Control of pdcch search space

Abstract

A method (400) of determining a Physical Downlink Control Channel, PDCCH, search space set for a wireless device is presented. The wireless device is communicatively connected to at least one network device. The PDCCH search space set is configured to 5 indicate a predetermined number of PDCCH candidates (210) across a set of possible aggregation levels. The method (400) comprises estimating (410) an expected signaling condition of the wireless device, determining (420) a customized set of aggregation levels based on the expected signaling condition, and providing (430) a customized search space set for use by the wireless device during an upcoming signaling event. The 0 customized search space set indicating the predetermined number of PDCCH candidates (210) distributed across the customized set of aggregation levels. To be published with Figure 6.

Description

[0001] Control of PDCCH search space

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to Physical Downlink Control Channel (PDCCH) scheduling data and more precisely to determining a search space for a wireless device.

[0004] BACKGROUND

[0005] A Physical Downlink Control Channel (PDCCH) is a control channel used in 4G, 5G and future cellular networks to transmit scheduling information to user equipment (UEs). The PDCCH is a control channel that is mapped to physical resources, such as physical control elements (CCEs) and subcarriers, in a downlink (DL) transmission. The PDCCH carries a Downlink Control Information (DCI) message, which comprise information pertaining to the resources that have been allocated to a specific UE. Such information may comprise indications of a downlink data channel (PDSCH) resource, an uplink data channel (PUSCH) resource, a transmission power etc. The DCI message is scrambled with a random number known as the scrambling code, which is used to protect the message from eavesdropping.

[0006] Each UE is configured with a set of predetermined possible resource assignments that a base station (BS) may select to use for transmitting the PDCCH. Upon scheduling of the PDCCH, resources for the PDCCH are dynamically allocated to each specific UE based on a current channel state and PDCCH reliability requirement of the specific UE. The dynamic resource allocation is performed by the BS and the BS determines which of the predetermined resource assignment alternatives of each UE to utilize. The BS maps the DCI message according to the selected resource assignment. The UE decodes the received information by identifying the selected resource assignment using a process known as blind search.

[0007] In blind search, the UE scans the downlink signal for a PDCCH message, evaluating each of the predetermined set of resource assignments. The UE uses its scrambling code to de-scramble the PDCCH message, and then decodes the DCI message. If the DCI message is successfully decoded, the UE knows which resources have been allocated to it and can begin receiving downlink data and control information.

[0008] SUMMARY

[0009] It is in view of the above considerations and others that the various embodiments of this disclosure have been made. The present disclosure therefor recognizes the fact that there is a need for alternatives to the existing art described above.

[0010] It is an object of some embodiments to solve, mitigate, alleviate, or eliminate at least some of the above or other disadvantages.

[0011] An object of the present disclosure is to provide a new type of scheme for blind search which is improved over prior art and which eliminates or at least mitigates the drawbacks and / or challenges discussed above. More specifically, an object of the invention is to provide a scheme for limiting the number of aggregation levels required to be scanned by a user equipment during blind search whereby a risk for congestion of PDCCH transmissions is reduced. These objects are achieved by the technique set forth in the appended independent claims with preferred embodiments defined in the dependent claims related thereto.

[0012] In a first aspect, a method of determining a Physical Downlink Control Channel, PDCCH, search space set for a wireless device is presented. The wireless device is communicatively connected to at least one network device. The search space set is configured to indicate a predetermined number of PDCCH candidates distributed across a set of possible aggregation levels. The method comprises estimating an expected signaling condition of the wireless device, determining a customized set of aggregation levels based on the expected signaling condition, and providing a customized search space set for use by the wireless device during an upcoming signaling event. The customized search space set indicates the predetermined number of PDCCH candidates distributed across the customized set of aggregation levels. For example, the first aspect enables more efficient use of the PDCCH search space. The first aspect further reduces a risk for congestion of PDCCH transmissions. The first aspect increases PDCCH capacity in terms of number of devices that may be served per cell.

[0013] In one embodiment, the expected signaling condition comprises estimated received signal data comprising an estimated received signal quality and / or an estimated received signal strength. This is for example beneficial as the received signal quality and / or an estimated received signal strength provides a reliable indication of a likelihood that the customized search space may be limited in from an aggregation level perspective.

[0014] In one embodiment, the expected signaling condition comprises a mobility indicator of the wireless device. This is for example beneficial as slow moving, or nonmoving devices are less likely to experience dramatic changes in their radio links making the estimation of the expected signaling condition more reliable.

[0015] In one embodiment, estimating an expected signaling condition comprises processing historic signal data from the wireless device to determine the expected signaling condition. This is for example beneficial as the historic signaling conditions will provide a reliable source of information that may be utilized to, with increased confidence, estimate the expected signaling condition.

[0016] In one embodiment, determining the customized set of aggregation levels comprises, responsive to the expected signaling condition being above a first signaling threshold, exclude one or more aggregation levels from the customized set of aggregation levels, wherein the one or more excluded aggregation levels are aggregation levels of the set of possible aggregation levels requiring highest bandwidth. This is for example beneficial as a comparison to a limit is a processing efficient way of determining if aggregation levels should be excluded or not.

[0017] In one embodiment, the method further comprises estimating an expected traffic condition of the wireless device, wherein the expected traffic condition indicates an expected data rate and an expected burst size of a specific PDU-session of the UE; and determining the customized set of aggregation levels further based on the expected traffic condition. This is for example beneficial as utilizing the expected traffic condition in the decision to exclude aggregation levels may further reduces a risk for congestion of PDCCH transmissions. In one embodiment, estimating an expected traffic condition further comprises obtaining a quality of service flow identifier, 5QI of the specific PDU session, and estimating the expected traffic condition based on the 5QI. This is for example beneficial as the 5QI provides data on expected requirements of the wireless device and utilizing this in the decision to exclude aggregation levels as it may further reduces a risk for congestion of PDCCH transmissions.

[0018] In one embodiment, estimating an expected traffic condition further comprises obtaining a single network slice selection assistance information, S-NSSAI, of the specific PDU session, and estimating the expected traffic condition based on the S- NSSAI. This is for example beneficial as the SNSSAI provides data on expected requirements of the wireless device and utilizing this in the decision to exclude aggregation levels may further reduces a risk for congestion of PDCCH transmissions.

[0019] In one embodiment, determining the customized set of aggregation levels further comprises, responsive to the expected signaling condition being above the first signaling threshold, and the expected traffic conditions indicating a data rate being above a data rate threshold and the expected traffic conditions indicating a burst size being below a burst size threshold, exclude one or more aggregation levels from the customized set of aggregation levels, wherein the one or more excluded aggregation levels are aggregation levels of the set of possible aggregation levels requiring highest bandwidth.

[0020] In one embodiment, determining the customized set of aggregation levels further comprises responsive to the expected traffic conditions failing to indicate a data rate being above the data rate threshold and a burst size being below the burst size threshold, include all aggregation levels from the set of possible aggregation levels in the customized set of aggregation levels. This is for example beneficial as it decrease a risk of decoding failures and missed PDDCH transmissions at the wireless device.

[0021] In some embodiments, determining the customized set of aggregation levels is further based on a Quality of Service (QoS) Flow Identifier, 5QI, associated with the wireless device. Determining the customized set of aggregation levels further comprises responsive to the expected signaling condition being above the first signaling threshold, and the 5QI indicating a data rate being above a data rate threshold and the 5QI indicating a burst size being below a burst size threshold, exclude one or more aggregation levels from the customized set of aggregation levels, wherein the one or more excluded aggregation levels are aggregation levels of the set of possible aggregation levels requiring highest bandwidth. This is for example beneficial as the 5QI provides data on expected requirements of the wireless device and utilizing this in the decision to exclude aggregation levels may further reduces a risk for congestion of PDCCH transmissions.

[0022] In one embodiment, determining the customized set of aggregation levels comprises, responsive to the expected signaling condition being below a second signaling threshold, include all aggregation levels from the set of possible aggregation levels in the customized set of aggregation levels. This is for example beneficial as comparison to a limit is a processing efficient way of determining if aggregation levels should be included or not.

[0023] In one embodiment, determining the customized set of aggregation levels is further based on the 5QI associated with the wireless device and determining the customized set of aggregation levels further comprises, responsive to the 5QI failing to indicate a data rate being above the data rate threshold and a burst size being below the burst size threshold, include all aggregation levels from the set of possible aggregation levels in the customized set of aggregation levels. This is for example beneficial as it decrease a risk of decoding failures and missed PDDCH transmissions at the wireless device.

[0024] In a second aspect, processing circuitry is presented. The processing circuitry is configured to cause execution of the method of the first aspect.

[0025] In a third aspect, a base station, BS, comprising the processing circuitry of the second aspect is presented.

[0026] In one embodiment, the wireless device is a base station (BS).

[0027] In a fourth aspect, a communications network is presented. The communications network comprises a BS configured to communicate with one or more wireless devices and cause execution of the method of the first aspect.

[0028] In a fifth aspect, a computer program product is presented. The computer program product comprises a non-transitory computer readable medium, having thereon a computer program comprising program instructions, the computer program being loadable into processing circuitry and configured to cause execution of the method according to the first aspect when the computer program is run by the data processing unit.

[0029] BRIEF DESCRIPTION OF THE DRAWINGS

[0030] These and other aspects, features and advantages will be apparent and elucidated from the following description of various embodiments; references being made to the appended diagrammatical drawings which illustrate non-limiting examples of how the concept can be reduced into practice.

[0031] Fig. l is a block diagram of a communications network according to some embodiments of the present disclosure.

[0032] Fig. 2A is a block diagram of a communications network according to some embodiments of the present disclosure.

[0033] Fig. 2B is a table of an exemplary search space set according to some embodiments of the present disclosure.

[0034] Fig. 3 is SINR data for cellular network with different number of cells.

[0035] Fig. 4 is a block diagram of a PDCCH search space manager according to some embodiments of the present disclosure.

[0036] Fig. 5 is a flow chart of a determining a PDCCH search space in communications network according to some embodiments of the present disclosure.

[0037] Fig. 6 is a block diagram of a method for determining a PDCCH search space according to some embodiments of the present disclosure.

[0038] Fig. 7 is a block diagram of a computer program product according to some embodiments of the present disclosure.

[0039] Fig. 8 is a block diagram of processing circuitry according to some embodiments of the present disclosure.

[0040] Fig. 9 schematically illustrates a telecommunication network connected via an intermediate network to a host computer.

[0041] Fig. 10 is a generalized block diagram of a host computer communicating via a base station with a user equipment over a partially wireless connection. Figs.11 to 14 are flowcharts illustrating methods implemented in a communication system including a host computer, a base station and a user equipment.

[0042] DETAILED DESCRIPTION

[0043] Hereinafter, certain embodiments will be described more fully with reference to the accompanying drawings. The invention described throughout this disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention, such as it is defined in the appended claims, to those skilled in the art.

[0044] The term ’’coupled” is defined as connected, although not necessarily directly, and not necessarily mechanically. Two or more items that are ’’coupled” may be integral with each other. The terms "a” and ”an” are defined as one or more unless this disclosure explicitly requires otherwise. The terms ’’substantially”, ’’approximately”, and ’’about” are defined as largely, but not necessarily wholly what is specified, as understood by a person of ordinary skill in the art. The terms ’’comprise” (and any form thereof, such as "comprises” and ’’comprising”), ’’have” (and any form thereof, such as ’’has” and ’’having”, ’’include” (and any form thereof, such as ’’includes” and ’’including”) and ’’contain” (and any form thereof, such as ’’contains” and ’’containing”) are open-ended linking verbs. As a result, a method that ’’comprises”, ’’has”, ’’includes” or ’’contains” one or more steps possesses those one or more steps, but is not limited to possessing only those one or more steps.

[0045] Fig. 1 illustrates a communication environment wherein embodiments of the present invention may be employed. A wireless communication device 10, or wireless device 10 for short, of a cellular communications system 1, wireless network 1, communications network 1, or network 1 for short, is in wireless communication with a radio base station (BS) 20 of the cellular communications system 1. The wireless device 10 may be what is generally referred to as a user equipment (UE). The terms wireless device and UE are used interchangeably throughout this disclosure to facilitate the reading of the disclosure. The wireless device 10 is depicted in Fig. 1 as a mobile phone, but may be any kind of device with cellular communication capabilities, such as a tablet or laptop computer, machine-type communication (MTC) device, or similar. Furthermore, a cellular communications system 1 is used as an example throughout this disclosure. However, embodiments of the present invention may be applicable in other types of systems as well, such as but not limited to WiFi systems.

[0046] The BS 20 and UE 10 are examples of what in this disclosure is generically referred to as communication apparatuses. Embodiments are described below in the context of a communication apparatus in the form of the BS 20 or UE 10. However, other types of communication apparatuses can be considered as well, such as a WiFi access point or WiFi enabled device.

[0047] With reference to Fig. 2A, as previously mentioned, the physical layer control channel (PDCCH) 217’ (sometimes referred to as a PDCCH transmission 217’) is responsible for downlink assignments, i.e. information needed for the UE 10 to receive downlink data on the physical downlink shared channel (PDSCH), and uplink grants, i.e. information needed for the UE 10 to transmit data on the physical uplink shared channel (PUSCH). As the UE 10 is unaware of a location of the PDCCH transmission 217’, the UE 10 performs a blind search. In blind search, the UE 10 scans a downlink signal for a PDCCH transmission 217’. The UE 10 searches for the PDCCH transmission 217’ by monitoring a set of possible locations for the PDCCH transmission 217’. Each possible location is referred to as a PDCCH candidate 210, and the set of PDCCH candidates 210 is known as a PDCCH search space set 200, search space set 200 for short. Each PDCCH candidate 210 is a set of control channel resources (CCEs) 217 in which a UE 10 may expect to receive a PDCCH transmission 217' of a certain Downlink Control Information (DCI) format and a certain aggregation level 215. The aggregation level 215 specifies a number of CCEs 217 associated with a specific PDCCH candidate 210, i.e. the number of CCEs 217 that are used to transmit a PDCCH message 217’. For e.g. 5GNR, the higher the aggregation level 215, the more CCEs 217 are used for PDCCH transmission 217’. A set of possible aggregation levels 212 is available to the network 1.

[0048] In 5GNR, the set of possible aggregation levels 212 comprise five aggregation levels 215 which are illustrated in the table of the exemplary search space set 200 of Fig. 2B. As seen from Fig. 2B, a first aggregation level 215 (AL1) uses one CCE 217, a second aggregation level 215 (AL2) uses two CCEs 217, a third aggregation level aggregation level 215 (AL4) uses four CCEs 215, a fourth aggregation level 215 (AL8) uses eight CCEs 215 and a fifth aggregation level 215 (AL 16) uses 16 CCEs 215.

[0049] The aggregation level 215 is chosen by the network 1 for each PDCCH transmission occasion based on traffic conditions and the capabilities of the UE 10. A lower aggregation level 215, i.e. fewer CCEs 217 for the PDCCH transmission 217’, may be utilized in situations wherein traffic conditions are good and the UE 10 has a good signal quality. A higher aggregation level 215, i.e. more CCEs 217 for the PDCCH transmission 217’, increase an amount of redundancy in encoding and thus makes the PDCCH transmission 217’ more robust. Consequently, a higher aggregation level 215 may cause the PDCCH message 217’ to be less vulnerable to interference.

[0050] The UE 10 is configured with search space sets 200 that define a number mio i, n2io 2, n2io 4,n2io 8 , n2io 16 of candidates per aggregation level 215. The collection of candidates 210 for all aggregation levels 215 may be referred to as a set of candidates 205. In Fig. 2B, a first aggregation level 215 (AL1 in Fig. 2B) of the search space set 200 is configured with a first level number of candidates mio i, a second aggregation level 215 (AL2 in Fig. 2B) of the search space set 200 is configured with a second level number of candidates io 2, a third aggregation level 215 (AL4 in Fig. 2B) of the search space set 200 is configured with a third level number of candidates mio 4, a fourth aggregation level 215 (AL8 in Fig. 2B) of the search space set 200 is configured with a fourth level number of candidates mio 4, and a fifth aggregation level 215 (AL16 in Fig. 2B) of the search space set 200 is configured with a fifth level number of candidates mio 16. Consequently, each search space set 200 indicates a number of candidates 210 per aggregation level 215. The UE 10 is further configured to monitor and evaluate all the candidates 210 in the configured search space set 200 once every monitoring occasion. This offers a scheduler of the BS 20 flexibility to choose any of the configured PDCCH candidates 210. The scheduler decides which UEs 10 that are to share a transmission time interval (TTI) (i.e. slot), by means of frequency division multiplexing (FDM). Each of the UEs 10 sharing a slot will require one of the available PDCCH candidates 210. Consequently, if there are many UEs 10 requesting to transmit data, the PDCCH candidates 210 may run out causing increased latency, congestion and reduced bandwidth for of the cellular communications system 1.

[0051] It should be mentioned that, in some examples, different PDCCH candidates 210 may be configured with overlapping CCEs 217. That is to say, different PDCCH candidates 210 may have one or more CCEs 217 in common, i.e. one CCE 217 may be associated with more than one PDCCH candidate 210. This means that, once one PDCCH candidate 210 has been chosen for use by the scheduler, all other PDCCH candidates 210 that happens to comprise a CCE 217 that overlaps with the chosen PDCCH candidates 210 are no longer available. This further increases a risk that the PDCCH candidates 210 may run out causing increased latency, congestion and reduced bandwidth for of the cellular communications system 1. A first PDCCH candidate 210 for a first UE 10 being associated with one more CCEs 217 that are also associated with a second PDCCH candidate 210 for a second UE 10 is an event generally known as PDDCH blocking. The more UEs 10 that are requiring PDCCH transmissions 217’, the higher the risk of PDDCH blocking. If the UEs 10 are likely to require frequent PDCCH transmissions 217’ this also increases the risk of PDCCH blocking.

[0052] A UE 10 requiring a downlink assignment will attempt to locate the PDCCH transmission 217’ by trying to decode a first PDCCH candidate 210 in the search space set 200. In some exemplary implementations, if the decoding is successful, the UE 10 knows that the PDCCH message 217’ is located in the first PDCCH candidate 210. If the decoding is unsuccessful, the UE 10 moves on to the next possible location, i.e. a second PDCCH candidate 210, in the search space set 200. This process continues until the UE 10 either finds the PDCCH message 217’ or has exhausted the entire search space set 200.

[0053] As mentioned, the PDCCH search space set 200 is defined by the cellular communications system 1, specifically by a network part of the cellular communications system 1, i.e. the BS 20 and / or whichever entity that configures the BS 20. Standards governing the cellular communications system 1 generally specify a specific number of PDCCH candidates 210 that are to be indicated by the search space set 200. The cellular communications system 1 may specify the locations of the PDCCH candidates 210. The PDCCH search space set 200 may be considered a dynamic entity that may be changed by the cellular communications system 1 as needed. The cellular communications system 1 may change the size of the PDCCH search space set 200 or the PDCCH candidates 210 based on e.g. current traffic conditions and / or capabilities of the UEs 10 of the cellular communications system 1. Locations of the PDCCH candidates 210 are generally selected to minimize, or at least reduce, an interference between different PDCCH transmissions 217’. However, a size of the PDCCH search space set 200 and the locations of the PDCCH candidates 210 are important factors that affect the performance of the blind search process. A larger PDCCH search space set 200 (more PDCCH candidates 210) means that the UE 10 has to spend more time searching for the PDCCH message 217’, which can delay the start of data transmission. However, a smaller search space set 200 (fewer PDCCH candidates 210) may not be able to accommodate a sufficient number mio i, mio 2, mio 4,n2io s , mio 16 of candidates at each aggregation level 215, which may cause PDCCH blocking.

[0054] The PDCCH search space set 200 is generally defined in the radio resource control (RRC) messages sent to the UE 10. In 5GNR, the PDCCH search space set 200 is defined by the RRC messages SIB1 and PDCCH-Config.

[0055] In 5G systems, communication within a user plane function (UPF) (i.e. communication between the UE 10 and the BS 20) is performed by establishing packet data unit (PDU) sessions. Each PDU-session will have at least one QoS flow at layer-2. Each QoS flow is maped to a QoS profile such that all packets belonging to a specific QoS flow will have the same QoS flow identifier (5QI). An Anchor UPF is maps each downlink packet onto a specific QoS flow (identified by a specific 5QI) belonging to a specific PDU-session. A service data adaptation protocol (SDAP) within the UE 10 maps each uplink packet onto a specific QoS flow (identified by a specific 5QI) belonging to a specific PDU-session. A specific PDU-session may be configured to transfer a specific type of packet, e.g. IPv4, IPv6, IPv4v6, Unstructed or Ethernet packets. The Unstructed category refers to packets without header information which may be advantageous for applications where comparably large volumes of comparably small packets are being transferred. The 5QI is used to identify the different QoS flows that are associated with a specific PDU-session. A specific QoS flow may be categorized in one of three categories, guaranteed bit rate (GBR), non-GBR or delay critical GBR. A specific QoS flow may further specify a default priority level, a packet delay budget, a packet error rate, a default maximum data burst volume and / or a default averaging window. Consequently, a specific 5QI is selected for a specific PDU-session based on requirements of a service requiring the specific PDU-session. For example, a PDU-session for a voice data service will use a different 5QI compared to a PDU- session for a sensor data service (e.g. reporting data from a temperature sensor). When the network 1 is congested, the network 1 may be configured to prioritize traffic based on the QoS flows. This ensures that the most important traffic is given the highest priority.

[0056] In addition to the above, in 5G systems, a PDU-session belongs to a single network slice within the network 1. Network slicing refers to selection and allocation of network resources to suit requirements of a specific service (e.g. high throughput, low latency etc.). Generally, a single network slice selection assistance information (S- NSSAI) is provided to identify a specific network slice. The S-NSSAI comprise a slice / service type (SST) and optionally a slice differentiator (SD). The SST indicates an expected behavior of the specific network slice in terms of features and services supported by the specific network slice. In 5G, the SST is generally configured to indicate one of three service types, enhanced mobile broadband (eMBB), ultra reliable low latency communication (URLLC) or massive machine type communication (mMTC).

[0057] It should be mentioned that time and frequency allocations for different PDCCH candidates 210 may overlap. In such cases a decision from the scheduler of the network 1 to use one candidate for one of the UEs 10 in the network 1 may block the possibility to use other PDCCH candidates 210 to schedule other UEs 10. Consequently, from a scheduling perspective, it is beneficial to have many PDCCH candidates 210 to choose from, since with many PDCCH candidates 210, a risk for ending up without any available PDCCH candidates 210 to schedule a UE 10 (a PDCCH blocking probability) is reduced. The network 1 may adjust the aggregation level 215 to trade off link robustness for resource usage. This is advantageous in order to achieve robust PDCCH performance while avoiding a high PDCCH blocking probability. In addition to this, processing of PDCCH candidates 210 at the UE 10 is resource consuming in terms of cycles, memory, power consumption. For this reason the 5G NR standard has set limits in terms of number of non-overlapping CCEs 217 that a UE 10 can handle and in terms of the maximum number of PDCCH candidates 210 that a UE 210 can process per monitoring occasion. These UE limitations effectively limits the possibility for the network 1 to increase the number of available PDCCH candidates 210 to reduce PDCCH blocking probability.

[0058] In a specific example, system simulations were performed for an exemplary factory scenario. The factory size was 180 m by 90 m by 20m. Different network deployments were considered; from a single cell network up to an eight cell network. An uplink signal-to-noise-plus-interference ratio (SINR) distribution is shown in Fig. 3 where plot A is corresponds to a one cell network, plot B corresponds to a two cell network, plot C corresponds to a four cell network, plot D corresponds to a six cell network and plot E corresponds to an eight cell network. The SINR degrades as the number of cells are increased, this is due to strong inter cell interference in the open factory environment with no isolation between cells, considering the case with four cells, plot C in Fig. 3, the SINR roughly ranges between 0 and 20 dB, with 20% uplink transmissions having SINR less than 5 dB and 80% transmissions having SINR greater than 5 dB. Link level simulations were utilized to map SINR to achievable bitrates on the radio link. The results show that transmitting a small packet of, for example, 80 bytes with a received SINR of 5 dB requires three physical resource blocks (PRBs). For 100 MHz of 5G NR midband spectrum, approximately -270 PRBs may be accommodated. That is to say, from the PUSCH bandwidth point of view, 90 devices may send their packets in one slot. However, practical constraints like PDCCH capacity limits the possibility to multiplex such high number of devices in each slot.

[0059] As mentioned, robustness for PDCCH depends greatly on the aggregation level used, the number of transmit and receive antennas etc. As can be seen from the SINR distributions in Fig. 3, there are several transmissions with SINR lower than 5 dB but a majority of the transmissions have SINR higher than 5 dB. To use resources optimally, the aggregation level 215 is adapted to the quality of the link for each individual UE 10. For the deployment with four cells (plot C in Fig. 3), 80% of the transmissions exhibit an SINR above than 5 dB. This implies that roughly 70 out of 90 UEs 10 would use aggregation level 1 for PDCCH. For a 100 MHz bandwidth, there are 45 CCEs 217. According to the 3gpp specification1, a maximum number of blind decodes per slot that a UE 10 is configured to handle at numerology level 1 is 36. Consequently, there are not enough PDCCH resources to accommodate 70 devices requiring aggregation level 1. So, for such deployment scenarios, performance of the network 1 may not limited by PUSCH bandwidth but rather by PDCCH capacity.

[0060] In Fig. 4, a block diagram of an exemplary PDCCH search space manager 300 is shown. The PDCCH search space manager 300 may be a software implemented PDCCH search space manager 300 provided by processing circuitry of e.g. the network 1, advantageously by a scheduler of the network 1. The PDCCH search space manager 300 is operatively connected to one or more UEs 10 of the network and configured to provide search spaces 200 for the one or more UEs 10. The PDCCH search space manager 300 may provide specific (i.e. specialized) search spaces 200 for each specific UE 10, i.e. a search space set 200 configured for a specific UE 10. That is to say the search space set 200 provided by the PDCCH search space manager 300 may be adapted for a specific UE 10. The search space set 200 is configured to indicate a predetermined number 305 of possible locations of PDCCH transmissions 217’ distributed across a set of customized aggregation levels 325, sometimes referred to as allowed aggregation levels 325 or permitted aggregation levels 325. That is to say, the PDCCH search space manager 300 is configured to indicate a predetermined number of PDCCH candidates 210. The predetermined number may, as previously indicated, be any number but advantageously correspond to the maximum number of blind decodes per slot indicated by 3gpp.

[0061] The PDCCH search space manager 300 comprises a PDCCH search space estimator 310. The PDCCH search space estimator 310 is configured to, based on signal data 11 associated with the specific UE 10, estimate a signaling condition 315 for the UE 10. The PDCCH search space manager 300 further comprises a PDCCH search space determiner 320. The PDCCH search space determiner 320 is configured to, based on the estimated signaling condition 315, determine the possible aggregation levels

[0062] 13GPP TS 38.211 v. 17.6.0, table 4.2-1 325. The PDCCH search space manager 300 further comprises a PDCCH search space provider 330. The PDCCH search space provider 330 is configured to provide a customized search space set 335 to the UE 10. The customized search space set 335 is based on the possible aggregation levels 325.

[0063] As mentioned, the PDCCH search space estimator 310 is configured to estimate the current signal condition 315 based on signal data 11 of the UE 10. The signal data 10 may comprise any relevant signal data, directly or indirectly, relevant for estimating the signaling condition 315 for the UE 10. The signal data 11 may be obtained from the UE 10 and / or from the network 1. In some examples, the signal data 11 is obtained by measuring one or more parameters at the PDCCH search space manager 300. The signal data 10 may comprise radio link data, signaling condition data and / or RF quality data, some specific, non-limiting examples may be signal strength, SINR, Interference levels, channel conditions, link bandwidth, modulation scheme and coding rate, transmission power, received power, packet loss rate, bit error rate, received signal strength indicator (RS SI), reference signal received power (RSRP), channel quality indicator (CQI), received cumulative signal-to-noise ratio (RCINR) etc.

[0064] In some example, the estimated signal condition 315 may comprise estimated received signal data 316. The estimated received signal data 316 may be based on historic signal data 345 of the UE 10. That is to say, the PDCCH search space estimator 310 may be configured to process the historic signal data 345 of the UE 10 to estimate the estimated signal condition 315. The historic signal data 345 may be obtained from a storage device 340 operatively connected to the PDCCH search space manager 300. The PDCCH search space manager 300 may be configured to store signal data 11 of the UE 10 at the storage device 340 as historic signal data 345 associated with the UE 10. The estimated received signal data 316 may be estimated based on a x:th percentile of a distribution of historic data 345. The x:th percentile may be a 15 :th percentile or lower, a 10:th percentile or lower, a 5:th percentile or lower, or a 1 :st percentile or lower. The historic data 345 may comprises historic samples from a relatively long time period e.g. seconds or minutes. Additionally, or alternatively, the estimated received signal data 316 may be estimated on AI / ML methods trained on e.g. the historic data 345. The estimated received signal data 316 may comprise an estimated received signal strength and / or an estimated received signal quality. In some examples, the estimated received signal data 316 comprises an estimated SINR.

[0065] The PDCCH search space estimator 310 may be configured to estimate signal conditions 315 based on UE mobility data 317. The UE mobility data 317 may indicate a probability that the UE 10 will move within a predetermined time frame. The UE mobility data 317 may be obtained based on e.g. deployment of each UE. In some examples, the mobility data 317 is configured to whether the UE 10 is to be considered immobile, e.g. attached to a machine, a wall, etc., or mobile, e.g. attached to a moving robot, an automated guided vehicle (AGV) etc. Such data may be created as part of the configuration parameters used to set up the network deployment. In some examples, the UE mobility data 317 is estimated based on the historic data 345.

[0066] In some examples, the PDCCH search space estimator 310 is further configured to estimate an expected traffic condition 318 for the UE 10. The expected traffic condition 318 advantageously indicate an expected traffic condition for a specific PDU-session 15 of the UE 10. The PDCCH search space estimator 310 may be configured to obtain a 5QI 12 associated with the specific PDU-session 15 and estimate the expected traffic condition 318 based on the 5QI 12. Additionally, or alternatively, the PDCCH search space estimator 310 may be configured to obtain an N-NSSAI 13 associated with the specific PDU-session 15 and estimate the expected traffic condition 318 based on the N-SSAI 13. The expected traffic condition 318 generally indicate, directly or indirectly via e.g. the 5QI 12 and / or SST of the S-NSSAI 13, an expected data rate and an expected burst size of the specific PDU-session 15.

[0067] As previously mentioned, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation levels 325 based on the estimated signaling condition 315. Generally, the PDCCH search space determiner 320 is configured to limit the customized set of aggregation levels 325 to only indicate the lower aggression levels 215 if the estimated signaling condition 315 are good. If the estimated signaling condition 315 are considered good, it is likely that the UE 10 will be able to receive a PDCCH transmission 217’ at an aggregation level 215 having fewer CCEs 217. This allows the bandwidth efficient PDCCH transmission 217’ (the PDCCH transmission 217’ utilizing fewer CCEs 217) to be utilized by UEs 10 being likely to be able to receive them leaving the more PDCCH transmission 217’ for possible reception by UEs 10 having comparably worse estimated signaling condition 315.

[0068] To this end, PDCCH search space determiner 320 may determine the customized set of possible aggregation levels 325 in any suitable way. In some examples, the PDCCH search space determiner 320 may be configured to compare the expected signaling condition 315 to an associated first signaling threshold 301. If the expected signaling condition 315 is above the first signaling threshold 301, i.e. the expected signaling condition 315 is better than the first signaling threshold 301, this indicate that the UE 10 is unlikely to require an abundance of CCEs 217 for decoding the PDCCH transmission 217’. This allows the PDCCH search space determiner 320 to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The one or more excluded aggregation levels 215 may be aggregation levels 215 of the set of possible aggregation levels 212 that require a highest bandwidth. That is to say, the customized set of aggregation levels 325 may be limited to comprise only aggregation levels 215 of the set of possible aggregation levels 212 that require comparably low bandwidth.

[0069] Assuming the network 1 is a 5GNR network, the fifth aggregation level 215 may be excluded from the customized set of aggregation levels 325 if the expected signaling condition 315 is above the first signaling threshold 301. That is to say, the fifth level number of candidates mio 16 may be set to zero. In some examples, if the expected signaling condition 315 is above the first signaling threshold 301 by more than a first predetermined delta, also the fourth aggregation level 215 may be excluded from the customized set of aggregation levels 325. That is to say the fourth level number of candidates mio s may be set to zero. In some examples, if the expected signaling condition 315 is above the first signaling threshold 301 by more than a second predetermined delta, being greater than the first predetermined delta, also the third aggregation level 215 may be excluded from the customized set of aggregation levels 325. That is to say the third level number of candidates mio 4 may be set to zero.

[0070] Reducing the fifth level number of candidates mio 16 by one will free up a number of CCEs 217 that will allow e.g. the first level number of candidates mio i to be increased. This will increase the number of PDCCH candidates 210 of the customized search space set 200. It should be mentioned, that, in some examples, the respective number of candidates io i, mio 2, mio 4,n2io s, mio 16 may not be set to zero but rather reduced to free candidates at aggregation levels 215 requiring fewer CCEs 217.

[0071] In some examples, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation level 325 based on the UE traffic condition 318. If the traffic condition 318 indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, this indicate that the UE 10 is likely to generate comparably small data packets comparably frequently. This implies that the UE 10 is likely to require frequent PDCCH transmissions 217’. To this end, if the traffic condition 318 indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, the PDCCH search space determiner 320 may be configured to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0072] In some examples, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation level 325 based on the 5QI 12 associated with a specific PDU-session 15 of the UE 10. If the 5QI 12 indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, this indicate that the UE 10 is likely to generate comparably small data packets comparably frequently. This implies that the UE 10 is likely to require frequent PDCCH transmissions 217’. To this end, if the 5QI 12 indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, the PDCCH search space determiner 320 may be configured to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0073] Advantageously, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation level 325 based on both the first signaling threshold 301 and the 5QI 12. This means that if the expected signaling condition 315 is above the first signaling threshold 301 and the 5QI 12 indicates a data rate being below data rate threshold and / or a burst size being below a burst size threshold, the PDCCH search space determiner 320 may determine to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0074] In some examples, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation level 325 based on the S-NSSAI 13 associated with a specific PDU-session 15 of the UE 10. If the S-NSSAI 13 (or specifically the SST of the S-NSSAI 13) indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, this indicate that the UE 10 is likely to generate comparably small data packets comparably frequently. This implies that the UE 10 is likely to require frequent PDCCH transmissions 217’. To this end, if the S-NSSAI 13 indicates a data rate being above a data rate threshold and a burst size being below a burst size threshold, the PDCCH search space determiner 320 may be configured to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0075] Advantageously, the PDCCH search space determiner 320 is configured to determine the customized set of aggregation level 325 based on both the first signaling threshold 301 and the S-NSSAI 13. This means that if the expected signaling condition 315 is above the first signaling threshold 301 and the S-NSSAI 13 indicates a data rate being below data rate threshold and / or a burst size being below a burst size threshold, the PDCCH search space determiner 320 may determine to exclude one or more high bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0076] Additionally, or alternatively, the PDCCH search space determiner 320 may be configured to compare the expected signaling condition 315 to a second signaling threshold 302. The second signaling threshold 302 is lower than the first signaling threshold 301. If the expected signaling condition 315 is below the second signaling threshold 302, this may indicate that the UE 10 is at poor signaling conditions and it is unlikely to receive a PDCCH transmission 217’ of the lower numbers of CCEs 217. To this end, if the expected signaling condition 315 is below the second signaling threshold 302, the PDCCH search space determiner 320 may be configured to include all aggregation levels 315 from the set of possible aggregation levels 212 in the customized set of aggregation levels 325. Alternatively, if the expected signaling condition 315 is below the second signaling threshold 302, the PDCCH search space determiner 320 may be configured to exclude one or more low bandwidth aggregation levels 315 from the set of possible aggregation levels 212 in the customized set of aggregation levels 325. That is to say, the customized set of aggregation levels 325 may be limited to comprise only aggregation levels 215 of the set of possible aggregation levels 212 that require comparably high bandwidth.

[0077] Assuming the network 1 is a 5G NR network, aggregation level 1 may be excluded from the customized set of aggregation levels 325 if the expected signaling condition 315 is below the second signaling threshold 302. In some examples, if the expected signaling condition 315 is below the second signaling threshold 302 by more than the first predetermined delta, also aggregation level 2 may be excluded from the customized set of aggregation levels 325. In some examples, if the expected signaling condition 315 is below the second signaling threshold 302 by more than a second predetermined delta, being greater than the first predetermined delta, also aggregation level 3 may be excluded from the customized set of aggregation levels 325.

[0078] Correspondingly to the example given above, if the 5QI 12 indicates a data rate being above the data rate threshold and / or a burst size being above the burst size threshold, the PDCCH search space determiner 320 may be configured to exclude one or more low bandwidth aggregation levels 215 from the customized set of aggregation levels 325. The exclusion may be conducted as indicated in examples given above.

[0079] As mentioned, the PDCCH search space provider 330 is configured to provide the customized search space set 335 to the UE 10. The customized search space set 335 is advantageously provided to the UE 10 according to suitable standards governing communication of the network 1. The predetermined number 305 of possible locations of PDCCH transmissions 217’, i.e. the predetermined number 305 of PDCCH candidates 210, is, as mentioned, generally a network specific parameter. To exemplify, in 5GNR, the maximum number 305 of PDCCH candidates 210 for blind search is dependent on a sub-carrier bandwidth (SCS) and a configuration of the PDCCH transmission 217’. The PDCCH search space provider 330, the PDCCH search space manager 300 or any other suitable circuitry may be configured to distribute a predetermined number 305 of PDCCH candidates 210 across the customized set of aggregation levels 325. The distribution of the predetermined number 305 of PDCCH candidates 210 may be performed according to suitable standards governing communication of the network 1. In some examples, the distribution of the predetermined number 305 of PDCCH candidates 210 may be evenly across the across the customized set of aggregation levels 325.

[0080] The PDCCH search space manager 300 may be configured to determine the PDCCH search space set 200 for specific wireless devices 10 individually, i.e. one PDCCH search space set 200 may be determined for one specific wireless 10 of the network 1. Additionally, or alternatively, the PDCCH search space manager 300 may be configured to determine a PDCCH search space set 200 for a group of UEs 10. The UEs may be grouped based on e.g. one or more of a type of device, historic data 345, mobility data 317 etc.

[0081] In Fig. 5, a flow chart of a non-limiting, exemplary process flow for determining a PDCCH search space set 200 in a network 1. At an optional first processing point Pl, it is determined if there are comparably many devices within a current cell of the network 1 that transmit and / or receive comparably small packets. If, at a first decision point DI, it is true that here are comparably many devices within the current cell of the network 1 that transmit and / or receive comparably small packets, the process proceeds to a second processing point P2. At the second processing point P2, a UE 10 is selected for processing. The selected UE 10 is selected from all UEs 10 within a current cell of the network 1 that has not been processed within a predetermined time. At the third processing point P3, a long term prediction of the previously mentioned x:th percentile SINR is formed based on historic data 345 of the UE 10. If, at a second decision point D2, it is true that the x:th percentile SINR is greater than the first threshold value 301, the process proceeds to an optional third decision point D3. If, at the third decision point D3, it is determined that the UE 10 is immobile (i.e. the UE mobility data 317 indicate immobility) the process proceeds to the fourth processing point P4. At the fourth processing point P4, the UE 10 is configured with a search space set 200 that contains only lower aggregation levels 215 (e.g. aggregation levels 1, 2, 4 for 5G NR). If, at a fourth decision point D4, it is determined that all UEs 10 of the cell have been processed, the process ends.

[0082] If, at the first decision point DI, it is false that here are comparably many devices within the current cell of the network 1 that transmit and / or receive comparably small packets, the process proceeds to a fifth processing point P5. Also, if, at the second decision point D2, it is false that the x:th percentile SINR is greater than the first threshold value 301, the process proceeds to the fifth processing point P5. Further, if, at the third decision point D3, it is determined that the UE 10 is mobile (i.e. the UE mobility data 317 indicate mobility) the process proceeds to the fifth processing point P5. At the fifth processing point P5, the UE 10 is configured with a search space set 200 that contains all aggregation levels 215 of the set of possible aggregation levels 202.

[0083] It may be concluded that traffic patterns involving relatively small data bursts, arriving at the network 1 ingress with inter-arrival times in the order of 10 ms, with associated tight latency and reliability requirements need to be handled by the network 1. Capacity in terms of number of devices that may be served within a coverage area of a network 1 may be limited by PDCCH capacity. One further bottle-neck for the PDCCH capacity is limitations in terms of UE processing. In fact, even if more radio resources (time and frequency) were allocated to the PDCCH, i.e. even if a control region is increased, a full potential for increase in PDCCH capacity cannot be reached without the proposed disclosure.

[0084] With reference to Fig. 6, an exemplary method 400 of determining a PDCCH search space set 200 for a wireless device 10 is presented. The method 400 may be expanded, modified or otherwise reworked to comprise any feature, function or example presented herein.

[0085] The wireless device 10 is communicatively connected to at least one network device 20. The search space set 200 is configured to indicate a predetermined number 305 of possible locations of PDCCH transmissions 217’ distributed across a set of possible aggregation levels 212.

[0086] The method 400 comprises estimating 410 an expected signaling condition 315 of the wireless device 10. The estimating 410 may be performed as exemplified in reference to the PDCCH search space manager 300, specifically the PDCCH search space estimator 310. In some examples, the estimating 410 comprises processing of historic signal data 336 from the wireless device 10 to determine the expected signaling condition 315.

[0087] The method 400 further comprises determining 420 a customized set of aggregation levels 325 based on the expected signaling condition 315. The determining 420 may be performed as exemplified in reference to the PDCCH search space manager 300, specifically the PDCCH search space determiner 320. In some examples, the determining 420 comprises, responsive to the expected signaling condition 315 being above a first signaling threshold 301, excluding one or more aggregation levels 215 from the customized set of aggregation levels 325. The one or more excluded aggregation levels 215 are aggregation levels 215 of the set of possible aggregation levels 212 requiring highest bandwidth. Additionally, or alternatively, the determining 420 may comprise, responsive to the expected signaling condition 315 being below the second signaling threshold 302, including all aggregation levels 215 from the set of possible aggregation levels 212 in the customized set of aggregation levels 325.

[0088] The method 400 further comprises providing 430 the customized search space set 335 for use by the wireless device 10 during an upcoming signaling event. The customized search space set 335 indicating the predetermined number 305 of PDCCH candidates 210 distributed across the customized set of aggregation levels 325. The determining 420 may be performed as exemplified in reference to the PDCCH search space manager 300, specifically the PDCCH search space provider 330.

[0089] In Fig. 7, an exemplary computer program product 500 is shown. The computer program product 500 comprises a non-transitory computer readable medium 600 such as, for example, a universal serial bus (USB) memory, a plug-in card, an embedded drive, or a read only memory (ROM). Figure 7 illustrates an example computer readable medium 600 in the form of a vintage 5,25” floppy disc. The computer readable medium 600 has stored thereon a computer program comprising 700 program instructions 710. The computer program may, when loaded into, and run by, suitable processing circuitry, cause execution of some or all of the method steps, features or examples according to, for example, the method 400 illustrated in Fig. 6, or otherwise described herein.

[0090] As schematically shown in Fig. 8, The computer program 700 is loadable into a processing circuitry 800, which may, for example, be comprised in a BS 20 any other suitable wireless device. When loaded into the processing circuitry 800, the computer program 700 may be stored in a memory associated with, or comprised in, the data processor 800. According to some embodiments, the computer program 700 may, when loaded into, and run by, the data processing circuitry 800, cause execution of some or all of the method steps, features or examples according to, for example, the method 400 illustrated in Fig. 6, or otherwise described herein.

[0091] The processing circuitry 800 may be said to be configured to cause execution of some or all of the method steps, features or examples according to for example the method 400 illustrated in Fig. 6 or otherwise described herein.

[0092] With reference to Fig. 9, in accordance with an embodiment, a communication system includes a telecommunication network 3210, such as a 3GPP-type cellular network, which comprises an access network 3211, such as a radio access network, and a core network 3214. The access network 3211 comprises a plurality of base stations 3212a, 3212b, 3212c, such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 3213a, 3213b, 3213c. Each base station 3212a, 3212b, 3212c is connectable to the core network 3214 over a wired or wireless connection 3215. A first user equipment (UE) 3291 located in coverage area 3213c is configured to wirelessly connect to, or be paged by, the corresponding base station 3212c. A second UE 3292 in coverage area 3213a is wirelessly connectable to the corresponding base station 3212a. While a plurality of UEs 3291, 3292 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 3212.

[0093] The telecommunication network 3210 is itself connected to a host computer 3230, which may be embodied in the hardware and / or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm. The host computer 3230 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 3221, 3222 between the telecommunication network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230 or may go via an optional intermediate network 3220. The intermediate network 3220 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may comprise two or more sub-networks (not shown).

[0094] The communication system of Fig. 9 as a whole enables connectivity between one of the connected UEs 3291, 3292 and the host computer 3230. The connectivity may be described as an over-the-top (OTT) connection 3250. The host computer 3230 and the connected UEs 3291, 3292 are configured to communicate data and / or signaling via the OTT connection 3250, using the access network 3211, the core network 3214, any intermediate network 3220 and possible further infrastructure (not shown) as intermediaries. The OTT connection 3250 may be transparent in the sense that the participating communication devices through which the OTT connection 3250 passes are unaware of routing of uplink and downlink communications. For example, a base station 3212 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 3230 to be forwarded (e.g., handed over) to a connected UE 3291. Similarly, the base station 3212 need not be aware of the future routing of an outgoing uplink communication originating from the UE 3291 towards the host computer 3230.

[0095] Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Fig. 10. In a communication system 3300, a host computer 3310 comprises hardware 3315 including a communication interface 3316 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 3300. The host computer 3310 further comprises processing circuitry 3318, which may have storage and / or processing capabilities. In particular, the processing circuitry 3318 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 3310 further comprises software 3311, which is stored in or accessible by the host computer 3310 and executable by the processing circuitry 3318. The software 3311 includes a host application 3312. The host application 3312 may be operable to provide a service to a remote user, such as a UE 3330 connecting via an OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the remote user, the host application 3312 may provide user data which is transmitted using the OTT connection 3350.

[0096] The communication system 3300 further includes a base station 3320 provided in a telecommunication system and comprising hardware 3325 enabling it to communicate with the host computer 3310 and with the UE 3330. The hardware 3325 may include a communication interface 3326 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3300, as well as a radio interface 3327 for setting up and maintaining at least a wireless connection 3370 with a UE 3330 located in a coverage area (not shown in Fig. 10) served by the base station 3320. The communication interface 3326 may be configured to facilitate a connection 3360 to the host computer 3310. The connection 3360 may be direct or it may pass through a core network (not shown in Fig. 10) of the telecommunication system and / or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 3325 of the base station 3320 further includes processing circuitry 3328, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 3320 further has software 3321 stored internally or accessible via an external connection.

[0097] The communication system 3300 further includes the UE 3330 already referred to. Its hardware 3335 may include a radio interface 3337 configured to set up and maintain a wireless connection 3370 with a base station serving a coverage area in which the UE 3330 is currently located. The hardware 3335 of the UE 3330 further includes processing circuitry 3338, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 3330 further comprises software 3331, which is stored in or accessible by the UE 3330 and executable by the processing circuitry 3338. The software 3331 includes a client application 3332. The client application 3332 may be operable to provide a service to a human or non-human user via the UE 3330, with the support of the host computer 3310. In the host computer 3310, an executing host application 3312 may communicate with the executing client application 3332 via the OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the user, the client application 3332 may receive request data from the host application 3312 and provide user data in response to the request data. The OTT connection 3350 may transfer both the request data and the user data. The client application 3332 may interact with the user to generate the user data that it provides.

[0098] It is noted that the host computer 3310, base station 3320 and UE 3330 illustrated in Fig. 10 may be identical to the host computer 3230, one of the base stations 3212a, 3212b, 3212c and one of the UEs 3291, 3292 of Fig. 9, respectively. This is to say, the inner workings of these entities may be as shown in Fig. 10 and independently, the surrounding network topology may be that of Fig. 9.

[0099] In Fig. 10, the OTT connection 3350 has been drawn abstractly to illustrate the communication between the host computer 3310 and the use equipment 3330 via the base station 3320, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the UE 3330 or from the service provider operating the host computer 3310, or both. While the OTT connection 3350 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

[0100] The wireless connection 3370 between the UE 3330 and the base station 3320 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 3330 using the OTT connection 3350, in which the wireless connection 3370 forms the last segment. More precisely, the teachings of these embodiments may improve the latency and thereby provide benefits such as reduced user waiting time, better responsiveness and / or extended battery lifetime.

[0101] A measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 3350 between the host computer 3310 and UE 3330, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection 3350 may be implemented in the software 3311 of the host computer 3310 or in the software 3331 of the UE 3330, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 3350 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 3311, 3331 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 3350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3320, and it may be unknown or imperceptible to the base station 3320. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer’s 3310 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 3311, 3331 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 3350 while it monitors propagation times, errors etc.

[0102] FIG. 11 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 32 and 33. For simplicity of the present disclosure, only drawing references to Fig. 11 will be included in this section. In a first step 3410 of the method, the host computer provides user data. In an optional substep 3411 of the first step 3410, the host computer provides the user data by executing a host application. In a second step 3420, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 3430, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 3440, the UE executes a client application associated with the host application executed by the host computer.

[0103] FIG. 12 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 32 and 33. For simplicity of the present disclosure, only drawing references to Fig. 12 will be included in this section. In a first step 3510 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 3520, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 3530, the UE receives the user data carried in the transmission.

[0104] FIG. 13 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 32 and 33. For simplicity of the present disclosure, only drawing references to Fig. 13 will be included in this section. In an optional first step 3610 of the method, the UE receives input data provided by the host computer. Additionally or alternatively, in an optional second step 3620, the UE provides user data. In an optional substep 3621 of the second step 3620, the UE provides the user data by executing a client application. In a further optional substep 3611 of the first step 3610, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in an optional third substep 3630, transmission of the user data to the host computer. In a fourth step 3640 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

[0105] FIG. 14 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 32 and 33. For simplicity of the present disclosure, only drawing references to Fig. 14 will be included in this section. In an optional first step 3710 of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In an optional second step 3720, the base station initiates transmission of the received user data to the host computer. In a third step 3730, the host computer receives the user data carried in the transmission initiated by the base station.

[0106] Numbered embodiments

[0107] 1. A base station configured to communicate with a user equipment (UE), the base station comprising a radio interface and processing circuitry configured to estimate an expected signaling condition of the wireless device, determine a customized set of aggregation levels based on the expected signaling condition, and provide a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0108] 5. A communication system including a host computer comprising: processing circuitry configured to provide user data; and a communication interface configured to forward the user data to a cellular network for transmission to a user equipment (UE), wherein the cellular network comprises a base station having a radio interface and processing circuitry, the base station’s processing circuitry configured to estimate an expected signaling condition of the wireless device, determine a customized set of aggregation levels based on the expected signaling condition, and provide a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0109] 6. The communication system of embodiment 5, further including the base station.

[0110] 7. The communication system of embodiment 6, further including the UE, wherein the UE is configured to communicate with the base station.

[0111] 8. The communication system of embodiment 7, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application.

[0112] 11. A method implemented in a base station, comprising: estimating an expected signaling condition of the wireless device, determining a customized set of aggregation levels based on the expected signaling condition, and providing a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0113] 15. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising: at the host computer, providing user data; and at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the base station is configured to estimate an expected signaling condition of the wireless device, determine a customized set of aggregation levels based on the expected signaling condition, and provide a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0114] 16. The method of embodiment 15, further comprising: at the base station, transmitting the user data. 17. The method of embodiment 16, wherein the user data is provided at the host computer by executing a host application, the method further comprising: at the UE, executing a client application associated with the host application.

[0115] 21. A user equipment (UE) configured to communicate with a base station, the UE comprising a radio interface and processing circuitry configured to obtain a customized search space and perform a blind search of the customized search space in order to locate a PDCCH transmission.

[0116] 31. A method implemented in a user equipment (UE), comprising obtaining a customized search space and performing a blind search of the customized search space in order to locate a PDCCH transmission.

[0117] 45. A communication system including a host computer comprising: a communication interface configured to receive user data originating from a transmission from a user equipment (UE) to a base station, wherein the UE comprises a radio interface and processing circuitry, the UE’s processing circuitry configured to obtain a customized search space and perform a blind search of the customized search space in order to locate a PDCCH transmission.

[0118] 46. The communication system of embodiment 45, further including the UE.

[0119] 47. The communication system of embodiment 46, further including the base station, wherein the base station comprises a radio interface configured to communicate with the UE and a communication interface configured to forward to the host computer the user data carried by a transmission from the UE to the base station.

[0120] 48. The communication system of embodiment 46 or 47, wherein: the processing circuitry of the host computer is configured to execute a host application; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data.

[0121] 49. The communication system of embodiment 46 or 47, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing request data; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data in response to the request data.

[0122] 51. A method implemented in a user equipment (UE), comprising obtaining a customized search space and performing a blind search of the customized search space in order to locate a PDCCH transmission.

[0123] 52. The method of embodiment 51, further comprising: providing user data; and forwarding the user data to a host computer via the transmission to the base station.

[0124] 55. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising: at the host computer, receiving user data transmitted to the base station from the UE, wherein the UE is configured to obtain a customized search space and perform a blind search of the customized search space in order to locate a PDCCH transmission.

[0125] 56. The method of embodiment 55, further comprising: at the UE, providing the user data to the base station.

[0126] 57. The method of embodiment 56, further comprising: at the UE, executing a client application, thereby providing the user data to be transmitted; and at the host computer, executing a host application associated with the client application.

[0127] 58. The method of embodiment 56, further comprising: at the UE, executing a client application; and at the UE, receiving input data to the client application, the input data being provided at the host computer by executing a host application associated with the client application, wherein the user data to be transmitted is provided by the client application in response to the input data.

[0128] 61. A base station configured to communicate with a user equipment (UE), the base station comprising a radio interface and processing circuitry configured to estimate an expected signaling condition of the wireless device, determine a customized set of aggregation levels based on the expected signaling condition, and provide a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0129] 65. A communication system including a host computer comprising a communication interface configured to receive user data originating from a transmission from a user equipment (UE) to a base station, wherein the base station comprises a radio interface and processing circuitry, the base station’s processing circuitry configured to estimate an expected signaling condition of the wireless device, determine a customized set of aggregation levels based on the expected signaling condition, and provide a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels.

[0130] 66. The communication system of embodiment 65, further including the base station.

[0131] 67. The communication system of embodiment 66, further including the UE, wherein the UE is configured to communicate with the base station.

[0132] 68. The communication system of embodiment 67, wherein: the processing circuitry of the host computer is configured to execute a host application; the UE is configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

[0133] 71. A method implemented in a base station, comprising estimating an expected signaling condition of the wireless device, determining a customized set of aggregation levels based on the expected signaling condition, and providing a customized search space for use by the wireless device during an upcoming signaling event, the customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels. 75. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising: at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE, wherein the UE is configured to obtain a customized search space indicating the predetermined number of possible locations for the PDCCH distributed across the customized set of aggregation levels and perform a blind search across the customized search space to locate a PDCCH transmission.

[0134] 76. The method of embodiment 75, further comprising: at the base station, receiving the user data from the UE.

[0135] 77. The method of embodiment 76, further comprising: at the base station, initiating a transmission of the received user data to the host computer.

[0136] Modifications and other variants of the described embodiments will come to mind to one skilled in the art having benefit of the teachings presented in the foregoing description and associated drawings. Therefore, it is to be understood that the embodiments are not limited to the specific example embodiments described in this disclosure and that modifications and other variants are intended to be included within the scope of this disclosure. For example, while embodiments of the invention have been described with reference 5G NR, persons skilled in the art will appreciate that the embodiments of the invention can equivalently be applied to other communication standards and techniques where blind searches are performed at different aggregation levels such as 4G LTE, Wi-Fi etc. Furthermore, although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Therefore, a person skilled in the art would recognize numerous variations to the described embodiments that would still fall within the scope of the appended claims. Furthermore, although individual features may be included in different claims (or embodiments), these may possibly advantageously be combined, and the inclusion of different claims (or embodiments) does not imply that a combination of features is not feasible and / or advantageous. In addition, singular references do not exclude a plurality. Finally, reference signs in the claims are provided merely as a clarifying example and should not be construed as limiting the scope of the claims in any way.

Claims

CLAIMS1. A method (400) of determining a Physical Downlink Control Channel, PDCCH, search space set (200) for a wireless device (10) communicatively connected to at least one network device (20), wherein the search space set (200) is configured to indicate a predetermined number (305) of PDCCH candidates (210) distributed across a set of possible aggregation levels (212), the method (400) comprising: estimating (410) an expected signaling condition (315) of the wireless device (10), determining (420) a customized set of aggregation levels (325) based on the expected signaling condition (315), and providing (430) a customized search space set (335) for use by the wireless device (10) during an upcoming signaling event, the customized search space set (335) indicating the predetermined number (305) of PDCCH candidates (210) distributed across the customized set of aggregation levels (325).

2. The method (400) of claim 1, wherein the expected signaling condition (315) comprises estimated received signal data (316) comprising an estimated received signal quality and / or an estimated received signal strength.

3. The method (400) of claim 1 or 2, wherein the expected signaling condition (315) comprises a mobility indicator (317) of the wireless device (10).

4. The method (400) of any one of claims 1 to 3, wherein estimating (410) an expected signaling condition (315) comprises: processing historic signal data (336) from the wireless device (10) to determine the expected signaling condition (315).

5. The method of any one of claims 1 to 4, wherein determining (420) the customized set of aggregation levels (325) comprises:responsive to the expected signaling condition (315) being above a first signaling threshold (301), exclude one or more aggregation levels (215) from the customized set of aggregation levels (325), wherein the one or more excluded aggregation levels (215) are aggregation levels (215) of the set of possible aggregation levels (212) requiring highest bandwidth.

6. The method (400) of any one of claims 1 to 5, wherein determining (420) the customized set of aggregation levels (325) further comprises: responsive to the expected signaling condition (315) being below a second signaling threshold (302), include all aggregation levels (215) from the set of possible aggregation levels (212) in the customized set of aggregation levels (325).

7. The method (400) of any one of claims 1 to 6, further comprising estimating (410) an expected traffic condition (318) of the wireless device (10), wherein the expected traffic condition (318) indicates an expected data rate and an expected burst size of a specific PDU-session (15) of the UE (10); and determining (420) the customized set of aggregation levels (325) further based on the expected traffic condition (318).

8. The method (400) of claim 7, wherein estimating (410) an expected traffic condition (318) further comprises: obtaining a quality of service flow identifier, 5QI (12) of the specific PDU session (15), and estimating (410) the expected traffic condition (318) based on the 5QI (12).

9. The method (400) of claim 7 or 8, wherein estimating (410) an expected traffic condition (318) further comprises: obtaining a single network slice selection assistance information, S-NSSAI,estimating (410) the expected traffic condition (318) based on the S-NSSAI (13).

10. The method (400) of any one of claims 7 to 9, wherein determining (420) the customized set of aggregation levels (325) further comprises: responsive to the expected signaling condition (315) being above the first signaling threshold (301), and the expected traffic conditions (318) indicating a data rate being above a data rate threshold and the expected traffic conditions (318) indicating a burst size being below a burst size threshold, exclude one or more aggregation levels (215) from the customized set of aggregation levels (325), wherein the one or more excluded aggregation levels (215) are aggregation levels (215) of the set of possible aggregation levels (212) requiring highest bandwidth.

11. The method (400) of any one of claims 7 to 10, wherein determining (420) the customized set of aggregation levels (325) is further comprises: responsive to the expected traffic conditions (318) failing to indicate a data rate being above the data rate threshold and a burst size being below the burst size threshold, include all aggregation levels (315) from the set of possible aggregation levels (212) in the customized set of aggregation levels (325).

12. A processing circuitry (800), configured to cause execution of the method (400) of any one of claims 1 to 11.

13. A base station, BS, (20) comprising the processing circuitry of claim 12.

14. A communications network (1) comprising a BS (20) configured to communicate with one or more wireless devices (10) and cause execution of the method (400) of any one of claims 1 to 11.

15. A computer program product (500) comprising a non-transitory computer readable medium (600), having thereon a computer program (700) comprising program instructions (710), the computer program (700) being loadable into processing circuitry (800) and configured to cause execution of the method (400) according to any of claims 1 through 11 when the computer program (600) is run by the data processing unit (800).

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