Pdcch blind decoding

Abstract

Example embodiments of the present disclosure are directed to physical downlink control channel (PDCCH) blind decoding. A terminal apparatus determines, from a set of PDCCH candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI. The terminal apparatus further performs at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

Description

PDCCH BLIND DECODINGFIELD

[0001] Various example embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for physical downlink control channel (PDCCH) blind decoding.BACKGROUND

[0002] A communication network may serve as a facility that enables communications between two or more communication devices or provides communication devices access to a data network. A mobile or wireless communication network is one example of a communication network. The communication network may operate in accordance with standards such as those provided by Third Generation Partnership Project (3GPP) or European Telecommunications Standards Institute (ETSI). Examples of standards provided by 3GPP are the so-called 3GPP standards for cellular technology generations, such as 3GPP standards for 4G technology, 5G technology, 6G technology etc.SUMMARY

[0003] In a first aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal apparatus to: determine, from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; and perform at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0004] In a second aspect of the present disclosure, there is provided a method. The method comprises determining, at a terminal apparatus and from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; and performing at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0005] In a third aspect of the present disclosure, there is provided a terminal apparatus. The terminal apparatus comprises means for determining, from a set of physical downlink control channel(PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; and means for performing at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0006] In a fourth aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the second aspect.

[0007] It is to be understood that the Summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Some example embodiments will now be described with reference to the accompanying drawings, where:

[0009] FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

[0010] FIG. 2 illustrates a signaling flow of an example process for PDCCH blind decoding in accordance with some example embodiments of the present disclosure;

[0011] FIG. 3 illustrates a schematic diagram of an example DCI load in accordance with some example embodiments of the present disclosure in accordance with some example embodiments of the present disclosure;

[0012] FIG. 4 illustrates a schematic diagram of an example process of updating prioritized PDCCH candidates in accordance with some example embodiments of the present disclosure;

[0013] FIG. 5 illustrates a signaling flow of an example process for determination and updating of prioritized PDCCH candidates in accordance with some example embodiments of the present disclosure;

[0014] FIG. 6 illustrates a schematic diagram of an example simulation result of PDCCH blind decoding in accordance with some example embodiments of the present disclosure;

[0015] FIG. 7 illustrates a flowchart of a method implemented at a terminal apparatus in accordance with some example embodiments of the present disclosure;

[0016] FIG. 8 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

[0017] FIG. 9 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

[0018] Throughout the drawings, the same or similar reference numerals represent the same or similar element.DETAILED DESCRIPTION

[0019] Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

[0020] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0021] References in the present disclosure to “one embodiment,” “an embodiment,” “an example embodiment,” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0022] It shall be understood that although the terms “first,” “second,”..., etc. in front of noun(s) and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another and they do not limit the order of the noun(s). For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0023] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elementsare joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0024] As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and / or “including”, when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0026] As used in this application, the term “circuitry” may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analog and / or digital hardware circuit(s) with software / firmware and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and(c) hardware ci rcuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0027] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0028] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-loT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), 5.5G, the sixth generation (6G) communication protocols, and / or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0029] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, radio access network (RAN) split architecture comprises a Centralized Unit (CU) and a Distributed Unit (DU) at an IAB donor node. An IAB node comprises a Mobile Terminal (IAB-MT) part that behaves like a UE toward the parent node, and a DU part of an IAB node behaves like a base station toward the next-hop IAB node.

[0030] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT). The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment(LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node). In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0031] As used herein, the term “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other combination of the time, frequency, space and / or code domain resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

[0032] Dynamic scheduling of data channels, e.g., a physical uplink shared channel (PUSCH) and a physical downlink shared channel (PDSCH), may be performed via layer-1 signaling. A PDCCH may provide necessary information for transmission of the PUSCH and reception of the PDSCH such as resource allocation parameters. For example, a UE may acquire time-frequency resources for the transmission and reception via downlink control information (DCI) that is carried via a PDCCH prior to the PUSCH transmission and PDSCH reception.

[0033] However, unlike the PUSCH and PDSCH, in 5G NR, no prior channel is transmitted for scheduling of the PDCCH. Therefore, the UE may perform blind decoding attempts in a search space associated with a set of control resources called “control resource set (CORESET)” and in specific time-frequency locations within the CORESET. The specific locations in the search space(s) potentially carrying the DCI may be referred to as PDCCH candidates. The UE may perform blind decoding over the configured dedicated PDCCH candidates to detect the DCI transmitted from a gNB via a PDCCH of the PDCCH candidates. This procedure may be also referred to as PDCCH blind decoding (BD) in the following for the purpose of discussion.

[0034] In some examples, each CORESET may span over one, two, or three contiguous orthogonal frequency-division multiplexing (OFDM) symbols over multiple resource blocks (RBs), where each RBmay consist of 12 subcarriers. In the frequency domain, a CORESET may span over one or multiple chunks of 6 RBs. A PDCCH candidate may be carried by 1, 2, 4, 8 or 16 control channel elements (CCEs), where the number of CCEs may be defined by an aggregation level (AL). Each CCE may be composed of 6 resource element groups (REGs), and each REG may be 12 resource elements (REs) in one OFDM symbol.

[0035] The PDCCH candidates which need to be monitored by the UE(s) may be configured using so-called search space (SS) sets with each SS set being associated with one CORESET. In NR, there may be two types of SS sets: 1) common SS (CSS) set, commonly monitored by a group of UEs, and 2) UE-specific SS (USS) set, monitored by a specific UE.

[0036] Different configuration settings of a SS set may be specified by various parameters within a search space information element (IE). For example, the configuration settings may include PDCCH monitoring occasions (MOs), i.e., slots and symbols where the SS set exists. The configuration settings may also include the number of PDCCH candidates (e.g., represented by the parameter “nrofCandidates”) that UE needs to perform the blind decoding per aggregation level. The number of PDCCH candidates per AL may directly affect the number of blind decoding attempts that UE needs to perform within every MO. The configuration settings may also include a type of DCI format that the UE expects to receive within the SS set.

[0037] In the current 5G NR specification, CCE indexes of the PDCCH candidates may be determined by the so-called hashing function, which is a function of several configuration parameters. In other words, the UE may identify the PDCCH candidates in the search space based on the hashing function. Then, the UE may perform blind decoding attempts on the PDCCH candidates to detect the DCI(s). However, performing the blind decoding attempts / operation on all of the PDCCH candidates without any preference or priority may cause a large UE energy consumption.

[0038] In accordance with some example embodiments of the present disclosure, there is provided a solution for PDCCH blind decoding. In a method, a terminal apparatus determines, from a set of PDCCH candidates associated with at least one DCI for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI. The terminal apparatus further performs at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0039] In this way, the blind decoding attempts may be performed starting from the prioritized PDCCH candidate(s), such that the efficiency of PDCCH blind decoding can be improved. For example, the UE may not need to perform the blind decoding attempts on all of the PDCCH candidates to detect the DCI(s), i.e., early termination of blind decoding attempts may be achieved for energy saving.

[0040] Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0041] FIG. 1 illustrates an example communication environment 100 in which example embodiments of the present disclosure can be implemented. The network communication 100 comprises one or more terminal apparatuses such as a terminal apparatus 110, and comprises one or more network apparatuses such as a network apparatus 120.

[0042] In some example embodiments, a communication direction from the network apparatus 120 to the terminal apparatus 110 is referred to as a downlink (DL), and a communication direction from the terminal apparatus 110 to the network apparatus 120 is referred to as an uplink (UL). In DL, the network apparatus 120 is a transmitting (TX) apparatus (or a transmitter) and the terminal apparatus 110 is a receiving (RX) apparatus (or a receiver). In UL, the terminal apparatus 110 is a TX apparatus (or a transmitter) and the network apparatus 120 is a RX apparatus (or a receiver).

[0043] Communications in the communication environment 100 may be implemented according to any proper communication protocol (s), comprising, but not limited to, cellular communication protocols, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple (OFDM), Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and / or any other technologies currently known or to be developed in the future.

[0044] In the following, for the purpose of illustration, some example embodiments may be described with the terminal apparatus 110 operating as a terminal device. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0045] It is to be understood that the number of apparatuses and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of apparatuses configured to implement example embodiments of the present disclosure. Although not shown, it would be appreciated that one or more additional apparatuses may be deployed in the communication environment 100. Although illustrated as a base station, the network apparatus 120 may be or may be comprised in any other suitablenetwork device. Although illustrated as a UE, the terminal apparatus 110 may be or may be comprised in any other suitable terminal device.

[0046] FIG. 2 illustrates a signaling flow of an example process 200 for PDCCH blind decoding in accordance with some example embodiments of the present disclosure. For the purpose of illustration, the process 200 will be described with the terminal apparatus 110 and the network apparatus 120.

[0047] In the process 200, the terminal apparatus 110 determines 256, from a set of PDCCH candidates associated with at least one DCI for the terminal apparatus 110, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI. The set of PDCCH candidates may be determined based on the hashing function as discussed above. For example, the network apparatus 120 may transmit 252 configuration(s) of a CORESET and an SS set for the terminal apparatus 110. The terminal apparatus 110 may receive 254 the configuration(s) of the CORESET and SS set, and determine CCE indices of the set of PDCCH candidates by using the hashing function.

[0048] The terminal apparatus 110 further performs 258 at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0049] In various embodiments, the set of PDCCH candidates may be associated with one or more DCIs for the terminal apparatus 110. There may be limits on the number of unicast DCIs that the UE expects to receive in a slot. These limits may be for both self-scheduling cell scenario (i.e., single component carrier) and cross-component carrier scheduling scenario. These limits may be determined based on UE processing capabilities, in terms of total number of blind decoding attempts and total number of CCEs that the UE check for channel estimation on a single slot, so as to impose a reasonable / affordable complexity on the UE. For example, for the scenario of self-scheduling component carrier (single carrier), up to 2 unicast DCIs may be expected for FDD operations, and up to 3 unicast DCIs may be expected for TDD operations. For the scenario of cross-component carrier scheduling, a limited number of unicast DCI may be expected based on UE capability.

[0050] The terminal apparatus 110 may determine, from the set of PDCCH candidates, prioritized PDCCH candidate(s) based on previous blind decoding attempt(s) in an observation window. The observation window may span one or more MOs. For example, the terminal apparatus 110 may determine the prioritized PDCCH candidate(s) based on previous blind decoding attempts in the previous one or more MOs. In some examples, the observation window may include one or more MOs where the terminal apparatus 110 is scheduled. In some examples, the observation window may further include an MO where the terminal apparatus 110 is not scheduled.

[0051] In some embodiments, the terminal apparatus 110 may determine, in the previous blind decoding attempt(s) in the observation window, a previously successfully decoded PDCCH candidate from the set of PDCCH candidates. Based on the previously successfully decoded PDCCH candidate, the terminal apparatus 110 may determine the prioritized PDCCH candidate(s). For example, based on the previous and / or history of prior successful blind decoding attempts, i.e., PDCCH candidates that UE successfully decoded its DCI, the UE may determine, for each unicast DCI from the set of “X” unicast DCIs, at least one PDCCH candidate with higher priority for BD attempt. The previous and / or history of prior successful blind decoding attempts may be in an observation window spanning several past monitoring occasions.

[0052] As an example, the UE may determine the prioritized PDCCH candidate(s) based on a single MO in the observation window. For instance, if the UE has a successful PDCCH blind decoding attempt in the previous MO on PDCCH candidate# , the UE may determine PDCCH candidate# / as the prioritized candidate for the current MO.

[0053] As another example, the UE may determine the prioritized PDCCH candidate(s) based on more than one prior MOs in the observation window. For instance, if the UE in the previous two MOs has successful PDCCH decoding on PDCCH candidate# / and PDCCH candidate# / , the UE may determine two prioritized candidate# / and candidate #Y for starting its BD.

[0054] In some embodiments, the terminal apparatus 110 may determine the prioritized PDCCH candidate based on the previously successfully decoded PDCCH candidate and a relative location in time-frequency domain between a PDCCH candidate of the set of PDCCH candidates and the previously successfully decoded PDCCH candidate.

[0055] As an example, in the process of determining the at least one prioritized PDCCH candidate, the UE may determine that a PDCCH candidate neighboring to the successfully decoded PDCCH candidate may be also the prioritized PDCCH candidate. The UE may determine a limited number of neighboring PDCCH candidates as the prioritized PDCCH candidates. The neighboring PDCCH candidates may be selected in a symmetric or non-symmetric fashion. Different priorities may be assigned to the prioritized PDCCH candidates.

[0056] In some examples, the UE may assign priorities to the neighboring PDCCH candidates in a symmetric fashion according to their relative locations with respect to the prioritized PDCCH candidate in the time-frequency domain. For instance, if the UE determines PDCCH candidate# / as the prioritized candidate, the UE may further determine PDCCH candidate#X-1 and candidate#X+1 as prioritized candidates and candidate#X-2 and candidate#X+2 as prioritized candidates. The candidate# / -! and candidate#X+1 may have lower priorities with respect to candidate# / , but higherpriorities with respect to candidate#X-2 and candidate#X+2.

[0057] In some examples, in the process of determining the at least one prioritized PDCCH candidate, the neighboring PDCCH candidates in ascending / descending order (i.e., in a non-symmetric distribution) may be assigned lower priorities with respect to the successfully decoded PDCCH candidate. For instance, if the UE determines PDCCH candidate#X as the prioritized candidate, the UE may determine that remaining PDCCH candidates in ascending order, i.e., candidate#X+1, candidate#X+2, etc takes lower priorities.

[0058] In some embodiments, in the process of determining the at least one prioritized PDCCH candidate, the terminal apparatus 110 may determine, based on the at least one previous blind decoding attempt, a probability for a PDCCH candidate of the set of PDCCH candidates and the probability indicates a blind decoding success probability of the PDCCH candidate. The terminal apparatus 110 may further determine, based on the probability, the at least one prioritized PDCCH candidate from the set of PDCCH candidates. In other words, the terminal apparatus 110 may determine the prioritized PDCCH candidates based on the blind decoding success probabilities corresponding to the set of PDCCH candidates.

[0059] For example, the UE may construct a list of the probability mass function (PMF) of occurrence associated with each of the set of PDCCH candidates, based on an observation window that spans a sufficiently large number of prior MOs as per network configuration or per UE implementation. Based on that list, the UE may identify N PDCCH candidates that have been decoded successfully at least n times (in relative scale) more than any other candidate. These N PDCCH candidates may be designated as the prioritized candidates. In another alternative implementation, the UE may identify M PDCCH candidates that have been decoded at least m times (in absolute scale) per unit time, that is the UE may identify the M strongest candidates that satisfy a decoding probability criterion. The UE may identify, alternatively or additionally, a combination of the strongest PDCCH candidates in relative and absolute scale, e.g., the PDCCH candidates that are strongest both in relative scale (i.e., stronger than any other PDCCH candidates) and in absolute scale (i.e., candidates that are decoded with sufficiently high probability).

[0060] In an exemplary implementation, the UE may observe a window of, e.g., 100 prior MOs, and record the number of times it has successfully decoded the set of PDCCH candidates, denoted as {candidate#X, candidate#Y, candidate#Z, ...}, thereby forming the frequency of occurrence of each PDCCH candidate. If the UE observes that candidate#X is substantially more frequent than any other candidate (for example, the PMF associated with candidate#X is at least 20% larger than any element of the set {candidate#Y, candidate#Z, ...}, then the UE may designate candidate#X as the prioritizedcandidate. If, in another example, both candidate# and candidate# / are associated with at least 20% larger PMF than any other element of the set {candidate#Z, ...}, then the UE may designate both candidate# / and candidate# / as the prioritized PDCCH candidates.

[0061] It will be appreciated that various ways may be used to determine prioritized PDCCH candidates based on previous PDCCH BD attempts. The scope of the present disclosure is not limited in this regard.

[0062] In some embodiments, the terminal apparatus 110 may determine the at least one prioritized PDCCH candidate in accordance with a determination that a DCI load is below a threshold. In other words, in some embodiments, if the UE determines that the DCI load is below the threshold, the UE may decide to determine the prioritized PDCCH candidate(s).

[0063] The DCI load indicates an estimation of resource occupancy associated with one or more DCIs in a CORESET configured for the terminal apparatus 110. In some embodiments, the DCI load may be determined based on one or more DCIs only scheduled for other terminal apparatus(s). In some embodiments, the DCI load may be determined based on one or more DCIs scheduled for both the terminal apparatus 110 and the other terminal apparatus(s). It is proposed in the present disclosure that if a low DCI load is detected, it is likely that gNB is able to assign to the UE the same PDCCH candidate as previously scheduled MO(s). Thus, the successfully decoded PDCCH candidate may be used to determine prioritized PDCCH candidate(s) for prioritized blind decoding.

[0064] FIG. 3 illustrates a schematic diagram of an example DCI load in accordance with some example embodiments of the present disclosure. FIG. 3 provides illustration of one-UE PDCCH candidates within a CORESET 310 and multiple-UEs PDCCH candidates with different ALs within a CORESET 320. The CORESET 310 and CORESET 320 each have 64 CCEs.

[0065] As illustrated in FIG. 3, in the one-UE case, six PDCCH candidates of UE1 are shown within the CORESET 310 and one of the six PDCCH candidates is actually allocated to carry a DCI. In the multiple-UE case, six PDCCH candidates of UE1 are shown within the CORESET 320 and one of the six PDCCH candidates is actually allocated to carry a DCI. One PDCCH candidate of UE2 is shown within the CORESET 320 and the AL for PDCCH candidate of UE2 is different from the AL for PDCCH candidates of UE1.

[0066] In some embodiments, the terminal apparatus 110 may determine the DCI load by performing energy detection on the CORESET within an MO. In a case where the terminal apparatus 110 determines the DCI load based on at least the DCI (s) scheduled for other terminal apparatus(s), the energy detection on the CORESET may comprise energy detection on a resource not associated withthe set of PDCCH candidates configured for the terminal apparatus. For example, the energy detection may be performed on PDCCH candidates beyond those acquired by the terminal apparatus 110 through the hashing function, such that the terminal apparatus 110 may estimate the number of other DCIs transmitted by the network apparatus 120 within the MO. As an example, the terminal apparatus 110 may perform the energy detection by measuring a reference signal received power (RSRP) value.

[0067] In some embodiments, the threshold may be associated with a configuration of the CORESET, e.g., CORESET size. For example, a larger threshold may be specified for a larger CORESET with a larger number of CCE indices. Alternatively or in addition, the threshold may be associated with an SS set configuration corresponding to the CORESET. For example, a larger threshold may be specified for a common SS set associated with a CORESET shared by a large number of UEs. Alternatively or in addition, the threshold may be associated with a total number of unicast DCIs for the terminal apparatus 110. For example, a larger threshold may be specified if a larger number of DCIs is scheduled for the UE.

[0068] As an example, within a MO, the UE may perform energy detection on the whole CORESET to estimate the number of other DCIs transmitted by the gNB within the current MO. If the energy detected within the MO is below a given threshold (i.e., a low DCI load within the MO), then the UE may continue to determine prioritized PDCCH candidate. Otherwise (i.e., a high DCI load within the MO), the UE may continue to perform BD attempts on all of the set of PDCCH candidates acquired through the hashing function. It will be appreciated that the UE may determine a DCI load in every MO or a limited number of MOs as per UE implementation or network configuration.

[0069] As discussed above, in some embodiments, the at least one prioritized PDCCH candidate may comprise prioritized PDCCH candidates with different priority orders. In this case, the terminal apparatus 110 may perform the blind decoding attempts on the at least one prioritized PDCCH candidates based on the different priority orders. That is, the terminal apparatus 110 may first perform BD attempts on the prioritized PDCCH candidates with higher priority orders and then perform BD attempts on the prioritized PDCCH candidates with lower priority orders.

[0070] In some embodiments, in accordance with a determination that a first number of DCIs are decoded successfully based on the at least one prioritized PDCCH candidate and the first number of DCIs is smaller than a total number of unicast DCIs that the terminal apparatus 110 expects to receive within a slot, the terminal apparatus 110 may perform a blind decoding attempt on a non-prioritized PDCCH candidate in the set of PDCCH candidates.

[0071] For example, the UE may start its BD search algorithm from the identified prioritized PDCCH candidates. If less than X unicast DCIs (i.e., a total number of unicast DCIs that the UE expects toreceive within a slot) are decoded within the prioritized PDCCH candidates, the UE may continue its BD search algorithm on non-prioritized PDCCH candidates.

[0072] In an exemplary implementation, the UE may identify a set of prioritized PDCCH candidates SetP = {candidate#!, ... , candidate#?} and a set of non-prioritized PDCCH candidates SetNP = {candidate#?-*-! , ... , candidate#N}, where N is the total number of PDCCH candidates, and P<N is the number of prioritized PDCCH candidates. Then, the UE may perform the BD search algorithm as follows.

[0073] As an example, a candidate may be selected randomly from SetP and it is searched for a DCI. This step is repeated until all the candidates from SetP are searched, or until X unicast DCIs are successfully decoded. In the former case, the BD search algorithm continues to a next step where a candidate is selected randomly from SetNP and it is searched for a DCI. This step is repeated until all the candidates from SetP are searched, or until X unicast DCIs are successfully decoded. In the latter case, the BD search algorithm is concluded.

[0074] In some embodiments, in accordance with a determination that a total number of unicast DCIs that the terminal apparatus 110 expects to receive within a slot has been decoded successfully, the terminal apparatus 110 may refrain from performing a further blind decoding attempt on the at least one prioritized PDCCH candidate or the set of PDCCH candidates. That is, the UE may terminate its search once X unicast DCIs are decoded without a need to perform BD attempts on all of its PDCCH candidates.

[0075] Alternatively, the terminal apparatus 110 may perform the BD search algorithm on the set of PDCCH candidates. For example, the UE may apply its default BD search algorithm. The UE may terminate its search once X unicast DCIs are decoded, or if it has performed its BD search algorithm on all of its PDCCH candidates. In an exemplary implementation, the UE may apply the BD search algorithm such that a candidate is selected randomly from all PDCCH candidates and it is searched for a DCI. This step is repeated until all the candidates are searched, or until X unicast DCIs are successfully decoded.

[0076] In some embodiments, based on the at least one blind decoding attempt performed by the terminal apparatus 110, the terminal apparatus 110 may determine a further successfully decoded PDCCH candidate. Then the terminal apparatus 110 may update the at least one prioritized PDCCH candidate based on the further successfully decoded PDCCH candidate.

[0077] For example, the UE may store / learn from the successfully decoded PDCCH candidate for each of the X unicast DCIs expected to receive in the current MO. Subsequently, based on the currentMO and the observation window, the UE may update the list of prioritized PDCCH candidate(s) for future MOs.

[0078] FIG. 4 illustrates a schematic diagram of an example process 400 of updating prioritized PDCCH candidates in accordance with some example embodiments of the present disclosure.

[0079] In the example of FIG. 4, it is assumed that there is a single MO per slot and that the UE-specific search space has the periodicity of 4 slots. For simplicity, the PDCCH candidates for only AL=1 is illustrated, but the concept can be easily extended / applied to all ALs that the UE needs to perform BD attempts. It is also assumed that the UE is configured with 5 PDCCH candidates for AL= 1. Also, for MOs that the UE does not have any scheduling DCI, it is assumed that search space set group switching or PDCCH / MO skipping is applied. Therefore, the UE does not need to perform any BDs on the skipped MOs.

[0080] As illustrated in FIG. 4, in slot 0, depending on the UE search algorithm, the UE may need to perform up to 5 BDs for PDCCH candidates of AL=1. Once two DCIs detected / decoded on candidates and candidate#2, the prioritization rule described above may be applied. That is, for every detected candidate# , a list of prioritized candidates for next MO includes candidates# / , # / +1 and # / -1. Therefore, for candidate#!), prioritized candidates are #0 and #1 (#-1 is discarded since it does not on the list of PDCCH candidates), and for candidate#2, the list of prioritized candidates are #2, #1, and #3.

[0081] In the next MO, i.e. , slot 4, the UE may start the BD, for each DCI, from the prioritized list of candidates. With the assumption that the gNB control scheduler load has not been changed much and the gNB can book the UE persistently on the same PDCCH candidates as before, the UE may perform BDs on up to 4 prioritized candidates (sum of the prioritized candidates of each DCI) for detection of 2 DCIs, therefore, to reach 1 / 5= 20% BD reduction.

[0082] Similarly, in slot 12, the list of prioritized PDCCH candidates based on previous successful decoding are PDCCH candidates#!), #1, #2, and UE can save 2 BD attempts.

[0083] Finally, if the load of the gNB control scheduler increases such that the gNB cannot book the UE based on previous PDCCH transmissions, the UE may need to perform BD on all candidates, this is shown in slot 16, where one of the DCI is transmitted outside the list of identified prioritized candidates.

[0084] It will be appreciated that although some embodiments discussed above are with respect to a single AL, the solution of the present disclosure can be easily extended and applied on multiple ALs as well. For example, for a further AL, the terminal apparatus 110 may determine a set of prioritizedPDCCH candidates from the set of PDCCH candidates, and perform a further set of blind decoding attempts on the set of PDCCH candidates starting from the further set of prioritized PDCCH candidates.

[0085] FIG. 5 illustrates a signaling flow of an example process 500 for determination and updating of prioritized PDCCH candidates in accordance with some example embodiments of the present disclosure. The process 500 may be deemed as a detailed example of the process 200. The process 500 involves a gNB 501 and a UE 502. The gNB 501 may be an example of the network apparatus 120 in FIG. 1 and the UE 502 may be an example of the terminal apparatus 110 in FIG. 1.

[0086] As illustrated in FIG. 5, at step 503, the UE 502 provides its capability with regard to the total number (X) of unicast DCIs that it can receive / process within a single slot, for example for CC operation. For instance, it is assumed that X=2.

[0087] At step 504, the UE 502 receives information (i.e., configuration parameters) for a CORESET and a SS set. At step 506, the UE 502 may obtain, i.e., from the received configuration parameters, configuration parameters for a CORESET with 16 CCEs and with an SS information element (IE) indicating a UE-specific SS set. The SS set may have a periodicity of 4 slots.

[0088] Upon reception of configuration parameters, the UE 502 starts checking / monitoring L1 control information reception within the MOs set by the SS set. At step 508, the UE 502 performs energy detection on the SS outside of the PDCCH candidates configured by the hashing function. The UE 502 performs the energy detection as a measure to estimate the load or number of DCIs within the current MO.

[0089] At step 510, the UE 502 performs logical sub-steps to identify at least one prioritized PDCCH candidates, adapt its BD search algorithm and adapt the list of at least one prioritized PDCCH candidates for next MOs.

[0090] FIG. 6 illustrates a schematic diagram of an example simulation result 600 of PDCCH blind decoding in accordance with some example embodiments of the present disclosure. In the example of FIG. 6, the average number of PDCCH BD attempts that the UE performs versus the number of UEs scheduled on a CORESET with 48 CCEs is simulated and illustrated.

[0091] The probability mass function (PMF) for AL distribution is assumed to be [0.4, 0.4, 0.2] for AL=[1 , 2, 4] respectively. The number of PDCCH candidates for AL=[1 , 2, 4] are assumed to be [6, 6, 4], Moreover, it is assumed that “X=1 ”, i.e., the UE expects to receive one unicast DCI within a slot.

[0092] Two different schemes have been considered. In scheme-1, the gNB scheduler does not transmit PDCCH persistently even if it can and UEs does not perform any prioritized BD (solid curve in the figure). On the other hand, in scheme-2, the gNB can potentially book the UE persistently onthe same PDCCH candidates whenever it can and additionally the UEs perform prioritized BD (dashed curve in the figure). As can be seen from the simulation result 600, scheme-2 can achieve on average less BD attempts and therefore consume less power.

[0093] Therefore, with the solution of the present disclosure, the energy consumption at the UE side for performing L1 control operations may be reduced in 6G or future generation. The UE can efficiently decode multiple unicast DCIs within a single slot. The solution can be provided for the case of CC operation. The solution can be extended without distortion of the logical flow also for the case of selfcell scheduling.

[0094] As an example, in a current MO, the UE may perform energy detection on the whole CORESET to estimate the current DOI load. If the DOI load is low, the UE may leverage past successful blind decoding attempts to prioritize PDCCH candidates for future decoding attempts. This prioritization may be based on a single MO or more than one MOs in a larger observation window, considering the frequency of successful decoding on specific candidates.

[0095] Then the UE may initiate its blind decoding search algorithm as follows. The blind decoding starts with the prioritized PDCCH candidates. If the number of DCIs that are decoded is smaller than the total number of DCIs that the UE can receive within a slot, the search continues on the remaining non-prioritized candidates. The search terminates once X DCIs are decoded or all candidates have been searched. In this way, the UE can efficiently decode multiple DCIs, optimizing resource utilization and improving overall system performance.

[0096] FIG. 7 shows a flowchart of an example method 700 implemented at a terminal apparatus in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 700 will be described from the perspective of the terminal apparatus 110 in FIG. 1.

[0097] At block 710, the terminal apparatus 110 determines, from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI.

[0098] At block 720, the terminal apparatus 110 performs at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0099] In some example embodiments, the method 700 further comprises: determining the at least one previous blind decoding attempt from previous blind decoding attempts in an observation window spanning one or more monitoring occasions (MOs).

[0100] In some example embodiments, determining the at least one prioritized PDCCH candidatebased on the at least one previous blind decoding attempt comprises: determining, from the set of PDCCH candidates, a previously successfully decoded PDCCH candidate in the at least one previous blind decoding attempt; and determining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate.

[0101] In some example embodiments, determining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate comprises: determining the at least one prioritized PDCCH candidate based on the previously successfully decoded PDCCH candidate and a relative location in time-frequency domain between a PDCCH candidate of the set of PDCCH candidates and the previously successfully decoded PDCCH candidate.

[0102] In some example embodiments, determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises: determining, based on the at least one previous blind decoding attempt, a probability for a PDCCH candidate of the set of PDCCH candidates, the probability indicating a blind decoding success probability of the PDCCH candidate; and determining, based on the probability, the at least one prioritized PDCCH candidate from the set of PDCCH candidates.

[0103] In some example embodiments, the at least one prioritized PDCCH candidate comprises prioritized PDCCH candidates with different priority orders, and performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: performing blind decoding attempts on the at least one prioritized PDCCH candidates based on the different priority orders.

[0104] In some example embodiments, determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises: in accordance with a determination that a DCI load is below a threshold, determining the at least one prioritized the PDCCH candidates, the DCI load indicating an estimation of resource occupancy associated with one or more DCIs in a control resource set (CORESET) configured for the terminal apparatus.

[0105] In some example embodiments, the method 700 further comprises: determining the DCI load by performing energy detection on the CORESET within an MO, the energy detection on the CORESET comprising energy detection on a resource not associated with the set of PDCCH candidates.

[0106] In some example embodiments, the threshold is associated with at least one of: a configuration of the CORESET, a search space (SS) set configuration corresponding to the CORESET, or a total number of unicast DCIs for the terminal apparatus.

[0107] In some example embodiments, performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: in accordance with a determination that a first number of DCIs are decoded successfully based on the at least one prioritized PDCCH candidate and the first number of DCIs is smaller than a total number of unicast DCIs that the terminal apparatus expects to receive within a slot, performing a blind decoding attempt on a non-prioritized PDCCH candidate in the set of PDCCH candidates.

[0108] In some example embodiments, performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: in accordance with a determination that a total number of unicast DCIs that the terminal apparatus expects to receive within a slot has been decoded successfully, refraining from performing a further blind decoding attempt on the at least one prioritized PDCCH candidate or the set of PDCCH candidates.

[0109] In some example embodiments, the method 700 further comprises: determining, based on the at least one blind decoding attempt performed by the terminal apparatus, a further successfully decoded PDCCH candidate; and updating the at least one prioritized PDCCH candidate based on the further successfully decoded PDCCH candidate.

[0110] In some example embodiments, the method 700 further comprises: determining, for a second aggregation level, a further set of prioritized PDCCH candidates from the set of PDCCH candidates; and performing a further set of blind decoding attempts on the set of PDCCH candidates starting from the further set of prioritized PDCCH candidates.

[0111] In some example embodiments, a terminal apparatus capable of performing any of the method 700 (for example, the terminal apparatus 110 in FIG. 1) may comprise means for performing the respective operations of the method 700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The terminal apparatus may be implemented as or included in the terminal apparatus 110 in FIG. 1.

[0112] In some example embodiments, the terminal apparatus 110 comprises means for determining, from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; and means for performing at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

[0113] In some example embodiments, the terminal apparatus 110 further comprises: means fordetermining the at least one previous blind decoding attempt from previous blind decoding attempts in an observation window spanning one or more monitoring occasions (MOs).

[0114] In some example embodiments, the means for determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises: means for determining, from the set of PDCCH candidates, a previously successfully decoded PDCCH candidate in the at least one previous blind decoding attempt; and means for determining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate.

[0115] In some example embodiments, the means for determining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate comprises: means for determining the at least one prioritized PDCCH candidate based on the previously successfully decoded PDCCH candidate and a relative location in time-frequency domain between a PDCCH candidate of the set of PDCCH candidates and the previously successfully decoded PDCCH candidate.

[0116] In some example embodiments, the means for determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises: means for determining, based on the at least one previous blind decoding attempt, a probability for a PDCCH candidate of the set of PDCCH candidates, the probability indicating a blind decoding success probability of the PDCCH candidate; and means for determining, based on the probability, the at least one prioritized PDCCH candidate from the set of PDCCH candidates.

[0117] In some example embodiments, the at least one prioritized PDCCH candidate comprises prioritized PDCCH candidates with different priority orders, and the means for performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: means for performing blind decoding attempts on the at least one prioritized PDCCH candidates based on the different priority orders.

[0118] In some example embodiments, the means for determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises: means for in accordance with a determination that a DCI load is below a threshold, determining the at least one prioritized the PDCCH candidates, the DCI load indicating an estimation of resource occupancy associated with one or more DCIs in a control resource set (CORESET) configured for the terminal apparatus.

[0119] In some example embodiments, the terminal apparatus 110 further comprises: means for determining the DCI load by performing energy detection on the CORESET within an MO, the energydetection on the CORESET comprising energy detection on a resource not associated with the set of PDCCH candidates.

[0120] In some example embodiments, the threshold is associated with at least one of: a configuration of the CORESET, a search space (SS) set configuration corresponding to the CORESET, or a total number of unicast DCIs for the terminal apparatus.

[0121] In some example embodiments, the means for performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: means for in accordance with a determination that a first number of DCIs are decoded successfully based on the at least one prioritized PDCCH candidate and the first number of DCIs is smaller than a total number of unicast DCIs that the terminal apparatus expects to receive within a slot, performing a blind decoding attempt on a non-prioritized PDCCH candidate in the set of PDCCH candidates.

[0122] In some example embodiments, the means for performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises: means for in accordance with a determination that a total number of unicast DCIs that the terminal apparatus expects to receive within a slot has been decoded successfully, refraining from performing a further blind decoding attempt on the at least one prioritized PDCCH candidate or the set of PDCCH candidates.

[0123] In some example embodiments, the terminal apparatus 110 further comprises: means for determining, based on the at least one blind decoding attempt performed by the terminal apparatus, a further successfully decoded PDCCH candidate; and means for updating the at least one prioritized PDCCH candidate based on the further successfully decoded PDCCH candidate.

[0124] In some example embodiments, the terminal apparatus 110 further comprises: means for determining, for a second aggregation level, a further set of prioritized PDCCH candidates from the set of PDCCH candidates; and means for performing a further set of blind decoding attempts on the set of PDCCH candidates starting from the further set of prioritized PDCCH candidates.

[0125] FIG. 8 is a simplified block diagram of a device 800 that is suitable for implementing example embodiments of the present disclosure. The device 800 may be provided to implement a communication device, for example, the terminal apparatus 110 or the network apparatus 120 as shown in FIG. 1. As shown, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processor 810, and one or more communication modules 840 coupled to the processor 810.

[0126] The communication module 840 is for bidirectional communications. The communication module 840 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 840 may include at least one antenna.

[0127] The processor 810 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[0128] The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 824, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), an optical disk, a laser disk, and other magnetic storage and / or optical storage. Examples of the volatile memories include, but are not limited to, a random-access memory (RAM) 822 and other volatile memories that will not last in the power-down duration.

[0129] A computer program 830 includes computer executable instructions that are executed by the associated processor 810. The instructions of the program 830 may include instructions for performing operations / acts of some example embodiments of the present disclosure. The program 830 may be stored in the memory, e.g., the ROM 824. The processor 810 may perform any suitable actions and processing by loading the program 830 into the RAM 822.

[0130] The example embodiments of the present disclosure may be implemented by means of the program 830 so that the device 800 may perform any process of the disclosure as discussed with reference to FIG. 2 to FIG. 5. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0131] In some example embodiments, the program 830 may be tangibly contained in a computer readable medium which may be included in the device 800 (such as in the memory 820) or other storage devices that are accessible by the device 800. The device 800 may load the program 830 from the computer readable medium to the RAM 822 for execution. In some example embodiments, the computer readable medium may include any types of non-transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. The term “non-transitory,” as usedherein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

[0132] FIG. 9 shows an example of the computer readable medium 900 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 900 has the program 830 stored thereon.

[0133] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. Although various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0134] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non-transitory computer readable medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machineexecutable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[0135] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[0136] In the context of the present disclosure, the computer program code or related data may becarried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[0137] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0138] Further, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, although several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separately or in any suitable subcombination.

[0139] Although the present disclosure has been described in languages specific to structural features and / or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

25WHAT IS CLAIMED IS:

1. A terminal apparatus comprising:at least one processor; andat least one memory storing instructions that, when executed by the at least one processor, cause the terminal apparatus to:determine, from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; andperform at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

2. The terminal apparatus of claim 1 , wherein the terminal apparatus is further caused to: determine the at least one previous blind decoding attempt from previous blind decoding attempts in an observation window spanning one or more monitoring occasions (MOs).

3. The terminal apparatus of claim 1 or 2, wherein determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises:determining, from the set of PDCCH candidates, a previously successfully decoded PDCCH candidate in the at least one previous blind decoding attempt; anddetermining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate.

4. The terminal apparatus of claim 3, wherein determining, based on the previously successfully decoded PDCCH candidate, the at least one prioritized PDCCH candidate comprises:determining the at least one prioritized PDCCH candidate based on the previously successfully decoded PDCCH candidate and a relative location in time-frequency domain between a PDCCH candidate of the set of PDCCH candidates and the previously successfully decoded PDCCH candidate.

5. The terminal apparatus of any of claims 1 to 4, wherein determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises:determining, based on the at least one previous blind decoding attempt, a probability for aPDCCH candidate of the set of PDCCH candidates, the probability indicating a blind decoding success probability of the PDCCH candidate; anddetermining, based on the probability, the at least one prioritized PDCCH candidate from the set of PDCCH candidates.

6. The terminal apparatus of any of claims 1 to 4, wherein the at least one prioritized PDCCH candidate comprises prioritized PDCCH candidates with different priority orders, and performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises:performing blind decoding attempts on the at least one prioritized PDCCH candidates based on the different priority orders.

7. The terminal apparatus of any of claims 1 to 6, wherein determining the at least one prioritized PDCCH candidate based on the at least one previous blind decoding attempt comprises:in accordance with a determination that a DCI load is below a threshold, determining the at least one prioritized the PDCCH candidates, the DCI load indicating an estimation of resource occupancy associated with one or more DCIs in a control resource set (CORESET) configured for the terminal apparatus.

8. The terminal apparatus of claim 7, wherein the terminal apparatus is further caused to: determine the DCI load by performing energy detection on the CORESET within an MO, the energy detection on the CORESET comprising energy detection on a resource not associated with the set of PDCCH candidates.

9. The terminal apparatus of claim 7 or 8, wherein the threshold is associated with at least one of:a configuration of the CORESET,a search space (SS) set configuration corresponding to the CORESET, ora total number of unicast DCIs for the terminal apparatus.

10. The terminal apparatus of any of claims 1 to 9, wherein performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises:in accordance with a determination that a first number of DCIs are decoded successfully based on the at least one prioritized PDCCH candidate and the first number of DCIs is smaller than a totalnumber of unicast DCIs that the terminal apparatus expects to receive within a slot, performing a blind decoding attempt on a non-prioritized PDCCH candidate in the set of PDCCH candidates.

11. The terminal apparatus of any of claims 1 to 9, wherein performing the at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate comprises:in accordance with a determination that a total number of unicast DCIs that the terminal apparatus expects to receive within a slot has been decoded successfully, refraining from performing a further blind decoding attempt on the at least one prioritized PDCCH candidate or the set of PDCCH candidates.

12. The terminal apparatus of any of claims 1 to 11 , wherein the terminal apparatus is further caused to:determine, based on the at least one blind decoding attempt performed by the terminal apparatus, a further successfully decoded PDCCH candidate; andupdate the at least one prioritized PDCCH candidate based on the further successfully decoded PDCCH candidate.

13. The terminal apparatus of any of claims 1 to 12, wherein the at least one prioritized PDCCH candidate, the at least one previous blind decoding attempt, and the at least one blind decoding attempt are specific to a first aggregation level, and the terminal apparatus is further caused to: determine, for a second aggregation level, a further set of prioritized PDCCH candidates from the set of PDCCH candidates; andperform a further set of blind decoding attempts on the set of PDCCH candidates starting from the further set of prioritized PDCCH candidates.

14. A method comprising:determining, at a terminal apparatus and from a set of physical downlink control channel (PDCCH) candidates associated with at least one downlink control information (DCI) for the terminal apparatus, at least one prioritized PDCCH candidate based on at least one previous blind decoding attempt for the at least one DCI; andperforming at least one blind decoding attempt on the set of PDCCH candidates starting from the at least one prioritized PDCCH candidate.

15. A computer readable medium comprising instructions stored thereon for causing an28 apparatus at least to perform the method of claim 14.

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