WO2023050308A1

WO2023050308A1 - Methods and apparatus of meeting ue memory requirement for decoding of enhanced pdcch

Info

Publication number: WO2023050308A1
Application number: PCT/CN2021/122170
Authority: WO
Inventors: Yi Zhang; Wei Ling; Chenxi Zhu; Bingchao LIU; Lingling Xiao
Original assignee: Lenovo (Beijing) Limited
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-04-06

Abstract

Methods and apparatus of meeting UE memory requirement for decoding of enhanced Physical Downlink Control Channel (PDCCH) are disclosed. The method includes: transmitting, by a transmitter, a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and receiving, by a receiver, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

Description

METHODS AND APPARATUS OF MEETING UE MEMORY REQUIREMENT FOR DECODING OF ENHANCED PDCCH

FIELD

The subject matter disclosed herein relates generally to wireless communication and more particularly relates to, but not limited to, methods and apparatus of meeting UE memory requirement for decoding of enhanced Physical Downlink Control Channel (PDCCH) .

BACKGROUND

The following abbreviations and acronyms are herewith defined, at least some of which are referred to within the specification:

Third Generation Partnership Project (3GPP) , 5th Generation (5G) , New Radio (NR) , 5G Node B (gNB) , Long Term Evolution (LTE) , LTE Advanced (LTE-A) , E-UTRAN Node B (eNB) , Universal Mobile Telecommunications System (UMTS) , Worldwide Interoperability for Microwave Access (WiMAX) , Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) , Wireless Local Area Networking (WLAN) , Orthogonal Frequency Division Multiplexing (OFDM) , Single-Carrier Frequency-Division Multiple Access (SC-FDMA) , Downlink (DL) , Uplink (UL) , User Entity/Equipment (UE) , Network Equipment (NE) , Radio Access Technology (RAT) , Receive or Receiver (RX) , Transmit or Transmitter (TX) , Physical Downlink Control Channel (PDCCH) , Enhanced Physical Downlink Control Channel (ePDCCH) , Bandwidth Part (BWP) , Control Channel Element (CCE) , Control Resource Set (CORESET) , Downlink Control Information (DCI) , Frequency Division Multiple Access (FDMA) , Index (ID) , Radio Resource Control (RRC) , Subcarrier Spacing (SCS) , Synchronization Signal Block (SSB) , Transmission and Reception Point (TRP) , Frequency Range 1 (FR1) , Frequency Range 2 (FR2) , Transmission Configuration Indication (TCI) , Quasi Co-Location (QCL) , Log Likelihood Ratio (LLR) , Blind Detection (BD) .

In wireless communication, such as a Third Generation Partnership Project (3GPP) mobile network, a wireless mobile network may provide a seamless wireless communication service to a wireless communication terminal having mobility, i.e., user equipment (UE) . The wireless mobile network may be formed of a plurality of base stations and a base station may perform wireless communication with the UEs.

The 5G New Radio (NR) is the latest in the series of 3GPP standards which supports very high data rate with lower latency compared to its predecessor LTE (4G) technology. Two types of frequency range (FR) are defined in 3GPP. Frequency of sub-6 GHz range (from 450 to 6000 MHz) is called FR1 and millimeter wave range (from 24.25 GHz to 52.6 GHz) is called FR2. The 5G NR supports both FR1 and FR2 frequency bands.

Enhancements on multi-TRP/panel transmission including improved reliability and robustness with both ideal and non-ideal backhaul between these TRPs (Transmit Receive Points) are studied. A TRP is an apparatus to transmit and receive signals, and is controlled by a gNB through the backhaul between the gNB and the TRP. A TRP may also be referred to as a transmitting-receiving identity, or simply an identity.

In current NR system, Physical Downlink Control Channel (PDCCH) is transmitted from a single TRP. With multiple TRPs, time-frequency resources for PDCCH transmission may be from multiple TRPs. The spatial diversity may be exploited in addition to the time-frequency diversity. Enhanced Physical Downlink Control Channel (ePDCCH) may be transmitted with multiple repetition from multiple TRPs to improve PDCCH transmission reliability and robustness. Multiple transmissions of the ePDCCH may be transmitted from a same TRP or some different TRPs.

In order to support enhanced PDCCH, UE complexity and/or memory requirement for linked PDCCH candidates have to be considered.

SUMMARY

Methods and apparatus of meeting UE memory requirement for decoding of enhanced PDCCH are disclosed.

According to a first aspect, there is provided a method, including: transmitting, by a transmitter, a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and receiving, by a receiver, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

According to a second aspect, there is provided a method, including: receiving, by a receiver, a capability parameter for decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and transmitting, by a transmitter, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

According to a third aspect, there is provided an apparatus, including: a transmitter that transmits a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and a receiver that receives a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

According to a fourth aspect, there is provided an apparatus, including: a receiver that receives a capability parameter for decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and a transmitter that transmits a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments will be rendered by reference to specific embodiments illustrated in the appended drawings. Given that these drawings depict only some embodiments and are not therefore considered to be limiting in scope, the embodiments will be described and explained with additional specificity and details through the use of the accompanying drawings, in which:

Figure 1 is a schematic diagram illustrating a wireless communication system in accordance with some implementations of the present disclosure;

Figure 2 is a schematic block diagram illustrating components of user equipment (UE) in accordance with some implementations of the present disclosure;

Figure 3 is a schematic block diagram illustrating components of network equipment (NE) in accordance with some implementations of the present disclosure;

Figures 4A and 4B are schematic diagrams illustrating examples of schemes for meeting soft buffer size requirement based on soft buffer life time on candidate pair level and candidate level in accordance with some implementations of the present disclosure;

Figures 5A and 5B are schematic diagrams illustrating examples on the impact of interval between linked candidates on soft buffer size in accordance with some implementations of the present disclosure;

Figures 6A to 6C are schematic diagrams illustrating examples on the impact of interval between PDCCH pairs on soft buffer size in accordance with some implementations of the present disclosure;

Figure 7 is a flow chart illustrating steps of meeting UE memory requirement for decoding of enhanced PDCCH by UE in accordance with some implementations of the present disclosure; and

Figure 8 is a flow chart illustrating steps of meeting UE memory requirement for decoding of enhanced PDCCH by gNB in accordance with some implementations of the present disclosure.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art, aspects of the embodiments may be embodied as a system, an apparatus, a method, or a program product. Accordingly, embodiments may take the form of an all-hardware embodiment, an all-software embodiment (including firmware, resident software, micro-code, etc. ) or an embodiment combining software and hardware aspects.

Furthermore, one or more embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine readable code, computer readable code, and/or program code, referred to hereafter as “code. ” The storage devices may be tangible, non-transitory, and/or non-transmission.

Reference throughout this specification to “one embodiment, ” “an embodiment, ” “an example, ” “some embodiments, ” “some examples, ” or similar language means that a particular feature, structure, or characteristic described is included in at least one embodiment or example. Thus, instances of the phrases “in one embodiment, ” “in an example, ” “in some embodiments, ” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment (s) . It may or may not include all the embodiments disclosed. Features, structures, elements, or characteristics described in connection with one or some embodiments are also applicable to other embodiments, unless expressly specified otherwise. The terms “including, ” “comprising, ” “having, ” and variations thereof mean “including but not limited to, ” unless expressly specified otherwise.

An enumerated listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a, ” “an, ” and “the” also refer to “one or more” unless expressly specified otherwise.

Throughout the disclosure, the terms “first, ” “second, ” “third, ” and etc. are all used as nomenclature only for references to relevant devices, components, procedural steps, and etc. without implying any spatial or chronological orders, unless expressly specified otherwise. For example, a “first device” and a “second device” may refer to two separately formed devices, or two parts or components of the same device. In some cases, for example, a “first device” and a “second device” may be identical, and may be named arbitrarily. Similarly, a “first step” of a method or process may be carried or performed after, or simultaneously with, a “second step. ”

It should be understood that the term “and/or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items. For example, “A and/or B” may refer to any one of the following three combinations: existence of A only, existence of B only, and co-existence of both A and B. The character “/” generally indicates an “or” relationship of the associated items. This, however, may also include an “and” relationship of the associated items. For example, “A/B” means “A or B, ” which may also include the co-existence of both A and B, unless the context indicates otherwise.

Furthermore, the described features, structures, or characteristics of the embodiments may be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments. One skilled in the relevant art will recognize, however, that embodiments may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of an embodiment.

Aspects of various embodiments are described below with reference to schematic flowchart diagrams and/or schematic block diagrams of methods, apparatuses, systems, and program products. It will be understood that each block of the schematic flowchart diagrams and/or schematic block diagrams, as well as combinations of blocks in the schematic flowchart diagrams and/or schematic block diagrams, may be implemented by code. This code may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions executed via the processor of the computer or other programmable data processing apparatus create a means for implementing the functions or acts specified in the schematic flowchart diagrams and/or schematic block diagrams.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function or act specified in the schematic flowchart diagrams and/or schematic block diagrams.

The schematic flowchart diagrams and/or schematic block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of different apparatuses, systems, methods, and program products according to various embodiments. In this regard, each block in the schematic flowchart diagrams and/or schematic block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions of the code for implementing the specified logical function (s) . One skilled in the relevant art will recognize, however, that the flowchart diagrams need not necessarily be practiced in the sequence shown and are able to be practiced without one or more of the specific steps, or with other steps not shown.

It should also be noted that, in some alternative implementations, the functions noted in the identified blocks may occur out of the order noted in the Figures. For example, two blocks shown in succession may, in fact, be substantially executed in concurrence, or the blocks may sometimes be executed in reverse order, depending upon the functionality involved.

Figure 1 is a schematic diagram illustrating a wireless communication system. It depicts an embodiment of a wireless communication system 100. In one embodiment, the wireless communication system 100 may include a user equipment (UE) 102 and a network equipment (NE) 104. Even though a specific number of UEs 102 and NEs 104 is depicted in Figure 1, one skilled in the art will recognize that any number of UEs 102 and NEs 104 may be included in the wireless communication system 100.

The UEs 102 may be referred to as remote devices, remote units, subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, user terminals, apparatus, devices, or by other terminology used in the art.

In one embodiment, the UEs 102 may be autonomous sensor devices, alarm devices, actuator devices, remote control devices, or the like. In some other embodiments, the UEs 102 may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs) , tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet) , set-top boxes, game consoles, security systems (including security cameras) , vehicle on-board computers, network devices (e.g., routers, switches, modems) , or the like. In some embodiments, the UEs 102 include wearable devices, such as smart watches, fitness bands, optical head-mounted displays, or the like. The UEs 102 may communicate directly with one or more of the NEs 104.

The NE 104 may also be referred to as a base station, an access point, an access terminal, a base, a Node-B, an eNB, a gNB, a Home Node-B, a relay node, an apparatus, a device, or by any other terminology used in the art. Throughout this specification, a reference to a base station may refer to any one of the above referenced types of the network equipment 104, such as the eNB and the gNB.

The NEs 104 may be distributed over a geographic region. The NE 104 is generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding NEs 104. The radio access network is generally communicably coupled to one or more core networks, which may be coupled to other networks, like the Internet and public switched telephone networks. These and other elements of radio access and core networks are not illustrated, but are well known generally by those having ordinary skill in the art.

In one implementation, the wireless communication system 100 is compliant with a 3GPP 5G new radio (NR) . In some implementations, the wireless communication system 100 is compliant with a 3GPP protocol, where the NEs 104 transmit using an OFDM modulation scheme on the DL and the UEs 102 transmit on the uplink (UL) using a SC-FDMA scheme or an OFDM scheme. More generally, however, the wireless communication system 100 may implement some other open or proprietary communication protocols, for example, WiMAX. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

The NE 104 may serve a number of UEs 102 within a serving area, for example, a cell (or a cell sector) or more cells via a wireless communication link. The NE 104 transmits DL communication signals to serve the UEs 102 in the time, frequency, and/or spatial domain.

Communication links are provided between the NE 104 and the

UEs

102a, 102b, 102c, and 102d, which may be NR UL or DL communication links, for example. Some UEs 102 may simultaneously communicate with different Radio Access Technologies (RATs) , such as NR and LTE. Direct or indirect communication link between two or more NEs 104 may be provided.

The NE 104 may also include one or more transmit receive points (TRPs) 104a. In some embodiments, the network equipment may be a gNB 104 that controls a number of TRPs 104a. In addition, there is a backhaul between two TRPs 104a. In some other embodiments, the network equipment may be a TRP 104a that is controlled by a gNB.

Communication links are provided between the

NEs

104, 104a and the

UEs

102, 102a, respectively, which, for example, may be NR UL/DL communication links. Some

UEs

102, 102a may simultaneously communicate with different Radio Access Technologies (RATs) , such as NR and LTE.

In some embodiments, the UE 102a may be able to communicate with two or more TRPs 104a that utilize a non-ideal backhaul, simultaneously. A TRP may be a transmission point of a gNB. Multiple beams may be used by the UE and/or TRP (s) . The two or more TRPs may be TRPs of different gNBs, or a same gNB. That is, different TRPs may have the same Cell-ID or different Cell-IDs. The terms “TRP” and “transmitting-receiving identity” may be used interchangeably throughout the disclosure.

The technology disclosed, or at least some of the examples, may be applicable to scenarios with multiple TRPs or without multiple TRPs, as long as multiple PDCCH transmissions are supported.

Figure 2 is a schematic block diagram illustrating components of user equipment (UE) according to one embodiment. A UE 200 may include a processor 202, a memory 204, an input device 206, a display 208, and a transceiver 210. In some embodiments, the input device 206 and the display 208 are combined into a single device, such as a touchscreen. In certain embodiments, the UE 200 may not include any input device 206 and/or display 208. In various embodiments, the UE 200 may include one or more processors 202 and may not include the input device 206 and/or the display 208.

The processor 202, in one embodiment, may include any known controller capable of executing computer-readable instructions and/or capable of performing logical operations. For example, the processor 202 may be a microcontroller, a microprocessor, a central processing unit (CPU) , a graphics processing unit (GPU) , an auxiliary processing unit, a field programmable gate array (FPGA) , or similar programmable controller. In some embodiments, the processor 202 executes instructions stored in the memory 204 to perform the methods and routines described herein. The processor 202 is communicatively coupled to the memory 204 and the transceiver 210.

The memory 204, in one embodiment, is a computer readable storage medium. In some embodiments, the memory 204 includes volatile computer storage media. For example, the memory 204 may include a RAM, including dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , and/or static RAM (SRAM) . In some embodiments, the memory 204 includes non-volatile computer storage media. For example, the memory 204 may include a hard disk drive, a flash memory, or any other suitable non-volatile computer storage device. In some embodiments, the memory 204 includes both volatile and non-volatile computer storage media. In some embodiments, the memory 204 stores data relating to trigger conditions for transmitting the measurement report to the network equipment. In some embodiments, the memory 204 also stores program code and related data.

The input device 206, in one embodiment, may include any known computer input device including a touch panel, a button, a keyboard, a stylus, a microphone, or the like. In some embodiments, the input device 206 may be integrated with the display 208, for example, as a touchscreen or similar touch-sensitive display.

The display 208, in one embodiment, may include any known electronically controllable display or display device. The display 208 may be designed to output visual, audio, and/or haptic signals.

The transceiver 210, in one embodiment, is configured to communicate wirelessly with the network equipment. In certain embodiments, the transceiver 210 comprises a transmitter 212 and a receiver 214. The transmitter 212 is used to transmit UL communication signals to the network equipment and the receiver 214 is used to receive DL communication signals from the network equipment.

The transmitter 212 and the receiver 214 may be any suitable type of transmitters and receivers. Although only one transmitter 212 and one receiver 214 are illustrated, the transceiver 210 may have any suitable number of transmitters 212 and receivers 214. For example, in some embodiments, the UE 200 includes a plurality of the transmitter 212 and the receiver 214 pairs for communicating on a plurality of wireless networks and/or radio frequency bands, with each of the transmitter 212 and the receiver 214 pairs configured to communicate on a different wireless network and/or radio frequency band.

Figure 3 is a schematic block diagram illustrating components of network equipment (NE) 300 according to one embodiment. The NE 300 may include a processor 302, a memory 304, an input device 306, a display 308, and a transceiver 310. As may be appreciated, the processor 302, the memory 304, the input device 306, the display 308, and the transceiver 310 may be similar to the processor 202, the memory 204, the input device 206, the display 208, and the transceiver 210 of the UE 200, respectively.

In some embodiments, the processor 302 controls the transceiver 310 to transmit DL signals or data to the UE 200. The processor 302 may also control the transceiver 310 to receive UL signals or data from the UE 200. In another example, the processor 302 may control the transceiver 310 to transmit DL signals containing various configuration data to the UE 200.

In some embodiments, the transceiver 310 comprises a transmitter 312 and a receiver 314. The transmitter 312 is used to transmit DL communication signals to the UE 200 and the receiver 314 is used to receive UL communication signals from the UE 200.

The transceiver 310 may communicate simultaneously with a plurality of UEs 200. For example, the transmitter 312 may transmit DL communication signals to the UE 200. As another example, the receiver 314 may simultaneously receive UL communication signals from the UE 200. The transmitter 312 and the receiver 314 may be any suitable type of transmitters and receivers. Although only one transmitter 312 and one receiver 314 are illustrated, the transceiver 310 may have any suitable number of transmitters 312 and receivers 314. For example, the NE 300 may serve multiple cells and/or cell sectors, where the transceiver 310 includes a transmitter 312 and a receiver 314 for each cell or cell sector.

For normal PDCCH, the soft buffer is linked with blind decoding. Thus, the capability for soft buffer is associated with the maximum blind decoding (BD) number.

For enhanced PDCCH transmission with repetition, soft combining may be used to improve transmission reliability. The soft buffer size is increased for linked PDCCH candidates on account of soft combining; and occupation time (i.e., occupancy time) also becomes longer because the soft buffer for decoding PDCCH that starts early cannot be released as it may be used for blind decoding with soft combining for PDCCH starting later.

For normal PDCCH transmission, there is no explicit definition of soft buffer size in the current 3GPP specification. In realization, it is more related with PDCCH decoding. It may be assumed that the soft buffer size is implicitly associated with a maximum value of candidate number and/or non-overlapping CCE number. The related contents for defining the maximum candidate number and non-overlapping CCE number in the current 3GPP specification are shown as follows.

Table 1 provides the maximum number of monitored PDCCH candidates,

per slot for a UE in a DL BWP with SCS configuration μ for operation with a single serving cell.

Table 1. Maximum number

of monitored PDCCH candidates per slot for a DL BWP with SCS configuration μ∈ {0, 1, 2, 3} for a single serving cell

Table 2 provides the maximum number of monitored PDCCH candidates,

per span for a UE in a DL BWP with SCS configuration μ for operation with a single serving cell.

Table 2. Maximum number

of monitored PDCCH candidates in a span for combination (X, Y) for a DL BWP with SCS configuration μ∈ {0, 1} for a single serving cell

Table 3 provides the maximum number of non-overlapped CCEs,

for a DL BWP with SCS configuration μ that a UE is expected to monitor corresponding PDCCH candidates per slot for operation with a single serving cell.

CCEs for PDCCH candidates are non-overlapped if they correspond to:

- different CORESET indexes, or

- different first symbols for the reception of the respective PDCCH candidates.

Table 3. Maximum number

of non-overlapped CCEs per slot for a DL BWP with SCS configuration μ∈ {0, 1, 2, 3} for a single serving cell

Table 4 provides the maximum number of non-overlapped CCEs,

for a DL BWP with SCS configuration μ that a UE is expected to monitor corresponding PDCCH candidates per span for operation with a single serving cell.

Table 4. Maximum number

of non-overlapped CCEs in a span for combination (X, Y) for a DL BWP with SCS configuration μ∈ {0, 1} for a single serving cell

Thus, a maximum number of monitored PDCCH candidates and/or non-overlapping CCEs per slot and per span may be defined to meet UE decoding complexity for PDCCH.

For PDCCH with repetition transmission, the required soft buffer size may increase on account of soft combining. Thus, the linked candidate number has an impact on the required soft buffer size.

For decoding, the soft buffer for decoding PDCCH transmitted earlier may not be emptied or reused until the completion of blind detection based on soft combining operation with PDCCH transmitted later. Thus, occupation time for soft buffer is also increased, especially when there is a large time interval between two linked monitoring occasions.

Furthermore, the soft buffer size may increase when there is overlapping of occupation time between different linked monitoring occasion pairs. Schemes for meeting UE memory requirement for decoding PDCCH with repetition are proposed. Several schemes are proposed based on soft buffer life time; and some configuration restrictions on search space sets are proposed to match the soft buffer size and the related UE capability reporting.

A. Schemes Based on Restriction on Candidate Number

Similar to Release 15, some basic association between the soft buffer size and the PDCCH candidate number may be assumed. Additional soft buffer size and long occupying time may be introduced in the case of enhanced PDCCH transmission with repetition. It is desirable to guarantee that the used or required soft buffer size is no larger than the maximum buffer size in UE at any time. This means that the total equivalent candidate number for candidates taking up the soft buffer from all search space sets on a time unit (or a point in time) is required to be no larger than the supported maximum equivalent candidate number from soft buffer view.

For decoding of the candidates, the soft buffer is used to store Log Likelihood Ratio (LLR) , where the used or required soft buffer size is related with the used CCE number. Thus, different soft buffer sizes may be used for candidates with different aggregation levels.

For example, the soft buffer size for the candidate with aggregation level of 8 may be twice, four times, and eight times, of that for candidate with aggregation levels of 4, 2, and 1, respectively.

Equivalent candidate number may be introduced to denote the soft buffer size, where a weight coefficient may be used for evaluating candidates with different aggregation levels.

For example, a weight coefficient for candidate with

aggregation level

1, 2, 4, or 8, may be 1, 2, 4, or 8, respectively, on account of the relation with the actual used CCE number. The weight coefficients may be configured values or fixed values. In some other examples, the weight coefficients may have predefined values of (1, 2, 4, 8) , or (1, 1, 1, 1) or (0, 0, 0, 1) . The predefined values may be determined by typical UE realization schemes. Based on the equivalent candidate number, actual buffer size, e.g. k bytes, may be derived by an implicit mapping relation.

Definition for life time of soft buffer

To evaluate the used or required soft buffer size on any one time unit, life time of the soft buffer may also be introduced or defined. Naturally, the soft buffer is taken up during the life time, and is released after the life time.

The life time of soft buffer may be defined on candidate pair level or on candidate level. When it is defined on the candidate pair level, the life time may be defined as the time interval from the start time of the first PDCCH candidate to the end of PDCCH decoding including decoding based on combined LLR if soft combining is used.

When it is defined on candidate level, the life time of soft buffer is defined for each linked candidate. For the first candidate, the life time is defined as the time interval from the start time of the first linked candidate to the end of PDCCH decoding including decoding based on combined LLR if soft combining is used. For the second candidate, the life time is defined as the time interval from the start time of the second linked candidate to the end of PDCCH decoding including decoding based on combined LLR if soft combining is used. In this example, the first candidate may refer to an initial transmission of a PDCCH candidate; and the second candidate may refer to a repeating transmission of the PDCCH candidate. In the disclosure, the definition of life time may be described with respect to candidates. It is reasonable that the definition of life time may also be described with respect to associated monitoring occasions of the candidates. It can serve as another realization scheme. For example, for the first candidate, the life time is defined as the time interval from the start time of the monitoring occasion associated with the first linked candidate to the end of PDCCH decoding including decoding based on combined LLR if soft combining is used.

For individual decoding or decoding for normal PDCCH, the soft buffer life time is the same for candidate from normal PDCCH. Thus, the soft buffer life time may be better defined on candidate level as normal PDCCH, for example, as the time interval from the starting of an individual candidate to the end of PDCCH decoding with individual decoding.

Figures 4A and 4B are schematic diagrams illustrating examples of schemes for meeting soft buffer size requirement based on soft buffer life time on candidate pair level and candidate level in accordance with some implementations of the present disclosure.

In one example as shown in Figure 4A, the used soft buffer size is based on soft buffer life time defined on candidate pair level; and in another example as shown in Figure 4B, the used soft buffer size is based on soft buffer life time defined on candidate level.

In Figures 4A and 4B, there are four monitoring occasions from two pairs of linked search space sets, where 11 candidates are configured for each monitoring occasion of four search space sets.

As shown in Figure 4A, with life time on candidate pair level, a first soft buffer life time 412 and a second soft buffer life time 414 per candidate pair level are defined: the first soft buffer life time 412 for the first linked monitoring occasion pair 402 for monitoring a first group of 22 candidates (or 11 candidates with repetition) ; and the second soft buffer life time 414 for the second linked monitoring occasion pair 404 for monitoring a second group of 22 candidates (or 11 candidates with repetition) . The total equivalent candidate number, or the soft buffer size 420, for candidates in life time from all search space sets is 22, 44, and 22, for the three different time periods as shown in Figure 4A, respectively.

As shown in Figure 4B, with life time on candidate level, four instances of soft

buffer life time

411, 413, 415 and 417 per candidate level are defined: a first soft buffer life time 411 and a second soft buffer life time 413 for the first linked monitoring occasion pair 402, each for monitoring 11 candidates or repetition; and a third soft buffer life time 415 and a fourth soft buffer life time 417 for the second linked monitoring occasion pair 404, each for monitoring 11 candidates or repetition. The total equivalent candidate number, or the soft buffer size 420, for candidates in life time from all search space sets is 11, 22, 33, 44, and 22 for the five different time periods as shown in Figure 4B, respectively.

In this example, if the UE supports maximum 44 equivalent candidates at any time from soft buffer size view, the related configuration with two linked search space set pairs may be supported.

In this example, reference to candidate number is reference to equivalent candidate number.

In summary, the UE expects that the used soft buffer size is no larger than the maximum buffer size on any time unit, where the used soft buffer size on a time unit is denoted by the total equivalent candidate number from all search space sets if the current time unit (i.e., the current point in time) is in their soft buffer life time and the maximum buffer size is denoted by the supported maximum equivalent candidate number from soft buffer size view.

The soft buffer life time is defined on candidate pair level or candidate level, which is defined as the time interval from the start time of the first PDCCH candidate to the end of PDCCH decoding on candidate pair level, or as the time interval from the start time of the corresponding candidate to the end of PDCCH decoding on candidate level.

Determining equivalent candidate number

To determine equivalent candidate number, two aspects are considered.

The first aspect is how to count candidates from a candidate pair from view of determining associated soft buffer size. For limiting blind detection number, it is agreed that UE may report 2 or 3 as the required number of blind detection for the two paired (i.e., linked) PDCCH candidates. Similar counting schemes may be used for determining candidate number which is used to determine the used soft buffer size. In detail, the reported value (i.e., value 2 or 3) may be used as counting candidate number when the soft buffer life time is defined on candidate pair level. When the soft buffer life time is defined on candidate level, the

values

1 and 1 may be used as counting the first and second linked candidates, respectively, in the case of reporting value as 2 for blind detection; and the

values

1 and 2 may be used as counting the first and second linked candidates, respectively, in the case of reporting value as 3 for blind detection.

The second aspect is weight processing for candidates with different aggregation levels. As one example, when a candidate with

aggregation level

1, 2, 4, or 8 is used, the

weigh coefficient

1, 2, 4, or 8 is used, respectively, when counting total equivalent candidate number on account of the used CCE number. As another example, the

weigh coefficient

1, 1, 1, or 1 is used for candidate with

aggregation level

1, 2, 4, or 8, respectively. As a further example, the weigh coefficient 0, 0, 0, or 1 is used for candidate with

aggregation level

1, 2, 4, or 8, respectively.

Thus, for determining the used soft buffer size with life time on candidate pair level,

value

2 or 3 may be used as counting two linked candidates in the case of reporting value as 2 or 3 for blind detection. For determining the used soft buffer size with life time on candidate level, values 1 and 1 may be used as counting the first and second linked candidates in the case of reporting value as 2 for blind detection, respectively; and the

values

1 and 2 may be used as counting the first and second linked candidates in the case of reporting value as 3 for blind detection, respectively. Total equivalent candidate number is determined by counting candidates from all search space sets with the

weight coefficient

1, 2, 4, or 8 for candidates with

aggregation level

1, 2, 4, or 8, respectively.

UE capability reporting to determine life time of soft buffer

For soft buffer life time, it is related with: 1) transmission time of the two linked candidates which may be determined by the configuration of CORESETs or search space sets; 2) time for blind detection which is related with the processing time for ePDCCH.

To determine soft buffer life time, a processing time may be introduced, with value as x symbols, which denotes the time interval from the ending symbol of the second linked candidate or associated monitoring occasion to the end of PDCCH decoding including decoding based on combined LLR if soft combining is used. In some examples, the time interval may start from the end time of the second linked candidate. In some examples, the time interval may start from the end time of the monitoring occasion associated with the second linked candidate. With the processing time introduced, the soft buffer life time on candidate pair level or on candidate level may be derived based on the processing time and the candidate pair/candidate time location derived by the configuration of the linked CORESETs or search space sets. Value x may be defined in the specification as a fixed value, e.g., 4 OFDM symbols, which is determined based on the processing capability of low end UE. Alternatively or optionally, value x may be reported by UE in a capability parameter as UE capability.

The value x may be extended to in the use of determining the soft buffer life time for individual decoding for enhanced PDCCH or normal PDCCH by replacing the second linked candidate with the PDCCH candidate on account of PDCCH transmission without repetition.

Value x may be subcarrier spacing (SCS) specific, where one specific x is defined for a SCS.

In summary, a specific fixed value x may be defined or reported by UE for determining soft buffer life time, which denotes the time interval starting from the ending symbol of the second linked candidate or associated monitoring occasion to the end of PDCCH decoding.

UE capability reporting on maximum equivalent candidate number

For maximum equivalent candidate number from soft buffer size view, it may reuse the equivalent candidate number concept by counting weighted maximum candidate number defined for blind detection as shown in Table 1 or Table 2 above.

In some examples, a specific weight coefficient for candidate with

aggregation level

1, 2, 4, or 8 may be 1, 2, 4, or 8, respectively. The weight coefficients may have configured values or fixed values. In some other examples, the weight coefficients may have predefined values of (1, 2, 4, 8) , or (1, 1, 1, 1) or (0, 0, 0, 1) .

The weight coefficient may be a new value for the maximum equivalent candidate number defined from UE capability. In some examples, the number may be defined based on one specific aggregation level, e.g., aggregation level 1. In some examples, the number may be defined per aggregation level. This means one maximum number for each aggregation level. The capability is denoted by the union set of maximum number for each aggregation level. In some other examples, the new value may be configured when there is mismatching between UE processing capability and soft buffer size. For example, a large value may be configured when the soft buffer size is large for some UEs and it may support more flexible configuration on search space sets, e.g., overlapping between multiple monitoring occasion pairs.

In summary, the maximum equivalent candidate number defined for soft buffer size may be determined by counting weighted maximum candidate number defined for blind detection or by a new reported value based on a specific aggregation level as UE capability.

B. Schemes Based on Restriction on RRC Configuration of Linked Search Space Sets

Figures 5A and 5B are schematic diagrams illustrating examples on the impact of interval between linked candidates on soft buffer size in accordance with some implementations of the present disclosure.

As shown in Figures 5A and 5B, the used or required soft buffer size is shown for 2 cases with

different time intervals

502, 504, and 506, 508, between linked PDCCH monitoring occasions. In this example, the time interval between linked PDCCH monitoring occasions refers to a time period from an end of the first monitoring occasion to a start of the second monitoring occasion of the linked PDCCH monitoring occasions. In the two cases, the

time interval

506, 508 between the linked monitoring occasions in case 2 is larger than the

time interval

502, 504 in case 1. Based on the results shown in Figures 5A and 5B, it may be noted that the soft buffer life time is increased with increasing time interval between the linked monitoring occasions. Thus, the occupation time for soft buffer is also increased with increasing time interval between the linked monitoring occasions. Thus, it will bring some restriction on scheduling other search space sets on account of some soft buffer still being taken. The situation becomes worse when inter-slot and inter-span repetition for PDCCH is used.

Therefore, some restriction on the maximum time interval between the linked monitoring occasions is proposed, e.g., y OFDM symbols, where y may be 0, 2, 4, 7 or other values. That is, the maximum OFDM symbol number between two linked monitoring occasions may be restricted as 0, 2, 4, 7 or other value. In the special case where y is restricted to be 0, the two linked monitoring occasions are consecutive monitoring occasions.

Figures 6A to 6C are schematic diagrams illustrating examples on the impact of interval between PDCCH pairs on soft buffer size in accordance with some implementations of the present disclosure.

As shown in Figures 6A to 6C, the required soft buffer size for 3 cases with different time intervals between the first monitoring occasion pair and the second monitoring occasion pair is illustrated. Different DCIs are monitored on the first and second monitoring occasion pairs.

In case 1 as shown in Figure 6A, there is time overlapping 602 between the soft buffer life time for the second linked monitoring occasion pair for the second linked candidate pair (PDCCH pair 2) and the soft buffer life time for the first linked monitoring occasion pair for the first linked candidate pair (PDCCH pair 1) .

In case 2 as shown in Figure 6B, there is no time overlapping (i.e. the overlapping time 604 is zero) between the soft buffer life time for the second monitoring occasion pair and the soft buffer life time for the first linked monitoring occasion pair.

In case 3 as shown in Figure 6C, there is time overlapping 606 between the first monitoring occasion pair and the second monitoring occasion pair, besides the time overlapping between the soft buffer life time for the second linked monitoring occasion pair and the soft buffer life time for first linked monitoring occasion pair.

Based on the used soft buffer shown in Figures 6A to 6C, it may be noted that smaller soft buffer size, i.e., associated with 22 candidates, is required for case 2 shown in Figure 6B, where there is no overlapping with the soft buffer life time. For the overlapping case 1 shown in Figure 6A and the overlapping case 3 show in Figure 6C, they have the same used soft buffer size, i.e., associated with 44 candidates. The usage time for soft buffer associated with 44 candidates is longer for case 3.

From this example, it may be observed that the used soft buffer size is related with the time interval between two monitoring occasion pairs. The time interval between the two monitoring occasion pairs, denoted as z symbols, may be defined as starting from the ending symbol of the second monitoring occasion of the first monitoring occasion pair and ending at the starting symbol of the first monitoring occasion of the second monitoring occasion pair. The UE may report the supported maximum time interval between two monitoring occasion pairs based on its capability on soft buffer size and processing capability.

In some examples, the UE may report the supported minimum time interval between two monitoring occasion pairs. In some other examples, the UE may report a supported maximum overlapping time between two monitoring occasion pairs, or a supported maximum overlapping time between two soft buffer life times for two monitoring occasion pairs.

The gNB may configure monitoring occasions for search space sets carrying different DCIs following restriction derived by UE’s reporting. The reported value z may be a value between 0 and x for case 1 (Figure 6A) , or value x (as defined previously) for case 2 (Figure 6B) , or a value with a negative integer for case 3 (Figure 6C) .

The values y and/or z may also be subcarrier spacing (SCS) specific, where one specific y, z is defined for a SCS.

In summary, the maximum time interval between two monitoring occasion pairs, each monitoring occasion pair for a PDCCH carrying a different DCI, may be reported as UE capability and gNb follows this restriction for configuring search space sets.

Figure 7 is a flow chart illustrating steps of meeting UE memory requirement for decoding of enhanced PDCCH by UE 200 in accordance with some implementations of the present disclosure.

At step 702, the transmitter 212 of UE 200 transmits a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission.

At step 704, the receiver 214 of UE 200 receives a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

Figure 8 is a flow chart illustrating steps of meeting UE memory requirement for decoding of enhanced PDCCH by gNB or NE 300 in accordance with some implementations of the present disclosure.

At step 802, the receiver 314 of NE 300 receives a capability parameter for decoding Physical Downlink Control Channel (PDCCH) with repetition transmission.

At step 804, the transmitter 312 of NE 300 transmits a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

In one aspect, some items as examples of the disclosure concerning a method of a UE or remote device may be summarized as follows:

1. A method, comprising:

transmitting, by a transmitter, a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and

receiving, by a receiver, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

2. The method of item 1, wherein the capability parameter comprises a maximum equivalent candidate number derived based on a maximum number of candidates defined for blind detection and corresponding aggregation level.

3. The method of item 1, wherein the capability parameter comprises a maximum equivalent candidate number derived by a fixed value, or an RRC configured value based on a specific aggregation level.

4. The method of item 1, wherein the PDCCH candidates received from the linked search space sets are restricted such that, a total equivalent candidate number at any time is not greater than the maximum equivalent candidate number, the total equivalent candidate number at a time being derived based on the number of PDCCH candidates at the time from all search space sets and corresponding aggregation level.

5. The method of item 4, wherein the total equivalent candidate number is obtained by counting the PDCCH candidates based on a first time interval between:

a starting symbol of a monitoring occasion or a candidate for the PDCCH transmission with repetition, and

completion of decoding the PDCCH transmission with repetition.

6. The method of item 1, wherein the capability parameter comprises a second time interval between:

an ending symbol of a later one of the linked monitoring occasions or a later one of the linked candidates for the PDCCH transmission with repetition; and

completion of decoding the PDCCH transmission with repetition.

7. The method of item 5, wherein a weight coefficient is used for deriving equivalent candidate numbers for each aggregation level of the PDCCH candidates.

8. The method of item 5, wherein the first time interval is defined on candidate pair level, and

value

2 or 3 is used as counting two linked candidates in the case of reporting value as 2 or 3 for blind detection.

9. The method of item 5, wherein the first time interval is defined on candidate level, and

values

1 and 1 are used as counting a first linked candidate and a second linked candidate, respectively, in the case of reporting value as 2 for blind detection.

10. The method of item 5, wherein the first time interval is defined on candidate level, and

values

1 and 2 are used as counting a first linked candidate and a second linked candidate, respectively, in the case of reporting value as 3 for blind detection.

11. The method of item 6, wherein the second time interval has a fixed value.

12. The method of item 1, wherein the linked monitoring occasions are restricted with a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

13. The method of item 12, wherein the maximum time interval is 0 symbol, 2 symbols, 4 symbols, or 7 symbols.

14. The method of item 1, wherein the capability parameter comprises a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

15. The method of item 1, wherein the linked monitoring occasions are restricted such that a time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI, is within a time limit obtainable from the capability parameter or from a specific fixed value.

16. The method of item 1, wherein the capability parameter comprises an allowable time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI.

17. The method of item 6, 14 or 16, wherein the second time interval, the maximum time interval, or the allowable time interval, is subcarrier space specific.

In another aspect, some items as examples of the disclosure concerning a method of a NE or gNB may be summarized as follows:

18. A method, comprising:

receiving, by a receiver, a capability parameter for decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and

transmitting, by a transmitter, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

19. The method of item 18, wherein the capability parameter comprises a maximum equivalent candidate number derived based on a maximum number of candidates defined for blind detection and corresponding aggregation level.

20. The method of item 18, wherein the capability parameter comprises a maximum equivalent candidate number derived by a fixed value, or an RRC configured value based on a specific aggregation level.

21. The method of item 18, wherein the PDCCH candidates in the linked search space sets are restricted such that, a total equivalent candidate number at any time is not greater than the maximum equivalent candidate number, the total equivalent candidate number at a time being derived based on the number of PDCCH candidates at the time from all search space sets and corresponding aggregation level.

22. The method of item 21, wherein the total equivalent candidate number is obtained by counting the PDCCH candidates based on a first time interval between:

completion of decoding the PDCCH transmission with repetition.

23. The method of item 18, wherein the capability parameter comprises a second time interval between:

completion of decoding the PDCCH transmission with repetition.

24. The method of item 22, wherein a weight coefficient is used for deriving equivalent candidate numbers for each aggregation level of the PDCCH candidates.

25. The method of item 22, wherein the first time interval is defined on candidate pair level, and

value

26. The method of item 22, wherein the first time interval is defined on candidate level, and

values

27. The method of item 22, wherein the first time interval is defined on candidate level, and

values

28. The method of item 23, wherein the second time interval has a fixed value.

29. The method of item 18, wherein the linked monitoring occasions are restricted with a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

30. The method of item 29, wherein the maximum time interval is 0 symbol, 2 symbols, 4 symbols, or 7 symbols.

31. The method of item 18, wherein the capability parameter comprises a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

32. The method of item 18, wherein the linked monitoring occasions are restricted such that a time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI, is within a time limit obtainable from the capability parameter or from a specific fixed value.

33. The method of item 18, wherein the capability parameter comprises an allowable time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI.

34. The method of item 23, 31 or 33, wherein the second time interval, the maximum time interval, or the allowable time interval, is subcarrier space specific.

In a further aspect, some items as examples of the disclosure concerning a UE or remote device may be summarized as follows:

35. An apparatus, comprising:

a transmitter that transmits a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and

a receiver that receives a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

36. The apparatus of item 35, wherein the capability parameter comprises a maximum equivalent candidate number derived based on a maximum number of candidates defined for blind detection and corresponding aggregation level.

37. The apparatus of item 35, wherein the capability parameter comprises a maximum equivalent candidate number derived by a fixed value, or an RRC configured value based on a specific aggregation level.

38. The apparatus of item 35, wherein the PDCCH candidates received from the linked search space sets are restricted such that, a total equivalent candidate number at any time is not greater than the maximum equivalent candidate number, the total equivalent candidate number at a time being derived based on the number of PDCCH candidates at the time from all search space sets and corresponding aggregation level.

39. The apparatus of item 38, wherein the total equivalent candidate number is obtained by counting the PDCCH candidates based on a first time interval between:

completion of decoding the PDCCH transmission with repetition.

40. The apparatus of item 35, wherein the capability parameter comprises a second time interval between:

completion of decoding the PDCCH transmission with repetition.

41. The apparatus of item 39, wherein a weight coefficient is used for deriving equivalent candidate numbers for each aggregation level of the PDCCH candidates.

42. The apparatus of item 39, wherein the first time interval is defined on candidate pair level, and

value

43. The apparatus of item 39, wherein the first time interval is defined on candidate level, and

values

44. The apparatus of item 39, wherein the first time interval is defined on candidate level, and

values

45. The apparatus of item 40, wherein the second time interval has a fixed value.

46. The apparatus of item 35, wherein the linked monitoring occasions are restricted with a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

47. The apparatus of item 46, wherein the maximum time interval is 0 symbol, 2 symbols, 4 symbols, or 7 symbols.

48. The apparatus of item 35, wherein the capability parameter comprises a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

49. The apparatus of item 35, wherein the linked monitoring occasions are restricted such that a time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI, is within a time limit obtainable from the capability parameter or from a specific fixed value.

50. The apparatus of item 35, wherein the capability parameter comprises an allowable time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI.

51. The apparatus of item 40, 48 or 50, wherein the second time interval, the maximum time interval, or the allowable time interval, is subcarrier space specific.

In a yet further aspect, some items as examples of the disclosure concerning a NE or gNB may be summarized as follows:

52. An apparatus, comprising:

a receiver that receives a capability parameter for decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and

a transmitter that transmits a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.

53. The apparatus of item 52, wherein the capability parameter comprises a maximum equivalent candidate number derived based on a maximum number of candidates defined for blind detection and corresponding aggregation level.

54. The apparatus of item 52, wherein the capability parameter comprises a maximum equivalent candidate number derived by a fixed value, or an RRC configured value based on a specific aggregation level.

55. The apparatus of item 52, wherein the PDCCH candidates in the linked search space sets are restricted such that, a total equivalent candidate number at any time is not greater than the maximum equivalent candidate number, the total equivalent candidate number at a time being derived based on the number of PDCCH candidates at the time from all search space sets and corresponding aggregation level.

56. The apparatus of item 55, wherein the total equivalent candidate number is obtained by counting the PDCCH candidates based on a first time interval between:

completion of decoding the PDCCH transmission with repetition.

57. The apparatus of item 52, wherein the capability parameter comprises a second time interval between:

completion of decoding the PDCCH transmission with repetition.

58. The apparatus of item 56, wherein a weight coefficient is used for deriving equivalent candidate numbers for each aggregation level of the PDCCH candidates.

59. The apparatus of item 56, wherein the first time interval is defined on candidate pair level, and

value

60. The apparatus of item 56, wherein the first time interval is defined on candidate level, and

values

61. The apparatus of item 56, wherein the first time interval is defined on candidate level, and

values

62. The apparatus of item 57, wherein the second time interval has a fixed value.

63. The apparatus of item 52, wherein the linked monitoring occasions are restricted with a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

64. The apparatus of item 63, wherein the maximum time interval is 0 symbol, 2 symbols, 4 symbols, or 7 symbols.

65. The apparatus of item 52, wherein the capability parameter comprises a maximum time interval between two of the linked monitoring occasions from two linked search space sets.

66. The apparatus of item 52, wherein the linked monitoring occasions are restricted such that a time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI, is within a time limit obtainable from the capability parameter or from a specific fixed value.

67. The apparatus of item 52, wherein the capability parameter comprises an allowable time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI.

68. The apparatus of item 57, 65, or 67, wherein the second time interval, the maximum time interval, or the allowable time interval, is subcarrier space specific.

Various embodiments and/or examples are disclosed to provide exemplary and explanatory information to enable a person of ordinary skill in the art to put the disclosure into practice. Features or components disclosed with reference to one embodiment or example are also applicable to all embodiments or examples unless specifically indicated otherwise.

Embodiments may be practiced in other specific forms. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

A method, comprising:

transmitting, by a transmitter, a capability parameter for receiving and decoding Physical Downlink Control Channel (PDCCH) with repetition transmission; and

receiving, by a receiver, a configuration of linked search space sets with a number of PDCCH candidates that are restricted based on the capability parameter, and/or a configuration of linked monitoring occasions, from linked search space sets for blind detection of the PDCCH with repetition transmission, that are restricted.
The method of claim 1, wherein the capability parameter comprises a maximum equivalent candidate number derived based on a maximum number of candidates defined for blind detection and corresponding aggregation level.
The method of claim 1, wherein the capability parameter comprises a maximum equivalent candidate number derived by a fixed value, or an RRC configured value based on a specific aggregation level.
The method of claim 1, wherein the PDCCH candidates received from the linked search space sets are restricted such that, a total equivalent candidate number at any time is not greater than the maximum equivalent candidate number, the total equivalent candidate number at a time being derived based on the number of PDCCH candidates at the time from all search space sets and corresponding aggregation level.
The method of claim 4, wherein the total equivalent candidate number is obtained by counting the PDCCH candidates based on a first time interval between:

a starting symbol of a monitoring occasion or a candidate for the PDCCH transmission with repetition, and

completion of decoding the PDCCH transmission with repetition.
The method of claim 1, wherein the capability parameter comprises a second time interval between:

an ending symbol of a later one of the linked monitoring occasions or a later one of the linked candidates for the PDCCH transmission with repetition; and

completion of decoding the PDCCH transmission with repetition.
The method of claim 5, wherein a weight coefficient is used for deriving equivalent candidate numbers for each aggregation level of the PDCCH candidates.
The method of claim 5, wherein the first time interval is defined on candidate pair level, and value 2 or 3 is used as counting two linked candidates in the case of reporting value as 2 or 3 for blind detection.
The method of claim 5, wherein the first time interval is defined on candidate level, and values 1 and 1 are used as counting a first linked candidate and a second linked candidate, respectively, in the case of reporting value as 2 for blind detection; or the first time interval is defined on candidate level, and values 1 and 2 are used as counting a first linked candidate and a second linked candidate, respectively, in the case of reporting value as 3 for blind detection.
The method of claim 1, wherein the linked monitoring occasions are restricted with a maximum time interval between two of the linked monitoring occasions from two linked search space sets.
The method of claim 10, wherein the maximum time interval is 0 symbol, 2 symbols, 4 symbols, or 7 symbols.
The method of claim 1, wherein the capability parameter comprises a maximum time interval between two of the linked monitoring occasions from two linked search space sets.
The method of claim 1, wherein the linked monitoring occasions are restricted such that a time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI, is within a time limit obtainable from the capability parameter or from a specific fixed value.
The method of claim 1, wherein the capability parameter comprises an allowable time interval between a first linked monitoring occasion pair and a second linked monitoring pair, each for a PDCCH carrying a different DCI.
The method of claim 6, 12 or 14, wherein the second time interval, the maximum time interval, or the allowable time interval, is subcarrier space specific.