Blind detection and control channel element monitoring restrictions in carrier aggregation

Abstract

A system and method for setting blind detection and control channel element monitoring limits in a carrier aggregation scheme. In some embodiments, the method includes receiving, by a network, a capability declaration of a first user equipment (UE) from the first UE, sending, by the network, a first search space (SS) configuration for a first component carrier in a carrier aggregation (CA) scheme to the first UE, and sending, by the network, a second SS configuration for a second component carrier in the CA scheme to the first UE. The first SS configuration can define a first set of monitoring occasions (MOs), the second SS configuration can define a second set of MOs, and an aligned span pattern corresponding to the first set of MOs and the second set of MOs can conform to the capability declaration of the first UE.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims the benefit of (i) U.S. Provisional Application No. 62 / 985,181, filed March 4, 2020, entitled “Systems and Methods for Providing PDCCH Monitoring Limit Design in Carrier Aggregation (CA) and Dual Connectivity (DC) Based on Monitoring Span,” (ii) U.S. Provisional Application No. 63 / 000,049, filed March 26, 2020, entitled “PDCCH BD / CCE Limit Determination for URLLC with Carrier Aggregation Framework,” (iii) U.S. Provisional Application No. 63 / 025,779, filed May 15, 2020, entitled “PDCCH BD / CCE Limit Determination for URLLC with Carrier Aggregation Framework with Span Pattern Definition,” and (iv) U.S. Provisional Application No. 63 / 081,125, filed September 21, 2020, entitled “Method for Determining PDCCH Monitoring Limit Misalignment Span in CA / DC Based on Monitoring Span,” all of which are incorporated by reference herein in their entireties. TECHNICAL FIELD

[0003] One or more aspects of embodiments in accordance with the present disclosure relate to wireless communications, and more particularly, to systems and methods for setting blind detection and control channel element monitoring limits in carrier aggregation schemes. BACKGROUND

[0004] In wireless systems, it can be advantageous to allow a network to schedule physical downlink control channel (PDCCH) candidates in a flexible manner without scheduling them in a way that burdens a user equipment to an unacceptable degree. A simple limit on blind detection and control channel element monitoring can be able to protect a user equipment from being overburdened, but such a limit can not be flexible enough to limit the performance of the network, particularly in carrier aggregation (CA) schemes.

[0005] Accordingly, there is a need for an improved system and method for setting blind detection and control channel element monitoring limits in carrier aggregation schemes. SUMMARY

[0006] According to one embodiment of the disclosure, a method is provided, comprising: receiving, by a network from a first user equipment (UE), a capability declaration of the first UE; sending, by the network to the first UE, a first search space (SS) configuration for a first component carrier in a carrier aggregation (CA) scheme; and sending, by the network to the first UE, a second SS configuration for a second component carrier in the CA scheme, wherein: the first SS configuration defines a first set of monitoring occasions (MOs), the second SS configuration defines a second set of MOs, and an aligned span pattern corresponding to the first set of MOs and the second set of MOs complies with the capability declaration of the first UE.

[0007] In some embodiments, the aligned span pattern is a span pattern corresponding to a union of the first set of MOs and the second set of MOs.

[0008] In some embodiments, a total number of PDCCH candidates in the first set of MOs and the second set of MOs is at most equal to a maximum number of PDCCH candidates, the maximum number of PDCCH candidates being based on: a number of serving cells configured with span-based monitoring capability, a specified constant, and a number of downlink cells with span-based monitoring capability that the UE is configured with.

[0009] In some embodiments, the maximum number of PDCCH candidates is equal to wherein: is a reference number of serving cells with span-based monitoring capability and is included in the capability declaration of the first UE, is a specified constant, and is a number of downlink cells with span-based monitoring capability that the UE is configured with.

[0010] In some embodiments, the first set of MOs and the second set of MOs together comprise a number of control channel elements (CCEs), and the number of CCEs is at most equal to a maximum number of CCEs, the maximum number of CCEs being based on: a number of serving cells configured with span-based monitoring capability, a specified constant, and a number of downlink cells with span-based monitoring capability that the UE is configured with.

[0011] In some embodiments, the maximum number of CCEs is equal to wherein: is a reference number of serving cells with span-based monitoring capability and is included in the capability declaration of the first UE, is a specified constant, and is a number of downlink cells with span-based monitoring capability configured for the UE.

[0012] In some embodiments, the method further includes receiving, by the network from a second user equipment (UE), a capability declaration of the second UE; transmitting, by the network to the second UE, a third search space configuration for the first component carrier; and transmitting, by the network to the second UE, a fourth search space configuration for the second component carrier, wherein: the third search space configuration defines a third set of monitoring occasions (MOs), the fourth search space configuration defines a fourth set of monitoring occasions, and a span pattern corresponding to the third set of monitoring occasions and a span pattern corresponding to the fourth set of monitoring occasions are not aligned.

[0013] In some embodiments, the third search space configuration includes at most PDCCH candidates, wherein is based on the capability declaration of the second UE.

[0014] In some embodiments, the third search space configuration includes at most control channel elements, wherein is based on the capability declaration of the second UE.

[0015] In some embodiments: the capability declaration of the first UE includes: a first span-gap span-length pair and a second span-gap span-length pair; the method further includes: determining a first span pattern of the first span-gap span-length pair and the first set of monitoring occasions, the first span pattern being a span pattern assuming the span-gap span-length pair, which includes the first set of control resource sets and the first set of search spaces; determining that the first span pattern is valid for the first span-gap span-length pair; determining a second span pattern of the second span-gap span-length pair and the first set of monitoring occasions, the second span pattern being a span pattern assuming the span-gap span-length pair, which includes the first set of monitoring occasions; and determining that the second span pattern is valid for the second span-gap span-length pair.

[0016] In some embodiments, the method further includes: determining that the first span-gap span-length pair corresponds to a first specified constant, the first specified constant specifying a maximum number of monitored PDCCH candidates; and determining that the second span-gap span-length pair corresponds to a second specified constant, the first specified constant specifying a maximum number of monitored PDCCH candidates, the second specified constant being greater than the first specified constant.

[0017] In some embodiments, the method further comprises: determining that the first span-gap span-length pair corresponds to a first specified constant, the first specified constant specifying a maximum number of non-overlapping control channel elements; and determining that the second span-gap span-length pair corresponds to a second specified constant, the first specified constant specifying a maximum number of non-overlapping control channel elements, the second specified constant being greater than the first specified constant.

[0018] In some embodiments, the method further comprises: indicating, by the network, to the UE to transition to a bandwidth part that does not support span-based PDCCH monitoring, and sending, by the network to the UE, a third search space configuration, the third search space configuration being a search space configuration for slot-based PDCCH monitoring.

[0019] In some embodiments: the aligned span pattern comprises: a first span pattern of the first search space configuration and a second span pattern of the second search space configuration, and every two spans: have the same starting and ending symbols, or have a time gap between the starts of the two spans that is equal to or greater than a span-gap span-length pair of span gap elements of the capability declaration of the first UE.

[0020] In some embodiments: the aligned span pattern comprises: a first span pattern of the first search space configuration and a second span pattern of the second search space configuration, and every two spans: have the same starting symbol, or have a time gap between the starts of the two spans that is equal to or greater than a span-gap span-length pair of span gap elements of the capability declaration of the first UE.

[0021] In some embodiments: the aligned span pattern comprises: a first span pattern of the first search space configuration and a second span pattern of the second search space configuration, and every two spans: have the same ending symbol, or have a time gap between the starts of the two spans that is equal to or greater than a span-gap span-length pair of span gap elements of the capability declaration of the first UE.

[0022] In some embodiments: the aligned span pattern comprises: a first span pattern of the first search space configuration and a second span pattern of the second search space configuration, and every two spans: have the same starting symbol, or have the same ending symbol, or have a time gap between the starts of the two spans that is equal to or greater than a span-gap span-length pair of span gap elements of the capability declaration of the first UE.

[0023] In some embodiments, the method further comprises: transmitting, by the network, a set of slots comprising: in a first slot of the set of slots, an aligned span pattern corresponding to the first set of monitoring occasions and the second set of monitoring occasions, and one or more unaligned slots, wherein: a longest set of consecutive aligned slots within the set of slots comprises less than P slots, and P is a specified constant greater than 3 and less than 100.

[0024] According to one embodiment of the disclosure, there is provided a system comprising a user equipment (UE), the UE comprising processing circuitry configured to: transmit, to a network, a capability declaration of the UE; receive, from the network, a first search space configuration for a first component carrier in a carrier aggregation (CA) scheme; and receive, from the network, a second search space configuration for a second component carrier in the carrier aggregation scheme, wherein: the first search space configuration defines a first set of monitoring occasions (MOs), the second search space configuration defines a second set of monitoring occasions, and an aligned span pattern corresponding to the first set of monitoring occasions and the second set of monitoring occasions complies with the capability declaration of the UE.

[0025] In some embodiments, the aligned span pattern is a span pattern corresponding to a union of the first set of monitoring occasions and the second set of monitoring occasions.

[0026] In some embodiments, the processing circuitry is further configured to: receive, from the network, a third search space configuration for a third component carrier in the carrier aggregation scheme; and receive, from the network, a fourth search space configuration for a fourth component carrier in the carrier aggregation scheme, wherein: the third search space configuration defines a third set of monitoring occasions (MOs), the fourth search space configuration defines a fourth set of monitoring occasions, and an unaligned span pattern corresponding to the third set of monitoring occasions and the fourth set of monitoring occasions complies with the capability declaration of the UE.

[0027] According to one embodiment of the disclosure, there is provided a system comprising a network, the network comprising processing circuitry configured to: receive, from a user equipment (UE), a capability declaration of the UE; transmit, to the UE, a first search space configuration for a first component carrier in a carrier aggregation (CA) scheme; and transmit, to the UE, a second search space configuration for a second component carrier in the carrier aggregation scheme, wherein: the first search space configuration defines a first set of monitoring occasions (MOs), the second search space configuration defines a second set of monitoring occasions, and an aligned span pattern corresponding to the first set of monitoring occasions and the second set of monitoring occasions complies with the capability declaration of the UE.

[0028] In some embodiments, the aligned span pattern is a span pattern corresponding to a union of the first set of monitoring occasions and the second set of monitoring occasions. BRIEF DESCRIPTION OF DRAWINGS

[0029] These and other features and advantages of the present application will be appreciated, as they can be best understood, in reference to the specification, claims, and accompanying drawings in which:

[0030] Figure 1A Table defining certain aspects of span-based monitoring according to embodiments of the present disclosure;

[0031] Figure 1B Table defining certain aspects of span-based monitoring according to embodiments of the present disclosure;

[0032] Figure 1C Span diagram according to embodiments of the present disclosure;

[0033] Figure 1D Span diagram according to embodiments of the present disclosure;

[0034] Figure 1E Table defining certain aspects of span-based monitoring according to embodiments of the present disclosure;

[0035] Figure 1F Table defining certain aspects of span-based monitoring according to embodiments of the present disclosure;

[0036] Figure 2A Span diagram according to embodiments of the present disclosure;

[0037] Figure 2B Span diagram according to embodiments of the present disclosure;

[0038] Figure 2C Span diagram according to embodiments of the present disclosure;

[0039] Figure 2D Span diagram according to embodiments of the present disclosure;

[0040] Figure 2E Span diagram according to embodiments of the present disclosure;

[0041] Figure 2F Span diagram according to embodiments of the present disclosure;

[0042] Figure 2G Span diagram according to embodiments of the present disclosure;

[0043] Figure 2H Span diagram according to embodiments of the present disclosure;

[0044] Figure 2I-1 and 2I-2 Span diagram according to embodiments of the present disclosure;

[0045] Figure 2J Span diagram according to embodiments of the present disclosure;

[0046] Figure 2K is a span graph according to embodiments of the present disclosure;

[0047] Figure 2L is a span graph according to embodiments of the present disclosure;

[0048] Figure 2M is a span graph according to embodiments of the present disclosure.

[0049] Figure 3A is a flow graph according to embodiments of the present disclosure

[0050] Figure 3B is a flow graph according to embodiments of the present disclosure. DETAILED DESCRIPTION

[0051] The detailed description set forth below, in connection with the appended drawings, is intended as a description of exemplary embodiments of systems and methods provided according to the present disclosure for setting blind detection and control channel element monitoring restrictions in a carrier aggregation scheme and is not intended to represent the only forms in which the present application can be constructed or utilized. The description sets forth the features of the present application in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures can be accomplished by different embodiments that are also intended to fall within the scope of the application. As shown elsewhere herein, like element numbers are intended to indicate like or equivalent elements or features.

[0052] In a cellular system, a user equipment (UE) can monitor a physical downlink control channel (PDCCH) search space (SS) to obtain downlink control information (DCI) that provides control information for the UE’s downlink operation. As used herein, the phrase “user equipment” is used as a count noun, even though the noun it contains (“equipment”) can be uncountable in ordinary English. Each time instance of a PDCCH SS can be referred to as a monitoring occasion (MO). In New Radio (NR) specifications, to improve system latency and flexibility, the location of each MO can be arbitrary within a slot consisting of 14 or 12 orthogonal frequency-division multiplexing (OFDM) symbols. However, this flexibility increases the PDCCH monitoring complexity of the UE, and a UE capability signaling scheme of the MO pattern per slot can be limited. The network needs to provide a PDCCH SS configuration that defines a set of monitoring occasions that satisfies the declared UE capability. Figure 1A Table 5.2.1-1 of 3GPP specification TR 38.822 describes the corresponding capability signaling. Figure 1A Table 5.2.1-1 of 3GPP specification TR 38.822 describes the corresponding capability signaling. Figure 1B Table 5.2.1-1 of 3GPP specification TR 38.822 describes the corresponding capability signaling.

[0053] Figure 1AThe monitoring spans mentioned in FG3-5b of the table consist of consecutive symbols within a slot, and the intra-slot span pattern is determined based on the monitoring occasion (MO) pattern, the monitoring capability reported by the UE as a set of ordered pairs (X, Y), and the control resource set (CORESET) configuration for the user equipment (UE). Each ordered pair of numbers (X, Y) can be referred to as a “span-gap span-length pair” (where X is a span-gap element and Y is a span-length element). Specifically, the intra-slot spans have the same duration, which is determined by max{maximum of all CORESET durations, minimum of Y among the candidate values reported by the UE}, except for the last span in the slot, which can have a shorter duration. The first span in the intra-slot span pattern starts from the smallest indexed symbol for which the UE is configured with a monitoring occasion. The next span starts with the MO that is not included in the first span, and the same procedure is applied to construct the subsequent spans. The gap between any two consecutive spans, intra-slot and cross-slot, must satisfy the same (X, Y) restriction, where X represents the minimum time gap in OFDM symbols of the two spans, and Y represents the maximum number of consecutive OFDM symbols of each span. In Release 15 (Rel-15), a UE can report its monitoring capability from three possible sets: {(7, 3)}, {(4, 3), (7, 3)}, {(2, 2), (4, 3), (7, 3)}. Figure 1C An example is shown in FIG. 3, where the CORESET configuration has one symbol and the UE reports {(2, 2), (4, 3), (7, 3)}. From the UE’s perspective, a smaller “X” will make monitoring more frequent, i.e., more challenging. This nested capability signaling, i.e., when a UE sends a declaration to the network indicating that it can support a certain X value (or “capability declaration”), means that it can also support the signaling scheme of a larger X value, which is somewhat reasonable because a larger X value is typically less burdensome for the UE. Upon receiving such a capability declaration, the network is expected to send transmissions to the UE that are compliant with the capability declaration, i.e., within the UE’s declared capability to the network.

[0054] In Release 16 (Rel-16) of 3GPP, span-based PDCCH monitoring capability is specified as follows. A UE needs to support a (X, Y) combination selected from (2, 2) (4, 3) (7, 3) as defined in UE feature 3-5b, as a combination (X, Y) of Rel-16 PDCCH monitoring capability per component carrier (per-CC) for the maximum number of non-overlapped control channel elements (CCE) for ultra-reliable low-latency communications uRLLC. The UE reports the combination supported per sub-carrier spacing (SCS), and (2, 2) (4, 3) (7, 3) applies to SCS of 15 kHz and 30 kHz. If the UE reports support of multiple combinations of C(X, Y) for a given SCS, and if multiple combinations of C(X, Y) are valid for a span pattern, the maximum value of the valid combinations C is applied. A combination C(X, Y) is valid if the span pattern satisfies X and Y of the given combination in every slot (including across slot boundaries).

[0055] The span pattern definition of Rel-15 has certain drawbacks, referred to herein as problem 0, problem 1, and problem 2. Problem 0 is related to the span pattern definition not being optimized in Rel-15. Figure 1D An example illustrating this drawback is shown. In Figure 1D , it is assumed that the UE has reported support of multiple combinations {(2, 2), (4, 3), (7, 3)}. The span duration is defined as d span = max(d CORESET，max , minY) = max(2, 2) = 2, resulting in the shown span pattern. d CORESET，max denotes the maximum value of the CORESET length configured to the UE. Although the span pattern satisfies the time interval between the start of two consecutive spans and the upper limit of the span length, it does not satisfy one necessary condition: each MO must be completely contained within one span. As Figure 1D shown, the first MO 130 in the second row is not completely contained within one span. Thus, the derived span pattern is incompatible with the combination. For the same reason, it is incompatible with the other combinations, because the length of the span is determined to be 2 and cannot be changed. The search space configuration described above can not be configured to the UE, even though the UE is obviously capable of monitoring such a configuration by reporting the combination (4, 3). If the span length has been determined to be 3, the PDCCH MO can be monitored according to the combination (4, 3), and a valid span pattern is derived. Thus, the span pattern definition in Rel-15 is not optimized, and the flexibility of the network is unnecessarily limited.

[0056] The second drawback, problem 1, which can also be referred to as hard segmentation of blind detection / control channel element (BD / CCE) constraints across each span of the serving cell, can be understood as follows. For single-cell operation, for a given pair (X, Y), Tables 1 and 2 from TS38.213 (respectively in...) Figure 1E and Figure 1F The table (reproduced) determines the maximum number of PDCCH candidates and non-overlapping CCEs that the UE needs to monitor per time slot for different SCS configurations μ. Specifically, Table 1 shows the maximum number of monitored PDCCH candidates in the span of the span pattern (X, Y) of the downlink (DL) bandwidth portion (BWP) with SCS configuration μ∈{0,1} for a single serving cell. Table 2 shows the maximum number of non-overlapping CCEs in the span of the span pattern (X, Y) of a DL BWP with an SCS configuration μ∈{0,1} for a single serving cell.

[0057] Some constants in these tables have not yet been agreed upon, so they are shown in symbolic form, such as "M01" and "C01". Some embodiments disclosed herein are suitable for use with (i) any of the various combinations of values ​​for these constants or (ii) any combination of values ​​for these constants. The total number of PDCCH candidates for a set of scheduling cells having a parameter set μ and associated pairs (X, Y). Total number of non-overlapping CCEs It remains to be determined.

[0058] The third drawback, issue 2, which can also be referred to as BWP handover and span-based PDCCH monitoring, can be understood as follows. (See Tables 1 and 2.) Figure 1E and 1F (Separately), the span-based PDCCH monitoring introduced in Rel-16 only supports subcarrier spacing (SCS) of 15 kHz and 30 kHz. One reason is that, since higher SCS have shorter slot durations, higher SCS may be associated with shorter slot durations, within which the required latency for uRLLC can be ensured even using slot-based PDCCH monitoring. Another reason is that, due to increased link reliability, uRLLC applications can be served in serving cells with lower frequencies and smaller SCS.

[0059] When using BWP handover, the BWP being handed over may have a different SCS than the previously active BWP. To account for this possibility, it may be advantageous to specify what the UE behavior should be when the network (gNB) switches a BWP to a new BWP with a configuration that does not support span-based monitoring. Therefore, some embodiments provide methods for defining UE behavior for span-based PDCCH monitoring when performing BWP handover.

[0060] In some embodiments, the problem can be addressed by defining the UE's span pattern as follows. For a given set of reported combinations (X, Y) and a set of search space and CORESET configured for the UE by the network, the span pattern is determined as follows. The input is a set A = {(X, Y)} declared (or reported) by the UE and a set of search space and CORESET configured for the UE by the network on the serving cell. The output is the span pattern in the time slot. In some embodiments, the method includes three steps, steps 0, 1, and 2, as follows (step 1 has several sub-steps). Step 0 includes setting the set C of (X, Y) compatible with the configured search space to an empty set C = {}. For each (X, Y) ∈ A, step 1 includes performing three sub-steps as follows: step 1-0, step 1-1, and step 1-2. Step 1-0 includes determining the span duration d. span (Y)=max(d CORESET，max ,Y), where d CORESET，max This is the maximum value of the CORESET length in the CORESET configured for the UE. Step 1-1 includes determining the span pattern as follows for the span duration given in step 1-0: a) generating a bitmap b(l), 0≤l≤13, where b(l) = 1 if any time slot symbol l is part of the monitoring timing, otherwise b(l) = 0. The first span in the span pattern starts from the smallest l in which b(l) = 1. The next span in the span pattern starts from the smallest l not included in the previous spans in which b(l) = 1. The span pattern generated in step 1-1 may be referred to as "the span pattern of assumed span-gap span-length pairs, which includes a first set of control resource sets and a first set of search spaces." Step 1-2 includes placing (X, Y) into C←C ∪{(X, Y)} if the span pattern obtained from step 1-1 satisfies the span condition according to the conditions of the combination (X, Y) that satisfies the span pattern as listed below. Step 2 involves selecting from set C, (i) the set with the maximum value. of (X) ★ Y ★ (i) or (ii) has a maximum value of (X) ★ Y ★ The resulting span pattern is obtained in step 1-1 for patterns with span duration d.span (Y ★ (X, Y) = (X) ★ Y ★ The defined span pattern.

[0061] The following conditions can be used in step 1-1 to satisfy the span pattern for the combination (X, Y). The span pattern can be considered “valid” for the combination (X, Y) if all of the following conditions are met: (i) there is a minimum time interval of X OFDM symbols (including cross-slot boundary cases) between the start of the two spans; (ii) the length of each span is Y consecutive OFDM symbols of the slot; (iii) the spans do not overlap on any OFDM symbols; (iv) each span is contained in a single slot; (v) the same span pattern is repeated in each slot; (vi) the intervals between consecutive spans within and across slots may not be equal, but the same (X, Y) constraint is satisfied by all spans; (vii) each monitoring opportunity is completely contained in one span (i.e., each PDCCH candidate is completely contained in one span); and (viii) for all PDCCH monitoring opportunities in each slot, the number of different start symbol indices of the span does not exceed [a certain value]. (Where X is the minimum value reported by the UE). In the sense that it is a member of the family of span modes that the UE has declared it can handle, any valid span mode can be considered to "conform" to the UE's capability declaration.

[0062] For example, if the UE is configured with Figure 2A The search space configuration shown is invalid for the span pattern derived for (2,2) because one MO is not fully contained within the span. The span pattern derived for (4,3) is valid because it satisfies all the conditions in the table above. The span pattern derived for (7,3) is invalid because the time interval between the start of the first and second spans is 5, which is less than 7.

[0063] In some embodiments, problem 1 can be determined. and The BD / CCE constraint is addressed by distributing different spans across N cells, as shown below. Assume there is a parameter set μ and multiple scheduling cells are scheduled for N scheduling cells (X, Y). As used in this paper, a span pattern is said to be "covered" by (X, Y) if the conditions in FG 3-5b are satisfied for (X, Y). A set of conditions for a combination of (X, Y) satisfying the span pattern is also listed above. Each method taught in this paper for solving problems 1 and 2 can be used to determine the span pattern in Rel-15 or the methods described above as methods for solving problem 0.

[0064] The method to solve problem 1 can use the concept of “aligned span pattern”, which will be discussed in further detail below. In some embodiments, the BD / CCE limit per span can be determined as follows.

[0065] The method referred to herein as Method A can be used to determine the BD limit, as follows. If a UE is configured with Rel-16 PDCCH monitoring capability (with associated combination (X, Y) and SCS configuration μ) for downlink cells, where If the spans on different downlink cells from downlink cells are aligned (i.e., if they together form an aligned span pattern, which will be discussed in further detail below), the UE is not required to monitor more than PDCCH candidates per span on the active DL BWP of a scheduling cell from the scheduling cells, where

[0066]

[0067] is the number of downlink cells for which the UE is configured with Rel-16 monitoring capability (i.e., span-based monitoring capability), is the reference number of serving cells with Rel-16 monitoring capability, and is reported by the UE as capability.

[0068] If the UE indicates the capability to monitor PDCCH according to multiple (X, Y) combinations and the configuration of the UE’s search space sets results in a span pattern with an interval of any two consecutive PDCCH monitoring spans with a value of X equal to or greater than two or more (X, Y) combinations, the associated combination (X, Y) is the one associated with the maximum number of aligned spans.

[0069] The method referred to herein as Method B can be used to determine the non-overlapping CCE limit, as follows. If a UE is configured with Rel-16 PDCCH monitoring capability (with associated combination (X, Y) and SCS configuration μ) for downlink cells, where If the spans on different downlink cells from downlink cells are aligned (i.e., if they together form an aligned span pattern, which will be discussed in further detail below), the UE is not required to monitor more than non-overlapping CCEs per span on the active DL BWP of a scheduling cell from the scheduling cells, where

[0070]

[0071] And is the number of serving cells configured with Rel-16 monitoring capability (i.e., span-based monitoring capability).

[0072] If the UE indicates the capability to monitor PDCCH according to multiple (X, Y) combinations and the configuration of the UE’s search space sets results in a span pattern with intervals of any two consecutive PDCCH monitoring spans equal to or larger than two or more (X, Y) combinations with the value of X, then the associated combination (X, Y) is the one with the maximum number of aligned spans.

[0073] Then, there is still a need to define (i) how to determine the span determination in “per span” mentioned in methods A and B, and (ii) how to determine that the spans on different downlink cells from N downlink cells are aligned. In one embodiment, which can be referred to as embodiment 0-A, the case of aligned spans can be defined as follows. The span pattern on a set of (X, Y) serving cells is considered to be aligned if every two spans on the same or two different cells (i) have the same start and end symbols or (ii) have a time gap between the start of the two spans of at least X symbols. Figure 2B An example is shown in FIG. 4, where a UE is configured with N = 2 serving cells, CC 1 and CC 2, both with (X, Y) = (4, 3). According to embodiment 0-A, the span pattern is classified as aligned.

[0074] In another embodiment, which can be referred to as embodiment 0-B, the case of aligned spans can be defined as follows. The span pattern on a set of (X, Y) serving cells is considered to be aligned if every two spans on the same or two different cells (i) have the same start symbol or (ii) have a time gap between the start of the two spans of at least X symbols. Figure 2CAn example is shown in FIG. 1, where a UE is configured with N = 2 serving cells, CC 1 and CC 2, both with (X, Y) = (4, 3). According to embodiment 0-B, the span pattern is classified as aligned. The definition of aligned span pattern in embodiment 0-B can be alternatively stated as follows. A span pattern in a group of (X, Y) cells can be classified as aligned if for any span in any cell with a start symbol of “i”, any other span in all cells in the group (including the cell itself) should have a start symbol “j” that satisfies “i = j” or “|i - j| >= X”. This rule can be applied within a slot or across slots. Alternatively, for any span in any cell with a start symbol of “i”, there should be no span in any cell in the group (including the cell itself) with a start symbol “j” that does not satisfy “i = j” or “|i - j| >= X”. This rule can be applied within a slot or across slots.

[0075] In another embodiment, which can be referred to as embodiment 0-C, the case of aligned spans can be defined as follows. A span pattern on a group of (X, Y) serving cells is considered to be aligned if every two spans on the same or two different cells (i) have the same ending symbol or (ii) have a time gap between the start of the two spans of at least X symbols. Figure 2D An example is shown in FIG. 1, where a UE is configured with N = 2 serving cells, CC 1 and CC 2, both with (X, Y) = (4, 3). According to embodiment 0-C, the span pattern is classified as aligned.

[0076] The definition of aligned span pattern in embodiment 0-C can be alternatively stated as follows. A span pattern in a group of (X, Y) cells can be classified as aligned if for any span in any cell with an ending symbol of “i”, any other span in all cells in the group (including the cell itself) should have an ending symbol “j” that satisfies “i = j” or “|i - j| >= X”. This rule can be applied within a slot or across slots. Alternatively, for any span in any cell with an ending symbol of “i”, there should be no span in any cell in the group (including the cell itself) with a start symbol “j” that does not satisfy “i = j” or “|i - j| >= X”. This rule can be applied within a slot or across slots.

[0077] In another embodiment, which can be referred to as embodiment 0-C, the case of aligned spans can be defined as follows. A span pattern on a group of (X, Y) serving cells is considered to be aligned if every two spans on the same or two different cells (i) have the same ending symbol or (ii) have a time gap between the start of the two spans of at least X symbols. Figure 2EAn example is shown in Table 1, where a UE is configured with N = 2 serving cells, CC 1 and CC 2, both with (X, Y) = (4, 3). According to embodiment 0-D, the span pattern is classified as aligned. The definition of aligned span pattern in embodiment 0-D can alternatively be stated as follows. A span pattern in a group of (X, Y) cells can be classified as aligned if for any span in any cell with starting symbol “i_start” and ending symbol “i_end”, there is no span in any other cell in the group (including the cell itself) with starting symbol “j_start” and ending symbol “j_end” that does not satisfy “i_start = j_start” or “i_end = j_end” or “|i_start - j_start| >= X”. This rule can be applied within a slot or across slots.

[0078] In another embodiment, which can be referred to as embodiment 1, the case of aligned spans can be defined as follows. A span pattern is determined collectively for (X, Y) cells. This case is classified as aligned if the resulting span pattern is covered by (X, Y). To be covered by (X, Y), a span pattern must have a span in each of the (X, Y) cells. The span in each of the (X, Y) cells must have the same starting symbol and the same ending symbol as the span in the corresponding cell in the span pattern. The span pattern can be determined by the following procedure. The procedure takes as input a set of N downlink cells CC 1, CC 2,..., CC N (with indices 1, 2,..., N), each with an associated pair (X, Y). The procedure includes four steps: Step 1, Step 2, Step 3, and Step 4, as follows. Step 1 includes letting S total / M total For the purpose of this embodiment, a “span” is determined according to the common pattern, not the individual pattern of each cell. According to this embodiment, the following procedure is used to determine whether the spans on different downlink cells of N downlink cells are aligned. The input is a set of N downlink serving cells CC 1, CC 2,..., CC N (with indices 1, 2,..., N), each with an associated pair (X, Y). The procedure includes four steps: Step 1, Step 2, Step 3, and Step 4, as follows. Step 1 includes letting S i i = 1,..., N is the union of all search space sets configured in the serving cell with index i. Step 2 includes defining the set S i ​The union of the sets of all search spaces. The bitmap for determining the span pattern in step 3 is obtained below. Generate a bitmap b(l), 0≤l≤13, where (i) b(l)=1 if any symbol 1 on any slot on any cell in the serving cell group is part of a monitoring occasion and (ii) b(l)=0 otherwise. The first span in the span pattern starts from the smallest 1 (b(l)=1). The next span in the span pattern starts from the smallest 1 (b(l)=1) that is not included in the previous span. Step 3 includes determining the span pattern of a virtual cell with the same numerology as the N cells based on (i) the set of all search spaces S and the obtained bitmap b(l) and (ii) the set of values of {(X,Y)} reported by the UE. The determination is based on Rel-15 span pattern determination. Step 4 includes determining by the UE that the span pattern determined in step 3 is an aligned span pattern if (X,Y) covers the span pattern determined in step 3, otherwise it is not an aligned span pattern.

[0079] Example 1: As shown in Figure 2F , a UE is configured with N=3 serving cells (all with (X,Y)=(4,3)). The MO on CC 1 corresponds to a search space set associated with a length 2 CORESET 200 and a length 3 CORESET 205. The obtained span pattern is determined to be 1110111011000. The associated (X,Y) is equal to (4,3), so this is a (4,3) cell. The MO on CC 2 corresponds to a search space set associated with two length 2 CORESETs and two length 1 CORESETs. The span pattern obtained is 0110011000. Both (2,2) and (4,3) cover this span pattern. But assume (4,3) has a per-span single cell BD / CCE limit greater than (2,2), (4,3) is associated with this cell, so CC 2 is also a (4,3) cell. CC 3 is also configured with two search spaces associated with two different CORESETs. To determine if the span patterns on these three cells are aligned, the procedure of embodiment 1 is employed to consider all MOs (search spaces on all cells) to determine the span pattern of a virtual cell. The span pattern of the virtual cell is found to be 1110110111000 (4,3) is covered, so these two cells are classified as aligned. Thus, in Figure 2F , the three (4,3) cells CC 1, CC 2, and CC 3 are considered to be aligned because the union of the sets of all search space results is covered by (4,3).

[0080] In another embodiment, which can be referred to as embodiment 2, the case of aligned spans can be defined using a single cell to CA (X,Y) conversion as follows. Before applying to the CA hard split equation (the equation specifies and A group of cells is identified by association with the same cell based on the single-cell maximum BD / CCE limit rule. This rule states that if multiple pairs (X, Y) satisfy a span pattern, then a cell is associated with the pair (X, Y) that has the maximum BD / CCE limit per span. As shown below, a span pattern on a virtual cell may not be covered by a pair (X, Y) but may have a new pair (X′, Y′). Figure 2G An example of an alignment with two (4,3) cells and a virtual cell is shown. The virtual cell is not covered by (4,3).

[0081] from Figure 2G It can be seen that the span patterns on CC 1 and CC 2 are covered by two pairs, (2,2) and (4,3). According to the maximum BD / CCE limit rule, both cells are associated as (4,3) cells, and the BD / CCE limit for (4,3) will be applied to each span on these cells in the non-CA case. On the other hand, using CA and hard segmentation, the virtual cell will not be a (4,3) cell, so this will be an unaligned case according to Embodiments 1 and 2. Although (4,3) does not cover the virtual cell, (2,2) does. Because (2,2) also covers each individual cell, a UE behavior will assume that each cell is (2,2) and treat this case as an aligned case. Therefore, based on the non-CA(X,Y) to CA(X,Y) conversion, the following definition of the aligned span pattern can be used: for a set of cells with the same parameter set and the same association pair (X,Y), a span pattern is defined for each cell. In addition, according to Embodiment 1, the virtual cell is defined as a search space set having the union of all SS across all cells. Let P be a pair (X, Y) reported by the UE and let P all Become a subset of P that includes all pairs of coverage span patterns on the virtual cell. If P all If not empty, the search space set is considered to correspond to the aligned span pattern. Virtual cell and a pair (Associated with the maximum single-cell BD / CCE limit per span according to Tables 1 and 2). The alignment case is related to (X). all Y all The span pattern on the virtual cell is associated and applied to all cells.

[0082] for Figure 2G In the example shown, P = P all ={(2, 2)}, therefore, the set of the search space corresponds to the aligned span pattern, with associated pairs (X) all Y all ) = (2, 2) and the span pattern for displaying virtual cells.

[0083] In another embodiment, which may be referred to as Embodiment 3, the applicable span for determining the total BD / CCE limit per span can be defined as follows. Once the span pattern is classified as aligned according to any of Embodiments 0-A, 0-B, 0-C, 0-D, and 1, the monitoring methods given in Methods A and B are... Non-overlapping CCEs or The span of each PDCCH candidate is determined as follows.

[0084] For embodiments 0-A, 0-B, 0-C, or 0-D, for each set of overlapping spans, the span with the longest length is selected to define the per-span limit in method A and method B. The span pattern determined on the virtual cell is used to define each span in method A and method B. In other words, the UE does not need to consider the span determined according to embodiment 0-A, 0-B, 0-C, or 0-D. The activity of the scheduling cell in each downlink cell is monitored more than [number] times per span on the DL BWP. PDCCH candidates or Non-overlapping CCEs.

[0085] For each of Embodiments 1 and 2, in Method A and Method B, the span pattern determined on the virtual cell can be used to define the per-span limit. In other words, the UE does not need to specify the span from the data determined according to Embodiment 1 or 2. The activity of the scheduling cell in each downlink cell is monitored more than [number] times per span on the DL BWP. PDCCH candidates or Non-overlapping CCEs.

[0086] Example 2: This example considers the scenario in Example 1, where the span patterns on the three cells have already been determined to be aligned. The UE does not need to monitor more than [number missing] for each of the first span (i.e., {symbols 0, 1, and 2}), the second span (i.e., {symbols 4, 5, and 6}), or the third span (i.e., {symbols 8, 9, and 10}). PDCCH candidates or Non-overlapping CCEs.

[0087] Example 3: This example considers Figure 2F The situation utilizes (i) SCS configuration μ=0, (ii) UE report for The CA capabilities of each cell are shown in Tables 1 and 2. and (iii) The total number of configured DL cells is in Each cell is associated with (X, Y) = (4, 3) and μ = 0, and (iv) according to methods A and B, such asFigure 2F The total number of resulting PDCCH candidates and non-overlapping CCEs can be determined as follows, given the defined search space configuration, span pattern on each cell, and span pattern on the virtual cell:

[0088]

[0089] And

[0090]

[0091] The following restrictions are thus given. The BD restriction can be given by (i) in the first span, i.e., symbols 0, 1, and 2: {number of PDCCH candidates monitored on CC 1} + {number of PDCCH candidates monitored on CC 2} < 21, (ii) in the second span, i.e., symbols 4, 5, and 6: {number of PDCCH candidates monitored on CC 1} + {number of PDCCH candidates monitored on CC 2} < 21, and (iii) in the third span, i.e., symbols 8, 9, and 10: {number of PDCCH candidates monitored on CC 1} + {number of PDCCH candidates monitored on CC 2} < 21.

[0092] The CCE restriction can be given by (i) in the first span, i.e., symbols 0, 1, and 2: {number of non-overlapping CCEs monitored on CC 1} + {number of non-overlapping CCEs monitored on CC 2} < 42, (ii) in the second span, i.e., symbols 4, 5, and 6: {number of non-overlapping CCEs monitored on CC 1} + {number of non-overlapping CCEs monitored on CC 2} < 42, and (iii) in the third span, i.e., symbols 8, 9, and 10: {number of non-overlapping CCEs monitored on CC 1} + {number of non-overlapping CCEs monitored on CC 2} < 42.

[0093] The following are additional examples of being classified as aligned or unaligned according to embodiment 1. Figure 2H An aligned case is shown: CC 1, CC 2, and CC 3 are classified as aligned because (4, 3) covers the span pattern on the virtual cell. Figure 2I-1 And 2I-2 An unaligned case is shown. This case is different from Figure 2H in that a MO with a length of 2 of a CORESET 210 has been added on CC 3. In this case, (4, 3) no longer covers the resulting span pattern because the time gap between the last span in the first slot and the first span in the second slot is less than 3. Figure 2J is an example of an aligned case: (2, 2) covers the span pattern on the virtual cell. Figure 2Kis an example of a misalignment case: it differs from Figure 2J in that a MO associated with the length 2 CORESET on CC 3 has been added and (2,2) no longer covers the resulting span pattern on the virtual cell.

[0094] Figure 2K The reason why CCs 1, 2 and 3 in are considered misaligned is that the resulting span pattern on the virtual cell is no longer covered by (2,2). This is because, as part of the span definition, it is required that each MO is contained within one span. It can be seen that there is a length 2 MO on CC 3, a part of which appears in the first span of the virtual cell and a part of which appears in the second span of the virtual cell.

[0095] A misaligned span pattern can be handled in the following ways. Once a span pattern is defined as misaligned, it can be specified how PDCCH candidates or non-overlapping CCEs are distributed among the different spans across the cells. To this end, three different interpretations of are provided below.

[0096] In an embodiment, which can be referred to as embodiment 4 or interpretation 1, a uniform distribution can be used. In this embodiment, the UE is not required to monitor more than non-overlapping CCEs or PDCCH candidates across any group of spans from the active DL BWPs of the scheduling cells from the downlink cell, at most one span per scheduling cell, per group. and Both can be based on a capability declaration sent by the UE to the network.

[0097] In an embodiment, which can be referred to as embodiment 5 or interpretation 2, an aligned cell partitioning can be used. In this embodiment, the UE is not required to monitor more than non-overlapping CCEs or PDCCH candidates across any group of spans from the active DL BWPs of the scheduling cells from the downlink cell, where the group of spans are not aligned to each other.

[0098] This group of cells can be associated with (X,Y) such that the resulting span pattern is misaligned, but if some cells are excluded, they would be classified as aligned according to the definitions given in one of embodiments 0-A to 0-D, 2 and 3. In this case, the number of groups of cells can be defined such that the cells in each group are aligned to each other. In Figure 2L (the example of CC 1, CC 2 and CC 3 being misaligned because (2,2) does not cover the virtual cell span pattern according to embodiment 1), cells 1 and 2 are grouped together and cell 3 is grouped alone. and Scaling the number of cells in a group to obtain the total BD / CCE limit per group.

[0099] In some embodiments, cell grouping based on alignment can be used. In a group of N cells with indices 1,..., N, with the same (X, Y) and numerology μ, five steps (Step 0, Step 1, Step 2, Step 3 and Step 4) can be used to form groups of cells as follows.

[0100] Step 0: Perform a set G of cell indices that have not been grouped: G = {1,..., N}

[0101] Step 1: Let G1 be a subset of G with the largest cardinality such that all cells in G1 are classified as aligned. Set G <- G - G1

[0102] Step 2: Set L = 1 the number of groups formed

[0103] Step 3: While G is non-empty

[0104] • L <- L + 1

[0105] • Let G L be a subset of G with the largest cardinality such that all cells in G L are classified as aligned

[0106] • G <- G - G L

[0107] End

[0108] Step 4: Let N l be the cardinality of G l , l = 1,..., L

[0109] • The total BD / CCE limit for the group of cells indexed by G L is determined by

[0110]

[0111] For a group l of N l cells, the BD / CCE limit per span across cells is determined using and instead of and of Embodiment 3.

[0112] In an embodiment, which can be referred to as Embodiment 6 or Explanation 3, time domain span merging can be used. For a group of cells associated with (X, Y) that are classified as unaligned, removing a certain number of spans on certain cells can result in them being classified as aligned. Figure 2MAn example is shown. The span pattern derived in the virtual cell is not covered by (2,2), so this case is considered unaligned. (2,2) does not cover the span pattern because there is an MO that is not fully contained in one of the spans. If the four spans in symbols 1, 2, 3, and 4 are excluded, then all other spans will result in an aligned case. Once these four spans are added, the case will become unaligned. Instead of considering this case unaligned and distributing the BD / CCE limit evenly across all spans according to embodiment 4, it can be beneficial to consider the four spans of symbols 1, 2, 3, and 4 as one "super span" (a method that can be referred to as "span merging") and apply two equations on it, as shown in Figure 2M For each of symbols 5 and 6, symbols 7 and 8, symbols 9 and 10, and symbols 12 and 13, define one separate equation, resulting in four different independent equations.

[0113] The following pseudocode can be used to determine the "super span" set for the set of cells that are classified as unaligned according to any of embodiments 0-a to 2.

[0114] Step 0: Determine the span pattern on the virtual cell. Let L be the number of spans and S i be the i-th span on the virtual cell, i = 1,..., L. S i is a set containing the number of symbols in the i-th span, Define Г as a set containing S i , i.e., Γ = {S1,..., S L}. In Figure 2M , L = 6, S1 = {1, 2}, S2 = {3, 4}, S3 = {5, 6}, S4 = {7, 8}, S5 = {9, 10}, and S6 = {12, 13}.

[0115] Step 1: Run the following procedure only if the "merge condition" is met. The merge condition is met if ("merge condition 1") there is an MO on any cell that is not fully contained in one of the L spans, or ("merge condition 2) there are at least two spans in Γ that do not satisfy the inter-span X condition (including the inter-slot inter-span gap).

[0116] Step 3: In case merge condition 1) is met:

[0117] Find the earliest span such that there is an MO that is not fully contained in the span. Merge this span with the next span to form a new span. The new span includes all symbols from the first symbol of the earliest span to the last symbol of the next span.

[0118] a) Update the span set by removing the two spans and including the new span in the set.

[0119] b) update L to be the number of spans in the set of spans.

[0120] End

[0121] Step 4: When the merge condition 2) is met

[0122] Find the earliest span such that the number of symbols from the beginning of the span to the beginning of the next span is less than X. Merge this span with the next span to form a new span. The new span includes all the symbols in the slot from the first symbol of the earliest span to the last symbol of the next span.

[0123] c) update the set of spans by removing the two spans and including the new span in the set.

[0124] d) update L to be the number of spans in the set of spans.

[0125] End

[0126] Step 5: For l = 1,..., L, define the 1st super span, SP1 l to be the 1st span.

[0127] BD / CCE limit determination: Once the above method has given the set of super spans, Γ, on the virtual cell, the BD / CCE candidates can be distributed across a set of spans, contained in the super span SP i ∈ Γ, of the active DL BWP of the scheduling cell. This can lead to the following specification: For a super span SP i the UE is not required to monitor more than non-overlapping CCEs and more than PDCCH candidates for any set of spans (at most one span per scheduling cell per set) across the active DL BWP of the scheduling cell from downlink cells, where the spans are contained in the super span SP i .

[0128] Take for example that the last set of super spans on the virtual cell includes L = 5 super spans, SP1 = {1, 2, 3, 4}, SP2 = {5, 6}, SP3 = {7, 8}, SP4 = {9, 10} and SP5 = {12, 13}. For the first super span, SP1, there are four spans across the cells: two spans on CC 1, one span on CC 2, one span on CC 3. What the UE is expected to monitor in these spans is shown in the two equations in Figure 2M . For SP2, SP3, SP4 or SP5, there is exactly one span on each cell within the super span. Figure 2M ​

[0129] In some embodiments, problem 2 can be solved using either of two possible approaches to define UE behavior when switching BWP for span-based PDCCH monitoring case. The following embodiments provide two behaviors corresponding to the two possibilities.

[0130] In one embodiment, which can be referred to as embodiment 7, switching to an invalid BWP can be considered as an error case. If a UE is configured with Rel-16 (span-based) PDCCH monitoring for an active BWP on a serving cell, it is not expected that the UE is indicated to switch to a new BWP with a configuration that cannot apply span-based PDCCH monitoring (invalid BWP configuration). For example, a BWP configuration with SCS of 60, 120 or 240 kHz can be an invalid BWP configuration for span-based PDCCH monitoring. It can be seen that embodiment 7 makes it an error case for a UE to be configured with span-based PDCCH monitoring for a cell and invalid configuration for active BWP of the cell.

[0131] As an alternative behavior, the UE can be provided with a fallback operation in case of switching to an invalid BWP. In such an embodiment, which can be referred to as embodiment 8, a fallback UE behavior for switching to an invalid BWP is defined. If a UE is configured with span-based PDCCH monitoring on a serving cell with an active BWP configuration that is applicable for span-based PDCCH monitoring, and if the UE is indicated to switch to a new BWP and the new BWP configuration is invalid for span-based PDCCH monitoring, the UE falls back to slot-based PDCCH monitoring on the new BWP. This is equivalent to the network reconfiguring the cell with slot-based PDCCH monitoring. One example can be a case where a serving cell with SCS = 15 kHz is configured with span-based PDCCH monitoring on an active BWP, where the network indicates to the UE to switch to a new BWP with SCS configured as 120 kHz. After switching to the new BWP, the UE no longer performs span-based PDCCH monitoring, but the UE performs PDCCH monitoring based on slots.

[0132] As mentioned above, if a UE is only configured with monitoringCapabilityConfig-r16 = r16monitoringcapability provided to the UE associated PDCCH candidates in the active DL BWP of the scheduling cell using SCS configuration μ, and of the for PDCCH monitoring in The DL BWP of the activated cell is the active DL BWP of the activated cell, the DL BWP of the deactivated cell is the DL BWP with the index provided by firstActiveDownlinkBWP-Id for the deactivated cell, the UE does not need to monitor more than PDCCH candidates or more than non-overlapping CCEs, (i) if the first condition holds, each span across downlink cells on the active DL BWP of all scheduling cells from the set of downlink cells, or (ii) if the first condition does not hold, across each span on the active DL BWP of all scheduling cells from the set of downlink cells, at most one span per scheduling cell per span, wherein is the number of cells with SCS configuration j. The first condition holds if and only if the union of PDCCH monitoring occasions across all scheduling cells from the set of downlink cells results in PDCCH monitoring according to the combination (X, Y) and any pair of spans in the set is within Y symbols, where the first X symbols start at the first symbol with a PDCCH monitoring occasion, the next X symbols start at the first symbol with a PDCCH monitoring occasion not included in the first X symbols. The first condition holds if the span pattern is an aligned span pattern.

[0133] In the above, the determination of the monitoring capability depends on whether the first condition holds or not. In this way, the UE can check in operation whether the first condition holds or not. As mentioned above, the first condition relates to the union of PDCCH MOs; for example, in Figure 2HExamples of aligned span patterns (i.e., span patterns for which the first condition holds) are shown in FIG. 2. Since the PDCCH MO can vary in different slots, whether a span pattern is an aligned span pattern (i.e., whether the first condition holds) can also vary from slot to slot, and the corresponding PDCCH monitoring capability determination can also vary from slot to slot. In some embodiments, if at least one slot within a group of slots is unaligned, i.e., if at least one slot in the group of slots does not satisfy the first condition, all slots of the group of slots (e.g., a group of up to 2560 slots of an SS configuration) can be defined as unaligned. However, such a definition can increase the processing burden imposed on the UE, since there can be only one unaligned slot among a large number of slots, and thus the UE can need to check a large number of slots (i.e., all slots in the group of slots) before processing any slot in the group of slots. In some embodiments, this processing burden can be alleviated by defining all slots as unaligned only when each slot is unaligned, i.e., only when the first condition does not hold for each slot of the group of slots. While this approach does alleviate the burden on the UE, it also imposes a considerable restriction on the network configuration.

[0134] In other embodiments, the processing burden imposed on the UE can be alleviated if, when any of the slots of a group of slots is unaligned, the unaligned slot occurs with a relatively high frequency. For example, the processing burden imposed on the UE can be alleviated if the network is required to transmit (i) a search space configuration in which all slots are aligned (containing aligned span patterns), or (ii) a search space configuration in which at least one of every P slots is unaligned (where P is a relatively small number, e.g., a number between 3 and 100 (e.g., P = 10)). If the UE can assume that the network will comply with such a requirement, the UE only needs to check any P (e.g., any 10) consecutive slots to determine whether the first condition holds for the entire group of slots.

[0135] In current 3GPP specification (38.331), the periodicity of MO can be up to 2560 slots. In some embodiments, to reduce the burden on the UE, the network is required to send a search space configuration where at least M slots out of every N consecutive slots are misaligned when any slot does not satisfy the first condition (i.e., any slot is not aligned). Alternatively, this behavior can be related to the slot index. For example, the network can be required to send a search space configuration where at least M slots out of every N slots are misaligned when any slot is misaligned, starting from the slot with index N1 that satisfies (N1 mod N) = 0 and ending at the slot with index N2 that satisfies (N2 mod N) = N-1. The duration of a slot depends on the subcarrier spacing, and the frequency of misaligned slots can alternatively be described in absolute time, such as 10 ms or 1 radio frame length. In this case, the network can be required to send a search space configuration where at least M slots out of every T are misaligned when any slot in the search space configuration is misaligned, where T is a time interval (e.g., ms). Alternatively, this behavior can be related to certain time indices, such as subframe index indexed every 1 ms, radio frame index indexed every 10 ms, etc. For example, the network can be required to send a search space configuration where at least M slots out of every radio frame are misaligned when any slot in the SS configuration is misaligned. In some embodiments, to significantly reduce the burden on the UE, N and T are significantly smaller than the duration of 2560 and 2560 slots, respectively.

[0136] In some embodiments where the network communicates with the UE, the methods outlined in Figure 3A (from the network’s perspective) and Figure 3B (from the UE’s perspective) can be performed. With reference to Figure 3A , the network can: receive, from the UE at 305, a capability declaration of the UE; send, to the UE at 310, a first search space (SS) configuration for a first component carrier in a carrier aggregation (CA) scheme; and send, to the UE at 315, a second search space configuration for a second component carrier in the carrier aggregation (CA) scheme. With reference to Figure 3B , the UE can: send, to the network at 320, a capability declaration; receive, from the network at 325, a first search space configuration for a first component carrier in a carrier aggregation (CA) scheme; and receive, from the network at 330, a second search space configuration for a second component carrier in the carrier aggregation (CA) scheme.

[0137] As used herein, an “aligned span pattern” corresponding to multiple sets of monitoring occasions is (i) multiple span patterns, each corresponding to a respective set of monitoring occasions, and all of which are aligned with each other according to the definition of one of the embodiments disclosed herein, or (ii) a span pattern corresponding to the union of the multiple sets of monitoring occasions (i.e., corresponding to a virtual cell configured with the union of the multiple sets of monitoring occasions). As used herein, an “aligned slot” is a slot in which the span pattern is an aligned span pattern, an “unaligned span pattern” is a span pattern that is an unaligned span pattern, and an “unaligned slot” is a slot in which the span pattern is an unaligned span pattern.

[0138] As used herein, a “set” of things is one or more of the things, e.g., a set of control resource sets includes one or more control resource sets, a set of search spaces includes one or more search spaces. As used herein, a “portion” of something means “at least a portion” of the thing, and thus can mean less than all or all of the thing. Thus, a “portion” of a thing includes as a special case the entire thing, i.e., the entire thing is an example of a portion of the thing. As used herein, the word “or” is inclusive, so, for example, “A or B” means any one of (i) A, (ii) B, and (iii) A and B.

[0139] The methods described herein can be performed by one or more processing circuits (e.g., a processing circuit of a network or a processing circuit of a UE). Such processing circuits can be configured to transmit or receive data (e.g., through other elements such as a radio transmitter or receiver). The term “processing circuit” is used herein to refer to any combination of hardware, firmware, and software that processes data or digital signals. Processing circuit hardware can include, for example, application specific integrated circuits (ASICs), general purpose or special purpose central processing units (CPUs), digital signal processors (DSPs), graphics processing units (GPUs), and programmable logic devices such as field programmable gate arrays (FPGAs). In a processing circuit as used herein, each function is performed by either hardware configured to perform that function (i.e., hardwired) or by more general purpose hardware (such as a CPU) configured to execute instructions stored in a non-transitory storage medium. Processing circuits can be fabricated on a single printed circuit board (PCB) or distributed across multiple interconnected PCBs. A processing circuit can contain other processing circuits; for example, a processing circuit can include two processing circuits, an FPGA and a CPU, interconnected on a PCB.

[0140] As used herein, when a method (e.g., adjusting) or a first quantity (e.g., a first variable) is referred to as being “based on” a second quantity (e.g., a second variable), it means that the second quantity is an input to the method or influences the first quantity, e.g., the second quantity can be an input (e.g., one of a number of inputs or the only input) to run a calculation of the first quantity, or the first quantity can be equal to the second quantity, or the first quantity can be the same as the second quantity (e.g., stored in one or more same locations in memory).

[0141] It should be understood that although the terms “first,” “second,” “third,” etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed herein could be termed a second element, component, region, layer or section without departing from the spirit and scope of the inventive concept.

[0142] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the inventive concept. As used herein, the terms “substantially,” “approximately” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent deviations in measured or calculated values that would be recognized by those of ordinary skill in the art. As used herein, unless otherwise expressly provided herein, singular forms “a,” “an” and “the” are intended to include plural forms as well. It will be further understood that the terms “comprises” and / or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Also, use of “can” in describing embodiments of the inventive concept means “one or more embodiments of the inventive concept.” In addition, the term “exemplary” is intended to mean an example or an illustration. As used herein, the terms “using,” “use,” and “used” can be considered synonymous with the terms “utilizing,” “utilize,” and “utilized,” respectively.

[0143] It will be understood that when an element or layer is referred to as being "on", "connected to", "coupled to" or "adjacent to" another element or layer, it can be directly on, connected, coupled or adjacent to the other element or layer or one or more intervening elements or layers can be present. In contrast, when an element or layer is referred to as being "directly on", "directly connected to", "directly coupled to" or "immediately adjacent to" another element or layer, there are no intervening elements or layers present.

[0144] Any numerical range recited herein is intended to include all sub-ranges of the same numerical precision subsumed within the recited range. For example, a range of "1.0 to 10.0" or "1.0 to 10.0" is intended to include all sub-ranges, e.g., 2.4 to 7.6, between and including the recited minimum and maximum values, and, in this example, is intended to cover "1.0 to 3.5", "3.8 to 10.0", and the like. Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein.

[0145] While exemplary embodiments for systems and methods for setting blind detection and control channel element monitoring limitations in a carrier aggregation scheme have been specifically described and illustrated herein, many modifications and variations will be apparent to those skilled in the art. Accordingly, it is to be understood that systems and methods for setting blind detection and control channel element monitoring limitations can be embodied generally by carriers aggregation schemes constructed according to the principles of the present disclosure, not necessarily as described specifically herein. The present application is therefore defined in the following claims and equivalents thereof.

Claims

1. A method executed over a network, comprising: The network receives a capability statement from the first user equipment (UE). The network sends a first search space configuration for the first component carrier in the carrier aggregation scheme to the first UE; The network sends a second search space configuration for the second component carrier in the carrier aggregation scheme to the first UE. in: The first search space configuration defines the first set of monitoring opportunities. The second search space configuration defines the second set of monitoring opportunities; Determine (X, Y) pairs that satisfy both the first set of monitoring opportunities and the second set of monitoring opportunities, wherein the (X, Y) pairs refer to span-gap span-length pairs that conform to the capability declaration of the first UE; Determine the union of the first set of monitoring opportunities and the second set of monitoring opportunities; The span pattern is determined based on the union set; Determine whether the (X, Y) pair is satisfied by the span pattern; and Implement control channel element constraints, wherein the control channel element constraints are based on whether the (X, Y) pair is satisfied by the span pattern.

2. The method according to claim 1, further comprising: The network receives a capability statement from the second user equipment (UE) of the second UE. The network sends a third search space configuration for the first component carrier to the second UE; as well as The network sends a fourth search space configuration for the second component carrier to the second UE. in: The third search space configuration defines a third set of monitoring opportunities. The fourth search space configuration defines the fourth set of monitoring opportunities, and The span pattern corresponding to the third set of monitoring opportunities is not aligned with the span pattern corresponding to the fourth set of monitoring opportunities.

3. The method according to claim 2, wherein, The third search space configuration includes at most the following: There are 10 physical downlink control channel (PDCCH) candidates, among which Based on the capability declaration of the second UE, wherein, Indicates the subcarrier spacing configuration.

4. The method according to claim 2, wherein, The third search space configuration includes at most the following: There are 1 control channel element, of which Based on the capability declaration of the second UE, wherein, Indicates the subcarrier spacing configuration.

5. The method according to claim 1, wherein: The capability declaration of the first UE includes: First span - gap span - length pair, and Second span - gap span - length pair; The method further includes: Determine a first span pattern for the first span-gap span-length pair and for the first set of monitoring timings, wherein the first span pattern is a span pattern assuming that the first span-gap span-length pair includes a first set of control resources and a first set of search spaces; Determine that the first span pattern is valid for the first span-gap span-length pair; Determine a second span pattern for the second span-gap span-length pair and a second span pattern for the first set of monitoring times, wherein the second span pattern is assumed to include the span pattern of the first set of monitoring times; and The second span pattern is determined to be valid for the second span-gap span-length pair.

6. The method according to claim 5, further comprising: The first span-gap span-length pair is determined to correspond to a first specified constant, which specifies the maximum number of PDCCH candidates to be monitored; as well as The second span-gap span-length pair is determined to correspond to a second specified constant, which specifies the maximum number of PDCCH candidates to be monitored, and the second specified constant is greater than the first specified constant.

7. The method according to claim 5, further comprising: Determine that the first span-gap span-length pair corresponds to a first specified constant, wherein the first specified constant specifies the maximum number of non-overlapping control channel elements; as well as The second span-gap span-length pair is determined to correspond to a second specified constant, which specifies the maximum number of non-overlapping control channel elements and is greater than the first specified constant.

8. The method according to claim 1, further comprising: The network instructs the UE to switch to a bandwidth portion that does not support span-based PDCCH monitoring, and The network sends the third search space configuration to the UE. The third search space configuration is a search space configuration used for time slot-based PDCCH monitoring.

9. The method according to claim 1, wherein: When the span pattern is determined to be an aligned span pattern when it covers the (X, Y) pair, the aligned span pattern includes: The first span pattern configured for the first search space, and The second span pattern is used for configuring the second search space, and Every two spans: Having the same start and end symbols, or Between the start of the two spans there is a time gap of the span-gap element of the span-gap span-length pair that is equal to or greater than the capability declared by the first UE.

10. The method according to claim 1, wherein: When the span pattern is determined to be an aligned span pattern when it covers the (X, Y) pair, the aligned span pattern includes: The first span pattern configured for the first search space, and The second span pattern is used for configuring the second search space, and Every two spans: Having the same start symbol, or Between the start of the two spans there is a time gap of the span-gap element of the span-gap span-length pair that is equal to or greater than the capability declared by the first UE.

11. A system including a network, the network including processing circuitry, the processing circuitry being configured to: Receive capability declaration from the first user equipment (UE); Send the first search space configuration for the first component carrier in the carrier aggregation scheme to the first UE; Send the second search space configuration for the second component carrier in the carrier aggregation scheme to the first UE. in: The first search space configuration defines the first set of monitoring opportunities. The second search space configuration defines the second set of monitoring opportunities; Determine (X, Y) pairs that satisfy both the first set of monitoring opportunities and the second set of monitoring opportunities, wherein the (X, Y) pairs refer to span-gap span-length pairs that conform to the capability declaration of the first UE; Determine the union of the first set of monitoring opportunities and the second set of monitoring opportunities; The span pattern is determined based on the union set; Determine whether the (X, Y) pair is satisfied by the span pattern; Implement control channel element constraints, wherein the constraints are based on whether the (X, Y) pair is satisfied by the span pattern.

12. The system according to claim 11, wherein, The processing circuit is further configured to: Receive capability declarations from the second user equipment (UE) from the second UE; Send a third search space configuration for the first component carrier to the second UE; and Send the fourth search space configuration for the second component carrier to the second UE. in: The third search space configuration defines a third set of monitoring opportunities. The fourth search space configuration defines the fourth set of monitoring opportunities, and The span pattern corresponding to the third set of monitoring opportunities is not aligned with the span pattern corresponding to the fourth set of monitoring opportunities.

13. The system according to claim 12, wherein, The third search space configuration includes at most the following: There are 10 physical downlink control channel (PDCCH) candidates, among which Based on the capability declaration of the second UE, wherein, Indicates the subcarrier spacing configuration.

14. The system according to claim 12, wherein, The third search space configuration includes at most the following: There are 1 control channel element, of which Based on the capability declaration of the second UE, wherein, Indicates the subcarrier spacing configuration.

15. The system according to claim 11, wherein: The capability declaration of the first UE includes: First span - gap span - length pair, and Second span - gap span - length pair; The processing circuit is further configured as follows: Determine a first span pattern for the first span-gap span-length pair and for the first set of monitoring timings, wherein the first span pattern is a span pattern assuming that the first span-gap span-length pair includes a first set of control resources and a first set of search spaces; Determine that the first span pattern is valid for the first span-gap span-length pair; Determine a second span pattern for the second span-gap span-length pair and a second span pattern for the first set of monitoring times, wherein the second span pattern is assumed to include the span pattern of the first set of monitoring times; and The second span pattern is determined to be valid for the second span-gap span-length pair.

16. The system according to claim 15, wherein, The processing circuit is further configured to: The first span-gap span-length pair is determined to correspond to a first specified constant, which specifies the maximum number of monitored PDCCH candidates; and The second span-gap span-length pair is determined to correspond to a second specified constant, which specifies the maximum number of PDCCH candidates to be monitored, and the second specified constant is greater than the first specified constant.

17. The system according to claim 15, wherein, The processing circuit is further configured to: The first span-gap span-length pair is determined to correspond to a first specified constant, which specifies the maximum number of non-overlapping control channel elements; and The second span-gap span-length pair is determined to correspond to a second specified constant, which specifies the maximum number of non-overlapping control channel elements and is greater than the first specified constant.

18. The system according to claim 11, wherein, The processing circuit is further configured to: Instruct the UE to switch to a bandwidth portion that does not support span-based PDCCH monitoring, and Send the third search space configuration to the UE. The third search space configuration is a search space configuration used for time slot-based PDCCH monitoring.

19. The system according to claim 11, wherein: When the span pattern is determined to be an aligned span pattern when it covers the (X, Y) pair, the aligned span pattern includes: The first span pattern configured for the first search space, and The second span pattern is used for configuring the second search space, and Every two spans: Having the same start and end symbols, or Between the start of the two spans there is a time gap of the span-gap element of the span-gap span-length pair that is equal to or greater than the capability declared by the first UE.

20. The system according to claim 11, wherein: When the span pattern is determined to be an aligned span pattern when it covers the (X, Y) pair, the aligned span pattern includes: The first span pattern configured for the first search space, and The second span pattern is used for configuring the second search space, and Every two spans: Having the same start symbol, or Between the start of the two spans there is a time gap of the span-gap element of the span-gap span-length pair that is equal to or greater than the capability declared by the first UE.

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