CN113545144B

CN113545144B - Transmission and receiving method and device for enhanced physical downlink control channel

Info

Publication number: CN113545144B
Application number: CN201980093745.8A
Authority: CN
Inventors: 郭力
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2019-08-08
Filing date: 2019-12-03
Publication date: 2023-08-29
Anticipated expiration: 2039-12-03
Also published as: CN113545144A; WO2021022736A1

Abstract

A method and apparatus for transmitting and receiving an enhanced Physical Downlink Control Channel (PDCCH). The first control resource set (CORESET) is repeated in a PDCCH transmission by transmitting a first copy of first Downlink Control Information (DCI) in a first PDCCH candidate allocated to the first DCI and transmitting a second copy of the first DCI in a second PDCCH candidate allocated to the second CORESET. The first CORESET and the second CORESET are associated with a first set of search spaces. When the reception apparatus receives and acquires the repeated first DCI and the correlated configuration of the first DCI, the reception apparatus acquires the first DCI from the first and second copies of the first DCI by using the correlated configuration of the first DCI.

Description

Transmission and receiving method and device for enhanced physical downlink control channel

Background

1. Technical field

The present application relates to the field of communications systems, and in particular, to a method and apparatus for transmitting and receiving an enhanced PDCCH.

2. Description of related Art

As formulated by The third generation partnership project (The 3rd Generation Partnership Project,3GPP), the currently designed physical downlink control channel (physical downlink control channel, PDCCH) can only support The transmission of PDCCH from a single transmitting receiving node (transmission reception point, TRP) without addressing PDCCH reliability issues.

The TRP with the best channel conditions may be selected and the PDCCH transmitted to a User Equipment (UE). The channel condition between the UE and one TRP may change dynamically, but the configuration of the search space for monitoring the PDCCH is semi-static and cannot closely track the change of the radio channel. Reconfiguring the search space for monitoring the PDCCH requires time and results in longer delay and more signaling overhead.

Accordingly, there is a need for a transmission apparatus and method of enhanced PDCCH.

Disclosure of Invention

The application aims to provide a method and a device for transmitting and receiving an enhanced PDCCH, which can improve the reliability.

In a first aspect of the present application, there is provided a method of enhancing PDCCH transmission, the method being executable by an apparatus and comprising: the transmission of the first DCI is repeated by transmitting a first copy of first downlink control information (downlink control information, DCI) in a first PDCCH candidate allocated to a first set of control resources (control resource set, CORESET) and a second copy of the first DCI in a second PDCCH candidate allocated to a second CORESET, wherein the first CORESET and the second CORESET are associated with a first set of search spaces.

In a second aspect of the present application, there is provided a method of enhancing PDCCH reception, the method being executable by an apparatus and comprising: receiving a repetition of a first DCI and configuration of the repetition of the first DCI; according to the configuration, acquiring a first copy of the first DCI in the first PDCCH candidates allocated to the first CORESET; according to the configuration, obtaining a second copy of a first DCI in a second PDCCH candidate allocated to a second CORESET, wherein the first CORESET and the second CORESET are associated with a first set of search spaces; and obtaining the first DCI from the first and second copies of the first DCI.

In a third aspect of the present application, an apparatus for enhanced PDCCH reception is provided that may perform, by an apparatus comprising a transceiver and a processor, repetition of reception of a first DCI by the transceiver and configuration of the repetition of the first DCI. The processor obtains a first copy of the first DCI in a first PDCCH candidate allocated to a first CORESET according to the configuration, and obtains a second copy of the first DCI in a second PDCCH candidate allocated to a second CORESET according to the configuration. The first CORESET and the second CORESET are associated with a first set of search spaces. The processor obtains the first DCI from the first and second copies of the first DCI.

Brief description of the drawings

In order to more clearly illustrate the embodiments of the present application or related art, the following drawings are described in the embodiments and briefly introduced as follows. It is apparent that the drawings represent only some embodiments of the present application, and that other drawings may be derived by those skilled in the art from these drawings without presetting.

Fig. 1 shows a block diagram of a transmitter for Downlink (DL) or Uplink (UL) transmission.

Fig. 2 shows a block diagram of a receiver for receiving DL or UL transmissions.

Fig. 3 shows a block diagram of a User Equipment (UE) and a base station for enhanced PDCCH transmission and reception according to an embodiment of the present application.

Fig. 4 is a flowchart illustrating a method of enhancing PDCCH transmission according to an embodiment of the present application.

Fig. 5 shows a block diagram of a system for enhanced transmission and reception of PDCCH according to an embodiment of the present application.

Fig. 6 shows a flowchart of a method of enhancing PDCCH transmission according to an embodiment of the present application.

Fig. 7 shows a flowchart of a method of enhancing PDCCH reception according to an embodiment of the present application.

Fig. 8 shows a flowchart of a method of enhancing PDCCH reception according to an embodiment of the present application.

Fig. 9 shows a block diagram of a system for wireless communication according to an embodiment of the application.

Detailed Description

The following describes embodiments of the present application in detail in terms of technical solutions, structural features, achieved objects and effects in combination with the accompanying drawings of the present application. In particular, the terminology used in the embodiments of the application is for the purpose of describing certain embodiments only and is not intended to be limiting of the application.

Fifth generation (5G) wireless systems are typically multi-beam based systems using a frequency range 2 (FR 2) between 24.25GHz and 52.6GHz, wherein Base Stations (BS) and/or User Equipments (UEs) employ multiplexed transmit (Tx) and receive (Rx) analog beams in an attempt to reduce a significant amount of path loss in the high frequency band. In high-band systems such as mmWave systems, the BS and UE configure a large number of antennas, and thus high-gain beamforming techniques can be used to overcome a large number of path losses and signal jammers. Due to hardware limitations and costs, BSs and UEs may be equipped with only a limited number of transmit and receive units (transmission and reception unit, TXRU). Thus, hybrid beamforming mechanisms may be employed in the BS and UE. In order to obtain the best link quality between BS and UE, BS and UE need to align the analog beam directions for specific downlink or uplink transmission. For downlink transmission, the BS and the UE need to find the best pair of BS Tx beam and UE Rx beam, and for uplink transmission, the BS and the UE need to find the best pair of UE Tx beam and BS Rx beam.

For communication between the BS and one UE, the BS and the UE need to determine which one of the Tx beam and the Rx beam is to be used. When one UE moves, the beams used by the BS and the UE for communication may change. Supporting this multi-beam based operation, the following functions are defined in the 3gpp 5g specification.

In operational aspects associated with beam measurement and reporting, in this function, the UE may measure one or more Tx beams of the BS, and then the UE may select and report its selection to the BS. By measuring the Tx beam of the BS, the UE may also measure one or more different Rx beams and then select the best Rx beam for a particular Tx beam of the BS. In this function, the gNB may also measure one or more Tx beams of the UE and then select the best UE Tx beam for uplink transmission. In order to support measurement of the BS's Tx beam, the BS may transmit a plurality of Reference Signal (RS) resources and then configure the UE to measure the RS resources. The UE may then report an index of the selected one or more RS resources based on some measured metrics, e.g., layer 1reference signal received power (Layer 1reference signal received power,L1-RSRP). To support measurement of the Tx beam of the UE for uplink transmission, the BS may configure the UE to transmit one or more uplink RS resources, e.g., sounding reference signal (sounding reference signal, SRS) resources, and then the BS may measure these RS resources. Based on measuring the L1-RSRP, such as RS resources, the BS can clearly know which Tx beam of the UE is most suitable for uplink transmission.

In operational aspects associated with beam indication, for downlink transmissions, the BS may indicate to the UE which Tx beam of the BS to use for transmitting so that the UE may receive the downlink transmission using the appropriate Rx beam. For physical downlink control channel (physical downlink control channel, PDCCH) transmission, the BS may indicate to the UE the Identity (ID) of one BS Tx beam. For physical side downlink discovery channel (physical sidelink discovery channel, PSDCH) transmission, the BS may use downlink control information (downlink control information, DCI) in the PDCCH to indicate an ID of one Tx beam for transmitting a corresponding physical downlink shared channel (physical downlink shared channel, PDSCH). For uplink transmissions from the UE, the BS may also indicate to the UE Tx beam to use. For example, for physical uplink control channel (physical uplink control channel, PUCCH) transmission, the UE uses the Tx beam indicated by the BS through one configuration of the spatial relationship information. For SRS transmission, the UE uses Tx beams indicated by the BS through one configuration of spatial relationship information. For physical uplink shared channel (physical uplink shared channel, PUSCH) transmission, the UE uses the Tx beam indicated by one information element in the scheduling DCI.

In operational aspects associated with beam switching, the BS uses this function to switch Tx beams for downlink or uplink transmissions. This function is advantageous in case that the Tx beam currently used for transmission is outdated due to e.g. movement of the UE. When the BS finds that the Tx beam currently used for downlink transmission is not good, or the BS finds that another Tx beam is better than the current Tx beam, the BS may send signaling to the UE to inform it of the change of the Tx beam. Similarly, the BS may switch to one uplink Tx beam of the UE, which is used to transmit some uplink transmissions.

In a communication system such as a New Radio (NR) system, DL signals may include control signaling for transmitting DCI through a PDCCH, data signals for transmitting information data packets through a PDSCH, and some types of reference signals. The DCI may indicate information of how to transmit the PDSCH including, for example, resource allocation and transmission parameters of the PDSCH. The BS may transmit one or more types of reference signals for different purposes, including demodulation reference symbols (demodulation reference symbol, DM-RS), which are transmitted with the PDSCH and with which the UE may demodulate the PDSCH; channel state information reference signals (channel state information reference signal, CSI-RS) with which the UE may measure BS Tx beams or CSI of a downlink channel between the BS and the UE; and a phase tracking reference signal (phase tracking reference signal, PT-RS), which is also transmitted with the PDSCH and which can be used by the UE to estimate phase noise caused by imperfections in the Radio Frequency (RF) parts of the transmitter and receiver, and then compensate for the PDSCH when decoded. In NR, DL resource allocation of PDCCH, PDSCH, and reference signal is performed in units of orthogonal frequency division multiplexing (orthogonal frequency division multiplexing, OFDM) symbols and a set of physical resource blocks (physical resource block, PRBs). Each PRB contains several Resource Elements (REs) in the frequency domain, for example 12 REs. A transmission Bandwidth (BW) of one downlink transmission is composed of frequency resource units called Resource Blocks (RBs), each RB being composed of a few subcarriers or REs, for example 12 subcarriers or 12 REs.

The UL signal transmitted by the UE to the BS may include a data signal for transmitting a data packet through the PUSCH; an uplink control signal conveying UL control information (UL control information, UCI) which may be transmitted on PUSCH or PUCCH; UL reference signal. UCI may carry a Scheduling Request (SR) with which the UE requests uplink transmission resources, feedback of hybrid automatic repeat request acknowledgement (hybrid automatic repeat request acknowledgement, HARQ-ACK) for PDSCH transmissions, or channel state information (channel state information, CSI) reports. The UE may send one or more types of uplink reference signals for different purposes, including DM-RS, which is sent with PUSCH transmissions and with which the BS may demodulate PUSCH; PT-RS, which is also transmitted with PUSCH transmission and which can be used by the BS to estimate phase noise caused by imperfections in the RF section, and which can then compensate for PUSCH decoding; and SRS signals, which the BS uses to measure one or more UE Tx beams or CSI of an uplink channel between the UE and the BS. Similarly, UL resource allocation for PUSCH, PUCCH, and UL reference signals is also performed in symbol units and a set of PRBs.

The transmission interval of a DL or UL channel/signal is called a slot, each slot containing a few symbols, e.g. 14 symbols, in the time domain. In an NR system, the duration of one slot may be 1, 0.5, 0.25 or 0.123 milliseconds, with subcarrier spacings of 15kHz, 30kHz, 60kHz and 120kHz, respectively. The NR system supports flexible digital proposition (numerology), in one embodiment, an appropriate OFDM subcarrier spacing may be selected according to development scenarios and service requirements. In NR systems, DL and UL transmissions may use different digital propositions.

Fig. 1 shows a block diagram of a transmitter for DL or UL transmissions. The embodiment of the transmitter block shown in fig. 1 is for illustration only. Other embodiments may be used without departing from the scope of the application. The information bits 001 may be encoded first by an encoder 002, such as a low density parity check (low density parity check, LDPC) encoder or a polarity encoder, and then modulated by a modulator 003. This modulation may be, for example, binary phase-shift keying (BPSK), quadrature amplitude modulation (quadrature amplitude modulation, QAM) 4, QAM 16, QAM 64, or QAM 256. Serial-to-parallel (serial to parallel, S/P) converter 004 may then generate a plurality of modulation symbols in parallel, which are then input to RE mapper and precoder 005. The RE mapper and precoder 005 may map the modulation symbols into selected REs and then apply some precoders to the modulation symbols on BW resources allocated for DL or UL transmissions. Then, in 006, the modulation symbols are subjected to an inverse fast fourier transform (inverse fast fourier transform, IFFT), which outputs and then serialized through a parallel-to-serial (parallel to serial, P/S) converter 007. The signal is then sent to a Tx unit 008, which includes, for example, a digital-to-analog (d/a) converter, a radio frequency converter, a filter, power amplification, tx antenna elements, and sent out.

Fig. 2 shows a block diagram of a receiver for receiving DL or UL transmissions. The embodiment of the receiver block shown in fig. 2 is for illustration only. Other embodiments may be used without departing from the scope of the application. The received signal 011 first passes through an Rx unit 012, which includes, for example, an Rx antenna element, a low noise power amplifier, a radio frequency converter, and a filter. And its output passes through P/S013 and then applied to FFT 014. After conversion to the frequency domain, RE demapping 015 extracts the useful signal according to the resource allocation of DL or UL transmission. The demodulated 016 then demodulates the data symbols using channel estimates calculated based on the DM-RS, and then a decoder 017, such as an LDPC decoder or a polar decoder, decodes the demodulated data to output information bits 018.

In release 15 of the NR 3GPP specification, a CORESET may be configured for a UE, in which a set of time-frequency resources for PDCCH transmission is configured. For one CORESET, the UE may be configured with: the CORESET ID, the initial value of the PDCCH DM-RS scrambling, the number of OFDM symbols used by CORESET, which defines the time-frequency resources of the CORESET, and the set of resource blocks, which define the frequency-domain resources of the CORESET. The gNB may also transmit a configuration indicator (transmission configuration indicator, TCI) -state (state) for higher layer parameters for which the UE may use to monitor the DM-RS for the PDCCH to configure an antenna quasi co-location (QCL). For monitoring PDCCH, the gNB may configure a set of search spaces for the UE. In one set of search spaces, the gNB may configure the time-frequency locations where the UE should monitor PDCCH transmissions. In the configuration of the search space set, the gNB may also configure the number of PDCCH candidates and DCI formats of the candidates that the UE is required to expect. Through configuration of the search space set, the gNB may provide the following information to the UE for monitoring the PDCCH:

Index of the slot that may transmit PDCCH;

time-frequency resources in one slot in which PDCCH may be transmitted;

the number of PDCCH candidates per CCE aggregation level; and

DCI formats, which may be transmitted on the PDCCH, e.g., DCI format 0_0 and DCI format 0_1, or DCI format 1_0 and DCI format 1_1.

Fig. 3 illustrates a User Equipment (UE) 10 and a base station 20 for enhanced PDCCH transmission and reception in some embodiments according to an embodiment of the present application. The UE 10 may include a processor 11, a memory 12, and a transceiver 13. The base station 20 may include a processor 21, a memory 22, and a transceiver 23. The processor 11 or 21 may be configured to implement the proposed functions, programs and/or methods described in the present specification. The radio interface protocol layer may be implemented in the processor 11 or 21. The memory 12 or 22 is operatively coupled to the processor 11 or 21 and stores various information to operate the processor 11 or 21. The transceiver 13 or 23 is operatively coupled to the processor 11 or 21, and the transceiver 13 or 23 transmits and/or receives radio signals.

The processor 11 or 21 may include an application-specific integrated circuit (ASIC), other chipset, logic circuit, and/or data processing device. The memory 12 or 22 may include read-only memory (ROM), random-access memory (random access memory, RAM), flash memory, memory cards, storage media, and/or other storage devices. The transceiver 13 or 23 may include a baseband circuit and a Radio Frequency (RF) circuit for processing a radio frequency signal. When the embodiments are implemented in software, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. These modules may be stored in the memory 12 or 22 and executed by the processor 11 or 21. The memory 12 or 22 may be implemented within the processor 11 or 21 or external to the processor 11 or 21, in which case those elements can be communicatively coupled to the processor 11 or 21 via various means as is known in the art.

Referring to fig. 4, in some embodiments, processor 21 is configured to perform a method 600 for enhancing PDCCH transmissions. Processor 21 receives a configuration of a particular DCI format and a configuration of DCI repeatability (block 601). Processor 21 obtains a first DCI for transmission over a PDCCH (block 602) and determines a DCI format for the first DCI (block 603). When the DCI format of the first DCI matches the specific DCI format, processor 21 performs repeated transmission of the first DCI through transceiver 23 (block 604). When the DCI format of the first DCI does not conform to the particular DCI format, processor 21 transmits the first DCI through transceiver 23 without DCI retransmission (block 605). In block 604, processor 21 repeats the transmission of the first DCI through transceiver 23 by transmitting a first copy of the first DCI in a first PDCCH candidate allocated to a first CORESET and transmitting a second copy of the first DCI in a second PDCCH candidate allocated to a second CORESET. The first CORESET and the second CORESET are associated with a first set of search spaces.

The application provides a transmission method of a PDCCH with enhanced reliability. In the present application, a "beam" may correspond to an RS resource, which may be a CSI-RS resource, an SRS resource, a synchronization signal/physical broadcast channel (synchronization signal/physical broadcast channel, SS/PBCH) block, or any other type of RS.

In one embodiment, a UE, such as UE 10, may be configured with one set of search spaces, and the set of search spaces is associated with two or more sets of control resources. PDCCH candidates in those different sets of control resources associated with the same search space are associated. The gNB, e.g., BS 20, may repeat DCIs in concatenated PDCCH candidates of those in different CORESETs disposed in the same search space. On the UE side, during PDCCH detection, the UE may be preset with information of one and the same DCI repeated among PDCCH candidates connected in different cores arranged in the search space. A technical advantage of this proposal is that a multi-TRP system can support transmit diversity for DCI transmission. We can assign different cores associated with the same search space to different TRPs in a multiple TRP system. Those TRPs may send the same copy of one DCI in different cores, and the UE may combine the signals received from multiple TRPs. When the link between one TRP and the UE is blocked, the UE may still successfully detect the PDCCH based on the signal received from the other TRP.

Fig. 5 shows a schematic diagram of an example of a system for enhanced transmission and reception of PDCCH according to an embodiment of the present application.

As shown in FIG. 5, the multi-TRP system 100 has two TRPs, namely TRP-A101 and TRP-B102. TRP-a 101 and TRP-B102 may be separate base stations, each of TRP-a 101 and TRP-B102 being one embodiment of BS 20. Alternatively, TRP-a 101 and TRP-B102 may be separate radio units, but these radio units share a common base station, wherein the common base station is one embodiment of BS 20. UE103 is one embodiment of UE 10. These base stations may be further connected to physical core networks and/or core network slice instances of telecom operators. One example of a UE103 may include UE 10.DCI X140 is an example of first DCI.

In one embodiment of the present application, system 100 may configure a set of search spaces 120 for UE103 to monitor PDCCH transmissions from TRP-a 101 and TRP-B102. The system 100 may configure two CORESETs, CORESET-1 121 and CORESET-2 122, for the UE 103. The system 100 may be a BS or a group of BSs capable of NR transmission. The two CORESETs are associated with a set of search spaces 120 that provide the UE103 with PDCCH monitoring. TRP-a 101 and TRP-B102 may transmit the same DCI X140 on both cores 121 and 122 configured in search space set 120. From the perspective of the UE, the UE may be preset with information to repeatedly transmit the same DCI transmitted in two copies of DCI X140 in PDCCH candidate 131 of CORESET 121 and PDCCH candidate 132 of CORESET 122, the PDCCH candidate 131 and the above-mentioned through higher layer configuration. UE103 may decode PDCCH candidates 131 and 132 separately and if the DCI format of DCI X140 is decoded correctly from either PDCCH candidate, UE103 may declare that the DCI was decoded successfully. UE103 may also combine the received signals from both PDCCH candidates 131 and 132 and then attempt to decode the DCI format of DCI X140 based on the combined signals.

In a first approach, a UE, such as UE 103, may be configured with a first CORESET and a second CORESET, such as CORESETs 121 and 122. For each of the cores, the following parameters may be configured for the UE:

CORESET index p, which is used to identify CORESET;

a DM-RS scrambling sequence initial value used to generate a reference signal sequence for the DM-RS of CORESET;

the number of symbols contained in CORESET, which defines the length of the time domain resources allocated to CORESET;

frequency domain resource allocation to CORESET, which is a set of resource blocks allocated to CORESET in the frequency domain; a method of mapping control channel elements (control channel element, CCE) to resource element groups (resource element group, REG); and

quasi co-location (QCL) configuration of CORESET.

Each CORESET may be configured with a transmission configuration indicator (transmission configuration indicator, TCI) -state (state) that configures one or more reference signal resources to provide a reference for the various quasi-co-sited types of DM-RSs of the CORESET.

The UE may be configured with a first set of search spaces. Both the first CORESET and the second CORESET are associated with a first set of search spaces. For the first set of search spaces, the UE may be configured with one or more of:

An Identifier (ID) of the first set of search spaces, which is used to identify the first set of search spaces;

an association between the first set of search spaces, the first CORESET, and the second CORESET;

configuration of PDCCH monitoring, comprising: k (k) _s PDCCH monitoring periodicity sum o of time slots _s PDCCH monitoring offset of a slot; a PDCCH monitoring pattern within one slot indicating first symbol(s) of CORESET within one slot for PDCCH monitoring; t (T) _s <k _s The duration of the time slot; PDCCH candidates per CCE aggregation level LNumber ofWherein L may be 1,2,4,8 and/or 16;

DCI format that the UE should use to monitor PDCCH candidates in the first set of search spaces; and

the suitability of PDCCH monitoring configuration.

Regarding DCI formats, for example, the UE may be configured to monitor DCI format 0_0 and DCI format 0_1 in the first set of search spaces. Alternatively, for example, the UE may be configured to monitor DCI format 1_0 and DCI format 1_0 in the first set of search spaces. At least one of the plurality of DCI formats may be defined as the specific DCI format. The configuration of DCI repeatability may include at least a portion of all configurations described above.

Regarding the applicability of the PDCCH monitoring configuration, the UE may be pre-configured with the PDCCH monitoring configuration and information of DCI format configurations configured in a first set of search spaces applied to both a first CORESET and a second CORESET, the first CORESET and the second CORESET being associated with the first set of search spaces. The configuration of DCI repeatability may include at least a portion of all configurations described above. The UE may obtain the configuration of DCI repeatability through explicit or implicit signaling from the BS.

For the first search space, in a given time slot n, the UE may be preset with information of PDCCH candidates concatenated together for DCI transmission in the first CORESET and the second CORESET starting from the same first symbol in time slot n. The UE may be preset with information that the same DCI transmits in the concatenated PDCCH candidates. In particular, for a first search space associated with a first CORESET and a second CORESET, at a given time slot of an active DL bandwidth portion (BWP)In the first CORESET and the second CORESET with the same first symbol, the PDCCH candidates in the first CORESET allocated to the aggregation level L +.>And PDCCH candidates in the second CORESET allocated to aggregation level L>Concatenated together for PDCCH detection and monitoring. The UE may be preset with +.for PDCCH candidates>DCI format in CCE carried in the first CORESET and +.>Information of DCI format carried in CCE in second CORESET, said PDCCH candidate +.>DCI of the same content, e.g., DCI x 140, is transmitted.

Fig. 6 shows an example of a gNB 500 that transmits DCI 501 with DCI repeatability in the PDCCH of the first search space. Embodiments of the gNB 500 may include one or more of TRP 101 and TRP 102 in the system 100. DCI 501, e.g. DCI X140, first has CRC bits appended in stage 502, which a receiver UE, e.g. UE 103, can use to detect PDCCH transmission errors. The CRC is then scrambled in stage 503. The RNTI 531 of the UE is used to scramble the CRC portion of the DCI 501. The DCI 501 is then encoded in stage 504, e.g., by polarity encoding. After encoding, the gNB 500 may perform rate matching on the encoded bits of the DCI 501 for the resources in the first CORESET and the second CORESET, respectively. As shown in fig. 6, the rate matching is performed on the encoded bits of the DCI 501 for the resources in the first CORESET in stage 511, and the rate matching is performed on the encoded bits of the DCI 501 for the resources in the second CORESET in stage 521. The rate-matched output bits are then scrambled with a sequence configured in each CORESET at stages 512 and 522. The scrambled output bits are modulated into QPSK symbols at stages 513 and 523. Finally, the gNB 500 may map the modulated symbols and corresponding DM-RS signals to resources in the first CORESET at stage 514 and map the modulated symbols and corresponding DM-RS signals to resources in the second CORESET at stage 524.

In the first approach, concatenated PDCCH candidates transmitting duplicate DCI in those two CORESETs have the same starting symbol and also the same aggregation level. The first approach has the advantage of simplicity of configuration and implementation on the UE side. However, one disadvantage of the first approach is the limited flexibility. In the first method, DCI repetition transmitted by different TRPs must be transmitted at the same CCE aggregation level. In some cases, different TRPs may employ different aggregation levels to transmit the same DCI due to different channel quality and conditions between the TRPs and the UE.

In a second approach, the UE may be configured with a first CORESET and a second CORESET. For each of the cores, the following parameters may be configured for the UE:

a CORESET index for identifying a CORESET;

frequency domain resource allocation to CORESET, defining a set of resource blocks;

a method of mapping CCEs to resource element groups (resource element group, REGs); and

QCL configuration of CORESET, where each CORESET may be configured with a TCI-state that configures one or more reference signal resources to provide references for the various quasi-co-sited types of DM-RSs of CORESET.

Referring to fig. 7, in some embodiments, processor 11 is configured to perform a method 610 for enhancing PDCCH transmission. Processor 11 obtains a configuration of the repeatability of the first DCI, e.g., via transceiver 13 (block 611). The configuration of the repeatability of the first DCI includes a configuration of a specific DCI format. Processor 11 receives a PDCCH transmission including a repetition of the first DCI received via transceiver 13 (block 612) and determines a DCI format of the first DCI (block 613). When the DCI format of the first DCI matches the specific DCI format, processor 11 obtains the first DCI from the first and second copies of the first DCI (block 614). When the DCI format of the first DCI does not coincide with the particular DCI format, processor 11 obtains the first DCI without DCI repetition (block 615).

Referring to FIG. 8, processor 11 is configured to perform a method 620 comprising blocks 621-624, which reveals more details of block 614. Processor 11 obtains a first copy of a first DCI from a first PDCCH candidate allocated to a first set of control resources (control resource set, CORESET) according to the configuration (block 622); according to the configuration, a second copy of the first DCI in a second PDCCH candidate allocated to a second CORESET is obtained (block 623). The first CORESET and the second CORESET are associated with a first set of search spaces. Processor 11 receives a repetition of the first DCI (block 624) and obtains the first DCI from the first and second copies of the first DCI (block 625).

The UE may be configured with a first set of search spaces, and both the first CORESET and the second CORESET are associated with the first set of search spaces. In the configuration of the first set of search spaces, the UE may be configured with (1) a PDCCH monitoring pattern in one slot, i.e., first symbol(s) of CORESET within one slot, for PDCCH monitoring in the first CORESET and PDCCH monitoring in the second CORESET, respectively; (2) Number of PDCCH candidates for one aggregation level of CORESET. The UE may also be configured with a concatenation between the PDCCH candidates in the first CORESET and the PDCCH candidates in the second CORESET to monitor PDCCH repetition. In one embodiment of the invention, for the first set of search spaces, the UE may be configured with one or more of:

time slot position for monitoring PDDCH, which can beTo pass through k _s PDCCH monitoring periodicity sum o of time slots _s PDCCH monitoring offset of a slot to indicate;

·T _s <k _s the duration of a time slot, which represents the presence of a first set of search spaces for a plurality of time slots; and

An association between the first CORESET and the second CORESET within a slot.

For the first CORESET, the UE may be configured with:

PDCCH monitoring pattern within one slot, indicating the first symbol(s) of the first CORESET within one slot; and

the number of PDCCH candidates per CCE aggregation level L of the first CORESET, which may be, for example, 1,2,4,8 and/or 16.

For the second CORESET, the UE may be configured with:

PDCCH monitoring pattern within one slot, indicating the first symbol(s) of the second CORESET within one slot; and

the number of PDCCH candidates per CCE aggregation level L of the second CORESET, which may be, for example, 1,2,4,8 and/or 16.

For the first set of search spaces, the UE may be further configured with an association between the first CORESET and the second CORESET within one slot. For example, the association between the first CORESET and the second CORESET indicates that the PDCCH monitoring indicated by the first symbol a of the first CORESET is associated with the PDCCH monitoring indicated by the first symbol b of the second CORESET. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In one embodiment of the invention, a first symbol indicates a first CORESET and a first symbol indicates a second CORESET within a slot. The PDCCH monitoring in the first CORESET and the PDCCH monitoring in the second CORESET within the same slot are thus associated by the first symbol. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In one embodiment of the invention, more than one first symbol may be configured for a first CORESET within a time slot, and one or more first symbols may be configured for a second CORESET within a time slot. Each first symbol of the second CORESET may be associated with one first symbol of the first CORESET within the same time slot. The UE may be preset with PDCCH in the first CORESET and the second CORESET to monitor information linked through the associated first symbol. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In one embodiment of the invention, one or more starting symbol positions of a first CORESET within a time slot are configured, and one or more starting symbol positions of a second CORESET within a time slot are configured. Within a time slot, an association between one PDCCH monitoring occasion of a first CORESET and one PDCCH monitoring occasion of a second CORESET may be configured based on the one or more starting symbol positions. The configuration of DCI repeatability may include at least a portion of all configurations described above.

For example, two PDCCH monitoring opportunities may be configured for a first CORESET in one slot and one PDCCH monitoring opportunity for a second CORESET in one slot. The first PDCCH monitoring occasion of the second CORESET may be cross-associated with the second PDCCH monitoring occasion of the first CORESET. This association of PDCCH monitoring occasions of the first CORESET and the second CORESET may be used by the gNB to transmit duplicate DCI and may be used by the UE to determine where the duplicate DCI is transmitted.

In one embodiment of the invention, the first symbol(s) of the first CORESET within a slot are configured by a bitmap a0 a1 … aN, with each bit indicating one starting symbol of the PDCCH monitoring occasion of the first CORESET. Also, the first symbol(s) of the second CORESET within a slot are configured by another bitmap b0 b1 … bN, with each bit indicating one starting symbol of the PDCCH monitoring occasion of the second CORESET. The UE may be configured with a third bitmap cN 0c 1..cn that is used to indicate an association between PDCCH monitoring of the second CORESET and PDCCH monitoring of the first CORESET.

Taking n=13 as aN example, for the first CORESET, a0 a1 … an= 10000001000000, and b0 b1 … bn= 01000000000000. Two PDCCH monitoring in one slot are configured to a first CORESET and one PDCCH monitoring in one slot is configured to a second CORESET. The UE may also be configured with c0c … cn=10, which indicates that the PDCCH monitoring of the second CORESET is associated with the PDCCH monitoring of the first CORESET within one slot.

The UE may be configured with a concatenation between PDCCH candidates in PDCCH monitoring of the first CORESET and the second CORESET. The UE may be preset with information that the same DCI is repeated in PDCCH candidates concatenated in the associated PDCCH monitoring of the first CORESET and the second CORESET. The gNB may repeat one DCI transmission in two concatenated PDCCH candidates of the first CORESET and the second CORESET. Also, the UE may be preset with information that may be repeated by one same DCI in the concatenated PDCCH candidates of the first CORESET and the second CORESET. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In a first example, the UE may be preset with information that PDCCH candidates in the first CORESET and the second CORESET are concatenated with each other at the same CCE aggregation level. The UE may be preset with information that one PDCCH candidate in a first core at CCE aggregation level L is concatenated with one PDCCH candidate in a second core at CCE aggregation level L, where L may be 1,2,4,8, or 16. In the case of CCE aggregation level L, the number of PDCCH candidates in the first CORESET is set toThe number of PDCCH candidates in the second CORESET is set to +.>Then, for CCE aggregation level L, PDCCH candidate m in the second CORESET of the first search space set _s PDCCH candidate m in first CORESET with first search space set _s Is connected with-> Is an in-inputAnd->Wherein a function of the minimum is output. In another example, for CCE aggregation level L, the UE may be pre-set with PDCCH candidates m in the second CORESET of the first set of search spaces _s PDCCH candidate in first CORESET with first search space set +.>Information of the link, wherein-> Is->Is a function of (2). And delta is a PDCCH candidate index offset, which may take on values such as 0,1, -1,2, -2,3, -3, or other integers. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In one embodiment of the invention, the first CORESET may be configured as the primary CORESET in the first set of search spaces. While the second CORESET may be configured as a secondary CORESET in the first set of search spaces for providing DCI repetition for DCI transmissions in the first CORESET. The number of PDCCH monitoring occasions of the second CORESET within a slot should not be greater than the number of PDCCH monitoring occasions of the first CORESET. The number of PDCCH candidates for the second CORESET should not be greater than the number of PDCCH candidates for the first CORESET.

In a second example, one PDCCH candidate of a first CORESET at aggregation level L1 may be concatenated with one PDCCH candidate of a second CORESET at aggregation level L2. Here, the CCE aggregation level L1 and the CCE aggregation level L2 may be the same or different. An advantage of this example is that different TRPs may flexibly use different CCE aggregation levels to transmit the same DCI. The path loss between transmission paths from a UE to different TRPs is typically different, so these TRPs may use different CCE levels to send the same DCI to the UE. The configuration of DCI repeatability may include at least a portion of all configurations described above.

In a third example, in the configuration of the first set of search spaces, the UE is configured with a CCE in the first CORESET at CCE aggregation level L1 PDCCH candidate, and the UE is configured with +.The in the second CORESEET at CCE aggregation level L2>PDCCH candidates. In the configuration of the first set of search spaces for the UE, one PDCCH candidate of CCE aggregation level L1 of the first CORESET is concatenated with one PDCCH candidate of CCE aggregation level L2 of the second CORESET, which is also configured for the UE. Then, the UE may be preset with PDCCH candidate m of CCE aggregation level L2 in the second CORESET _s PDCCH candidate m with CCE aggregation level L1 in first CORESET in first search space set _s And information of the connection. In another example, the UE may be pre-set with PDCCH candidate m of CCE aggregation level L2 in the second CORESET _s PDCCH candidate +.f. for CCE aggregation level L1 in first CORESET in first search space set>And information of the connection. The configuration of DCI repeatability may include at least a portion of all configurations described above.

Table one shows an example of a computer executable program for configuring a set of search spaces associated with two CORESETs for DCI repetition in accordance with the present application.

List one

In one approach, the UE may be requested to preset information that only one particular DCI format is repeated in the first CORESET and the second CORESET associated with the first set of search spaces. This approach is beneficial to reduce the complexity of UE implementation. Another technical motivation for this approach is that DCI repetition is typically advantageous for ultra-reliable low-latency communication (URLLC) services, and PDSCH transmissions at URLLC services may be scheduled by a specific DCI format. Thus, for DCI repetition, it is sufficient that the UE monitors only a specific DCI format.

In the configuration of the first set of search spaces, the UE may be configured with a higher layer parameter indicating a DCI format without DCI repetition, when the UE should expect decoding in a PDCCH candidate in the first CORESET, and another higher layer parameter indicating a DCI format with DCI repetition, when the UE may expect decoding in a concatenated PDCCH candidate in the first CORESET and the second CORESET.

The multi-TRP system according to the embodiment of the present application may repeat transmission of one same DCI from a plurality of TRPs to a single UE. Transmission diversity of the PDCCH from a plurality of TRPs is achieved, and thus the reliability of PDCCH transmission is improved. An important use case of the multi-TRP system according to the embodiment of the present application is the URLLC service having strict requirements on the performance of both PDCCH and PDSCH channels.

Fig. 9 is a block diagram of a system 700 for wireless communication according to an embodiment of the present application. The embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. For example, each of UE10 and UE103 may be implemented as system 700. Fig. 9 shows a system 700, the system 700 comprising Radio Frequency (RF) circuitry 710, baseband circuitry 720, application circuitry 730, memory/storage 740, display 750, camera 760, sensor 770, and input/output (I/O) interface 780 coupled to one another at least as shown.

Application circuitry 730 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. A processor may include any combination of general-purpose and special-purpose processors (e.g., graphics processors and application processors). The processor may be coupled with the memory/storage device and configured to execute instructions stored in the memory/storage device to enable various application programs and/or an operating system to run on the system.

Baseband circuitry 720 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may comprise a baseband processor. The baseband circuitry may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry. Radio control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, and the like. In some embodiments, the baseband circuitry may provide communications compatible with one or more wireless technologies. For example, in some embodiments, the baseband circuitry may support communication with an Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or other Wireless Metropolitan Area Networks (WMANs), wireless Local Area Networks (WLANs), wireless Personal Area Networks (WPANs). An embodiment in which the baseband circuitry is configured to support wireless communications for more than one wireless protocol may be referred to as a multi-mode baseband circuitry. In various embodiments, baseband circuitry 720 may include circuitry to operate with signals that are not strictly considered to be in baseband frequency. For example, in some embodiments, the baseband circuitry may include circuitry to operate with signals having an intermediate frequency between the baseband frequency and the radio frequency.

RF circuitry 710 may use modulated electromagnetic radiation to enable communication with a wireless network through a non-solid medium. In various embodiments, the RF circuitry may include switches, filters, amplifiers, and the like to facilitate communication with the wireless network. In various embodiments, RF circuitry 710 may include circuitry for operating with signals that are not strictly considered to be at radio frequencies. For example, in some embodiments, the RF circuitry may include circuitry for operating with signals having an intermediate frequency between baseband and radio frequencies.

In various embodiments, the transmitter circuitry, control circuitry, or receiver circuitry discussed above with respect to the user equipment, eNB, or gNB may be implemented, in whole or in part, in one or more of RF circuitry, baseband circuitry, and/or application circuitry. As used herein, "circuitry" may refer to, be part of, or include the following: an Application Specific Integrated Circuit (ASIC), an electronic circuit executing one or more software or firmware programs, a processor and/or memory (shared, dedicated, or group), a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the electronic device circuitry may be implemented in or the functionality associated with one or more software or firmware modules. In some embodiments, some or all of the constituent components of the baseband circuitry, application circuitry, and/or memory/storage may be implemented together on a system on a chip (SOC).

Memory/storage 740 may be used to load and store data and/or instructions, for example, for the system. The memory/storage of an embodiment may include any combination of suitable volatile memory (e.g., dynamic Random Access Memory (DRAM)) and/or non-volatile memory (e.g., flash memory). In various embodiments, the I/O interface 780 may include one or more user interfaces designed to enable a user to interact with the system and/or peripheral component interfaces designed to enable peripheral components to interact with the system. The user interface may include, but is not limited to, a physical keyboard or keypad, a touchpad, a speaker, a microphone, and the like. Peripheral component interfaces may include, but are not limited to, non-volatile memory ports, universal Serial Bus (USB) ports, audio jacks, and power interfaces.

In various embodiments, the sensor 770 may comprise one or more sensing devices for determining environmental conditions and/or location information related to the system. In some embodiments, the sensors may include, but are not limited to, gyroscopic sensors, accelerometers, proximity sensors, ambient light sensors, and positioning units. The positioning unit may also be part of or interact with baseband circuitry and/or RF circuitry to communicate with components of a positioning network, such as Global Positioning System (GPS) satellites. In various embodiments, display 750 may include displays such as liquid crystal displays and touch screen displays. In various embodiments, system 700 may be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, a superbook, a smartphone, and the like. In various embodiments, the system may have more or fewer components and/or different architectures. The methods described herein may be implemented as computer programs, where appropriate. The computer program may be stored on a storage medium such as a non-transitory storage medium.

The embodiment of the application provides a method and a device for enhancing PDCCH transmission, which can improve reliability. Embodiments of the present application are a combination of techniques/procedures that may be employed in 3GPP specifications to develop end products.

Those of ordinary skill in the art will appreciate that each of the units, algorithms, and steps described and disclosed in the embodiments of the disclosure are implemented using electronic hardware, or a combination of software and electronic hardware for a computer. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the particular implementation. Those of ordinary skill in the art may implement the functionality of each particular application in different ways without departing from the scope of the application. It will be appreciated by those of ordinary skill in the art that reference may be made to the operation of the systems, devices and units of the above embodiments, as the operation of the systems, devices and units are substantially identical. For ease of description and brevity, these operations will not be described in detail.

It should be understood that the systems, devices, and methods disclosed in the embodiments of the present disclosure may be implemented in other ways. The embodiments described above are merely illustrative. The partitioning of the cells is based solely on logic functions, while other partitions exist when implemented. Multiple units or components may be combined or may be integrated into another system. Some features may be omitted or skipped. On the other hand, the mutual coupling, direct coupling or communicative coupling shown or discussed may be indirect coupling or electrical, mechanical or other form of communicative coupling via some interfaces, devices or units.

The units described as separate components may or may not be physically separate. The units shown may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be used according to the purpose of the embodiment. In addition, each functional unit in each embodiment may be integrated in one processing unit, may be physically independent, or may be integrated in one processing unit.

If the software functional unit is implemented and sold or used as a stand-alone product, it may be stored in a readable storage medium in a computer. Based on such understanding, the solution proposed by the present application may be implemented essentially or partly in the form of a software product. Alternatively, a part of the technical solutions beneficial to the prior art may be implemented in the form of a software product. The software product in the computer is stored in a storage medium, including a plurality of commands for a computing device (e.g., a personal computer, server, or network device) to execute all or part of the steps disclosed by embodiments of the present disclosure. The storage medium includes a USB disk, a removable hard disk, a read-only memory (ROM), a random-access memory (RAM), a floppy disk, or other medium capable of storing program code.

While the application has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the application is not to be limited to the disclosed embodiment, but is intended to cover various arrangements included within the scope of the appended claims without departing from the broadest interpretation of the claims.

Claims

1. A method of enhancing physical downlink control channel, PDCCH, transmission, the method being executable by an apparatus and comprising:

repeating transmission of a first control resource set CORESET by transmitting a first copy of a first downlink control information, DCI, in a first PDCCH candidate allocated to the first DCI and transmitting a second copy of the first DCI in a second PDCCH candidate allocated to a second CORESET, wherein the first CORESET and the second CORESET are associated with a first set of search spaces;

is configured with a third association between the first PDCCH candidate and the second PDCCH candidate, wherein the third association represents a first control channel element CCE aggregation level L ₁ Is associated with a second CCE aggregation level L ₂ The second PDCCH candidate of (c), and the L ₁ Different from the L ₂ ；

Wherein the second PDCCH candidate index is the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s The first PDCCH candidate index is the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in (1)The third association represents the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s Associated with the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in-> Is->And the delta is a PDCCH candidate index offset, the number of PDCCH candidates in the first CORESET is set to +.>

2. The method of claim 1, further comprising:

receiving a configuration of a specific DCI format;

determining a DCI format of the first DCI; and

and when the DCI format of the first DCI accords with the specific DCI format, performing repeated transmission of the first DCI.

3. The method of claim 1, further comprising being configured with a first association between a first and a second copy of the first DCI, wherein the first association represents that the first copy in a first control channel element, CCE, aggregation level used to detect the PDCCH candidate in the first CORESET transmitted from a first transmission receiving node, TRP, is associated with the second copy in a second CCE aggregation level used to detect the second PDCCH candidate in the second CORESET transmitted from a second TRP.

4. The method of any of claims 1 and 3, further comprising being configured with a second association between the first PDCCH candidate and the second PDCCH candidate, wherein the second association represents a first CCE aggregation level L ₁ Is associated with a second CCE aggregation level L ₂ The second PDCCH candidate of (c), and the L ₁ Identical to said L ₂ 。

5. The method of claim 4, wherein the second PDCCH candidate index is the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s The first PDCCH candidate index is the CCE aggregation level L in the first CORESET ₁ PDCCH candidate m in (2) _s The second association represents the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s Associated with the CCE aggregation level L in the first CORESET _l PDCCH candidate m in (2) _s 。

6. The method of claim 4, wherein the second PDCCH candidate index is the second PDCCH candidate indexCCE aggregation level L as described in CORESET ₂ PDCCH candidate m in (2) _s The first PDCCH candidate index is the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in (1)The second association represents the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s Associated with the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in (1)Is->And the delta is a PDCCH candidate index offset.

7. The method of claim 1, further comprising being configured with a fourth association between the first CORESET and the second CORESET, wherein the fourth association represents that a first symbol of the first CORESET is associated with a first symbol of the second CORESET.

8. A method of enhancing physical downlink control channel, PDCCH, reception, the method being executable by an apparatus and comprising:

receiving a repetition of first Downlink Control Information (DCI) and a configuration of the repetition of the first DCI;

according to the configuration, acquiring a first copy of the first DCI in the first PDCCH candidates allocated to the first control resource set CORESET;

according to the configuration, obtaining a second copy of a first DCI in a second PDCCH candidate allocated to a second CORESET, wherein the first CORESET and the second CORESET are associated with a first set of search spaces;

obtaining the first DCI from the first and second copies of the first DCI;

is configured with the first PDCCH candidate and the second PDC A third association between CH candidates, wherein the third association represents a first control channel element CCE aggregation level L ₁ Is associated with a second CCE aggregation level L ₂ The second PDCCH candidate of (c), and the L ₁ Different from the L ₂ ；

9. The method of claim 8, further comprising:

receiving a configuration of a specific DCI format;

determining a DCI format of the first DCI; and

when the DCI format of the first DCI matches the specific DCI format, the first DCI is acquired from the first and second copies of the first DCI.

10. The method of claim 8, further comprising being configured with a first association between a first and a second copy of the first DCI, wherein the first association represents that the first copy in a first control channel element, CCE, aggregation level used to detect the PDCCH candidate in the first CORESET transmitted from a first transmission receiving node, TRP, is associated with the second copy in a second CCE aggregation level used to detect the second PDCCH candidate in the second CORESET transmitted from a second TRP.

11. The method of any of claims 8 and 10, further comprising being configured with a second association between the first PDCCH candidate and the second PDCCH candidate, wherein the second association represents a first CCE aggregation level L ₁ Is associated with a second CCE aggregation level L ₂ The second PDCCH candidate of (c), and the L ₁ Identical to said L ₂ 。

12. The method of claim 11, wherein the second PDCCH candidate index is the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s The first PDCCH candidate index is the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in (1)The second association represents the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s Associated with the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in->Is->And the delta is a PDCCH candidate index offset.

13. The method of claim 8, further comprising being configured with a fourth association between the first CORESET and the second CORESET, wherein the fourth association represents that a first symbol of the first CORESET is associated with a first symbol of the second CORESET.

14. An apparatus that enhances physical downlink control channel, PDCCH, reception, which is executable by an apparatus and comprises:

A transceiver for receiving a repetition of a first downlink control information, DCI, and a configuration of the repetition of the first DCI; and

a processor configured to obtain a first copy of the first DCI allocated to a first PDCCH candidate of a first set of control resources CORESET according to the configuration and a second copy of the first DCI allocated to a second PDCCH candidate of a second CORESET according to the configuration, wherein the first CORESET and the second CORESET are associated with a first set of search spaces, wherein the processor is configured to obtain the first DCI from the first copy and the second copy of the first DCI and is configured with a third association between the first PDCCH candidate and the second PDCCH candidate, wherein the third association represents a first control channel element aggregation level L ₁ Is associated with a second CCE aggregation level L ₂ The second PDCCH candidate of (c), and the L ₁ Different from the L ₂ Wherein the second PDCCH candidate index is the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s The first PDCCH candidate index is the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in (1)The third association represents the CCE aggregation level L in the second CORESET ₂ PDCCH candidate m in (2) _s Associated with the CCE aggregation level L in the first CORESET ₁ PDCCH candidates in->Is->And the delta is a PDCCH candidate index offset, the number of PDCCH candidates in the first CORESET is set to +.>