three channels (e.g., the <NUM> channel and/or CC1/CC2) are on the same resource block grid. For example, using a <NUM> channel raster granularity and a <NUM> SCS, CC2 channel raster would be <NUM> and <NUM> whereas the CC1 channel raster would be on <NUM> or <NUM>. This means that the channel raster will not be situated in the center of the CC1 and CC2 channels. That is, in the example above, in order to place the raster of the <NUM> at the center, the channel raster of CC1 and CC2 may be shifted (left or right). Even if the channel raster of the <NUM> channel is in the center, the raster of CC1 and CC2 may not be in the center of their own channels anymore. That is, the channel raster may not be in the center of the CC anymore so the number of resource blocks to the left and to the right of the channel raster will be different.

In some aspects, wireless communication system <NUM> may support signaling the location of the resource blocks in relation to the channel raster to the UE <NUM> so that the UE <NUM> knows where the allocated resource blocks are. For the same channel raster entry, wireless communication system <NUM> may have different offsets (e.g., varying) of resource block allocations. For example, a base station <NUM> may identify a channel raster associated with a plurality of resource blocks of a channel, the plurality of resource blocks having an asymmetric relation with respect to the channel raster. The base station <NUM> may configure, based at least in part on the asymmetric relation, a message to indicate a resource block offset metric that comprises an indication of the channel raster and location information associated with a first resource block of the plurality of resource blocks. The base station <NUM> may transmit the message to convey the indication of the resource block offset metric. A UE <NUM> may receive the message that comprises the indication of a resource block offset metric and identify, based at least in part on the resource block offset metric, a channel raster associated with a plurality of resource blocks of a channel, the plurality of resource blocks having an asymmetric relation with respect to the channel raster.

<FIG> illustrates an example of a process <NUM> that supports channel and sync raster signaling in accordance with various aspects of the present disclosure. In some examples, process <NUM> may implement aspects of wireless communication system <NUM>. Process <NUM> may include a base station <NUM> and a UE <NUM>, which may be examples of the corresponding devices described herein. Generally, process <NUM> illustrates one example where base station <NUM> signals an indication to UE <NUM> of the channel raster and location information for the first resource block when the channel raster is not centered in the channel.

At <NUM>, base station <NUM> may identify a channel raster. The channel raster may be associated with a plurality of resource blocks of the channel. The resource blocks may be asymmetrical with respect to the channel raster, e.g., there may be more resource blocks on one side of the channel raster than there are on the other side. The asymmetric relation may indicate that the channel raster is offset from the middle of the channel. The channel may be an uplink channel and/or a downlink channel. The channel may be a CC channel, in some examples.

At <NUM>, base station <NUM> may configure a message to provide an indication of the channel raster and location information. For example, base station <NUM> may configure the message to carry or otherwise convey an indication of a resource block offset metric that includes the indication of the channel raster and the location information. The location information may be associated with a first resource block and may provide information supporting the UE <NUM> being able to locate the first resource block.

In some aspects, the location information may include an offset for the first resource block relative to the channel raster, e.g., in terms of an absolute frequency, a number of resource blocks, a number of subcarriers, etc. For example, base station <NUM> may, based on the asymmetric relation, identify an offset distance (e.g., frequency offset, resource block count offset, etc.) between the first resource block and the channel raster. The location information may include the offset distance. Base station <NUM> may, based on the asymmetric relation, identify a frequency associated with the first resource block, e.g., an absolute frequency or carrier of the first resource block. The location information may include the frequency associated with the first resource block. Base station <NUM> may identify a resource block count associated with the resource blocks, e.g., a number of contiguous resource blocks. The location may include the resource block count. In some aspects, the location information may include the frequency of the first resource block and the resource block count.

In some aspects, base station <NUM> may select the channel raster for the channel based on the capability of UE <NUM>. For example, base station <NUM> may identify the UE capability (e.g., supported bandwidth, CA support, etc.) and identify or otherwise select the channel raster for UE <NUM> based on the supported capability (e.g., UE-specific). Moreover, base station <NUM> may use a signaling scheme for the message based on the capability of UE <NUM>, e.g., broadcast vs unicast signaling, signaling channel, etc..

In some aspects, the plurality of resource blocks may have gaps (e.g., unused resource blocks, resource elements, etc.). For example, depending on how the channel raster is defined it may not be possible to fill up the entire spectrum between two CCs. For example, a <NUM> CC which is an aggregation of two <NUM> channels may have some subcarriers (resource elements) in the center that cannot be used. In the example of a <NUM> CC there may be some resource elements around the center that could not be used. Where exactly these resource blocks are located may be signaled to UE <NUM>. If there is a gap in frequency in the resource elements that are allocated to UE <NUM>, base station <NUM> may signal this information to UE <NUM>. The signaling may include the number of resource elements that are not used, the location of the contiguous resource blocks that are in use, and the like. When multiple channels are aggregated (e.g. <NUM> channel is an aggregation of two <NUM> or four <NUM> channels, there could be multiple "holes" or gaps), the location of all these holes may be aggregated. In some aspects, base station <NUM> may broadcast which resource elements are not used in the wider channel. In some aspects, base station <NUM> may configure UEs with resource elements that are not used. In some aspects, base station may broadcast the start and length of each contiguous block of resource blocks. In some aspects, base station <NUM> may configure UEs individually with different blocks of contiguous resource blocks.

Accordingly, base station <NUM> may identify which resource blocks are unused and configure the message to indicate location parameter(s) associated with the unused resource blocks. The location parameter(s) may include, but are not limited to, an identifier of the unused resource blocks, the first resource block and a resource block count for contiguous resource blocks, and the like.

At <NUM>, base station <NUM> may transmit (and UE <NUM> may receive) the message that carries or otherwise conveys the indication of the resource block offset metric. The message may be broadcast to all UEs and/or unicast to a particular UE, e.g., UE <NUM>.

In some aspects, base station <NUM> may broadcast the relation between the channel raster entry and the resource block locations. This may be an offset for the edge resource block (the first resource block) relative to the channel raster (e.g., in absolute frequency or number of resource blocks or number of subcarriers). In some aspects, base station <NUM> may broadcast an absolute frequency such that UE <NUM> may locate the resource blocks that are used in the channel, e.g., an absolute frequency of the edge resource block in Hz.

In some aspects, base station <NUM> may configure UE <NUM> with the specific resource block location. This may be an offset for the edge resource block relative to the channel raster (e.g., in absolute frequency or number of resource blocks or number of subcarriers). This may be an absolute frequency or an absolute frequency offset (in Hz) from the channel raster. The specific resource block location may be based on UE <NUM> capabilities that are signaled to the network, e.g., the radio frequency (RF) capabilities of UE <NUM>.

In some aspects, base station <NUM> may signal where the channel raster for an uplink channel is located and where the resource blocks are used in the uplink channel (e.g., even for a TDD configured system, the uplink and/or downlink raster or resource block location may be different). The channel raster configuration may be common for the channel (e.g., channel specific). Base station <NUM> may broadcast the uplink channel raster as an absolute frequency and the offset of the edge resource block relative to the channel raster. In some aspects, the channel raster may define a set of radio frequency (RF) reference frequencies that are used to identify the RF channel position. The RF reference frequency for an RF channel may map to a resource element on the carrier. In some aspects, the mapping may be determined based on the total number of resource blocks that are allocated in the channel and apply to both uplink and downlink. In some aspects, the RF reference frequency in the uplink and/or downlink may be designated in a NR Absolute Radio Frequency Channel Number (NR-ARFCN) in a defined range on the global frequency raster.

Base station <NUM> may broadcast the absolute frequency of the edge resource block and the number of resource blocks to be used. This may be any frequency or from a set of allowed frequencies. The channel raster configuration may be configured per UE (e.g., UE-specific). Base station <NUM> may configure each UE with the uplink channel raster as an absolute frequency and the offset of the edge resource block relative to the raster. Base station <NUM> may configure each UE with the absolute frequency of the edge resource block and the number of resource blocks to be used. This may be any frequency or from a set of allowed frequencies.

At <NUM>, UE <NUM> may identify the channel raster using the resource block offset metric. For example, UE <NUM> may decode the message received from base station <NUM> and identify the channel raster associated with the resource blocks of the channel. UE <NUM> may identify the location information that is also indicated in the message. Accordingly, UE <NUM> may use the message to identify the channel raster offset metric for the channel and/or for a plurality of channels. The channel(s) may be uplink and/or downlink channels.

<FIG> illustrates an example of a channel raster offset configuration <NUM> that supports channel and sync raster signaling in accordance with various aspects of the present disclosure. In some examples, channel raster offset configuration <NUM> may implement aspects of wireless communication system <NUM> and/or process <NUM>.

Generally, channel raster offset configuration <NUM> illustrates three resource block grids <NUM> (with only one being labeled). Each resource block grid <NUM> includes a plurality of resource blocks <NUM>. Although channel raster offset configuration <NUM> illustrates each resource block grid <NUM> as having <NUM> resource blocks <NUM>, it is to be understood that each (or all) of the resource block grids <NUM> may have more or fewer resource blocks <NUM>.

Channel raster offset configuration <NUM> illustrates three examples of a channel raster that is not centered on the channel. For example, the first channel raster offset (Offset <NUM>) may include a resource block <NUM> where the channel raster is located at resource block <NUM>. This may result in the resource blocks <NUM> having an asymmetric relation with respect to the channel raster, e.g., <NUM> resource blocks <NUM> to the right of the channel raster and <NUM> resource blocks <NUM> to the left of the channel raster. Similarly, the second channel raster offset (Offset <NUM>) may include a channel raster that is at resource block <NUM>. This also results in the resource blocks <NUM> having an asymmetric relation with respect to the channel raster, e.g., <NUM> resource blocks <NUM> to the right and <NUM> resource blocks <NUM> to the left of the channel raster.

In some aspects, the different channel raster offsets are based on a channel. For example, Offset <NUM> may be associated with a first channel, Offset <NUM> may be associated with a second channel, and Offset <NUM> may be associated with a third channel. In some aspects, the different channel raster offsets are based on a UE. For example, Offset <NUM> may be associated with a first UE, Offset <NUM> may be associated with a second UE, and Offset <NUM> may be associated with a third UE. In some aspects, the different channel raster offsets may be associated with different UEs and different channels.

<FIG> illustrates an example of a synchronization raster configuration <NUM> that supports channel and sync raster signaling in accordance with various aspects of the present disclosure. In some examples, synchronization raster configuration <NUM> may implement aspects of wireless communication system <NUM>, process <NUM>, and/or channel raster offset configuration <NUM>.

Generally, synchronization raster configuration <NUM> illustrates a frequency band <NUM> that forms a first channel <NUM> and a second channel <NUM>. Each of the first channel <NUM> and second channel <NUM> may have an associated minimum bandwidth that occupies some, but not all, of the frequency band <NUM>. A base station may transmit a synchronization signal <NUM> that covers, at least in some aspects, portions of both the first channel <NUM> and the second channel <NUM>. For example, the base station may identify a synchronization raster offset between the first channel <NUM> and the second channel <NUM> of the frequency band <NUM>. The first channel <NUM> and the second channel <NUM> may share a common resource block grid, e.g., the resource blocks may be aligned in some aspects between the first and second channels. In some aspects, the base station may transmit a synchronization signal <NUM> on each resource block entry of the common resource block grid that is between the synchronization offset. In some aspects, the base station may transmit a synchronization signal on each channel raster entry that is between two entries that are on the common resource grid.

In some aspects, a synchronization signal <NUM> may not sit in the middle of the channel, but may still be located on the channel raster. Different channels within a band can share the same synchronization burst location (e.g., primary synchronization signal (PSS), secondary synchronization signal (SSS)). For example, the first instance of the first channel <NUM> and the first instance of the second channel <NUM> may use the same sync burst block, e.g., synchronization signal <NUM>. The same sync burst block may be used for the channel presented in the dotted line (e.g., a channel shifted one resource block).

In some aspects, the sync burst locations in frequency band <NUM> may be down selected from the channel raster based on the relationship (X+<NUM>-Y RBs). In some aspects, this may be the maximum spacing between sync raster entries. To support different channels using the same sync burst location, the channels may be on the same resource block grid. If the channel raster is not a multiple of the resource block size, all the channel raster entries between two resource block grid offsets may also be supported. For example, with a <NUM> channel raster and a <NUM> resource block size, the resource block grid may be <NUM>. The sync raster may have <NUM> to <NUM> entries to cover all the channels that have raster offsets of <NUM> between <NUM> and <NUM> (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) which is the next entry on the same resource block grid as <NUM>.

In some aspects, a UE may search for synchronization signal(s) <NUM> on each channel raster entry that is between two entries that are on the resource block grid for each sync channel entry. For example, if the sync raster distance is <NUM> (<NUM>, <NUM>, <NUM>, etc.) the UE may search also on <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and also on <NUM>, <NUM>, <NUM>, <NUM> ,<NUM>, <NUM>, <NUM>, <NUM>, etc..

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a base station <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, base station communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

Receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to channel and sync raster signaling, etc.). Information may be passed on to other components of the device. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

Base station communications manager <NUM> may be an example of aspects of the base station communications manager <NUM> described with reference to <FIG>.

Base station communications manager <NUM> and/or at least some of its various sub-components may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions of the base station communications manager <NUM> and/or at least some of its various sub-components may be executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure. The base station communications manager <NUM> and/or at least some of its various sub-components may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical devices. In some examples, base station communications manager <NUM> and/or at least some of its various sub-components may be a separate and distinct component in accordance with various aspects of the present disclosure. In other examples, base station communications manager <NUM> and/or at least some of its various sub-components may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

Base station communications manager <NUM> may identify a channel raster associated with a set of resource blocks of a channel, the set of resource blocks having an asymmetric relation with respect to the channel raster. Base station communications manager <NUM> may configure, based on the asymmetric relation, a message to indicate a resource block offset metric that includes an indication of the channel raster and location information associated with a first resource block of the set of resource blocks. Base station communications manager <NUM> may transmit the message to convey the indication of the resource block offset metric.

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a wireless device <NUM> or a base station <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, base station communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

Base station communications manager <NUM> may be an example of aspects of the base station communications manager <NUM> described with reference to <FIG>. Base station communications manager <NUM> may also include channel raster identification manager <NUM>, channel raster indication manager <NUM>, and channel raster communication manager <NUM>.

Channel raster identification manager <NUM> may identify a channel raster associated with a set of resource blocks of a channel, the set of resource blocks having an asymmetric relation with respect to the channel raster. In some cases, the channel is associated with at least one of an uplink channel, a downlink channel, or combinations thereof.

Channel raster indication manager <NUM> may configure, based on the asymmetric relation, a message to indicate a resource block offset metric that includes an indication of the channel raster and location information associated with a first resource block of the set of resource blocks.

Channel raster communication manager <NUM> may transmit the message to convey the indication of the resource block offset metric. In some cases, the message includes at least one of a broadcast message, a UE specific message, or combinations thereof.

<FIG> shows a block diagram <NUM> of a base station communications manager <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. The base station communications manager <NUM> may be an example of aspects of a base station communications manager <NUM>, a base station communications manager <NUM>, or a base station communications manager <NUM> described with reference to <FIG>, <FIG>, and <FIG>. The base station communications manager <NUM> may include channel raster identification manager <NUM>, channel raster indication manager <NUM>, channel raster communication manager <NUM>, offset manager <NUM>, capability manager <NUM>, gap manager <NUM>, and raster offset manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

Offset manager <NUM> may identify, based on the asymmetric relation, an offset distance between the first resource block and the channel raster, where the location information includes the offset distance. Offset manager <NUM> may identify, based on the asymmetric relation, a frequency associated with the first resource block, where the location information includes the frequency. Offset manager <NUM> may identify, based on the asymmetric relation, a resource block count associated with the set of resource blocks, where the location information includes the resource block count. In some cases, the offset distance includes at least one of a frequency offset or a resource block count offset.

Capability manager <NUM> may identify a UE capability and identify the channel raster based on the UE capability. Capability manager <NUM> may select, based on the UE capability, a signaling scheme to convey the indication of the resource block offset metric.

Gap manager <NUM> may identify one or more unused resource blocks in the set of resource blocks and configure, based on the one or more unused resource blocks, the message to indicate a location parameter associated with the one or more unused resource blocks. In some cases, the location parameter includes at least one of an identifier associated with the one or more unused resource blocks, the first resource block and a resource block count associated with contiguous resource blocks, or combinations thereof. In some cases, each of the one or more unused resource blocks include a resource block with a predetermined number of unallocated resource elements.

Raster offset manager <NUM> may identify a synchronization raster offset between a first channel and a second channel of a band, the first channel and the second channel sharing a common resource block grid. Raster offset manager <NUM> may transmit a synchronization signal on each resource block entry of the common resource block grid that is between the synchronization raster offset. Raster offset manager <NUM> may transmit a synchronization signal on each channel raster entry that is between two entries that are on the common resource block grid. In some cases, the synchronization raster offset includes a <NUM> raster offset and each resource block entry is located at <NUM> increments.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Device <NUM> may be an example of or include the components of wireless device <NUM>, wireless device <NUM>, or a base station <NUM> as described herein. Device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including base station communications manager <NUM>, processor <NUM>, memory <NUM>, software <NUM>, transceiver <NUM>, antenna <NUM>, network communications manager <NUM>, and inter-station communications manager <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>). Device <NUM> may communicate wirelessly with one or more UEs <NUM>.

Processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a central processing unit (CPU), a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into processor <NUM>. Processor <NUM> may be configured to execute computer-readable instructions stored in a memory to perform various functions (e.g., functions or tasks supporting channel and sync raster signaling).

Software <NUM> may include code to implement aspects of the present disclosure, including code to support channel and sync raster signaling. Software <NUM> may be stored in a non-transitory computer-readable medium such as system memory or other memory. In some cases, the software <NUM> may not be directly executable by the processor but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

Inter-station communications manager <NUM> may manage communications with other base station <NUM>, and may include a controller or scheduler for controlling communications with UEs <NUM> in cooperation with other base stations <NUM>. In some examples, inter-station communications manager <NUM> may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between base stations <NUM>.

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a UE <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, UE communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

UE communications manager <NUM> may be an example of aspects of the UE communications manager <NUM> described with reference to <FIG>.

UE communications manager <NUM> and/or at least some of its various sub-components may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions of the UE communications manager <NUM> and/or at least some of its various sub-components may be executed by a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure. The UE communications manager <NUM> and/or at least some of its various sub-components may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical devices. In some examples, UE communications manager <NUM> and/or at least some of its various sub-components may be a separate and distinct component in accordance with various aspects of the present disclosure. In other examples, UE communications manager <NUM> and/or at least some of its various sub-components may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

UE communications manager <NUM> may receive a message that includes an indication of a resource block offset metric and identify, based on the resource block offset metric, a channel raster associated with a set of resource blocks of a channel, the set of resource blocks having an asymmetric relation with respect to the channel raster.

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a wireless device <NUM> or a UE <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, UE communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

UE communications manager <NUM> may be an example of aspects of the UE communications manager <NUM> described with reference to <FIG>. UE communications manager <NUM> may also include channel raster communication manager <NUM> and channel raster identification manager <NUM>.

Channel raster communication manager <NUM> may receive a message that includes an indication of a resource block offset metric. In some cases, the message includes at least one of a broadcast message, a UE specific message, or combinations thereof.

Channel raster identification manager <NUM> may identify, based on the resource block offset metric, a channel raster associated with a set of resource blocks of a channel, the set of resource blocks having an asymmetric relation with respect to the channel raster.

<FIG> shows a block diagram <NUM> of a UE communications manager <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. The UE communications manager <NUM> may be an example of aspects of a UE communications manager <NUM> described with reference to <FIG>, <FIG>, and <FIG>. The UE communications manager <NUM> may include channel raster communication manager <NUM>, channel raster identification manager <NUM>, offset manager <NUM>, gap manager <NUM>, and raster offset manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

Offset manager <NUM> may identify, based on the asymmetric relation, an offset distance between the first resource block and the channel raster, where the resource block offset metric includes the offset distance. Offset manager <NUM> may identify, based on the asymmetric relation, a frequency associated with the first resource block, where the resource block offset metric includes the frequency. Offset manager <NUM> may identify, based on the asymmetric relation, a resource block count associated with the set of resource blocks, where the resource block offset metric includes the resource block count. In some cases, the offset distance includes at least one of a frequency offset or a resource block count offset.

Gap manager <NUM> may determine, based on the message, that there are one or more unused resource blocks in the set of resource blocks and identify, based on the message, a location parameter associated with the one or more unused resource blocks. In some cases, the location parameter includes at least one of an identifier associated with the one or more unused resource blocks, the first resource block and a resource block count associated with contiguous resource blocks, or combinations thereof. In some cases, each of the one or more unused resource blocks include a resource block with a predetermined number of unallocated resource elements.

Raster offset manager <NUM> may identify, based on the message, a synchronization raster offset between a first channel and a second channel of a band, the first channel and the second channel sharing a common resource block grid. Raster offset manager <NUM> may monitor for a synchronization signal on each resource block entry of the common resource block grid that is between the synchronization raster offset. Raster offset manager <NUM> may monitor for a synchronization signal on each channel raster entry that is between two entries that are on the common resource block grid. In some cases, the synchronization raster offset includes a <NUM> raster offset.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports channel and sync raster signaling in accordance with aspects of the present disclosure. Device <NUM> may be an example of or include the components of UE <NUM> as described herein. Device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including UE communications manager <NUM>, processor <NUM>, memory <NUM>, software <NUM>, transceiver <NUM>, antenna <NUM>, and I/O controller <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>). Device <NUM> may communicate wirelessly with one or more base stations <NUM>.

Processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into processor <NUM>. Processor <NUM> may be configured to execute computer-readable instructions stored in a memory to perform various functions (e.g., functions or tasks supporting channel and sync raster signaling).

<FIG> shows a flowchart illustrating a method <NUM> for channel and sync raster signaling in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a base station <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a base station communications manager as described with reference to <FIG>. In some examples, a base station <NUM> may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the base station <NUM> may perform aspects of the functions described below using special-purpose hardware.

At block <NUM> the base station <NUM> may identify a channel raster associated with a plurality of resource blocks of a channel, the plurality of resource blocks having an asymmetric relation with respect to the channel raster. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a channel raster identification manager as described with reference to <FIG>.

At block <NUM> the base station <NUM> may configure, based at least in part on the asymmetric relation, a message to indicate a resource block offset metric that comprises an indication of the channel raster and location information associated with a first resource block of the plurality of resource blocks. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a channel raster indication manager as described with reference to <FIG>.

At block <NUM> the base station <NUM> may transmit the message to convey the indication of the resource block offset metric. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a channel raster communication manager as described with reference to <FIG>.

At block <NUM> the base station <NUM> may identify one or more unused resource blocks in the plurality of resource blocks. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a gap manager as described with reference to <FIG>.

At block <NUM> the base station <NUM> may configure, based at least in part on the one or more unused resource blocks, the message to indicate a location parameter associated with the one or more unused resource blocks. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a gap manager as described with reference to <FIG>.

<FIG> shows a flowchart illustrating a method <NUM> for channel and sync raster signaling in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a UE communications manager as described with reference to <FIG>. In some examples, a UE <NUM> may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the UE <NUM> may perform aspects of the functions described below using special-purpose hardware.

At block <NUM> the UE <NUM> may receive a message that comprises an indication of a resource block offset metric. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a channel raster communication manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may identify, based at least in part on the resource block offset metric, a channel raster associated with a plurality of resource blocks of a channel, the plurality of resource blocks having an asymmetric relation with respect to the channel raster. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a channel raster identification manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may identify, based at least in part on the asymmetric relation, an offset distance between the first resource block and the channel raster, wherein the resource block offset metric comprises the offset distance. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a offset manager as described with reference to <FIG>.

The terms "system" and "network" are often used interchangeably. A code division multiple access (CDMA) system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-<NUM>, IS-<NUM>, and IS-<NUM> standards.

In LTE/LTE-A networks, including such networks described herein, the term evolved node B (eNB) may be generally used to describe the base stations. The wireless communications system or systems described herein may include a heterogeneous LTE/LTE-A or NR network in which different types of eNBs provide coverage for various geographical regions. For example, each eNB, next generation NodeB (gNB), or base station may provide communication coverage for a macro cell, a small cell, or other types of cell. The term "cell" may be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on context.

Base stations may include or may be referred to by those skilled in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, eNodeB (eNB), gNB, Home NodeB, a Home eNodeB, or some other suitable terminology. The geographic coverage area for a base station may be divided into sectors making up only a portion of the coverage area. The wireless communications system or systems described herein may include base stations of different types (e.g., macro or small cell base stations). The UEs described herein may be able to communicate with various types of base stations and network equipment including macro eNBs, small cell eNBs, gNBs, relay base stations, and the like. There may be overlapping geographic coverage areas for different technologies.

The wireless communication system or systems described herein may support synchronous or asynchronous operation.

Each communication link described herein-including, for example, wireless communication system <NUM> of <FIG>-may include one or more carriers, where each carrier may be a signal made up of multiple sub-carriers (e.g., waveform signals of different frequencies).

By way of example, and not limitation, non-transitory computer-readable media may comprise RAM, ROM, electrically erasable programmable read only memory (EEPROM), compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Combinations of the above are also included within the sscope of computer-readable media.

Claim 1:
A method (<NUM>) for wireless communication, comprising:
identifying (<NUM>) a channel raster associated with a plurality of resource blocks of a channel, the plurality of resource blocks having an asymmetric relation with respect to the channel raster, wherein the asymmetric relation indicates that the channel raster is offset from the middle of the channel; and
transmitting (<NUM>, <NUM>), based at least in part on the asymmetric relation, a message to indicate the channel raster and a resource block offset metric that comprises location information associated with a first resource block of the plurality of resource blocks of the channel.