Patent Description:
Examples of such multiple-access systems include fourth generation (<NUM>) systems such as Long-Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (<NUM>) systems which may be referred to as NR systems.

A wireless multiple-access communications system may include a number of base stations or network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UEs). In some wireless communications systems, a base station may transmit control information to a UE in a physical downlink control channel (PDCCH), and the UE may be configured to monitor multiple PDCCH candidates for the PDCCH that includes the control information from the base station. In particular, the UE may perform blind decoding on each of the multiple PDCCH candidates to identify the PDCCH with the control information from the base station. Improved techniques for supporting blind decoding may be desirable. <NPL>) discusses potential fields with size reduction, the potential configurable fields, and PDCCH monitoring capability. <NPL>) provides a detailed discussion about an increased PDCCH monitoring capability.

The described techniques relate to improved methods, apparatuses and computer programs that support relaxed control channel element (CCE) and blind decoding overbooking and dropping for New Radio (NR) ultra-reliable low-latency communications (URLLC). Generally, the described techniques provide for efficiently limiting a number of blind decoding attempts or CCEs that a user equipment (UE) is configured to monitor to limit complexity at the UE. When a UE is configured to use blind decoding for monitoring CCEs in multiple spans in a slot for control information from a base station, the UE may be configured to perform dropping of blind decoding candidates or CCEs in a subset of the spans (e.g., instead of in all of the spans). In other words, the UE may identify a dropping rule to drop CCE monitoring occasions or blind decoding attempts in excess of a maximum number of non-overlapping CCEs per span or a maximum number of blind decoding attempts per span, respectively, and the UE may apply the dropping rule to fewer than all of the spans within the slot. In an embodiment corresponding to the claimed invention, the UE applies the dropping rule to a fixed span within the slot.

In some wireless communications systems, a base station may transmit control information to a user equipment (UE) in a physical downlink control channel (PDCCH), and the UE may be configured to monitor multiple PDCCH candidates or control channel elements (CCEs) for the PDCCH that includes the control information from the base station. In particular, the UE may perform blind decoding on each of the multiple PDCCH candidates or CCEs to identify the PDCCH with the control information from the base station. In some cases, to limit complexity, the UE may be configured to drop blind decoding candidates in a slot in excess of a maximum number of blind decoding attempts and drop CCEs in a slot in excess of a maximum number of non-overlapping CCEs. In some cases, however, if the UE is configured to monitor PDCCH candidates in multiple spans within a slot for control information from a base station, the limit on the number of blind decoding candidates and CCEs may be per span instead of per slot. Thus, the UE may be configured to perform blind decoding candidate or CCE counting and dropping multiple times per slot (e.g., in each span in the slot) instead of once per slot (e.g., since there may be multiple spans per slot). As a result, the process of performing dropping may increase complexity at the UE.

As described herein, a wireless communications system may support efficient techniques for limiting a number of blind decoding attempts or CCEs that a UE is configured to monitor to limit complexity at the UE. In particular, when the UE is configured to use blind decoding for monitoring CCEs in multiple spans in a slot for control information from a base station, the UE may be configured to perform dropping of blind decoding candidates or CCEs in a subset of the spans. That is, the UE may identify a dropping rule to drop CCE monitoring occasions or blind decoding attempts in excess of a maximum number of non-overlapping CCEs per span or a maximum number of blind decoding attempts per span, respectively, and the UE may apply the dropping rule to fewer than all of the spans within the slot. For example, the UE may apply the dropping rule to a first span within the slot and refrain from applying the dropping rule, or not expect to apply the dropping rule, to spans outside of the first span within the slot. In some cases, the UE may transmit an indication of a maximum number of spans in which the UE may perform dropping of blind decoding candidates and CCEs, and the base station may configure common search spaces (CSSs) within spans of a slot such that a number of spans within the slot that include a CSS is less than or equal to the maximum number of spans per slot indicated by the UE.

The described techniques may be implemented to realize one or more advantages. In some implementations, for example, the described techniques may define time-domain resources over which a UE may expect to apply a dropping rule for PDCCH monitoring and time-domain resources over which a UE may not expect to apply a dropping rule for PDCCH monitoring. As such, the UE may limit the complexity associated with PDCCH overbooking and dropping, which may enable one or more processing components of the UE related to PDCCH monitoring to enter a sleep mode more frequently or for longer time durations. Further, the described techniques support the application of dropping rules for PDCCH overbooking within time-domain resources at a sub-slot granularity (e.g., per span instead of per slot), which may support low latency downlink communication.

Aspects of the disclosure introduced above are described herein in the context of a wireless communications system. Examples of processes and signaling exchanges that support relaxed CCE and blind decoding overbooking and dropping for New Radio (NR) ultra-reliable low-latency communications (URLLC) are then described. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to relaxed CCE and blind decoding overbooking and dropping for NR URLLC.

<FIG> illustrates an example of a wireless communications system <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The wireless communications system <NUM> includes base stations <NUM>, UEs <NUM>, and a core network <NUM>. In some examples, the wireless communications system <NUM> may be a Long-Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a NR network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, URLLC, or communications with low-cost and low-complexity devices.

Communication links <NUM> shown in wireless communications system <NUM> may include uplink transmissions from a UE <NUM> to a base station <NUM> (e.g., in a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH)), or downlink transmissions from a base station <NUM> to a UE <NUM> (e.g., in a physical downlink control channel (PDCCH) or a physical downlink shared channel (PDSCH)).

The term "cell" may refer to a logical communication entity used for communication with a base station <NUM> (e.g., over a carrier), and may be associated with an identifier for distinguishing neighboring cells (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID)) operating via the same or a different carrier.

The term "carrier" may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting communications over a communication link <NUM>. A carrier may be associated with a pre-defined frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)) and may be positioned according to a channel raster for discovery by UEs <NUM>. In some examples, signal waveforms transmitted over a carrier may be made up of multiple sub-carriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)).

For example, wireless communications system <NUM> may employ License Assisted Access (LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band such as the <NUM> industrial, scientific, and medical (ISM) band.

In some cases, wireless communications system <NUM> may be a packet-based network that operates according to a layered protocol stack.

A subframe may be further divided into <NUM> slots each having a duration of <NUM>, and each slot may contain <NUM>, <NUM>, or <NUM> orthogonal frequency division multiplexing (OFDM) symbols (e.g., depending on the length of the cyclic prefix prepended to each symbol period).

In some cases, a subframe may be the smallest scheduling unit of the wireless communications system <NUM> and may be referred to as a transmission time interval (TTI).

In the wireless communications system <NUM>, a base station <NUM> may transmit control information to a UE <NUM> over a PDCCH. The UE <NUM> may monitor one or more PDCCH candidates in a search space for the PDCCH including the control information from the base station <NUM>, where each PDCCH candidate may be a possible location for the PDCCH including the control information from the base station <NUM>. In other words, the UE <NUM> may blind decode different PDCCH candidates to identify the control information that was transmitted by the base station <NUM>. The search space may include multiple CCEs, each of which may be a group of resources which can be used to send the PDCCH. CCEs may also be grouped for larger control transmissions. In some cases, it may be appropriate to provide limitations on the number of blind decoding or PDCCH candidates in a search space per slot and a limitation on the number of non-overlapping CCEs per slot. Such limitations may limit complexity at a UE <NUM> since the UE <NUM> may be configured to monitor fewer PDCCH candidates and resources for control information from a base station <NUM>. Tables <NUM> and <NUM> provide examples of limitations on blind decoding and non-overlapping CCEs per slot. Table <NUM>: Maximum number ( <MAT>) of monitored PDCCH candidates per slot for a downlink bandwidth part with subcarrier spacing configuration µ ∈ {<NUM>,<NUM>,<NUM>,<NUM>} for a single serving cell.

Table <NUM>: Maximum number ( <MAT>) of non-overlapped CCEs per slot for a downlink bandwidth part with subcarrier spacing configuration µ ∈ {<NUM>,<NUM>,<NUM>,<NUM>} for a single serving cell.

For each scheduled cell, a UE <NUM> may be configured to monitor no more than the maximum number ( <MAT>) of PDCCH candidates per slot for a subcarrier spacing (SCS) configuration µ as indicated in Table <NUM> or no more than a maximum number ( <MAT>) of PDCCH candidates per slot for an SCS configuration µ under carrier aggregation. In particular, the UE <NUM> may not be configured to monitor more than <MAT> PDCCH candidates per slot on the active downlink bandwidth part with SCS configuration µ. Similarly, for each scheduled cell, the UE <NUM> may be configured to monitor no more than the maximum number ( <MAT>) of non-overlapped CCEs per slot for an SCS configuration µ as indicated in Table <NUM> or no more than a maximum number ( <MAT>) of PDCCH candidates per slot for an SCS configuration µ under carrier aggregation. In particular, the UE <NUM> may not be configured to monitor more than <MAT> non-overlapped CCEs per slot on the active downlink bandwidth part with SCS configuration µ.

In some cases, however, because different search space sets (which may be associated with the same or different control resource sets (CORESETs)) may have different periodicities, there may be a scenario in which the number of blind decoding candidates and the number of CCEs associated with the blind decoding candidates in a slot are more than the maximum values provided in Tables <NUM> and <NUM>, respectively. Such a scenario may be referred to as overbooking and may be allowed on a primary cell (PCell) or primary-secondary cell (PSCell) and not on secondary cells (SCells). In other words, on SCells, the limitations described with reference to Tables <NUM> and <NUM> may be satisfied (e.g., always). To handle overbooking, a UE <NUM> may support techniques for dropping blind decoding candidates and CCEs to limit complexity. Dropping may be specified for user-specific search spaces (USSs), and no dropping may be specified for CSSs. That is, the blind decoding candidates and CCEs for the CSS sets may be protected (e.g., always).

For all search space sets within a slot n, a set of CSS sets with a cardinality of Icss may be denoted by Scss, and a set of USS sets with a cardinality of Juss may be denoted by Suss. The location of USS sets sj, <NUM> ≤ j ≤ Juss in Suss may be according to an ascending order of the search space set index. The number of counted PDCCH candidates for monitoring for a CSS set Scss(i) may be denoted by <MAT>, and the number of counted PDCCH candidates for monitoring for a USS set Suss(j) may be denoted by <MAT>. For the CSS sets, a UE <NUM> may monitor <MAT> PDCCH candidates requiring a total of <MAT> non-overlapping CCEs in a slot. That is, for the CSS sets, the UE <NUM> may monitor all PDCCH candidates, and the UE <NUM> may avoid dropping any blind decoding candidates or CCEs. For the USS sets, however, a UE <NUM> may monitor a subset of PDCCH candidates and a subset of CCEs. That is, the UE <NUM> may drop blind decoding candidates and CCEs in excess of the maximum values described with reference to Tables <NUM> and <NUM>.

In one example, for a Pcell having an active downlink bandwidth part with an SCS configuration µ in slot n, a UE <NUM> may allocate PDCCH candidates according to a dropping rule, and the UE <NUM> may not expect to monitor PDCCH in a USS set without allocated PDCCH candidates for monitoring. The set of non-overlapping CCEs for search space Suss(j) may be denoted by VCCE(Suss(j)), and the cardinality of VCCE(Suss(j)) may be denoted by cardinality(VCCE(Suss(j))). The non-overlapping CCEs for search space set Suss(j) may be determined considering the allocated PDCCH candidates for monitoring for the CSS sets and the allocated PDCCH candidates for monitoring for all search space sets Suss(k), <NUM> ≤ k ≤ j. The dropping rule may correspond to the following pseudocode:
<IMG>.

In some wireless communications systems (e.g., wireless communications systems supporting URLLC), an updated PDCCH monitoring capability may be supported. For instance, similar to a PDCCH monitoring capability <NUM>-5b, a UE <NUM> may be configured to monitor multiple spans per slot, where a span may correspond to a subset of the OFDM symbols within a slot. PDCCH monitoring occasions associated with some features (e.g., in a feature group (FG) <NUM>-<NUM>), plus additional PDCCH monitoring occasions may be in any OFDM symbols of a slot (e.g., for a case <NUM>). For any two PDCCH monitoring occasions belonging to different spans, provided that at least one PDCCH monitoring occasion is not one of the PDCCH monitoring occasions associated with FG-<NUM>-<NUM>, in same or different search spaces, there may be a minimum time separation of X OFDM symbols (including the cross-slot boundary case) between the start of two spans, where each span is of length up to Y consecutive OFDM symbols of a slot. Each span may include multiple search spaces, and there may be two spans in a slot if (X, Y) = (<NUM>,<NUM>), three spans in a slot if (X, Y) = (<NUM>,<NUM>), and seven spans in a slot if (X, Y) = (<NUM>,<NUM>).

Spans may not overlap, and every span may be contained in a single slot. The same span pattern may repeat in every slot. The separation between consecutive spans within and across slots may be unequal, but the same (X,Y) limit may be satisfied by all spans. Every monitoring occasion may be fully contained in one span. In order to determine a suitable span pattern, first a bitmap b(l), <NUM> ≤ l ≤ <NUM> may be generated, where b(l) = <NUM> if symbol l of any slot is a part of a monitoring occasion, and b(l) = <NUM> otherwise. The first span in the span pattern may begin at the smallest l for which b(l) = <NUM>. The next span in the span pattern may begin at the smallest l not included in the previous spans for which b(l) = <NUM>. The span duration may be the higher value of the maximum value of all CORESET durations and the minimum value of Y in the UE reported candidate value, except possibly the last span in a slot which can be of shorter duration. A PDCCH monitoring configuration may meet the UE capability limitation if the span arrangement satisfies the gap separation for at least one (X,Y) in the UE reported candidate value set in every slot, including cross slot boundary.

In some cases, a UE <NUM> may process control information using various techniques for the set of monitoring occasions that are within the same span. In one example, the UE <NUM> may process one unicast downlink control information (DCI) scheduling downlink communications and one unicast DCI scheduling uplink communications per scheduled component carrier across the set of monitoring occasions for FDD. In another example, the UE <NUM> may process one unicast DCI scheduling downlink communications and two unicast DCI scheduling uplink communications per scheduled component carrier across the set of monitoring occasions for TDD. In yet another example, the UE <NUM> may process two unicast DCI scheduling downlink communications and one unicast DCI scheduling uplink communications per scheduled component carrier across the set of monitoring occasions for TDD. The number of different start symbol indices of spans for all PDCCH monitoring occasions per slot, including PDCCH monitoring occasions of FG-<NUM>-<NUM>, may be no more than floor(<NUM>/X), where X is the minimum among values reported by a UE <NUM>. The number of different start symbol indices of PDCCH monitoring occasions per slot including PDCCH monitoring occasions of FG-<NUM>-<NUM>, may be no more than seven. The number of different start symbol indices of PDCCH monitoring occasions per half-slot including PDCCH monitoring occasions of FG-<NUM>-<NUM> may be no more than four in an SCell.

As described above, the techniques for dropping blind decoding candidates and CCEs may be supported to limit decoding complexity at a UE <NUM>. However, in systems in which a UE <NUM> is configured to monitor PDCCH candidates in multiple spans in a slot for control information from a base station <NUM>, the limit on the number of blind decoding candidates and CCEs may be per span (e.g., instead of per slot). Accordingly, the UE <NUM> may perform CCE or blind decoding candidate counting and dropping multiple times per slot instead of once per slot (e.g., because there may be multiple spans per slot), which may result in increased complexity at the UE <NUM>. UEs <NUM> in the wireless communications system <NUM> may support efficient techniques for monitoring for control information from a base station <NUM> with limited complexity.

<FIG> illustrates an example of a wireless communications system <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The wireless communications system <NUM> includes a UE <NUM>-a, which may be an example of a UE <NUM> as described with reference to <FIG>. The wireless communications system <NUM> also includes a base station <NUM>-a, which may be an example of a base station <NUM> as described with reference to <FIG>. The base station <NUM>-a may provide communication coverage for a coverage area <NUM>-a. For example, the base station <NUM>-a may communicate with the UE <NUM>-a with the coverage area <NUM>-a over resources of a carrier <NUM>. The wireless communications system <NUM> may implement aspects of the wireless communications system <NUM>. For example, the UE <NUM>-a in the wireless communications system <NUM> may support efficient techniques for monitoring for control information from the base station <NUM>-a with limited complexity.

For example, if the UE <NUM>-a is configured to monitor PDCCH candidates for control information from the base station <NUM>-a in multiple spans <NUM> (including a span <NUM>-a, a span <NUM>-b, and a span <NUM>-c) in a slot <NUM>, the UE <NUM>-a may be expected to perform blind decoding candidate or CCE dropping in a subset of the spans <NUM> in the slot <NUM> (e.g., on a PCell or a PSCell) due to overbooking in the slot <NUM>. In other words, the UE <NUM>-a may identify a dropping rule for the UE <NUM>-a to drop CCE monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping CCE per span or the maximum number of blind decoding attempts per span, respectively, and the UE <NUM>-a may apply the dropping rule to fewer than all of the spans <NUM> in the slot <NUM>. In some cases, the UE <NUM>-a may perform dropping in the spans <NUM> in which CSS is present (e.g., it may be unnecessary to perform dropping in other spans).

In some cases, the UE <NUM>-a may perform dropping in a fixed set of spans (of the multiple spans <NUM>) in the slot <NUM>. For example, the fixed set of spans may include a single span (of the multiple spans <NUM>) in the slot <NUM>, a consecutive number of spans (of the multiple spans <NUM>) from the beginning of the slot <NUM>, or a consecutive number of spans (of the multiple spans <NUM>) from the end of the slot <NUM>. The fixed set of spans may also include temporally-spaced spans (of the multiple spans <NUM>) within the slot <NUM> (e.g., every other span). In some cases, the UE <NUM>-a may also perform dropping in the fixed set of spans (of the multiple spans <NUM>) in the slot <NUM> where the fixed set of spans includes a first span in time (of the multiple spans <NUM>) in the slot <NUM>, or where the fixed set of spans is a single span including the first span in time (of the multiple spans <NUM>) in the slot <NUM>. In some cases, the UE <NUM>-a may also perform dropping in the fixed set of spans (of the multiple spans <NUM>) in the slot <NUM> where the fixed set of spans includes at least one span in which a CSS is present. For example, the CSS may be present and limited to a first span in time (of the multiple spans <NUM>) in the slot <NUM>. In some other cases, the UE <NUM>-a may avoid performing dropping in any slot where CSS is not present (e.g., since CSS may not be present in all slots due to the periodicity of CSS sets).

<FIG> illustrates an example of a process flow <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The process flow <NUM> illustrates aspects of techniques performed by a UE <NUM>-b, which may be an example of a UE <NUM> as described with reference to <FIG> and <FIG>. The process flow <NUM> also illustrates aspects of techniques performed by a base station <NUM>-b, which may be an example of a base station <NUM> as described with reference to <FIG> and <FIG>. The UE <NUM>-b in the process flow <NUM> may support efficient techniques for monitoring for control information from the base station <NUM>-b with limited complexity. For example, the UE <NUM>-b may be configured with a maximum number of spans (e.g., as a UE capability or as a pre-configuration) in which the UE <NUM>-b may perform dropping of blind decoding candidates and CCEs to limit complexity.

At <NUM>, the UE <NUM>-b may determine, as a UE capability or as a pre-configuration, a maximum number of spans in which the UE <NUM>-b is able to apply a dropping rule. Thus, based on the maximum number of spans, the UE <NUM>-b may apply the dropping rule to fewer than all of the spans within a slot in which the UE <NUM>-b is configured to monitor PDCCH candidates for control information from the base station <NUM>-b. In examples in which the UE <NUM>-b determines the maximum number of spans based on the UE capability, at <NUM>, the UE <NUM>-b may transmit the UE capability indicating the maximum number of spans to the base station <NUM>-b. In examples in which the UE <NUM>-b determines the maximum number of spans based on the pre-configuration, the UE <NUM>-b may refrain from transmitting the UE capability to the base station <NUM>-b at <NUM>. In some cases, the maximum number of spans in which the UE <NUM>-b is to apply the dropping rule may be the same for all values of X corresponding to the minimum time separation between spans (e.g., span timing) and all values of Y corresponding to span length (e.g., length configurations). Alternatively, the maximum number of spans in which the UE <NUM>-b is to apply the dropping rule may be different for different values of X and Y.

In yet other cases, the maximum number of spans in which the UE <NUM>-b is to apply the dropping rule may be different based on whether a PCell is configured with a first or second PDSCH or PUSCH minimum processing time capability (e.g., a minimum processing time capability number one or number two). In such cases, the UE <NUM>-b may determine the maximum number of spans in which the UE <NUM>-b is able to apply the dropping rule based on the PDSCH or PUSCH minimum processing time capability of a cell with which the UE communicates over the slot.

Additionally or alternatively, at <NUM>, the UE <NUM>-b may determine, as a UE capability or a pre-configuration, a fixed span (or a fixed set of spans) in which the UE <NUM>-b is able to apply a dropping rule. Thus, based on the fixed span, the UE <NUM>-b may apply the dropping rule to fewer than all of the spans within a slot in which the UE <NUM>-b is configured to monitor PDCCH candidates for control information from the base station <NUM>-b. In examples in which the UE <NUM>-b determines the fixed span based on the UE capability, at <NUM>, UE <NUM>-b may transmit the UE capability indicating the fixed set of spans to the base station <NUM>-b. In examples in which the UE <NUM>-b determines the fixed span based on the pre-configuration, the UE <NUM>-b may refrain from transmitting the UE capability to the base station <NUM>-b at <NUM>. In examples in which the UE <NUM>-b identifies or otherwise determines a fixed set of spans, the fixed set of spans may include a first temporal span (e.g., a first span in time) within the slot. In examples in which the UE <NUM>-b identifies or otherwise determines a fixed span, the fixed span may be a single span and include the first temporal span (e.g., the first span in time) within the slot.

In some implementations, such as in implementations in which the UE <NUM>-b transmits the UE capability at <NUM>, the base station <NUM>-b may receive the UE capability message from the UE <NUM>-b indicating the maximum number of spans or the fixed span in which the UE <NUM>-b is to apply the dropping rule. At <NUM>, the base station <NUM>-b may configure one or more CSS within spans of a slot for communications with the UE <NUM>-b such that a number of spans within the slot that include a CSS is less than or equal to the maximum number of spans per slot indicated by the UE capability. That is, the base station <NUM>-b may ensure that CSS sets fail to exist in more spans than the maximum number of spans in any slot of a PCell or PSCell indicated by the UE <NUM>-b.

Additionally or alternatively, at <NUM>, the base station <NUM>-b may configure one or more CSSs within spans of a slot for communications with the UE <NUM>-b such that at least one span of the fixed set of spans within the slot indicated by the UE capability includes a CSS. That is, the base station <NUM>-b may ensure that CSS sets exist (e.g., only exist) in the fixed set of spans in any slot of a PCell or PSCell. In some cases, the at least one span of the fixed set of spans may be a first span in time within the slot. In some cases, the CSS may be the only CSS configured within the spans of the slot for communication with the UE <NUM>-b. In some cases, base station <NUM>-b may configure a limited number of CSSs. The limited number of CSSs may be included with at least one (but in some cases all) of the fixed set of spans within the slot. For example, base station <NUM>-b may configure a single CSS to be included with a first span in time within the slot. In some cases, configuring the single CSS to be included with the first span in time within the slot may be performed irrespective of the UE capability, as the base station <NUM>-b may assume that the UE <NUM>-b is capable of dropping the first span in time within the slot that includes the only CSS in the slot. Additionally or alternatively, the base station <NUM>-b may identify the fixed span (or the fixed set of spans) in which the UE <NUM>-b is to apply the dropping rule without signaling from the UE <NUM>-b (e.g., based on a pre-configuration), and may configure one or more CSSs within spans of the slot including at least the fixed span.

At <NUM>, the base station <NUM>-b may then indicate, to the UE <NUM>-b, a CSS configuration in accordance with the configuring at <NUM>. For example, the CSS configuration may indicate that a number of spans within a slot that include a CSS is less than or equal to the maximum number of spans per slot indicated by the UE capability, or the CSS configuration may indicate that at least one span of the fixed set of spans within the slot indicated by the UE capability includes a CSS.

At <NUM>, the UE <NUM>-b may apply the dropping rule to the maximum number of spans or to the fixed span. In some examples, the fixed span may include the first temporal span of the slot and the UE <NUM>-b may accordingly apply the dropping rule to the first temporal span of the slot.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The 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).

The 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 relaxed CCE and blind decoding overbooking and dropping for NR URLLC, etc.). Information may be passed on to other components of the device <NUM>. 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.

The communications manager <NUM> may determine that the UE is configured to use blind decoding for monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of blind decoding attempts per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot, identify a dropping rule for the UE to drop control channel element monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of blind decoding attempts per span, respectively, and apply the dropping rule to fewer than all spans within the slot. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

In some examples, the communications manager <NUM> may be implemented as an integrated circuit or chipset for a mobile device modem, and the receiver <NUM> and the transmitter <NUM> may be implemented as analog components (for example, amplifiers, filters, antennas) coupled to the mobile device modem to enable wireless transmission and reception over one or more bands.

The communications manager <NUM> may be implemented to realize one or more potential advantages. In some implementations, the communications manager <NUM> may identify a fixed span in which the communications manager <NUM> may apply a dropping rule to address PDCCH overbooking within the fixed span (e.g., PDCCH overbooking may be constrained to be within the fixed span). As such, the communications manager <NUM>, or one or more processing components of the communications manager <NUM> associated with the application of a dropping rule, may apply the dropping rule within the fixed span and refrain from applying the dropping rule outside of the fixed span, which may enable the communications manager <NUM>, or the one or more processing components of the communications manager <NUM> associated with the application of the dropping rule, to enter a sleep mode more frequently or for longer durations. As such, the communications manager <NUM> may consume less power, which may improve power savings and increase battery life at the device <NUM>.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The 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).

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include a blind decoder <NUM> and a dropping manager <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The blind decoder <NUM> may determine that the UE is configured to use blind decoding for monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of blind decoding attempts per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot. The dropping manager <NUM> may identify a dropping rule for the UE to drop control channel element monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of blind decoding attempts per span, respectively and apply the dropping rule to fewer than all spans within the slot.

<FIG> shows a block diagram <NUM> of a communications manager <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include a blind decoder <NUM>, a dropping manager <NUM>, a UE capability manager <NUM>, and a CSS manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The blind decoder <NUM> may determine that the UE is configured to use blind decoding for monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of blind decoding attempts per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot. The dropping manager <NUM> may identify a dropping rule for the UE to drop control channel element monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of blind decoding attempts per span, respectively. In some examples, the dropping manager <NUM> may apply the dropping rule to fewer than all of the spans within the slot.

In some examples, the dropping manager <NUM> may drop one or more control channel element monitoring occasions or one or more blind decoding attempts for only a number of spans in which a common search space is present. In some examples, the dropping manager <NUM> may drop one or more control channel element monitoring occasions or one or more blind decoding attempts for a number of spans in which a common search space is present and when the slot is for communications with either a PCell or a PSCell. In some examples, the dropping manager <NUM> may refrain from applying the dropping rule in a number of spans that do not include a common search space. In some examples, the dropping manager <NUM> may refrain from applying the dropping rule to any span within the slot based on the slot not including a common search space.

The UE capability manager <NUM> may determine a maximum number of spans in which the UE may apply the dropping rule, where applying the dropping rule to fewer than all of the spans within the slot is based on the maximum number of spans determined by the UE. In some examples, the maximum number of spans may be based on a UE capability and, in such examples, the UE capability manager <NUM> may transmit the UE capability to a base station. The CSS manager <NUM> may identify that a number of spans that include a common search space within the slot is in accordance with the UE capability. In some cases, the determined maximum number of spans is common for different span timing and length configurations for the UE. In some cases, the determined maximum number of spans is different for different span timing and length configurations for the UE.

In some examples, the UE capability manager <NUM> may determine the maximum number of spans in which the UE may apply the dropping rule based on a PDSCH or PUSCH minimum processing time capability of a cell with which the UE communicates over the slot. In some examples, the UE capability manager <NUM> may determine a fixed set of spans within the slot in which the UE may apply the dropping rule. In such examples, the dropping manager <NUM> may drop one or more control channel element monitoring occasions or one or more blind decoding attempts for only a number of spans in which a common search space is present, such that applying the dropping rule to fewer than all of the spans within the slot may include dropping one or more control channel element monitoring occasions or one or more blind decoding attempts for the fixed set of spans. In some cases, the fixed set of spans includes a first temporal span within the slot. In some cases, the fixed set of spans includes at least one span in which a CSS is present.

In some examples, the UE capability manager <NUM> may determine a fixed span within the slot in which the UE may apply the dropping rule. In such examples, the dropping manager <NUM> may drop one or more control channel element monitoring occasions or one or more blind decoding attempts for the fixed span, such that applying the dropping rule to fewer than all of the spans within the slot may include dropping one or more control channel element monitoring occasions or one or more blind decoding attempts for the fixed span. In some cases, the fixed span may include a first temporal span within the slot. In some cases, the fixed span includes a span in which a CSS is present.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, an I/O controller <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, and a processor <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communications manager <NUM> may determine that the UE is configured to use blind decoding for monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of blind decoding attempts per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot, identify a dropping rule for the UE to drop control channel element monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of blind decoding attempts per span, respectively, and apply the dropping rule to fewer than all spans within the slot.

In some cases, the memory <NUM> may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The 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, the processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting relaxed CCE and blind decoding overbooking and dropping for NR URLLC).

<FIG> shows a block diagram <NUM> of a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The 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).

In some examples, the communications manager <NUM> may identify a maximum number of spans per slot in which the UE may apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule, configure one or more common search spaces within spans of a slot for communication with the UE such that a number of spans within the slot that include a common search space is less than or equal to the maximum number of spans per slot, and indicate, to the UE, a common search space configuration in accordance with the configuring.

Additionally or alternatively, the communications manager <NUM> may identify a fixed span within a slot in which a UE may apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule, configure one or more common search spaces within spans of the slot for communication with the UE such that at least the fixed span within the slot includes a common search space, and indicate, to the UE, a common search space configuration in accordance with the configuring. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

If implemented in code executed by a processor, the functions of the communications manager <NUM>, or its 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.

In some examples, the communications manager <NUM>, or its 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.

The communications manager <NUM> may be implemented to realize one or more potential advantages. In some implementations, the communications manager <NUM> may configure CSSs based on a fixed span (e.g., a first temporal span) within a slot over which the UE <NUM>-a may apply a dropping rule for PDCCH overbooking. The CSS configuration based on such a defined fixed span for PDCCH overbooking may enable the communications manager <NUM> to support the scheduling and transmitting of control information to one or more UEs with lower latency, which may result in greater system capacity and increased throughput, among other benefits.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The 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).

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include a UE capability manager <NUM>, a CSS manager <NUM>, and a UE configuration manager <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The UE capability manager <NUM> may identify a maximum number of spans per slot in which the UE may apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule. The CSS manager <NUM> may configure one or more common search spaces within spans of a slot for communication with the UE such that a number of spans within the slot that include a common search space is less than or equal to the maximum number of spans per slot. The UE configuration manager <NUM> may indicate, to the UE, a common search space configuration in accordance with the configuring.

Additionally or alternatively, the UE capability manager <NUM> may identify a fixed span within a slot in which a UE may apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule. The CSS manager <NUM> may configure one or more common search spaces within spans of the slot for communication with the UE such that at least the fixed span within the slot includes a common search space. The UE configuration manager <NUM> may indicate, to the UE, a common search space configuration in accordance with the configuring.

<FIG> shows a block diagram <NUM> of a communications manager <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include a UE capability manager <NUM>, a CSS manager <NUM>, and a UE configuration manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

In some cases, the maximum number of spans is common for different span timing and length configurations for the UE. In some cases, the maximum number of spans is different for different span timing and length configurations for the UE. In some cases, the maximum number of spans is based on a PDSCH or PUSCH minimum processing time capability of a cell associated with the base station and with which the UE communicates over the slot. In some cases, the at least one span of the fixed set of spans is a first span in time within the slot. In some cases, the common search space is the only common search space configured within the spans of the slot for communication with the UE.

In some examples, the UE capability manager <NUM> may identify a fixed span within a slot in which a UE is to apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule. In some examples, the CSS manager <NUM> may configure one or more common search spaces within spans of the slot for communication with the UE such that at least the fixed span within the slot includes a common search space. In some examples, the UE configuration manager <NUM> may indicate, to the UE, a common search space configuration in accordance with the configuring. In some cases, the fixed span is a first temporal span within the slot. In some cases, the common search space is an only common search space configured within the spans of the slot for communication with the UE.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, a network communications manager <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, a processor <NUM>, and an inter-station communications manager <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

Additionally or alternatively, the communications manager <NUM> may may identify a fixed span within a slot in which a UE may apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule, configure one or more common search spaces within spans of the slot for communication with the UE such that at least the fixed span within the slot includes a common search space, and indicate, to the UE, a common search space configuration in accordance with the configuring.

The 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, the processor <NUM> may be configured to operate a memory array using a memory controller. In some cases, a memory controller may be integrated into processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting relaxed CCE and blind decoding overbooking and dropping for NR URLLC).

The 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>.

<FIG> shows a flowchart illustrating a method <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC 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 communications manager as described with reference to <FIG>. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described herein. Additionally, or alternatively, a UE may perform aspects of the functions described herein using special-purpose hardware.

At <NUM>, the UE may determine that the UE is configured to use blind decoding for monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of blind decoding attempts per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a blind decoder as described with reference to <FIG>.

At <NUM>, the UE may identify a dropping rule for the UE to drop control channel element monitoring occasions or blind decoding attempts in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of blind decoding attempts per span, respectively. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a dropping manager as described with reference to <FIG>.

At <NUM>, the UE may apply the dropping rule to fewer than all spans within the slot. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a dropping manager as described with reference to <FIG>.

<FIG> shows a flowchart illustrating a method <NUM> that supports relaxed CCE and blind decoding overbooking and dropping for NR URLLC 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 communications manager as described with reference to <FIG>. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the functions described herein. Additionally, or alternatively, a base station may perform aspects of the functions described herein using special-purpose hardware.

At <NUM>, the base station may identify a maximum number of spans per slot in which a UE is to apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule. Additionally or alternatively, at <NUM>, the base station may identify a fixed span within a slot in which the UE is to apply a dropping rule, where the dropping rule indicates that the UE is to drop control channel element monitoring occasions or blind decoding attempts in accordance with the dropping rule. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a UE capability manager as described with reference to <FIG>.

At <NUM>, the base station may configure one or more common search spaces within spans of a slot for communication with the UE such that a number of spans within the slot that include a common search space is less than or equal to the maximum number of spans per slot. Additionally or alternatively, at <NUM>, the base station may configure one or more common search spaces within spans of the slot for communication with the UE such that at least the fixed span within the slot includes a common search space. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a CSS manager as described with reference to <FIG>.

At <NUM>, the base station may indicate, to the UE, a common search space configuration in accordance with the configuring. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a UE configuration manager as described with reference to <FIG>.

By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, 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.

Claim 1:
A method for wireless communications at a user equipment, UE (<NUM>-b), comprising:
monitoring control channel elements in a control resource set in accordance with at least one of a maximum number of physical downlink control channel, PDCCH, candidates per span within a slot or a maximum number of non-overlapping control channel elements per span within the slot;
identifying a dropping rule for the UE to drop control channel element monitoring occasions or PDCCH candidates in excess of the maximum number of non-overlapping control channel elements per span or the maximum number of PDCCH candidates per span, respectively; and
applying the dropping rule to fewer than all spans within the slot,
wherein the method further comprises:
determining (<NUM>) a fixed span within the slot in which the UE is to apply the dropping rule, wherein applying the dropping rule to fewer than all of the spans within the slot comprises:
dropping one or more control channel element monitoring occasions or one or more PDCCH candidates for the fixed span.