Method and apparatus for configuring physical downlink control channel search space to user equipment

Abstract

Embodiments described herein relate to methods and apparatus for configuring a physical downlink control channel, PDCCH, search space to a user equipment, UE. A method performed by a network node includes sending a reduced aggregation level, AL, search space configuration to the UE, where the reduced AL search space configuration includes only a set of control channel element, CCE, candidates in an AL that is lower than a maximum aggregation level available in a communication network.

Description

Technical Field

[0001] The embodiments described herein relate to methods and apparatus for configuring the physical downlink control channel (PDCCH) search space for a user equipment (UE). Background Technology

[0002] 5G New Radio (NR) Forward Compatibility Design Concept

[0003] A major difference between 5G NR and 4G LTE is that 5G NR has a much higher level of ambition when it comes to backward compatibility than 4G LTE. This is manifested in the fact that individual user equipment (UE) can be configured to a much greater extent in NR compared to LTE.

[0004] The basic principle is that adding specifications in the future will be much easier because networks should be able to find ways to configure older UEs in a way that does not conflict with newer UEs that have newer capabilities. In this way, standardization work does not need to predict every possible future addition to the standard.

[0005] This also means that, during the standardization process, all possible ways to utilize the current standard are unknown. A good analogy here is programming languages: specifications in terms of syntax and semantics do not automatically mean that all useful programs that can be written in the programming language are known when the language is created.

[0006] NR Physical Downlink Control Channel (PDCCH)

[0007] The PDCCH is where the base station (e.g., gNB) sends downlink control information (DCI) to the UE. The main types of DCI in today's 5G networks include downlink assignment and uplink permission, both of which notify the UE of data transmission on shared data channels (Physical Downlink Shared Channel PDSCH and Physical Uplink Shared Channel PUSCH, respectively).

[0008] Downlink assignment notifies the UE that the gNB has transmitted data and requests the UE to attempt to receive data, while uplink permission requests the UE to transmit. In both cases, DCI is a message with transmission parameters such as transmission bandwidth and location, as well as modulation and coding scheme (MCS).

[0009] The above naturally raises the question: how does the UE know that there is a DCI to receive? The answer is simple: it doesn't know. The UE must attempt to decode all possible DCIs in all possible transmission formats at every possible transmission opportunity. This type of scheme is often called blind decoding.

[0010] Since the computational cost of attempting to decode possible DCI transmissions (which translates to both chip cost and battery consumption) is quite high, it may be considered beneficial in standardization efforts to keep the number of possible transmissions that the UE must attempt to decode relatively small.

[0011] One way the standard keeps the number of possible transmissions that the UE must attempt to decode relatively small is by limiting the number of different DCI message sizes. This is a very natural limitation because the control data required for notification transmissions is the same for every transmission.

[0012] A second way the standard keeps the number of possible transmissions that a UE must attempt to decode small is by limiting the possible allowed modulation and coding schemes. As with data transmission, it may be considered important to choose an appropriate robustness for the DCI based on channel quality. If the network uses the most robust format for all UEs, capacity will be very poor, and always using the least robust format may not be beneficial for coverage reasons. The standard currently only allows QPSK modulation and does not allow explicit selection of the code rate. Instead, robustness varies by the amount of spectrum resources used, and the code rate is then derived solely from the message size and the amount of spectrum resources.

[0013] A third way the standard keeps the number of possible transmissions that the UE must attempt to decode relatively small is by limiting the possible number of spectrum resources that can be used. The basic spectrum resource unit used for PDCCH is called a Control Channel Element (CCE), which comprises resource elements used in six Physical Resource Blocks (PRBs) over the time of one OFDM symbol, with one PRB having 12 OFDM subcarriers in frequency. The number of CCEs used for PDCCH transmissions is called the Aggregation Level (AL), and the standard limits the possibilities to 1 CCE, 2 CCEs, 4 CCEs, 8 CCEs, and 16 CCEs, respectively AL 1, AL 2, AL 4, etc. Since DCI messages typically have the same size order (usually less than 100 bits), this limitation is also quite straightforward.

[0014] The aforementioned set of limitations still results in a very large number of combinations that the UE will have to decode, especially in high bandwidth environments. To further reduce the set of combinations that the UE must attempt to receive, the standard stipulates that the UE should only listen to a subset of all possible combinations. The set of possible combinations on which the UE attempts to receive DCI messages is called the "search space set" and includes a set of CCEs for each AL, where each set of CCEs for a particular AL is called a candidate.

[0015] The search space set is determined based on the time slot number and UE identifier using a pseudo-random number generation algorithm (defined in Section 10.1 of 5G; NR; Physical Layer Procedures for Control (3GPP TS 38.213 Release 17.7.0)). This pseudo-random number generation algorithm is designed to prevent UEs from having a large amount of search space overlap systematically. The number of candidates in the search space and what kind of CCEs might be part of the search space set are determined by the gNB and signaled using the Radio Resource Control (RRC) protocol.

[0016] Figure 1 The illustration shows an example of two search spaces for UE 20955 in two different time slots. It will be understood that a time slot is the basic unit of time within a frame and is used to transmit data and control information. In 5G NR, time slots may have different lengths and configurations. The time slot structure in 5G NR is more flexible than in previous generations, allowing for the use of different time slot lengths and configurations within the same frame. This flexibility supports diverse use cases and allows for efficient spectrum utilization.

[0017] Figure 2 The illustration shows an example of two search space sets for UE 4402 in two different time slots.

[0018] exist Figure 1 and Figure 2 In the diagram, candidates are represented as a continuous set of boxes (or a single box for AL 1). The x-axis shows the CCE index, while the y-axis shows the AL. For example, if the network wants to send DCI to UE 4402 using AL4, it might need to use CCE 20-23 or 40-43 in slot 0 and CCE 8-11 or 32-35 in slot 1. For visibility purposes, Figure 1 and Figure 2 Each AL has a separate row because candidates for different ALs often overlap.

[0019] There are two main constraints for configuring the search space that the network must adhere to so as not to exceed the UE's decoding capability. The first constraint is that the total number of candidates in all search space sets must not exceed a certain number during a single time slot. This is referred to in this paper as the number of blind decoding attempts.

[0020] The second constraint is that the total number of non-overlapping CCEs must not exceed a certain number. Here, "non-overlapping" simply means that regardless of how many PDCCH candidates use the CCE index, that index is counted only once. For example, looking at UE 4402 slot 1 in the diagram, CCE index 8 is used by candidates AL16, AL8, and AL4, but it is only counted as one non-overlapping CCE.

[0021] The exact number of parameters used for the first and second constraints depends on the parameter set (numerology) and is specified in Tables 10.1.-2 and 10.1.-3 of 3GPPTS 38.213 version 17.7.0 version 17.

[0022] The NR standard allows for multiple search space configurations within the same time slot, where search space configurations include (among many other things):

[0023] 1. Number of candidates generated for each aggregation level

[0024] 2. Candidate frequency domain resources can be generated within it.

[0025] 3. Duration of the search space, expressed as a symbolic number.

[0026] 4. Starting symbol of the search space

[0027] 5. The UE can anticipate receiving DCI messages in the search space.

[0028] The SearchSpace and ControlResourceSet information elements defined in the 5G NR; Radio Resource Control (RRC); Protocol Specification (3GPP TS 38.331 Release 17.6.0 Release 17) are used to transmit the above information to the UE.

[0029] This flexibility allows the network to configure additional search space for the UE to meet capacity requirements, for example, by configuring the UE to listen to the PDCCH in the second symbol instead of the first symbol, or listening to the PDCCH in the second symbol in addition to the first symbol. This allows the network to balance the demand for PDCCH with the data rate of PDSCH (because the symbols used for PDCCH are taken from PDSCH).

[0030] However, the above constraints may need to be satisfied for the sum of all search space sets in a single time slot.

[0031] Search space type

[0032] It is possible to configure the search space as a so-called common search space (CSS). The common search space does not use the aforementioned (pseudo)randomization algorithm, ensuring that candidates are always in the same position in each slot regardless of the UE identifier. Another type of search space is called the UE-specific search space (USS).

[0033] Compared to USS, CSS is less attractive from a capacity perspective because the strength of broadcast messages is typically very low compared to the strength of UE-specific messages. However, the constraint regarding the number of blind decoding attempts and non-overlapping CCEs is counted over all search spaces configured for the UE, including the common search space.

[0034] When connecting to a cell, it is assumed that the CSS is sent in the system information (for obvious reasons, it does not need to be detected by the PDCCH). Summary of the Invention

[0035] There are some challenges at present.

[0036] Since most traffic consists of small packets, the PDCCH is often the capacity bottleneck in NR systems. This means that a typical high-load cell has a very large number of users, most of whom need to send very small amounts of data.

[0037] Adding more symbols to the PDCCH (by configuring more search space) is a natural way to handle the typical high-load cells described above. However, under high bandwidth, non-overlapping CCE constraints become severe because they limit the number of candidates each UE can listen to. (Comparison) Figure 3a and Figure 3b This is an indication that...

[0038] Figure 3a The illustration shows an example of a PDCCH search space set using a configuration that has a search space only in symbol 0. In this case, the total number of non-overlapping CCEs is 31 (other slot numbers and / or UE IDs will result in a different number).

[0039] Figure 3b The illustration shows an example of a PDCCH search space set using a configuration with a search space in symbol 0 and another search space in symbol 1. In this case, the total number of non-overlapping CCEs is 31 (other slot numbers and / or UE IDs will result in a different number).

[0040] Although both have the same number of non-overlapping CCEs, but with Figure 3a compared to, Figure 3b The configuration in this configuration has fewer candidates overall.

[0041] One known way to mitigate non-overlapping constraints is to utilize standard capabilities to configure each UE individually.

[0042] This can be used to give UEs in poor radio conditions higher AL (e.g., AL16 and / or AL8) candidates and fewer (or zero) lower AL (e.g., AL1 and / or AL2) candidates, and vice versa for UEs in good radio conditions. The disadvantage is that it requires RRC signaling to change the search space configuration when radio conditions change, which takes a long time and carries an increased risk of losing connectivity to the UE.

[0043] Another way to alleviate non-overlapping constraints is to have different configurations for different UEs, such that some UEs have (more) candidates in the first symbol, some UEs have (more) candidates in the second symbol, and so on.

[0044] Figure 4a The illustration shows an example of UE 20955 with two search space configurations, where the search space configuration in symbol 0 has more candidates than the search space configuration in symbol 1. Figure 4b The illustration shows an example of UE 4402 with two search space configurations, where the search space configuration in symbol 0 has fewer candidates than the search space configuration in symbol 1.

[0045] The drawback of this approach is that a UE with its PDCCH in symbol n cannot use symbols preceding n for its PDSCH (and can only use symbol n for PDSCH if the PDSCH allocation does not overlap with any other UE's PDCCH allocation). As UEs come and go, there will inevitably be UEs with large amounts of data, eventually causing their search space to be configured so that PDCCH can only be allocated in symbols >0. Therefore, system resources are wasted whenever these users are scheduled, as symbols preceding the user's PDCCH cannot be (effectively) used for anything. This again requires the network to reconfigure the UE via RRC, and effectively calculating when and how to reconfigure is not an easy problem to solve in the design.

[0046] A similar idea for handling non-overlapping constraints is to use a smaller frequency segment for each UE and configure different UEs to listen to different segments. For example, if the number of CCEs in the CCE pool is limited to 16, then the maximum number of non-overlapping CCEs in a single symbol will naturally never exceed 16. This allows for more search space in other symbols without reaching the non-overlapping CCE limit. This has a slightly similar drawback to the one described above, as the system will eventually be in a state where the frequency segments listened to by active UEs are unbalanced. Solving this problem requires RRC reconfiguration and the important functionality of determining how and when to reconfigure.

[0047] Certain aspects of this disclosure and its embodiments may provide solutions to these or other challenges.

[0048] In particular, the embodiments described herein improve PDCCH capacity. Typically, PDCCH is affected when 1000 UEs have data to transmit, thus requiring the scheduling of a large number of UEs, which the current search space configuration lacks the capacity to schedule all UEs without encountering congestion issues. UEs effectively compete on the same CCE.

[0049] Therefore, according to some embodiments, a method is provided for configuring a Physical Downlink Control Channel (PDCCH) search space for a User Equipment (UE) by a network node in a communication network. The method includes sending a reduced aggregation level (AL) search space configuration to the UE, wherein the reduced AL search space configuration includes only a candidate set of Control Channel Elements (CCEs) in ALs lower than the maximum aggregation level available in the communication network.

[0050] A method for configuring a Physical Downlink Control Channel (PDCCH) search space, performed by a user equipment in a communication network. The method includes receiving a reduced aggregation level (AL) search space configuration from a network node, wherein the reduced AL search space configuration includes only a candidate set of Control Channel Elements (CCEs) in ALs lower than the maximum available AL in the communication network.

[0051] A network node in a communication network is configured to configure a Physical Downlink Control Channel (PDCCH) search space for a User Equipment (UE). The network node includes processing circuitry and a memory containing instructions executable by the processing circuitry, thereby enabling the network node to: send a reduced aggregation level (AL) search space configuration to the UE, wherein the reduced AL search space configuration includes only a candidate set of Control Channel Elements (CCEs) in ALs lower than the maximum aggregation level available in the communication network.

[0052] A user equipment (UE) in a communication network is used to configure a physical downlink control channel (PDCCH) search space. The UE includes processing circuitry and a memory containing instructions executable by the processing circuitry, thereby enabling the UE to: receive a reduced aggregation level (AL) search space configuration from a network node, wherein the reduced AL search space configuration includes only a candidate set of control channel elements (CCEs) in ALs lower than the maximum available AL in the communication network.

[0053] A computer program comprising instructions that, when executed on at least one processor, cause the at least one processor to perform any of the methods described above.

[0054] According to some embodiments, a carrier comprising the computer program described above is provided, wherein the carrier includes one of electronic signals, optical signals, radio signals, or computer-readable storage media.

[0055] According to some embodiments, a computer-readable medium including instructions is provided that, when executed on at least one processor, cause the at least one processor to perform any of the methods described above.

[0056] A computer program product comprising a non-transitory computer-readable medium having the computer program as described above stored thereon.

[0057] Certain embodiments may provide one or more of the following technical advantages.

[0058] When discussing capacity, specifically the number of UEs that can be scheduled simultaneously, the embodiments described herein offer a significant advantage over existing technologies. It effectively alleviates the bottleneck of the PDCCH as a system capacity constraint, and thereby improves content time and throughput for end users in cells with medium to high loads without sacrificing coverage.

[0059] For example, the fact that a single AL4 PDCCH candidate can fulfill the roles of AL4, AL8, and AL16 without consuming additional non-overlapping CCEs and blind decoding attempts, combined with its less sensitivity to fragmentation issues (described below), makes this method significantly more efficient than existing techniques, as will be discussed later. Figure 12 and Figure 13 As shown in the diagram. Attached Figure Description

[0060] To better understand the embodiments of this disclosure and to show how they can be implemented, reference will now be made to the accompanying drawings by way of example only, in which:

[0061] Figure 1 The illustration shows examples of two search spaces for UE 20955 in two different time slots;

[0062] Figure 2 The illustration shows an example of two search space sets for UE 4402 in two different time slots;

[0063] Figure 3a The illustration shows an example of a PDCCH search space set using a configuration that has a search space only in symbol 0;

[0064] Figure 3b The illustration shows an example of a PDCCH search space set configured to use a search space in symbol 0 and another search space in symbol 1;

[0065] Figure 4a The illustration shows an example where UE 20955 has two search space configurations, where the search space configuration in symbol 0 has more candidates than the search space configuration in symbol 1;

[0066] Figure 4b The illustration shows an example where UE 4402 has two search space configurations, where the search space configuration in symbol 0 has fewer candidates than the search space configuration in symbol 1;

[0067] Figure 5 The diagram illustrates an example process for configuring the search space for offline verification against all possible UE identifiers;

[0068] Figure 6 The diagram illustrates the signaling diagram for Radio Resource Control (RRC) reconfiguration;

[0069] Figure 7 This is a flowchart illustrating a method according to some embodiments;

[0070] Figure 8 The illustration shows an example of a 2-symbol reduced AL search space configuration that satisfies both the maximum blind decoding attempt and non-overlapping CCE constraints in parameter set 1.

[0071] Figure 9 The illustration shows an example implementation of step 704;

[0072] Figure 10 The illustration shows an example implementation of step 704;

[0073] Figure 11 This is a flowchart illustrating a method according to some embodiments;

[0074] Figure 12 The figure shows the results from the simulation, illustrating the relationship between the number of time slots (y-axis) that users were prevented from scheduling due to the lack of PDCCH and the load (x-axis).

[0075] Figure 13 The figure shows the results from the simulation, illustrating the relationship between end-user packet delay (y-axis) and load (x-axis);

[0076] Figure 14 Examples of communication systems according to some embodiments are shown;

[0077] Figure 15 A UE is shown according to some embodiments;

[0078] Figure 16 A network node is shown according to some embodiments. Detailed Implementation

[0079] From a capacity perspective, it will be understood that the goal of search space configuration is to accommodate as many PDCCH candidates as possible in the search space without exceeding the constraints on the number of blind decodes and non-overlapping CCEs. The number of blind decodes is straightforward, as it is simply a matter of counting the total number of candidates. For the number of non-overlapping CCEs, there is no known closed-form expression. Instead, the only way to determine whether a potential search space configuration satisfies the non-overlapping CCE constraint is to try all slots in the frame for the selected UE identifier (10 for parameter set 0, 20 for parameter set 1, and so on). A very reasonable simplification is to validate the search space configuration offline for all possible UE identifiers (approximately 2^16 possibilities in NR) and apply that configuration to all UEs. An example of this process is... Figure 5 As shown in the diagram, being able to check whether the non-overlapping CCE constraint is satisfied is insufficient to find a good configuration that helps alleviate the capacity problem.

[0080] Some embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0081] The embodiments described herein can be performed in two main steps. The first step is to configure the PDCCH search space. For this purpose, the configuration can be, for example, in... Figure 6 The RRC reconfiguration message illustrated in step 601 is sent to the UE, and is typically performed when the UE first attaches to the cell. The UE can then use... Figure 6 The RRC reconfiguration message is responded to by the RRC reconfiguration complete message illustrated in step 602.

[0082] The second step is to select which PDCCH candidate to use and what power level to use for the transmission represented as the CCE allocation. This step can be performed for each individual PDCCH transmission, so it naturally occurs at a much higher frequency compared to search space configuration.

[0083] from Figure 1 As shown in Figure 4, higher aggregation levels are more difficult to accommodate within the search space set than lower aggregation levels because they are more prone to congestion. For example, when viewing the graph, smaller aggregation levels tend to fragment CCE resources, making it impossible for larger aggregation levels to accommodate them, even though there are still many CCEs available in total. This is referred to as the "fragmentation problem" in this paper.

[0084] Traditional techniques that can be considered solutions to this type of problem (such as Boolean satisfiability problem techniques or mixed-integer programming) are not feasible in practice. CCE allocation must be performed in every time slot because the search space is randomized for each time slot, and the simple fact that which users have data and how important that data is changes from time slot to time. Even simple custom heuristics, such as identifying high-AL UEs in advance and avoiding their PDCCH candidates where possible, are hampered by the fact that the number of UEs and PDCCH candidates that the network can handle in a time slot is typically very limited.

[0085] Therefore, the embodiments described herein utilize the inventive understanding that high AL is the primary culprit for both fragmentation problems and non-overlapping CCEs.

[0086] Therefore, the embodiments described herein use a search space configuration with only low ALs (e.g., only AL1, AL2, and AL4), allowing the search space to become dense without exceeding the constraint of the number of non-overlapping CCEs. The loss of coverage can then be compensated for using increased transmit power. For example, instead of AL8, the embodiments described herein can use AL4 and double the transmit power. Similarly, instead of AL16, the embodiments described herein can use AL4 and quadruple the transmit power.

[0087] Figure 7 The illustration depicts a method performed by a network node in a communication network according to a specific embodiment. This method can be used to configure the Physical Downlink Control Channel (PDCCH) search space for a User Equipment (UE). Figure 7 The method can be used by network nodes (e.g., see later for details). Figure 14 and Figure 16 The method is performed by network node 1410 or network node 1600 as described. In some examples, the method may begin at step 701 by sending a reduced aggregation level AL search space configuration to the UE, wherein the reduced AL search space configuration includes only a candidate set of control channel elements (CCEs) in ALs that are lower than the maximum aggregation level available in the communication network.

[0088] In this paper, the term reduced to aggregation level AL search space configuration can be used to refer to any search space configuration for which at least the maximum available aggregation level in the communication network has not yet been used to form a candidate set of CCEs. The maximum available aggregation level in the communication network can be determined, derived, or set by the criteria by which network nodes operate.

[0089] For example, a reduced AL search space configuration may include only the candidate set of control channel elements in AL 1 to AL 4 or AL 1 to AL 8 (e.g., for NR).

[0090] Step 701 may include configuring the reduced AL search space as a Radio Resource Control (RRC) message (e.g., as...). Figure 6 A portion of the RRC reconfiguration message 601 shown in the figure is sent.

[0091] Once the network node has configured the reduced AL search space configuration for the UE, it can apply different transmit powers when transmitting PDCCH transmissions using one of the CCE candidate sets to achieve different levels of robustness. An example of how to perform this operation is provided later. Figure 9 and Figure 10 As stated above.

[0092] Figure 8 The illustration shows an example of a 2-symbol reduced AL search space configuration that satisfies both the maximum blind decoding attempt and non-overlapping CCE constraints, where the subcarrier spacing is 30 kHz. Specifically, Figure 8 The diagram illustrates a PDCCH search space set using a configuration with a search space in symbol 0 and another search space in symbol 1, where AL8 and AL16 are replaced by lower AL candidates.

[0093] However, it will be understood that when different transmit powers are applied, the power increase may cause harmful interference to neighboring cells. Therefore, in some examples, Figure 7 The method includes step 702. Step 702 enables network nodes to apply power boosts only when power boosts are truly needed (to address PDCCH congestion issues).

[0094] Step 702 may include determining whether the PDCCH blocking level in the cell serving the first UE satisfies a first threshold condition associated with a first threshold blocking level.

[0095] Then, step 701 can be performed in response to determining that the PDCCH blocking level in the cell serving the first UE meets the first threshold condition associated with the first threshold blocking level.

[0096] To determine the PDCCH blocking level, cell-level counters PDCCH-blocking-PDSCH-occasions and PDCCH-blocking-PUSCH-occasions may be considered for evaluation. It is possible that these cell-level counters are collected at different time granularities. Alternatively, cell load (in terms of PRB utilization and the number of RRC connected users) may be considered in place of PDCCH blocking, or cell load may be considered in addition to PDCCH blocking, to evaluate the PDCCH blocking level.

[0097] In some examples, PDCCH blocking can be considered to have occurred when the following condition is met after resource allocation is performed on a time slot:

[0098] 1. At least one UE with data in the uplink or downlink did not receive PDCCH resources.

[0099] 2. There are one or more unused shared channels (PRBs) of the type required by the UE (i.e., PDSCH for downlink data or PUSCH for uplink data).

[0100] The ratio of time slots in which PDCCH blocking occurs can be used as the PDCCH blocking level for a cell.

[0101] in other words, Figure 7 The method may also include determining the PDCCH blocking level based on one or more of the following: the ratio of time periods (e.g., time slots) in the cell where PDCCH blocking occurs in multiple time periods (e.g., 100-10k time slots); and the average number of unused shared channel PRBs of the type required by the UE in multiple time periods in the cell.

[0102] In some examples, PDCCH blocking can be considered to have occurred when a shared channel of the type required by the UE exists, or when another UE with lower priority obtains a shared channel of the type required by the UE (i.e., PDSCH for downlink data or PUSCH for uplink data). When applying this definition of PDCCH blocking, the shared channel PRB assigned to the lower-priority UE can also be counted in the blocking level (because if the higher-priority UE is not prevented from obtaining the PDCCH resources, these resources could have been assigned to the higher-priority UE).

[0103] In some examples, the first threshold condition in step 702 includes a condition that the PDCCH blocking level is greater than or equal to the first threshold level.

[0104] If it is determined in step 702 that the PDCCH blocking level does not meet the first threshold condition, the method may proceed to step 703, which includes sending a normal search space configuration to the UE. The normal search space configuration may be a search space configuration utilizing all available AL levels in the communication network. In this example, when sending a PDCCH transmission to the UE using the CCE candidate set in the normal search space configuration, the network node may not apply power boost.

[0105] In some examples, further granularity can be applied to define the ALs included in the reduced AL search space configuration.

[0106] For example, in some examples, step 701 may include step 701a. Step 701a includes determining whether the PDCCH blocking level meets a second threshold condition. The second threshold condition may be that the PDCCH blocking level is less than a second threshold level.

[0107] If the PDCCH blocking level satisfies the first threshold condition associated with the first threshold blocking level and the second threshold condition associated with the second threshold blocking level, the method proceeds to step 701b, in which the reduced AL search space configuration (sent in step 701) includes only the candidate set of control channel elements (CCEs) in ALs lower than at least the highest Y aggregation levels available in the communication network, where Y is greater than or equal to 1. For example, Y can be equal to 1. For example, if a network node deems AL 16 suitable, the network node can select AL 8 as a candidate and can utilize a 3 dB power boost instead of AL 16.

[0108] If the PDCCH blocking level satisfies the first threshold condition associated with the first threshold blocking level but not the second threshold condition associated with the second threshold blocking level, the method proceeds to step 701c, in which the reduced AL search space configuration (sent in step 701) includes only a candidate set of control channel elements (CCEs) in ALs with aggregation levels lower than at least Z (where Z>Y) available in the communication network. For example, Z can be equal to 2. In this example, network nodes can use CCE-AL 4 with a 6 dB power boost and CCE-AL 4 with a 3 dB power boost, instead of CCE-AL 16 and CCE-AL 8.

[0109] It will be understood that any number of threshold conditions can be introduced to control the configuration of the reduced AL search space.

[0110] For example, the third threshold condition could be whether the PDCCH blocking level is greater than a third threshold level. If this condition is met, the reduced AL search space configuration could include only the candidate set of CCEs in ALs that are lower than at least the highest W (where W > Z) ALs available in the communication network. For example, W could be equal to 3. In this example, network nodes could use CCEs in AL 2 with a 6 dB power boost, CCEs in AL 2 with a 3 dB power boost, and CCEs in AL 4 with a 6 dB power boost, instead of CCE-AL 8, CCE-AL 4, and CCE-AL 16.

[0111] In some embodiments, Figure 7 The method may then further include step 704, in which the network node sends a PDCCH transmission to the UE using one of the CCE candidate sets in the reduced aggregation level AL search space configuration. In some examples, the transmission of the PDCCH to the UE is performed using, for example, some power boost to accommodate the reduced AL search space configuration.

[0112] CCE allocation is performed for each individual PDCCH transmission to be executed by the network. CCE allocation can be broken down into the following two steps:

[0113] 1. Determine which AL and power are needed so that the transmission has an acceptable probability of being successfully decoded in the UE.

[0114] 2. In the search space set of individual UEs, which PDCCH candidates should be allocated to minimize the fragmentation problem?

[0115] For example, step 704 can be referenced. Figure 9 The execution is described.

[0116] In step 901, the method includes estimating the downlink SINR associated with the UE, i.e., SINR_est. The downlink SINR estimate can be made based on CSI reports, HARQ feedback, and uplink reference signals (assuming reciprocity). Therefore, Figure 9 The method may also include determining the downlink SINR based on one or more of the following: channel state information reports from the UE, HARQ feedback from the UE, and uplink reference signals received from the UE.

[0117] In step 902, the method includes mapping SINR_est to a first AL, wherein the first AL is included in a reduced AL search space configuration. The mapping can be derived by using simulation results or laboratory test results to map SINR to the lowest AL with an acceptable error probability.

[0118] In step 903, the method includes determining a first transmit power based on a nominal transmit power assumed for SINR_est and a minimum downlink SINR, i.e., SINR_AL_s, for which the first AL has a minimum threshold probability of successful reception at the UE. For example, the first transmit power can be determined as 1 or the maximum value of SINR_AL_s / SINR_est multiplied by the nominal transmit power.

[0119] In step 904, the method then includes transmitting a PDCCH transmission using a first transmit power and a first set of CCE candidates in the first AL.

[0120] In another example, step 704 can be as referenced. Figure 10 The execution is described.

[0121] In step 1001, the method includes determining which PDCCH transmission to the UE should utilize the first AL based on a mapping that maps the first AL to the downlink channel quality associated with the UE, wherein the first AL is not included in the reduced AL search space configuration. The mapping can be derived by mapping the downlink channel quality to the lowest AL with an acceptable error probability using simulation results or laboratory test results. The downlink channel quality can be estimated based on CSI reports, HARQ feedback, and uplink reference signals (where reciprocity can be assumed). Therefore, Figure 10 The method may also include determining downlink channel quality based on one or more of the following: channel state information reports from the UE, HARQ feedback from the UE, and uplink reference signals received from the UE.

[0122] Step 1002 includes, in response to step 1001, transmitting PDCCH at a second transmit power higher than the first transmit power, utilizing a second AL included in the reduced AL search space configuration.

[0123] In some examples, the first AL includes AL N, and the second AL includes AL N / M, where N is an integer and M is another integer, and where the first transmit power includes XW (X watts) and the second transmit power includes M*XW (M*X watts).

[0124] For example, if the first transmit power (AL) is AL 8, then the second AL can be AL 4, and the second transmit power can be increased by a factor of 2 compared to the first transmit power. If the first AL is AL 16, then the second AL can be AL 4, and the second transmit power can be increased by a factor of 4 compared to the first transmit power. Here, the first transmit power can be the nominal power assumed when performing downlink channel quality estimation / measurement.

[0125] Regarding step 2 of the CCE allocation above, it is worth noting that since high AL is replaced by higher transmit power, simple schemes such as greedy heuristics can work better with the embodiments described herein, because transmit power can be freely allocated among users.

[0126] Figure 11 A method according to a particular embodiment is described. Figure 11 The method can be performed by the UE or a radio device (e.g., referred to separately later). Figure 14 and Figure 15 This method is performed by UE 1412 or UE 1500. It can be executed to enable the configuration of the Physical Downlink Control Channel (PDCCH) search space. The method begins at step 1102, receiving a reduced aggregation level (AL) search space configuration from the network node, wherein the reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs lower than the maximum available AL in the communication network. For example, the reduced AL search space configuration may include only the candidate set of control channel elements in ALs 1 through AL 4, or only in ALs 1 through AL 8. The reduced AL search space configuration may be sent as part of a Radio Resource Control (RRC) message.

[0127] Experimental results

[0128] To determine whether the present invention offers any significant advantages over existing technologies, system simulations were performed in a dynamic system simulator. The service model used was fitted based on packet-level data from high-load sites in a real network. A 100 MHz TDD using parameter set 1 was employed.

[0129] The following options are simulated:

[0130] ●1 symbol

[0131] – Symbol 1 SS:{5,4,3,2,2}

[0132] ●2 symbols

[0133] – Symbol 1 SS:{4,2,1,1,1}

[0134] – Symbol 2 SS:{4,1,1,0,0}

[0135] ●2 symbol pb (power boost)

[0136] – Symbol 1 SS:{4,2,3,0,0}

[0137] – Symbol 2 SS:{2,2,3,0,0}

[0138] – Aggregation level 4 can use 1x, 2x, or 4x of the nominal power (all other aggregation levels can only use 1x).

[0139] ●2 symbol pc (power control)

[0140] – Symbol 1 SS:{4,2,3,0,0}

[0141] – Symbol 2 SS:{2,2,3,0,0}

[0142] – Polymerization level 1 can use 0.25x, 0.5x, or 1x nominal power, while polymerization levels 2 and 4 have a set of fine-grained allowable power levels.

[0143] ●2 Symbol Magic

[0144] – Symbol 1 SS:{4,2,1,1,1}

[0145] – Symbol 2 SS:{45,23,12,6,3}

[0146] The label SS: {A, B, C, D, E} means that A AL1 candidates, B AL2 candidates, and so on are provided in the search space.

[0147] The options referred to as "1 symbol" and "2 symbol" are from the prior art. The options referred to as "2 symbol pb" and "2 symbol pc" represent different embodiments of the present invention. The option "2 symbol magic" represents an impractical upper bound on which the search space constraints are removed.

[0148] Figure 12 The results from the simulation are illustrated, showing the relationship between the number of time slots (y-axis) that prevent at least one user from being scheduled due to the lack of PDCCH and the load (x-axis).

[0149] Both the mean (average) and the 95th percentile (p95) are shown.

[0150] Figure 13 The results from the simulation are illustrated, showing the relationship between end-user packet delay (y-axis) and load (x-axis). Both the mean (average) and the 95th percentile (p95) are shown.

[0151] Figure 12 and Figure 13 As illustrated, adding an extra symbol in the prior art has a net negative effect because the search space becomes sparser due to the non-overlapping CCE constraint. On the other hand, the embodiments described herein demonstrate performance that is almost as good as the theoretical upper bound (where the constraints for blind decoding attempts and non-overlapping CCEs are removed).

[0152] Figure 14 An example of a communication system 1400 according to some embodiments is shown.

[0153] In this example, communication system 1400 includes a telecommunications network 1402 and a core network 1406. Telecommunications network 1402 includes an access network 1404, such as a radio access network (RAN), and core network 1406 includes one or more core network nodes 1408. Access network 1404 includes one or more access network nodes, such as network nodes 1410a and 1410b (one or more of which may generally be referred to as network node 1410), or any other similar 3GPP access node or non-3GPP access point. Furthermore, as those skilled in the art will understand, network nodes are not necessarily limited to implementations in which the radio and baseband portions are supplied and integrated by a single vendor. Therefore, it will be understood that network nodes include decomposed implementations or portions thereof. For example, in some embodiments, telecommunications network 1402 includes one or more Open RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunications network 1402 that supports ORAN specifications (e.g., specifications published by the O-RAN Alliance or any similar organization) and can operate alone or with other nodes to perform one or more functions of any node in the telecommunications network 1402 (including one or more network nodes 1410 and / or core network node 1408).

[0154] Examples of ORAN network nodes include Open Radio Units (O-RUs), Open Distributed Units (O-DUs), Open Central Units (O-CUs) including an O-CU control plane (O-CU-CP) or an O-CU user plane (O-CU-UP), RAN Intelligent Controllers (near real-time or non-real-time) hosting software or software plug-ins (such as near real-time control applications (e.g., xApp) or non-real-time control applications (e.g., rApp)), or any combination thereof (the adjective "open" indicates support for the ORAN specification). Network nodes can support the specification by, for example, supporting interfaces defined by the ORAN specification (such as A1, F1, W1, E1, E2, X2, Xn interfaces, Open Fronthaul User Plane Interface, or Open Fronthaul Management Plane Interface). Furthermore, ORAN access nodes can be logical nodes within physical nodes. Additionally, ORAN network nodes can be implemented in a virtualized environment (described further below), in which one or more network functions are virtualized. For example, the virtualized environment may include an O-Cloud computing platform orchestrated by a service management and orchestration framework via an O-2 interface defined by the O-RAN Consortium or similar technologies. Network node 1410 facilitates direct or indirect connections of user equipment (UE), such as connecting UE 1412a, 1412b, 1412c and 1412d (one or more of which may generally be referred to as UE 1412) to core network 1406 via one or more wireless connections.

[0155] Examples of wireless communication via wireless connection include sending and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for transmitting information without the use of wires, cables, or other conductors. Furthermore, in various embodiments, communication system 1400 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that can facilitate or participate in the communication of data and / or signals, whether via a wired or wireless connection. Communication system 1400 may include and interface with any type of communication, telecommunications, data, cellular, radio network, and / or other similar type of system.

[0156] UE 1412 can be any of a variety of communication devices, including wireless devices that are arranged, configured, and / or operable to communicate wirelessly with network node 1410 and other communication devices. Similarly, network node 1410 is arranged, capable, configured, and / or operable to communicate directly or indirectly with UE 1412 and / or with other network nodes or devices in telecommunication network 1402 to achieve and / or provide network access (such as wireless network access) and / or perform other functions (such as management in telecommunication network 1402).

[0157] In the depicted example, core network 1406 connects network node 1410 to one or more hosts, such as host 1416. These connections can be direct or indirect connections via one or more intermediate networks or devices. In other examples, network nodes can be directly coupled to hosts. Core network 1406 includes one or more core network nodes (e.g., core network node 1408) constructed with hardware and software components. The characteristics of these components can be substantially similar to those described with respect to UEs, network nodes, and / or hosts, such that the description generally applies to the corresponding components of core network node 1408. Example core network nodes include functions of one or more of the following: Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier Dehiding Function (SIDF), Unified Data Management (UDM), Secure Edge Protection Agent (SEPP), Network Open Function (NEF), and / or User Plane Function (UPF).

[0158] Host 1416 may be under the ownership or control of a service provider other than the operator or provider of access network 1404 and / or telecommunications network 1402, and may be operated by or on behalf of the service provider. Host 1416 may host various applications to provide one or more services. Examples of such applications include providing real-time and / or pre-recorded audio / video content, data collection services (e.g., retrieving and editing data on various environmental conditions detected by multiple UEs), analytics functions, social media, functions for controlling or otherwise interacting with remote devices, functions for alarm and monitoring centers, or any other such functions performed by the server.

[0159] As a whole, Figure 14 The communication system 1400 enables connectivity between the UE, network nodes, and hosts. In this sense, the communication system can be configured to operate according to predefined rules or procedures such as specific standards, including but not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard (WiFi); and / or any other suitable wireless communication standards, such as Microwave Access Global Interoperability (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC), ZigBee, LiFi, and / or any Low Power Wide Area Network (LPWAN) standards such as LoRa and Sigfox.

[0160] In some examples, telecommunications network 1402 is a cellular network implementing 3GPP standardized features. Therefore, telecommunications network 1402 can support network slicing to provide different logical networks to different devices connected to it. For example, telecommunications network 1402 can provide ultra-reliable low-latency communication (URLLC) services to some UEs while providing enhanced mobile broadband (eMBB) services to other UEs, and / or massive machine-type communication (mMTC) / massive IoT services to yet another UE.

[0161] In some examples, UE 1412 is configured to send and / or receive information without direct human interaction. For example, when triggered by an internal or external event, or in response to a request from access network 1404, the UE can be designed to send information to access network 1404 according to a predetermined schedule. Additionally, the UE can be configured to operate in single RAT, multi-RAT, or multi-standard modes. For example, the UE can operate using any one or a combination of Wi-Fi, NR (New Radio), and LTE, i.e., configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved UMTS Terrestrial Radio Access Network) New Radio Dual Connectivity (EN-DC).

[0162] exist Figure 14In the example illustrated, hub 1414 communicates with access network 1404 to facilitate indirect communication between one or more UEs (e.g., UEs 1412c and / or 1412d) and network nodes (e.g., network node 1410b). In some examples, hub 1414 may be a controller, router, content source, and analytics node, or any of the other communication devices described herein with respect to the UE. For example, hub 1414 may be a broadband router that enables the UE to access core network 1406. As another example, hub 1414 may be a controller that sends commands or instructions to one or more actuators in the UE. Commands or instructions may be received from the UE, network node 1410, or via executable code, scripts, procedures, or other instructions in hub 1414. As another example, hub 1414 may be a data collector that acts as a temporary storage device for UE data, and in some embodiments, may perform data analysis or other processing. As another example, hub 1414 may be a content source. For example, for a UE acting as a VR headset, display, speaker, or other media delivery device, hub 1414 can retrieve VR assets, video, audio, or other media or data related to sensory information via network nodes, and then provide them to the UE directly, after performing local processing, and / or after adding additional local content. In yet another example, hub 1414 acts as a proxy server or coordinator for the UE, particularly when one or more devices in the UE are low-power IoT devices.

[0163] The hub 1414 may have a constant / persistent or intermittent connection to network node 1410b. The hub 1414 may also allow different communication schemes and / or scheduling between the hub 1414 and UEs (e.g., UEs 1412c and / or 1412d) and between the hub 1414 and the core network 1406. In other examples, the hub 1414 is connected to the core network 1406 and / or one or more UEs via a wired connection. Furthermore, the hub 1414 may be configured to connect to an M2M service provider via access network 1404 and / or to another UE via a direct connection. In some scenarios, a UE may establish a wireless connection with network node 1410 while still being connected via the hub 1414 via a wired or wireless connection. In some embodiments, the hub 1414 may be a dedicated hub, meaning its primary function is to route communication from network node 1410b to the UE and from the UE to network node 1410b. In other embodiments, the hub 1414 may be a non-dedicated hub, that is, a device that can operate to route communication between the UE and the network node 1410b, but can also operate as a communication start point and / or end point for certain data channels.

[0164] Figure 15 A UE 1500 is illustrated according to some embodiments. As used herein, a UE refers to a device capable of, configured, positioned, and / or operable to wirelessly communicate with network nodes and / or other UEs. Examples of UEs include, but are not limited to, smartphones, mobile phones, cellular phones, Voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, game consoles or devices, music storage devices, playback devices, wearable terminal devices, wireless endpoints, mobile stations, tablets, laptops, laptop embedded devices (LEEs), laptop mounted devices (LMEs), smart devices, wireless customer premises equipment (CPEs), vehicles, in-vehicle or vehicle-embedded / integrated wireless devices, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including Narrowband Internet of Things (NB-IoT) UEs, Machine Type Communication (MTC) UEs, and / or Enhanced MTC (eMTC) UEs.

[0165] The UE can support device-to-device (D2D) communication, for example, by implementing 3GPP standards for sidelink communication, dedicated short-range communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, the UE may not necessarily be a user in the sense of a human user who owns and / or operates the associated equipment. Instead, the UE may represent equipment intended to be sold to or operated by a human user, but the equipment may not be associated with a particular human user, or may not have initially been associated with that particular human user (e.g., a smart sprinkler controller). Alternatively, the UE may represent equipment not intended to be sold to or operated by an end user, but the equipment may be associated with a user or operated for the user's benefit (e.g., a smart meter).

[0166] UE 1500 includes processing circuitry 1502, operatively coupled via bus 1504 to input / output interface 1506, power supply 1508, memory 1510, communication interface 1512, and / or any other components, or any combination thereof. Some UEs may utilize... Figure 15 The components shown may be all or a subset of the components. The level of integration between components can vary from one UE to another. Furthermore, some UEs may contain multiple instances of components, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0167] Processing circuitry 1502 is configured to process instructions and data and can be configured to implement any sequential state machine operable to execute instructions stored in memory 1510 as a machine-readable computer program. Processing circuitry 1502 can be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), etc.); programmable logic and appropriate firmware; one or more stored computer programs, general-purpose processors such as microprocessors or digital signal processors (DSPs), and appropriate software; or any combination thereof. For example, processing circuitry 1502 may include multiple central processing units (CPUs). Processing circuitry 1502 can be operable to provide UE 1500 functionality, either alone or in combination with other UE 1500 components, such as memory 1510. For example, processing circuitry 1502 can be configured to cause UE 1502 to execute reference... Figure 11 The method described.

[0168] In this example, the input / output interface 1506 can be configured to provide one or more interfaces to input devices, output devices, or one or more input and / or output devices. Examples of output devices include speakers, sound cards, video cards, displays, monitors, printers, actuators, transmitters, smart cards, other output devices, or any combination thereof. Input devices can allow users to capture information into the UE 1500. Examples of input devices include touch-sensitive or presence-sensitive displays, cameras (e.g., digital cameras, digital camcorders, webcams, etc.), microphones, sensors, mice, trackballs, steering wheels, scroll wheels, smart cards, etc. Presence-sensitive displays may include capacitive or resistive touch sensors to sense input from the user. Sensors may be, for example, accelerometers, gyroscopes, tilt sensors, force sensors, magnetometers, optical sensors, proximity sensors, biometric sensors, etc., or any combination thereof. Output devices can use the same type of interface port as input devices. For example, a Universal Serial Bus (USB) port can be used to provide both input and output devices.

[0169] In some embodiments, power supply 1508 is configured as a battery or battery pack. Other types of power sources can be used, such as external power sources (e.g., electrical outlets), photovoltaic devices, or power batteries. Power supply 1508 may also include power circuitry for delivering power from power supply 1508 itself and / or external power sources to various parts of UE 1500 via input circuitry or an interface such as a power cable. The delivered power may be used, for example, to charge power supply 1508. The power circuitry may perform any formatting, conversion, or other modifications on the power from power supply 1508 to suit the power supply for the various components of UE 1500 to which power is supplied.

[0170] Memory 1510 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), disk, optical disk, hard disk, removable tape cartridge, flash drive, etc. In one example, memory 1510 includes one or more applications 1514, such as an operating system, web browser application, widget, utility engine, or other application, and corresponding data 1516. Memory 1510 can store any operating system or combination of operating systems from various operating systems for use by UE 1500.

[0171] The memory 1510 can be configured to include multiple physical drive units, such as a redundant array of independent disks (RAID), flash memory, USB flash drive, external hard drive, thumb drive, pen drive, key drive, high-density digital multifunction disc (HD-DVD) optical disc drive, internal hard drive, Blu-ray disc drive, holographic digital data storage (HDDS) optical disc drive, external mini dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro DIMM SDRAM, smart card memory (such as a tamper-proof module in the form of a universal integrated circuit card (UICC), including one or more user identity modules (SIMs), such as USIM and / or ISIM), other memory, or any combination thereof. The UICC can be, for example, an embedded UICC (eUICC), an integrated UICC (iUICC), or a removable UICC commonly referred to as a "SIM card". The memory 1510 can allow the UE to... 1500 Accesses instructions, applications, etc., stored on temporary or non-temporary storage media to unload or upload data. Manufactured articles, such as those utilizing communication systems, may be tangibly embodied in or contained within memory 1510, which may be or include device-readable storage media.

[0172] Processing circuitry 1502 can be configured to communicate with an access network or other network using communication interface 1512. Communication interface 1512 may include one or more communication subsystems and may include or be communicatively coupled to antenna 1522. Communication interface 1512 may include one or more transceivers for communication, such as through one or more remote transceivers capable of wireless communication with another device (e.g., another UE or network node in the access network). Each transceiver may include a transmitter 1518 and / or a receiver 1520 adapted to provide network communication (e.g., optical, electrical, frequency allocation, etc.). Furthermore, transmitter 1518 and receiver 1520 may be coupled to one or more antennas (e.g., antenna 1522) and may share circuitry, software, or firmware, or alternatively, may be implemented separately.

[0173] In some embodiments, the communication functions of the communication interface 1512 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communication such as Bluetooth, near-field communication, location-based communication such as using a Global Positioning System (GPS) to determine location, another similar communication function, or any combination thereof. Communication may be implemented according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, Transmission Control Protocol / Internet Protocol (TCP / IP), Synchronous Optical Networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so on.

[0174] Regardless of the type of sensor, the UE can provide the output of data captured by its sensors via its communication interface 1512, through a wireless connection to the network node. Data captured by the UE's sensors can be transmitted wirelessly to the network node via another UE. The output can be periodic (e.g., every 15 minutes if it reports sensed temperature), random (e.g., to load balance reports from multiple sensors), responsive to a triggered event (e.g., sending an alarm when humidity is detected), responsive to a request (e.g., a user-initiated request), or a continuous stream (e.g., real-time video feed of a patient).

[0175] As another example, the UE includes an actuator, motor, or switch associated with a communication interface configured to receive wireless input from a network node via a wireless connection. The state of the actuator, motor, or switch can change in response to the received wireless input. For example, the UE may include a motor that adjusts the control surfaces or rotors of a flying drone based on the received input, or control a robotic arm to perform a medical procedure based on the received input.

[0176] When taking the form of an Internet of Things (IoT) device, the UE can be a device used in one or more application areas, including but not limited to urban wearable technology, extended industrial applications, and healthcare. Non-limiting examples of such IoT devices include or embedded in the following devices: connected refrigerators or freezers, TVs, connected lighting fixtures, electricity meters, robotic vacuum cleaners, voice-activated smart speakers, home security cameras, motion detectors, thermostats, smoke detectors, door / window sensors, flood / humidity sensors, electric door locks, connected doorbells, air conditioning systems (such as heat pumps), autonomous vehicles, surveillance systems, weather monitoring equipment, vehicle parking monitoring equipment, electric vehicle charging stations, smartwatches, fitness trackers, head-mounted displays for augmented reality (AR) or virtual reality (VR), wearable devices for haptic or sensory enhancement, sprinklers, animal or object tracking devices, sensors for monitoring plants or animals, industrial robots, unmanned aerial vehicles (UAVs), and any kind of medical device (such as heart rate monitors or remotely controlled surgical robots). (Except for...) Figure 15 In addition to the other components described in UE 1500 shown, UEs in the form of IoT devices include circuitry and / or software that depend on the intended application of the IoT device.

[0177] As another concrete example, in IoT scenarios, a UE can represent a machine or other device that performs monitoring and / or measurement and sends the results of such monitoring and / or measurement to another UE and / or network node. In this case, the UE can be an M2M device, which can be referred to as an MTC device in the 3GPP context. As a specific example, the UE can implement the 3GPP NB-IoT standard. In other scenarios, the UE can represent a vehicle, such as a car, bus, truck, ship, and aircraft, or other device capable of monitoring and / or reporting its operational status or performing other functions associated with its operation.

[0178] In practice, for a single use case, any number of UEs can be used together. For example, the first UE might be or integrated into the drone and provide the drone's speed information (obtained via a speed sensor) to a second UE acting as a remote controller. When the user makes a change from the remote controller, the first UE can adjust the throttle on the drone (e.g., by controlling actuators) to increase or decrease the drone's speed. The first and / or second UEs may also include more than one of the functions described above. For example, the UE might include sensors and actuators and handle communication for data from the speed sensors and actuators.

[0179] Figure 16 A network node 1600 according to some embodiments is shown. As used herein, a network node refers to a device that is capable of, configured, arranged, and / or operable to communicate directly or indirectly with a UE and / or other network nodes or devices in a telecommunications network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs), and NR Node Bs (gNBs)), O-RAN nodes, or components of O-RAN nodes (e.g., O-RUs, O-DUs, O-CUs).

[0180] Base stations can be classified based on the coverage they provide (or, in other words, based on their transmit power levels); therefore, depending on the coverage provided, a base station can be referred to as a femtobase, picobase, microbase, or macrobase. A base station can be a relay node or a relay donor node controlling a relay. Network nodes can also include one or more (or all) portions of a distributed radio base station, such as centralized digital units, distributed units (e.g., in O-RAN access nodes), and / or remote radio units (RRUs), sometimes referred to as remote radio heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna-integrated radio. A portion of a distributed radio base station can also be referred to as a node in a distributed antenna system (DAS).

[0181] Other examples of network nodes include multi-transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) devices such as MSR BS, network controllers such as radio network controllers (RNC) or base station controllers (BSC), base transceiver stations (BTS), transmission points, transmission nodes, multi-cell / multicast coordination entities (MCE), operations and maintenance (O&M) nodes, operations support system (OSS) nodes, self-organizing network (SON) nodes, location nodes (e.g., evolved servicing mobile location centers (E-SMLC)), and / or minimized drive tests (MDT).

[0182] Network node 1600 includes processing circuitry 1602, memory 1604, communication interface 1606, and power supply 1608 and / or any other components or any combination thereof. Network node 1600 may consist of multiple physically separate components (e.g., NodeB components and RNC components, or BTS components and BSC components, etc.), each component may have its own corresponding components. In some scenarios where network node 1600 includes multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC can control multiple NodeBs. In such scenarios, each unique NodeB and RNC pair may be considered a single separate network node in some cases. In some embodiments, network node 1600 may be configured to support multiple Radio Access Technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 1604 for different RATs), and some components may be reused (e.g., the same antenna 1610 may be shared by different RATs). Network node 1600 may also include multiple sets of various illustrated components for integrating different wireless technologies (such as GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, radio frequency identification (RFID), or Bluetooth wireless technologies) into network node 1600. These wireless technologies may be integrated into the same or different chips or chipsets and other components within network node 1600.

[0183] Processing circuitry 1602 may include one or more of a microprocessor, controller, central processing unit, digital signal processor, application-specific integrated circuit, field-programmable gate array, or any other suitable computing device, resource, or combination of hardware, software, and / or coding logic, operable to provide the functionality of network node 1600, either alone or in conjunction with other network node 1600 components, such as memory 1604. For example, processing circuitry 1602 may be configured to cause the network node to perform reference... Figure 7 , 9 Or any one or more of the methods described in 10.

[0184] In some embodiments, the processing circuitry 1602 includes a system-on-a-chip (SOC). In some embodiments, the processing circuitry 1602 includes one or more of a radio frequency (RF) transceiver circuitry 1612 and a baseband processing circuitry 1614. In some embodiments, the RF transceiver circuitry 1612 and the baseband processing circuitry 1614 may be on separate chips (or chipsets), boards, or units, such as radio units and digital units. In alternative embodiments, some or all of the RF transceiver circuitry 1612 and the baseband processing circuitry 1614 may be on the same chip or chipset, board, or unit.

[0185] Memory 1604 may include any form of volatile or non-volatile computer-readable memory, including but not limited to persistent storage devices, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (e.g., hard disk), removable storage media (e.g., flash drives, compact discs (CDs), or digital video discs (DVDs)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory device that stores information, data, and / or instructions that can be used by processing circuitry 1602. Memory 1604 may store any suitable instructions, data, or information, including computer programs, software, and applications, including one or more of logic, rules, codes, tables, and / or other instructions that can be executed by processing circuitry 1602 and utilized by network node 1600. Memory 1604 may be used to store any calculations performed by processing circuitry 1602 and / or any data received via communication interface 1606. In some embodiments, processing circuitry 1602 and memory 1604 are integrated.

[0186] Communication interface 1606 is used for wired or wireless communication of signaling and / or data between network nodes, access networks, and / or UEs. As shown, communication interface 1606 includes one or more ports / terminals 1616 for transmitting and receiving data to and from the network, for example, via a wired connection. Communication interface 1606 also includes radio front-end circuitry 1618, which may be coupled to antenna 1610, or in some embodiments, is part of antenna 1610. Radio front-end circuitry 1618 includes filter 1620 and amplifier 1622. Radio front-end circuitry 1618 may be connected to antenna 1610 and processing circuitry 1602. Radio front-end circuitry 1618 may be configured to modulate the signal transmitted between antenna 1610 and processing circuitry 1602. Radio front-end circuitry 1618 may receive digital data to be transmitted to other network nodes or UEs via a wireless connection. Radio front-end circuitry 1618 may use a combination of filter 1620 and / or amplifier 1622 to convert the digital data into radio signals with appropriate channel and bandwidth parameters. The radio signals may then be transmitted via antenna 1610. Similarly, when receiving data, antenna 1610 can collect radio signals, which are then converted into digital data by radio front-end circuitry 1618. The digital data can then be passed to processing circuitry 1602. In other embodiments, the communication interface may include different components and / or different combinations of components.

[0187] In some alternative embodiments, network node 1600 does not include a separate radio front-end circuitry 1618; instead, processing circuitry 1602 includes the radio front-end circuitry and is connected to antenna 1610. Similarly, in some embodiments, all or part of RF transceiver circuitry 1612 is part of communication interface 1606. In other embodiments, communication interface 1606 includes one or more ports or terminals 1616, radio front-end circuitry 1618, and RF transceiver circuitry 1612 as part of a radio unit (not shown), and communication interface 1606 communicates with baseband processing circuitry 1614 as part of a digital unit (not shown).

[0188] Antenna 1610 may include one or more antennas or antenna arrays configured to transmit and / or receive wireless signals. Antenna 1610 may be coupled to radio front-end circuitry 1618 and may be any type of antenna capable of wirelessly transmitting and receiving data and / or signals. In some embodiments, antenna 1610 is decoupled from network node 1600 and may be connected to network node 1600 via an interface or port.

[0189] Antenna 1610, communication interface 1606, and / or processing circuitry 1602 can be configured to perform any receive operation and / or certain acquisition operation described herein as being performed by a network node. Any information, data, and / or signals can be received from the UE, another network node, and / or any other network device. Similarly, antenna 1610, communication interface 1606, and / or processing circuitry 1602 can be configured to perform any transmit operation described herein as being performed by a network node. Any information, data, and / or signals can be transmitted to the UE, another network node, and / or any other network device.

[0190] Power supply 1608 provides power to the various components of network node 1600 in a form suitable for each component (e.g., at the voltage and current levels required by each respective component). Power supply 1608 may further include or be coupled to power management circuitry to supply power to the components of network node 1600 for performing the functions described herein. For example, network node 1600 may be connected to an external power source (e.g., mains, electrical outlet) via input circuitry or interface such as a cable, whereby the external power source supplies power to the power circuitry of power supply 1608. As another example, power supply 1608 may include a power source in the form of a battery or battery pack, which is connected to or integrated into the power circuitry. The battery can provide backup power if the external power source fails.

[0191] Embodiments of network node 1600 may include Figure 16 Additional components beyond those shown are used to provide certain aspects of the network node's functionality, including any of the functions described herein and / or any functions necessary to support the topics described herein. For example, network node 1600 may include a user interface device to allow information to be input into and output from network node 1600. This allows users to perform diagnostic, maintenance, repair, and other management functions of network node 1600.

[0192] While the computing devices described herein (e.g., UE, network node, host) may include the illustrated combinations of hardware components, other embodiments may include computing devices with different combinations of components. It should be understood that these computing devices may include any suitable combination of hardware and / or software required to perform the tasks, features, functions, and methods disclosed herein. The determination, calculation, acquisition, or similar operations described herein may be performed by processing circuitry that processes information by, for example, converting acquired information into other information, comparing the acquired or converted information with information stored in a network node, and / or performing one or more operations based on the acquired or converted information, and making a determination as a result of said processing. Furthermore, although components are depicted as single boxes located within larger boxes or nested within multiple boxes, in practice, computing devices may include multiple different physical components constituting a single illustrated component, and functionality may be partitioned between individual components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of a component may be partitioned between processing circuitry and the communication interface. In another example, non-computationally intensive functions of any such component may be implemented in software or firmware, and computationally intensive functions may be implemented in hardware.

[0193] In some embodiments, some or all of the functions described herein may be provided by processing circuitry that executes instructions stored in memory, which in some embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functions may be provided by processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of these particular embodiments, the processing circuitry may be configured to perform the described functions, whether or not instructions stored on a non-transitory computer-readable storage medium are executed. The benefits provided by such functions are not limited to the processing circuitry itself or other components of the computing device, but are enjoyed by the computing device as a whole and / or generally by the end user and wireless network.

Claims

1. A method performed by a network node in a communication network for configuring a Physical Downlink Control Channel (PDCCH) search space for a User Equipment (UE), the method comprising: A reduced aggregation level AL search space configuration is sent to the UE, wherein the reduced AL search space configuration includes only a candidate set of control channel elements (CCEs) in ALs that are lower than the maximum aggregation level available in the communication network.

2. The method as described in claim 1, wherein, The reduced AL search space configuration includes only the candidate set of control channel elements in AL1 to AL4 or AL1 to AL8.

3. The method as described in claim 1 or 2, wherein, The reduced AL search space configuration is sent as part of a Radio Resource Control (RRC) message.

4. The method according to any one of claims 1 to 3, further comprising: In response to determining that the PDCCH transmission to the UE should be performed using a first AL at a first transmit power, wherein the first AL is not included in the reduced AL search space configuration, the PDCCH transmission is performed using a second AL included in the reduced AL search space configuration at a second transmit power higher than the first transmit power.

5. The method of claim 4, further comprising: Based on the mapping of the first AL to the downlink channel quality associated with the UE, it is determined that the PDCCH transmission to the UE should utilize the first AL.

6. The method of claim 5, further comprising: The downlink channel quality is determined based on one or more of the following: channel state information reports from the UE, HARQ feedback from the UE, and uplink reference signals received from the UE.

7. The method according to any one of claims 4 to 6, wherein, The first AL includes AL N, and the second AL includes AL N / M, where N is an integer and M is another integer, and where the first transmit power includes X W and the second transmit power includes MX W.

8. The method according to any one of claims 1 to 3, further comprising: Estimate the downlink SINR associated with the UE, i.e., SINR_est; Map the SINR_est to the first AL, wherein the first AL is included in the reduced AL search space configuration; The first transmit power is determined based on the nominal transmit power assumed for SINR_est and the minimum downlink SINR, i.e., SINR_AL_s, where the first AL has a minimum threshold probability for successful reception at the UE for the minimum downlink SINR; and The PDCCH transmission is carried out using the candidate set of CCEs in the first AL at the first transmit power.

9. The method of claim 8, wherein, Determining the first transmit power includes: determining the first transmit power as 1 or the maximum value in SINR_AL_s / SINR_est multiplied by the nominal transmit power.

10. The method of any one of claims 1 to 9, further comprising: In response to determining that the PDCCH blocking level in the cell serving the first UE meets a first threshold condition associated with a first threshold blocking level, the step of sending the reduced AL search space configuration is performed.

11. The method of claim 10, further comprising: In response to determining that the PDCCH blocking level in the cell serving the UE does not meet the first threshold condition associated with the first threshold blocking level, a normal search space configuration is sent to the UE.

12. The method of claim 10 or 11, wherein: In response to the PDCCH blocking level satisfying the first threshold condition associated with the first threshold blocking level and the second threshold condition associated with the second threshold blocking level, the reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs that are lower than at least the highest Y aggregation levels available in the communication network, where Y is an integer greater than or equal to 1.

13. The method of claim 12, wherein: In response to the PDCCH blocking level satisfying the first threshold condition associated with the first threshold blocking level and not satisfying the second threshold condition associated with the second threshold blocking level, the reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs that are lower than at least the highest Z aggregation levels available in the communication network, where Z is an integer and Z>Y.

14. The method of any one of claims 11 to 13, further comprising: The PDCCH blocking level is determined based on one or more of the following: The ratio of the time periods in the cell where PDCCH blocking occurs across multiple time periods; The average number of unused shared channel PRBs of the type required by the UE in the cell over multiple time periods.

15. A method for configuring the physical downlink control channel (PDCCH) search space, performed by a user equipment in a communication network, the method comprising: Receive a reduced aggregation level AL search space configuration from the network node, wherein the reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs lower than the maximum AL available in the communication network.

16. The method of claim 15, wherein, The reduced AL search space configuration includes only the candidate set of control channel elements in AL1 to AL4.

17. The method of claim 15 or 16, wherein, The reduced AL search space configuration is sent as part of a Radio Resource Control (RRC) message.

18. A network node in a communication network for configuring a Physical Downlink Control Channel (PDCCH) search space for a User Equipment (UE), the network node comprising processing circuitry and a memory, the memory containing instructions executable by the processing circuitry, thereby enabling the network node to: Send a reduced aggregation level AL search space configuration to the UE, wherein, The reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs that are lower than the maximum aggregation level available in the communication network.

19. The network node as described in claim 18, wherein, The memory contains further instructions executable by the processing circuitry, thereby enabling the network node to perform the method as described in any one of claims 2 to 14.

20. A user equipment in a communication network for configuring a physical downlink control channel (PDCCH) search space, the user equipment including processing circuitry and a memory, the memory containing instructions executable by the processing circuitry, thereby enabling the user equipment to: Receive the reduced aggregation-level AL search space configuration from the network nodes, where... The reduced AL search space configuration includes only the candidate set of control channel elements (CCEs) in ALs lower than the maximum AL available in the communication network.

21. The user equipment as claimed in claim 20, wherein, The memory contains further instructions executable by the processing circuitry, thereby enabling the user equipment to perform the method as described in any one of claims 16 or 17.

22. A computer program comprising instructions that, when executed on at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 17.

23. A carrier comprising the computer program as described in claim 22, wherein, The carrier includes one of electronic signals, optical signals, radio signals, or computer-readable storage media.

24. A computer-readable medium comprising instructions that, when executed on at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 17.

25. A computer program product comprising a non-transitory computer-readable medium having thereon the computer program of claim 22 stored thereon.

Images