CN114223294A

CN114223294A - Phased signal detection

Info

Publication number: CN114223294A
Application number: CN201980099367.4A
Authority: CN
Inventors: 刘建国; 陶涛; K·肖伯; E·蒂罗拉
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy
Priority date: 2019-08-16
Filing date: 2019-08-16
Publication date: 2022-03-22
Also published as: WO2021031006A1

Abstract

Example embodiments of the present disclosure relate to an apparatus, method, device, and computer-readable storage medium for phased signal detection in a frame period. In an example embodiment, a first device performs detection of a first signal from a second device in at least a first set of search spaces within a frame period. The first device determines whether a first signal is detected in at least a first set of search spaces within a frame period. The first device performs detection of a second signal from a second device in at least a second set of search spaces associated with the first set of search spaces within the frame period if it is determined that the first signal is detected in the at least first set of search spaces.

Description

Phased signal detection

Technical Field

Embodiments of the present disclosure relate to the field of communications, and in particular, to an apparatus, method, device, and computer-readable storage medium for phased signal detection in a frame period.

Background

New Radio (NR) based access to unlicensed spectrum is specified in third generation partnership project (3GPP) standardization. In unlicensed NR (NR-U), a frame-based device (FBE) is provided with fixed timing for transmission and reception over the unlicensed spectrum. FBEs may include both network devices, such as base stations, and terminal devices, such as User Equipment (UE).

FBE operation needs to be consistent with regulatory requirements. According to European Telecommunications Standards Institute (ETSI) Broadband Radio Access Network (BRAN) regulations, FBEs need to implement Listen Before Talk (LBT) based Clear Channel Assessment (CCA) to detect the presence of other Radio Local Access Network (RLAN) transmissions on an operating channel. Currently, a Frame Structure (FS) based on FBE is being developed.

Disclosure of Invention

In general, example embodiments of the present disclosure provide an apparatus, method, device, and computer-readable storage medium for phased signal detection in a frame period.

In a first aspect, a first apparatus is provided that includes at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to perform detection of a first signal from a second device in at least a first set of search spaces within a frame period. The first device is caused to determine whether a first signal is detected in at least a first set of search spaces within a frame period. The first device is further caused to perform, in response to determining that the first signal is detected in at least the first set of search spaces, detection of a second signal from a second device within at least a second set of search spaces associated with the first set of search spaces within the frame period.

In a second aspect, a method is provided. In the method, a first device performs detection of a first signal from a second device in at least a first set of search spaces within a frame period. The first device determines whether a first signal is detected in at least a first set of search spaces within a frame period. The first device performs detection of a second signal from a second device in at least a second set of search spaces associated with the first set of search spaces within the frame period if it is determined that the first signal is detected in the at least first set of search spaces.

In a third aspect, an apparatus is provided that comprises means for performing the method according to the second aspect.

In a fourth aspect, a computer-readable storage medium is provided that includes program instructions stored thereon. The instructions, when executed by a processor of a device, cause the device to perform a method according to the second aspect.

It should be understood that the summary is not intended to identify key or essential features of the example embodiments of the disclosure, nor is it intended to be used to limit the scope of the disclosure. Other features of the present disclosure will become readily apparent from the following description.

Drawings

Some example embodiments will now be described with reference to the accompanying drawings, in which:

FIG. 1 illustrates a conventional FBE frame;

fig. 2 illustrates a conventional FBE-based Frame Structure (FS);

FIG. 3 illustrates an example environment in which example embodiments of the present disclosure may be implemented;

fig. 4 shows a flow diagram of an example method according to some example embodiments of the present disclosure;

fig. 5 illustrates an example SS set configuration within a frame period, in accordance with some example embodiments of the present disclosure;

fig. 6 illustrates an example SS set configuration over two consecutive frame periods, in accordance with some example embodiments of the present disclosure; and

fig. 7 shows a simplified block diagram of a device suitable for implementing an example embodiment of the present disclosure.

Throughout the drawings, the same or similar reference numbers refer to the same or similar elements.

Detailed Description

The principles of the present disclosure will now be described with reference to a few exemplary embodiments. It is understood that these exemplary embodiments are described merely to illustrate and assist those of ordinary skill in the art in understanding and enabling the disclosure, and do not imply any limitation on the scope of the disclosure. The disclosure described herein may be implemented in various ways other than those described below.

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

As used herein, the term "terminal device" or "user equipment" (UE) refers to any terminal device capable of wireless communication with each other or a base station. Communication may involve the transmission and/or reception of wireless signals using electromagnetic signals, radio waves, infrared signals, and/or other types of signals suitable for the transmission of information over the air. In some example embodiments, the UE may be configured to transmit and/or receive information without direct human-machine interaction. For example, the UE may transmit information to the base station according to a predetermined schedule, triggered by an internal or external event, or in response to a request from the network side.

Examples of UEs include, but are not limited to, smart phones, wireless enabled tablets, laptop embedded devices (LEEs), laptop installed devices (LMEs), wireless client devices (CPEs), sensors, metering devices, personal wearable devices such as watches, and/or communication enabled vehicles. For purposes of discussion, some example embodiments will be described with reference to a UE as an example of a terminal device, and the terms "terminal device" and "user equipment" (UE) may be used interchangeably in the context of this disclosure. The UE may also correspond to a Mobile Terminal (MT) part of an Integrated Access and Backhaul (IAB) node (also referred to as a relay node).

As used herein, the term "network device" refers to a device via which services may be provided to terminal devices in a communication network. As an example, the network device may include a base station. As used herein, the term "base station" (BS) refers to a network device via which services may be provided to terminal devices in a communication network. A base station may comprise any suitable device via which a terminal device or UE may access a communication network. Examples of base stations include relays, Access Points (APs), transmission points (TRPs), node bs (NodeB or NB), evolved NodeB (eNodeB or eNB), New Radio (NR) NodeB (gnb), remote radio modules (RRUs), Radio Heads (RH), Remote Radio Heads (RRHs), low power nodes such as femto, pico, etc. The relay node may correspond to a Distributed Unit (DU) portion of the IAB node.

As used herein, the term "search space set" (set of SSs) refers to a set of time domain resources or locations for a receiver to monitor or detect signals from a transmitter. The receiver may be implemented by a terminal device or a network device, and the transmitter may be implemented by a terminal device or a network device. In some example embodiments, the search space set indicates all possible locations of a Physical Downlink Control Channel (PDCCH) for detection by the terminal device. Each search space may be associated with a CORESET (control resource set), which may define, for example, resource elements (such as OFDM symbols, subcarriers) that may be used for the associated search space set.

As used herein, the term "circuitry" may refer to one or more or all of the following:

(a) a purely hardware circuit implementation (such as an implementation using only analog and/or digital circuitry), and

(b) a combination of hardware circuitry and software, such as (as applicable): (i) a combination of analog and/or digital hardware circuit(s) and software/firmware, and (ii) a hardware processor(s) with software (including a digital signal processor), software, and any portion of memory(s) that cooperate to cause an apparatus (such as a mobile phone or server) to perform various functions, and

(c) hardware circuit(s) and/or processor(s), such as microprocessor(s) or a portion of microprocessor(s), that require software (e.g., firmware) for operation, but software may not be present when operation is not required.

The definition of circuitry applies to all uses of the term in this application, including in any claims. As another example, as used in this application, the term circuitry also encompasses implementations of only a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. For example, the term circuitry, if applicable to a particular claim element, also encompasses a baseband integrated circuit or processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular base station, or other computing or base station.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "include" and its variants should be understood as open-ended terms meaning "including, but not limited to". The term "based on" should be understood as "based at least in part on". The terms "one embodiment" and "an embodiment" should be understood as "at least one embodiment". The term "another embodiment" should be understood as "at least one other embodiment". Other definitions (explicit and implicit) may be included below.

As used herein, the terms "first," "second," and the like may be used herein to describe various elements, which should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term "and/or" includes any and all combinations of one or more of the listed terms.

As specified, the FBE needs to perform LBT to detect the presence of other RLAN transmissions on the operating channel in a Fixed Frame Period (FFP). Fig. 1 shows an example FBE frame 100. In this example, two consecutive FFPs 105-1 and 105-2 (collectively referred to as FFPs 105 or individually as FFPs 105) are shown. It should be understood that detection may be performed in any suitable number of FFPs.

An initiating device (terminal device or network device) may occupy the channel at the beginning of FFP105 after a single LBT-based CCA 120 and initiate a transmission from the beginning of FFP 105. Within the FFP105, an initiating device may perform multiple communications in different directions. In the case where the initiating device is a network device, the initiating device may authorize one or more associated responding devices (such as terminal devices) to transmit on the current operating channel within the current FFP 105. The operation through the FBE framework has a periodic timing with a period equal to FFP 105.

FFP105 may be in the range of 1 to 10ms, and FFP105 may change no more than once every 200ms, according to ETSI regulatory requirements. Further, as shown, it is required that within each FFP105, the Channel Occupancy Time (COT)110 acquired by the initiating device is no greater than 95% of the FFP 105. At the end of each FFP105, there remains an idle period 115, the idle period 115 being no less than 5% of the FFP105, for a minimum of 100 μ s.

Fig. 2 illustrates an exemplary FBE-based FS 200, which may be followed by an NR node B (or gNB) operating on a 5GHz unlicensed band. Example configurations of FBE-based FS 200 are shown in table 1.

TABLE 1

FFP(ms)	4
		Subcarrier spacing (SCS) (kHz)	30
Number of slots per subframe	2
		Number of slots per FFP	8
Number of slots in COT (95%)	7.6
		Number of complete slots in COT	7
Number of available symbols of last slot	8.4
		Number of available complete symbols of last slot	8
Number of Guard Period (GP) symbols in idle period (5%)	6

As shown, in the FBE-based FS 200, the FFP105 is 4ms and includes 8 slots 205 of 0.5ms, and each slot 205 includes 14 symbols 210. With 95% of the FFP105 configured as the COT 110, the COT 110 occupies 7 full slots 205 and 8 full symbols 210 of the last slot 205, and the idle period 115 occupies 6 symbols 210 of the last slot 205.

In NR networks, FBE-based FS may be indicated to the UE by the gNB through parameters such as the offset and periodicity of FFP, e.g., by using higher layer signaling such as System Information Blocks (SIBs) or layer 1 (L1) signaling such as Dedicated Control Information (DCI).

For NR-U, it is agreed to benchmark FBE operation in a specification, such as the ETSI BRAN specification. If the gNB acts as the initiating device and the UE acts as the responding device as defined in the ETSI rules, the gNB may acquire the COT by performing a single LBT and all Downlink (DL) and Uplink (UL) transmissions may be transmitted within the COT acquired by the gNB.

In NR-U specifications such as 3GPP TR 38.889, FBE operation is specified to include the following:

the gNB acquires COT for class 2(Cat 2) immediately before FFP.

Within the COT acquired by the gNB, the gNB and associated UE may use class 1(Cat 1) if the handover gap from receiving the transmission does not exceed 16 us.

Within the COT acquired by gNB, if the handover gap is greater than 16us, then gNB and associated UE should use Cat 2.

Typically, in Licensed Assisted Access (LAA) for Long Term Evolution (LTE) unlicensed (LTE-U), the UE monitors the DL control channel at the slot boundaries (twice in a 1ms subframe, e.g., with a 30kHz subcarrier spacing) to enable the base station to start COT with 0.5ms granularity without using a reservation signal. Currently, there are exceptions to NR-U, i.e., gNB can use the more frequent COT start position. For example, according to the 3GPP specifications, the gNB may use a 30kHz subcarrier spacing (SCS) and a maximum of 7 starting positions within one slot (i.e., one starting position of 1/14ms each).

In terms of spectrum utilization, higher SCS or shorter slot duration and more starting positions within the slot may allow the gNB to access the available channels faster and thus achieve higher transmission efficiency by minimizing the transmission of the reservation signal. On the other hand, the UE needs to monitor the DL control channel more frequently. However, monitoring of the DL control channel is power consuming. Furthermore, in fact, a large amount of control channel decoding occurs in subframes or slots in which the UE does not receive a grant or schedule, since the gNB may not even be able to access the channel due to LBT failure. It is desirable to reduce UE complexity (and power consumption) by reducing DL bursts or PDCCH monitoring when not needed.

Several approaches for saving UE power in DL burst monitoring have been discussed for transmitting and receiving load-based devices (LBEs) with demand-driven (but not fixed) timing over unlicensed spectrum. One approach is to use Wi-Fi as a preamble. By detecting the preamble at the beginning of a subframe or slot, the UE can determine whether the channel is acquired by the base station. Another approach is based on wideband demodulation reference signals (DMRS) in NR-U. However, the UE still needs to constantly monitor DL bursts outside the COT.

For LBE-based NR-U, it is proposed to monitor the adaptation between three phases, referred to as phase a, phase B and phase C. Phase a is outside the channel occupancy of the gNB, where the UE can determine the presence of DL transmissions by the gNB. Phase B is the beginning of the channel occupancy (e.g., initial slot) by the gNB. Phase C is in the remainder of the channel occupancy of the gNB (e.g., other time slots than the initial time slot). For example, 3GPP specifications, such as 3GPP TR 38.889, allow for dynamic changes in the time domain time instance in which a UE is expected to receive a Physical Downlink Control Channel (PDCCH), modifications to achieve gapless Discovery Reference Signal (DRS) transmission in the time domain, and indications of the time domain COT structure.

To dynamically switch Blind Decoding (BD) operation, different PDCCH monitoring configurations are allowed. The UE may switch between two PDCCH configurations (for more and less frequent detection) at the first and last slot boundaries of the COT. The UE may determine the particular monitoring configuration to apply from an explicit indication, e.g., by DCI, or an implicit indication based on a relationship to the detected start of a window of DL bursts or configurations. The following proposals are being discussed to enable a UE to change the monitoring behavior of a PDCCH or a group common PDCCH (GC-PDCCH) where the monitoring behavior may occur, based on a control resource set (CORESET) and search space parameters:

indication, e.g. by DCI content or DCI Cyclic Redundancy Check (CRC) pass

Indication of past performance

Correlation with detection of DL bursts, including:

before and after the end of the first (or initial) time slot of the detected burst

Before and after the end of the DL burst

Timer after DCI detection

End of DL burst

Timer after DCI detection

Based on the configuration

However, for UE-based LBE, frequent monitoring may be performed despite no DL transmission in FFP, even if it is useless. The inventors note that in scenarios where there is no LBE-based device, FBE operation may reduce UE monitoring complexity for detecting DL transmissions based on characteristics of FBE-based FS in NR-U. For example, as described above, in accordance with regulatory requirements, an initiating device (e.g., a gNB) can only occupy a channel at the beginning of FFP for a single LBT, and transmissions may be initiated at the beginning of FFP. This means that if the gNB does not acquire the channel at the start of the FFP, it will not initiate any transmission in the FFP, including DL burst transmissions.

Example embodiments of the present disclosure provide a phased monitoring scheme based on a novel search space design in a frame period (e.g., FFP). The scheme defines search space dependencies between different types of Sets of Search Spaces (SSs) within a frame period. With this scheme, at least two different types of SS sets are configured to have dependency within one frame period. Different types of sets of SSs may be configured with different monitoring granularity or periodicity. One type of SS set is first monitored in a frame period. If a signal is detected in at least one set of SSs of this type within a frame period, signal detection is initiated in another set of SSs of the type associated with the at least one set of SSs within the frame period.

For ease of discussion, in some example embodiments, the first detected set of SSs is referred to as an independent set of SSs, and the second detected set of SSs is referred to as a dependent set of SSs. For example, in a scenario in which the UE detects the start of a COT acquired by the gNB, the UE may first perform blind detection of the start of the COT from the start of a frame period (e.g., FFP) in at least one independent set of SSs. If the start of the COT is detected in one of the independent sets of SSs, the UE starts monitoring in the subordinate set of SSs associated with the independent set of SSs until the end of the COT within the frame period. If the UE detects that the gNB does not acquire the channel at the beginning of the frame period within the monitoring opportunity of the independent SS, the UE may stop monitoring the DL transmission, which may be beneficial to reducing monitoring complexity and power consumption at the UE.

FIG. 3 illustrates an example environment 300 in which example embodiments of the present disclosure may be implemented. The environment 300, which may be part of a communication network, includes two

devices

310 and 320, the two

devices

310 and 320 being referred to as a first device 310 and a second device 320, respectively, and may communicate with each other or with other devices via each other.

The first device 310 and the second device 320 may be implemented by any suitable device in a communication network. In some example embodiments, the first device 310 may be implemented by a terminal device and the second device 320 may be implemented by a network device, or vice versa. In some other example embodiments, both the first device 310 and the second device 320 may be implemented by terminal devices or network devices. For discussion purposes only, in some example embodiments, a terminal device will be taken as an example of the first device 310 and a network device will be taken as an example of the second device 320.

It should be understood that two devices are shown in environment 300 for illustrative purposes only and do not imply any limitation on the scope of the present disclosure. Any suitable number of devices, including network devices or terminal devices, may be included in environment 300.

The communication may follow any suitable communication standard or protocol that already exists or will be developed in the future, such as Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), LTE-advanced (LTE-a), fifth generation (5G) New Radio (NR), wireless fidelity (Wi-Fi), and Worldwide Interoperability for Microwave Access (WiMAX) standards, and employ any suitable communication technology including, for example, Multiple Input Multiple Output (MIMO), Orthogonal Frequency Division Multiplexing (OFDM), Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), Code Division Multiplexing (CDM), Bluetooth, ZigBee, and Machine Type Communication (MTC), enhanced mobile broadband (eMBB), mass Machine Type Communication (MTC), ultra-reliable low delay communication (URLLC), Carrier Aggregation (CA), Dual Connectivity (DC), and new radio unlicensed (NR-U) technologies.

The first device 310 and the second device 320 may operate on the unlicensed spectrum and/or the licensed spectrum. In various example embodiments, the first device 310 and the second device 320 may communicate within a frame period. The frame period may be fixed, such as the FFP105 shown in fig. 1 and 2. The frame period may also be dynamically configurable.

At least two types of SS sets (including independent SS sets and dependent SS sets) are configured for communication between the first device 310 and the second device 320 in a frame period. The first device 310 first detects a signal from the second device 320 in one or more independent sets of SSs within a frame period. If a signal is detected in at least one of the independent sets of SSs, the first device 310 detects another signal from the second device 320 in one or more of the dependent sets of SSs associated with the at least one independent set of SSs during the frame period. If no signal is detected, the first device 310 will not initiate monitoring in any of the slave SS sets until the next monitoring occasion in the independent SS set and further until the next frame period. In this way, the first device 310 conditionally monitors the dependent SS set(s) based on the monitoring output in the independent SS set(s), which would facilitate UE monitoring complexity reduction and power saving.

Fig. 4 illustrates a flow diagram of an example method 400 in accordance with some example embodiments of the present disclosure. The method 400 may be implemented by the first device 310 shown in fig. 3. For discussion purposes, the method 400 will be described with reference to fig. 3.

At block 405, the first device 310 performs detection of a signal (referred to as a first signal) from the second device 320 in at least one set of SSs (referred to as a first set of SSs) within a frame period. The first set of SSs may be an independent set of SSs or a dependent set of SSs to be depended on by further dependent sets of SSs. The frame period may be fixed in timing, such as the FFP105 shown in fig. 1 and 2. Alternatively or additionally, the frame period may be dynamically or semi-statically configured. The UE may also be configured with multiple sets of SSs associated with different fixed frame periods. For example, one set of SSs may be associated with an FFP of 8ms, while another set of SSs may be associated with an FFP of 2ms, respectively.

The first signal may comprise any suitable signal transmitted over an unlicensed or licensed spectrum (or frequency band). In some example embodiments, the first signal may indicate that the channel is occupied by the second device 320 on the unlicensed spectrum, for example. For example, the first signal may indicate the start of a COT acquired by the second device 320.

The first signal may comprise unicast or broadcast signaling, or be in the form of a sequence. As an example, the first signal may include a signal transmitted on a PDCCH or a GC-PDCCH. As another example, the first signal may include a sequence such as a wideband DMRS (WB-DMRS) and Wi-Fi such as a preamble to further reduce power consumption of the first device 310. The first signal may further include a signal transmitted on the PDCCH and the GC-PDCCH. In another example, the first signal may be a combination of a WB-DMRS sequence and a signal transmitted on a PDCCH.

The detection of the first signal may include blind detection in at least the first set of SSs during the frame period. In addition to the first set of SSs, the first device 310 may perform detection of the first signal in other sets of SSs within the frame period. It is also possible to configure only the first set of SSs within the frame period. In this case, the first device 310 centrally monitors the first SS for the first signal from the second device 320 only for the frame period.

The first set of SSs and the other sets of SSs may be configured for a frame period configuration (referred to as a first frame period configuration). Different frame periods may have different frame period configurations. The plurality of consecutive frame periods may have the same frame period configuration. If the first frame period configuration is changed to a different second frame period configuration, detection in the first set of SSs may be stopped and detection of the first signal may be performed in one or more sets of SSs associated with the second frame period configuration. In another example, multiple sets of SSs associated with different frame period configurations are monitored in parallel.

The set of SSs used for detection of the first signal may be associated with different services. For example, a first set of SSs may be associated with one service, such as an eMBB service. One or more additional sets of SSs may also be configured for detection of the first signal. Accordingly, the first device 310 may perform detection of the first signal in one or more additional sets of SSs within the frame period while performing detection in the first set of SSs. The additional set of SSs may be associated with one or more different additional services, such as URLLC services and other services. Different sets of SSs associated with different services may have different granularity of monitoring opportunities. For example, a service with higher latency requirements may be associated with a set of SSs with smaller granularity to guarantee higher latency requirements.

At block 410, the first device 310 determines whether a first signal is detected in at least a first set of SSs within a frame period. At block 415, if it is determined that the first signal is detected in at least the first set of SSs, the first device 310 detects additional signals (referred to as second signals) from the second device 320 in at least a set of SSs (referred to as a second set of SSs) associated with the first set of SSs within the frame period. There may be multiple sets of SSs associated with the first set of SSs (including the second set of SSs). In this case, the first device 310 performs detection of the second signal in a plurality of SS sets within the frame period.

The second signal may comprise any suitable signal associated with the first signal. In example embodiments where the first signal indicates the start of a COT acquired by the second device 320, the second signal may include DCI. In this case, after the first device 310 detects the start of the COT acquired by the second device 320, the first device 310 may monitor the DCI centrally in the second SS until the end of the COT within the frame period for unicast or broadcast DCI delivery. In other words, the detection of the second signal may correspond to the monitoring of the DCI.

In addition to the first set of SSs, the second set of SSs may be associated with one or more additional sets of SSs for detection of the first signal within the frame period. For example, if multiple sets of SSs are configured for detection of a first signal within a frame period, a second set of SSs may be associated with all or at least a subset of the first multiple sets of SSs.

Fig. 5 illustrates an example SS set configuration 500 within a frame period 505, according to some example embodiments of the present disclosure.

In this example, the frame period 505 is implemented by the FFP105 as shown in fig. 1 and 2, the FFP105 comprising 8 slots 205, each slot 205 comprising 14 symbols 210. For frame period 505, a first set of SSs 510 is configured to be associated with a second set of SSs 515 and an additional set of SSs 520, labeled SS set #1, SS set #2, and SS set #3, respectively. The first set of SSs 510 is configured to have a half slot cycle in the first two slots 205 from the beginning of the frame period 505. In this example, the first signal is implemented by a signal transmitted on a PDCCH or a GC-PDCCH. Accordingly, in the first set of SSs 510, a GC-PDCCH Radio Network Temporary Identity (RNTI) or cell-RNTI (C-RNTI) may be utilized to detect PDCCH candidates.

As shown in fig. 5, a second set of SSs 515 occupies one symbol 210 with a double slot period over all slots 205, and a further set of SSs 520 occupies two symbols 210 with a single slot period over all slots 205. The second set of SSs 515 is configured with GC-PDCCH RNTI and the further set of SSs 520 is configured with C-RNTI for signal detection.

The locations or monitoring occasions of the first set of SSs and the second set of SSs, as well as other sets of SSs, may be obtained by the first device in any suitable manner. In some example embodiments, the location of the set of SSs may be indicated by parameters such as offset (e.g., starting location in time domain), period (e.g., slot period), and duration (e.g., number of symbols). These parameters may indicate the absolute location of the SS sets in the time domain, e.g., by the number of subframes, the number of slots and symbols, or their modulus.

Alternatively or additionally, these parameters, such as offset, period, and duration, may indicate the relative position of the set of SSs with respect to the frame period. For example, the offset of the set of SSs may be indicated with respect to the beginning of the frame period. Further, the set of SSs may be repeated periodically within a frame period in a given monitoring pattern. Accordingly, the number of repetitions of the set of SSs or/and the monitoring pattern may be indicated with respect to the frame period.

The monitoring locations of the respective sets of SSs may be preconfigured or dynamically configured in the network. For example, the first device 310 may receive an indication of an SS set configuration from the network side via the second device 320. In an example embodiment in which the first device 310 is implemented by a terminal device and the second device 320 is implemented by a network device, for example, the first device 310 may receive an indication from the second device 320 via higher layer signaling, such as Radio Resource Control (RRC) signaling. The second device 320 may also use other signaling to indicate the SS set configuration to the first device 310.

In some example embodiments, similar to the SS set configuration, the association between an independent SS set (such as a first SS set) and a dependent SS set (such as a second SS set) may also be preconfigured or dynamically indicated in the network. Thus, the first device 310 may obtain the association from the network side via the second device 320. For example, the first device 310 may receive an indication of an association between a first set of SSs and a second set of SSs from the second device 320.

The bit information indication may be used to indicate association. For example, if the second set of SSs is associated with all sets of SSs configured for detection of the first signal within the frame period, the association may be indicated by only one bit indicating linkage of the second set of SSs with all sets of SSs for detection of the first signal. Alternatively or additionally, the bitmap may be used to indicate the linking of the second set of SSs with all or only a subset of the first plurality of sets of SSs.

In some example embodiments, where a first signal is monitored in parallel in a first set of SSs and one or more additional sets of SSs associated with different services within a frame period, if it is determined at block 410 that the first signal is detected in the first set of SSs at block 410, the first device 310 may cease detection of the first signal in the additional sets of SSs until a next frame period.

The stop may be implemented by default. Alternatively or additionally, the stop may be triggered based on explicit signaling. For example, if data of only one service is to be transmitted to the first device 310, the first device 310 receives an indication to cease detection of at least the first signal in a set of SSs associated with a different service, and the first device 310 may cease detection of the first signal in a set of other SSs associated with the different service. The indication may indicate to stop detecting other signals or information that may be transmitted in parallel with the first signal. The indication of the cessation may be accomplished through explicit signaling (e.g., DCI) transmitted in a first set of SSs associated with the service and/or a second set of SSs associated with the first set of SSs.

If the first device 310 determines at block 410 that the first signal is not detected in the first set of SSs, the first device 310 will suspend detection or monitoring in any set of SSs configured within the frame period until the next frame period. Thus, complexity and power consumption may be reduced at the first device 310. Furthermore, in example embodiments where SS set configurations are associated with service and frame period configurations, search space dependencies provide flexibility for monitoring using diverse services or FBE configurations. The indication may also be provided implicitly by determining that the first signal is detected from one of the plurality of sets of SSs, while concurrently monitoring the plurality of sets of SSs having different frame period configurations.

Example monitoring behavior at the first device 310 will be discussed with reference to fig. 6, which fig. 6 illustrates an example SS set configuration 600 in accordance with some example embodiments of the present disclosure.

In fig. 6, two

consecutive frame periods

605 and 610 are shown having the same SS set configuration. Similar to the frame period 505, the

frame periods

605 and 610 are implemented by the FFP105 as shown in fig. 1 and 2. The SS set configuration within the two

frame periods

605 and 610 is the same as the SS set configuration 500 shown in fig. 5 and will not be described again.

In the previous frame period 605, the first device 310 monitors a first set of SSs 615 (having a configuration similar to the first set of SSs 510 shown in fig. 5), labeled as set #1, to detect a first signal indicating the start of the COT acquired by the second device 320. In this frame period 605, the first device 310 does not detect the first signal in the first set of SSs 615. Thus, the first device 310 does not monitor the second set of SSs 620 (having a configuration similar to the second set of SSs 515 shown in fig. 5) and the additional set of SSs 625 (having a configuration similar to the additional set of SSs 520 shown in fig. 5), labeled as set #2 and set #3 of SSs.

In a later frame period 610, the first device 310 missed the first signal in the first monitoring opportunity 630, but found the first signal in the second monitoring opportunity 635 in the first set of SSs 615. Thus, the first device 310 determines that the start of the COT is detected, and then the first device 310 starts monitoring the second set of SSs 620 and the additional set of SSs 625 from the

monitoring occasions

640 and 645 until the end of the COT within the later frame period 610. Further, the first device 310 may monitor the DL slot until the end of the COT in the later frame period 610. The DL slot may be indicated by the second device 320, for example, by a Slot Format Indication (SFI) carried in the GC-PDCCH. Further, the first device 310 suspends the detection of the first signal until the next frame period (not shown) to reduce complexity and power consumption.

Fig. 7 is a simplified block diagram of a device 700 suitable for implementing an example embodiment of the present disclosure. The device 700 may be implemented at or as part of the first device 310 shown in fig. 3.

As shown, device 700 includes a processor 710, a memory 720 coupled to processor 710, a communication module 730 coupled to processor 710, and a communication interface (not shown) coupled to communication module 730. The memory 720 stores at least a program 740. The communication module 730 is used for bi-directional communication, e.g., via multiple antennas. The communication interface may represent any interface required for communication.

The programs 740 are assumed to include program instructions that, when executed by the associated processor 710, enable the device 700 to operate in accordance with example embodiments of the present disclosure, as discussed herein with reference to fig. 1-6. The example embodiments herein may be implemented by computer software executable by the processor 710 of the device 700, or by hardware, or by a combination of software and hardware. The processor 710 may be configured to implement various example embodiments of the present disclosure.

The memory 720 may be of any type suitable to the local technology network and may be implemented using any suitable data storage technology, such as non-transitory computer-readable storage media, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. Although only one memory 720 is shown in device 700, there may be several physically distinct memory modules in device 700. The processor 710 may be of any type suitable for a local technology network, and may include, by way of non-limiting example, one or more of the following: general purpose computers, special purpose computers, microprocessors, Digital Signal Processors (DSPs) and processors based on a multi-core processor architecture. Device 700 may have multiple processors, such as an application specific integrated circuit chip that is time dependent from a clock synchronized to the main processor.

When the device 700 is acting as the first device 310 or part of the first device 310, the processor 710 and the communication module 730 may cooperate to implement the method 400 as described above with reference to fig. 1-6. All of the operations and features described above with reference to fig. 1-6 are equally applicable to the device 700 and have similar effects. Details will be omitted for simplicity.

In general, the various example embodiments of this disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the example embodiments of this disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product comprises computer executable instructions, such as instructions included in program modules, that are executed in a device on a target real or virtual processor to perform the method 400 as described above with reference to fig. 1-6. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various example embodiments, the functionality of the program modules may be combined or split between program modules as desired. Machine-executable instructions of program modules may be executed within local or distributed devices. In a distributed facility, program modules may be located in both local and remote memory storage media.

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

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

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

Further, while operations are described in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking and parallel processing may be advantageous. Also, while several specific implementation details are included in the above discussion, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular example embodiments. Certain features that are described in the context of separate example embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple example embodiments separately or in any suitable subcombination.

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

Various example embodiments of these techniques have been described. In addition to or instead of the above, the following embodiments are described. Features described in any of the examples below may be used with any of the other examples described herein.

In some aspects, a first device comprises: at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the first apparatus to: performing detection of a first signal from a second device in at least a first set of search spaces within a frame period; determining whether the first signal is detected in the at least first set of search spaces within the frame period; and in response to determining that the first signal is detected in the at least first set of search spaces, performing detection of a second signal from the second device in at least a second set of search spaces associated with the first set of search spaces within the frame period.

In some example embodiments, the at least first set of search spaces is configured for a first frame period configuration.

In some example embodiments, the first device is further caused to: in response to receiving an indication to change from the first frame period configuration to a different second frame period configuration, ceasing the detecting of the first signal in the at least first set of search spaces configured for the first frame period configuration and performing the detecting of the first signal in one or more sets of search spaces configured for the second frame period configuration.

In some example embodiments, the first set of search spaces is associated with a service.

In some example embodiments, the first device is caused to perform the detecting of the first signal by: performing the detection of the first signal from the second device in the first search space set associated with the service and one or more further search space sets associated with one or more different further services within the frame period.

In some example embodiments, the first device is further caused to: ceasing the detection of the first signal in the one or more further sets of search spaces associated with the one or more different further services in response to at least one of: determining that the first signal is detected in at least the first set of search spaces associated with the service, and receiving an indication to cease the detection of at least the first signal in sets of search spaces associated with different services over the frame period.

In some example embodiments, the at least second set of search spaces is further associated with one or more additional sets of search spaces for the detection of the first signal within the frame period.

In some example embodiments, the first device is further caused to: in response to determining that the first signal is detected in the at least first search space set, ceasing the detection of the first signal in the at least first search space set for the frame period.

In some example embodiments, the first signal indicates at least that a channel is occupied by the second device within the frame period.

In some example embodiments, the first device is caused to perform the detecting of the second signal by: performing the detection of the second signal from the second device in the second search space until an end of a channel occupancy time within the frame period.

In some example embodiments, the first device is further caused to: receiving, from the second device, an indication of an association between one or more sets of search spaces configured for detection of the first signal and one or more sets of search spaces configured for the detection of the second signal.

In some example embodiments, the first device is further caused to: receiving, from the second device, an indication of at least one of: an offset of at least one of the first search space set and the second search space set relative to a start of the frame period, a period of at least one of the first search space set and the second search space set within the frame period, and a duration of at least one of the first search space set and the second search space set.

In some example embodiments, the frame period comprises a fixed frame period.

In some example embodiments, the first device comprises a terminal device and the second device comprises a network device.

In some aspects, a method implemented at a first device, comprising: performing detection of a first signal from a second device in at least a first set of search spaces within a frame period; determining whether the first signal is detected in the at least first set of search spaces within the frame period; and in response to determining that the first signal is detected in the at least first set of search spaces, performing detection of a second signal from the second device in at least a second set of search spaces associated with the first set of search spaces within the frame period.

In some example embodiments, the method further comprises: in response to receiving an indication to change from the first frame period configuration to a different second frame period configuration, ceasing the detecting of the first signal in the at least first set of search spaces configured for the first frame period configuration and performing the detecting of the first signal in one or more sets of search spaces configured for the second frame period configuration.

In some example embodiments, the method further comprises: performing the detection of the first signal from the second device in the first search space set associated with the service and one or more further search space sets associated with one or more different further services within the frame period.

In some example embodiments, the method further comprises: ceasing the detection of the first signal in the one or more further sets of search spaces associated with the one or more different further services in response to at least one of: determining that the first signal is detected in the first set of search spaces associated with the service, and receiving an indication to cease the detection of at least the first signal in sets of search spaces associated with different services over the frame period.

In some example embodiments, the method further comprises: in response to determining that the first signal is detected in the at least first search space set, ceasing the detection of the first signal in the at least first search space set for the frame period.

In some example embodiments, performing the detection of the second signal comprises: performing the detection of the second signal from the second device in the second search space until an end of a channel occupancy time within the frame period.

In some example embodiments, the method further comprises: receiving, from the second device, an indication of an association between one or more sets of search spaces configured for detection of the first signal and one or more sets of search spaces configured for the detection of the second signal.

In some example embodiments, the method further comprises: receiving, from the second device, an indication of at least one of: an offset of at least one of the first search space set and the second search space set relative to a start of the frame period, a period of at least one of the first search space set and the second search space set within the frame period, and a duration of at least one of the first search space set and the second search space set.

In some example embodiments, the frame period comprises a fixed frame period.

In some aspects, an apparatus comprises: means for performing detection of a first signal from a second device in at least a first set of search spaces within a frame period; means for determining whether the first signal is detected in the at least first set of search spaces within the frame period; and means for performing detection of a second signal from the second device in at least a second set of search spaces associated with the first set of search spaces within the frame period in response to determining that the first signal is detected in the at least first set of search spaces.

In some example embodiments, the apparatus further comprises: means for stopping the detection of the first signal in the at least a first set of search spaces configured for the first frame period configuration and performing detection of the first signal in one or more sets of search spaces configured for the second frame period configuration in response to receiving an indication to change from the first frame period configuration to a different second frame period configuration.

In some example embodiments, the apparatus further comprises means for performing the detection of the first signal from the second device in the first set of search spaces associated with the service and one or more additional sets of search spaces associated with one or more different additional services within the frame period.

In some example embodiments, the apparatus further comprises: means for ceasing the detection of the first signal in the one or more further sets of search spaces associated with the one or more different further services in response to at least one of: determining that the first signal is detected in the first set of search spaces associated with the service, and receiving an indication to cease the detection of at least the first signal in sets of search spaces associated with different services over the frame period.

In some example embodiments, the apparatus further comprises: means for ceasing the detection of the first signal in the at least first search space set within the frame period in response to determining that the first signal is detected in the at least first search space set.

In some example embodiments, the means for performing the detection of the second signal comprises: means for performing the detection of the second signal from the second device in the second search space until an end of a channel occupancy time within the frame period.

In some example embodiments, the apparatus further comprises: means for receiving, from the second device, an indication of an association between one or more sets of search spaces configured for detection of the first signal and one or more sets of search spaces configured for the detection of the second signal.

In some example embodiments, the apparatus further comprises: means for receiving, from the second device, an indication of at least one of: an offset of at least one of the first search space set and the second search space set relative to a start of the frame period, a period of at least one of the first search space set and the second search space set within the frame period, and a duration of at least one of the first search space set and the second search space set.

In some example embodiments, the frame period comprises a fixed frame period.

In some aspects, a computer-readable storage medium includes program instructions stored thereon that, when executed by a processor of a device, cause the device to perform a method according to some example embodiments of the present disclosure.

Claims

1. A first device, comprising:

at least one processor; and

at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the first apparatus to:

performing detection of a first signal from a second device in at least a first set of search spaces within a frame period;

determining whether the first signal is detected in the at least first set of search spaces within the frame period; and

in response to determining that the first signal is detected in the at least first set of search spaces, performing detection of a second signal from the second device in at least a second set of search spaces associated with the first set of search spaces within the frame period.

2. The first device of claim 1, wherein the at least first set of search spaces is configured for a first frame period configuration.

3. The first device of claim 2, wherein the first device is further caused to:

in response to receiving an indication to change from the first frame period configuration to a different second frame period configuration, ceasing the detecting of the first signal in the at least first set of search spaces configured for the first frame period configuration and performing the detecting of the first signal in one or more sets of search spaces configured for the second frame period configuration.

4. The first device of claim 1, wherein the first set of search spaces is associated with a service.

5. The first device of claim 4, wherein performing the detection of the first signal comprises:

performing the detection of the first signal from the second device in the first search space set associated with the service and one or more further search space sets associated with one or more different further services within the frame period.

6. The first device of claim 5, wherein the first device is further caused to:

ceasing the detection of the first signal in the one or more further sets of search spaces associated with the one or more different further services in response to at least one of:

determining that the first signal is detected in the first set of search spaces associated with the first service, an

Receiving an indication to cease the detection of at least the first signal in a set of search spaces associated with different services within the frame period.

7. The first device of claim 1, wherein the at least second set of search spaces is further associated with one or more additional sets of search spaces for the detection of the first signal within the frame period.

8. The first device of claim 1, wherein the first device is further caused to:

in response to determining that the first signal is detected in the at least first search space set, ceasing the detection of the first signal in the at least first search space set for the frame period.

9. The first device of claim 1, wherein the first signal indicates at least that a channel is occupied by the second device within the frame period.

10. The first device of claim 9, wherein the first device is caused to perform the detection of the second signal by:

performing the detection of the second signal from the second device in the second search space until an end of a channel occupancy time within the frame period.

11. The first device of claim 1, wherein the first device is further caused to:

receiving, from the second device, an indication of an association between one or more sets of search spaces configured for detection of the first signal and one or more sets of search spaces configured for the detection of the second signal.

12. The first device of claim 1, wherein the first device is further caused to:

receiving, from the second device, an indication of at least one of:

an offset of at least one of the first search space set and the second search space set relative to a start of the frame period,

a period of at least one of the first search space set and the second search space set within the frame period, an

A duration of at least one of the first set of search spaces and the second set of search spaces.

13. The first device of claim 1, wherein the frame period comprises a fixed frame period.

14. The first device of claim 1, wherein the first device comprises a terminal device and the second device comprises a network device.

15. A method implemented at a first device, comprising:

16. The method of claim 15, wherein the at least first set of search spaces is configured for a first frame period configuration.

17. The method of claim 16, further comprising:

18. The method of claim 15, wherein the first set of search spaces is associated with a service.

19. The method of claim 18, further comprising:

20. The method of claim 19, further comprising:

determining that the first signal is detected in the first set of search spaces associated with the service, an

21. The method of claim 15, wherein the at least second set of search spaces is further associated with one or more additional sets of search spaces used for the detection of the first signal within the frame period.

22. The method of claim 15, further comprising:

23. The method of claim 15, wherein the first signal indicates at least that a channel is occupied by the second device within the frame period.

24. The method of claim 23, wherein performing the detection of the second signal comprises:

25. The method of claim 15, further comprising:

26. The method of claim 15, further comprising:

receiving, from the second device, an indication of at least one of:

27. The method of claim 15, wherein the frame period comprises a fixed frame period.

28. The method of claim 15, wherein the first device comprises a terminal device and the second device comprises a network device.

29. An apparatus, comprising:

means for performing detection of a first signal from a second device in at least a first set of search spaces within a frame period;

means for determining whether the first signal is detected in the at least first set of search spaces within the frame period; and

means for performing detection of a second signal from the second device in at least a second set of search spaces associated with the first set of search spaces within the frame period in response to determining that the first signal is detected in the at least first set of search spaces.

30. A computer readable storage medium comprising program instructions stored thereon which, when executed by a processor of an apparatus, cause the apparatus to perform the method of any of claims 15 to 28.