OPTIONALLY PERFORMING A LISTEN-BEFORE-TALK OPERATION

Apparatuses, methods, and systems are disclosed for optionally performing a listen-before-talk operation. One method includes configuring communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the method includes receiving information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

FIELD

The subject matter disclosed herein relates generally to wireless communications and more particularly relates to optionally performing a listen-before-talk operation.

BACKGROUND

In certain wireless communications networks, listen-before-talk operations may be performed. In such networks, listen-before-operations may overload resources.

BRIEF SUMMARY

Methods for optionally performing a listen-before-talk operation are disclosed. Apparatuses and systems also perform the functions of the methods. One embodiment of a method includes configuring, at a user equipment, communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the method includes receiving information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

One apparatus for optionally performing a listen-before-talk operation includes a user equipment. In some embodiments, the apparatus includes a processor that configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In various embodiments, the apparatus includes a receiver that receives information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

Another embodiment of a method for optionally performing a listen-before-talk operation includes configuring, at a network unit, communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the method includes transmitting information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

Another apparatus for optionally performing a listen-before-talk operation includes a network unit. In some embodiments, the apparatus includes a processor that configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In various embodiments, the apparatus includes a transmitter that transmits information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

DETAILED DESCRIPTION

FIG.1depicts an embodiment of a wireless communication system100for optionally performing a listen-before-talk operation. In one embodiment, the wireless communication system100includes remote units102and network units104. Even though a specific number of remote units102and network units104are depicted inFIG.1, one of skill in the art will recognize that any number of remote units102and network units104may be included in the wireless communication system100.

The network units104may be distributed over a geographic region. In certain embodiments, a network unit104may also be referred to and/or may include one or more of an access point, an access terminal, a base, a base station, a location server, a core network (“CN”), a radio network entity, a Node-B, an evolved node-B (“eNB”), a 5G node-B (“gNB”), a Home Node-B, a relay node, a device, a core network, an aerial server, a radio access node, an access point (“AP”), new radio (“NR”), a network entity, an access and mobility management function (“AMF”), a unified data management (“UDM”), a unified data repository (“UDR”), a UDM/UDR, a policy control function (“PCF”), a radio access network (“RAN”), a network slice selection function (“NSSF”), an operations, administration, and management (“OAM”), a session management function (“SMF”), a user plane function (“UPF”), an application function, an authentication server function (“AUSF”), security anchor functionality (“SEAF”), trusted non-3GPP gateway function (“TNGF”), or by any other terminology used in the art. The network units104are generally part of a radio access network that includes one or more controllers communicably coupled to one or more corresponding network units104. The radio access network is generally communicably coupled to one or more core networks, which may be coupled to other networks, like the Internet and public switched telephone networks, among other networks. These and other elements of radio access and core networks are not illustrated but are well known generally by those having ordinary skill in the art.

In one implementation, the wireless communication system100is compliant with NR protocols standardized in third generation partnership project (“3GPP”), wherein the network unit104transmits using an OFDM modulation scheme on the downlink (“DL”) and the remote units102transmit on the uplink (“UL”) using a single-carrier frequency division multiple access (“SC-FDMA”) scheme or an orthogonal frequency division multiplexing (“OFDM”) scheme. More generally, however, the wireless communication system100may implement some other open or proprietary communication protocol, for example, WiMAX, institute of electrical and electronics engineers (“IEEE”) 802.11 variants, global system for mobile communications (“GSM”), general packet radio service (“GPRS”), universal mobile telecommunications system (“UMTS”), long term evolution (“LTE”) variants, code division multiple access 2000 (“CDMA2000”), Bluetooth®, ZigBee, Sigfoxx, among other protocols. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

In various embodiments, a remote unit102may configure communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the remote unit102may receive information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling. Accordingly, the remote unit102may be used for optionally performing a listen-before-talk operation.

In certain embodiments, a network unit104may configure communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the network unit104may transmit information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling. Accordingly, the network unit104may be used for optionally performing a listen-before-talk operation.

In certain embodiments, the processor202configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In various embodiments, the receiver212receives information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

Although only one transmitter210and one receiver212are illustrated, the remote unit102may have any suitable number of transmitters210and receivers212. The transmitter210and the receiver212may be any suitable type of transmitters and receivers. In one embodiment, the transmitter210and the receiver212may be part of a transceiver.

In certain embodiments, the processor302configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In various embodiments, the transmitter310transmits information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In certain networks, listen-before talk (“LBT”) may not be used. In such networks, no-LBT type transmissions may be made; however, to maintain coexistence with Wi-Fi and other operators, usage of LBT may be preferred. In some embodiments, there may be operation of a no-lo LBT mode if there is low interference and there may be a fallback mode of switching from no-LBT to LBT.

In various embodiments, there may be a procedure and signaling for dynamic LBT (e.g., switching from LBT to no-LBT and vice versa) which may consider channel occupancy, beams, and so forth.

In certain embodiments there may be: 1) different configuration and signaling options for the transmission of a switching indication per beam for switching between LBT to no-LBT and vice versa; 2) a user equipment (“UE”) initiated switching per beam between LBT to no-LBT and vice versa; 3) different UE procedures for describing switching between LBT and no-LBT mode and vice versa for a beam; and/or 4) different UE procedures describing LBT and no-LBT mode considering different beams.

In a first embodiment, there may be a configuration of LBT and no-LBT mode per beam basis. According to the first embodiment, in a cell containing users with both LBT and no-LBT modes, then the LBT and no-LBT mode configuration may be defined per beam and/or per a spatial filter.

For transition from LBT to No-LBT, long term interference statistics such as layer 3 (“L3”) reference signal received power (“RSRP”) (“L3-RSRP”) and/or reference signal received quality (“RSRQ”) measured in a configured window duration defined in terms of slots, msec per beam, spatial filter, and/or quasi-co-located (“QCLed”) assumptions are compared against a configured interference threshold and, if the measured interference is below the configured threshold for a beam and/or spatial filter then the transmitter (e.g., such as a gNB or a UE), may switch the beam and/or the spatial filter from LBT to no-LBT mode. In some embodiments, hybrid automatic repeat request (“HARQ”) acknowledgement (“ACK”) (“HARQ-ACK”) reported in a configured window duration that is defined in terms of slots, msec per beam, and/or spatial filter may be used as a metric to detect interference by measuring a percentage or ratio of ACKs against non-acknowledgements (“NACKs”) in a configured window and, if that percentage or ratio is above certain configured threshold, then the gNB may switch the beam and/or spatial filter from an LBT mode to a no-LBT mode. In various embodiments, a percentage or ratio is reported by a receiver to a transmitter. In certain embodiments, a consecutive number of ACKs exceeding a threshold may be used as a metric for switching from LBT to no-LBT. In some embodiments, a consecutive number or whether the consecutive number exceeds a threshold is reported by a receiver to a transmitter. In various embodiments, a threshold is determined or configured by a network or communication system.

For no-LBT to LBT: 1) a counter may be defined, and the counter value is incremented each time if the consecutive NACKs or discontinuous transmission (“DTX”) is above a certain configured threshold value and, if the counter value is above the certain configured threshold, then the transmitter may decide to switch from an no-LBT to an LBT mode; 2) measured long term interference statistics such as L3-RSRP and/or RSRQ above a certain configured threshold may be used as a criterion for the transmitter to switch to the LBT mode; 3) by measuring a percentage or ratio of NACKs and/or DTX against ACKs in a configured window above the certain configured threshold may be used; and/or 4) consecutive NACKs or DTX may be a metric for switching to the LBT mode.

In certain embodiments, a gNB may transmit a switching indicator that may be a one-bit indication for an LBT mode or a no-LBT mode. As an example, the switching indicator having a value of “0” may indicate a no-LBT mode and the value of “1” may indicate an LBT mode.

In some embodiments, a separate group common downlink configuration indicator (“DCI”) may be used and a radio network temporary identifier (“RNTI”) may be used for monitoring the separate group common DCI. The RNTI may be different from another RNTI used for a group common DCI so that the receiver may distinguish group common DCIs by the RNTI. In various embodiments, group common DCI format 2-0 may be extended with a field (e.g., using reserved bits) to indicate a switching indicator. In certain embodiments, DCI providing a UL grant may be extended with a field to indicate a switching indicator.

In some embodiments, semi-static signaling, such as RRC signaling, may be used to signal a switching indicator. In various embodiments, a new medium access control (“MAC”) control element (“CE”) may be defined, or an existing MAC CE may be extended to provide a switching indicator. In certain embodiments, radio resource control (“RRC”) common signaling may indicate LBT or no-LBT for a beam, quasi-co-location (“QCL”), or set of beams.

In some embodiments, signaling of LBT and no-LBT and vice versa switching may be transmitted only in relevant beams where the switching is to be performed.

In various embodiments, whether a UE needs to perform a cat 4 type LBT or a cat 2 type LBT for switching from no-LBT to LBT may be specified. In certain embodiments, a configurable sensing duration of a cat 2 type LBT and/or applicability of a random back off and/or fixed or variable contention window size may be specified.

In certain embodiments, signaling may contain at least one additional parameter.

In some embodiments, the at least one additional parameter may include a duration of LBT or no-LBT mode of operation per beam or set of beams. In such embodiments, the UE is informed, within a switching signaling method, of a duration in terms of slots or msec for the LBT mode or no-LBT mode to be active. In one implementation of such embodiments, duration may be signaled as a maximum channel occupancy time (“MCOT”) duration for LBT mode or no-LBT mode signaled using DCI or using RRC and/or MAC CE and the duration is measured from the starting symbol of a first slot (e.g., after the switching) to the last symbol of a slot. In another implementation of such embodiments, an index of a table containing a value of a duration is signaled to the UE.

In various embodiments, the at least one additional parameter may include to indicate an LBT or no-LBT mode to be used after a specified duration. The UE is informed, within a switching method, with information that specifies UE behavior after finishing the specified duration. In one implementation of such embodiments, if the UE is asked to switch from a first mode (e.g., LBT) to a second mode (e.g., no-LBT) for a certain duration, then after finishing the duration, an explicit indication (e.g., one bit) may inform the UE about whether to continue using the second mode or fallback to the first mode.

In certain embodiments, the at least one additional parameter may include an explicit indication that may be transmitted using DCI, RRC signaling, or MAC CE. Absence of any explicit indication from a gNB may make a UE return to a configured (or preconfigured) fallback mode (e.g., an LBT mode).

In some embodiments, the at least one additional parameter may start an LBT or no-LBT mode of operation per beam or set of beams. The UE is informed, within a switching method, about when to switch (e.g., relative time offset in terms of symbols, slots, and/or msec may be specified). Offset may be calculated from a last symbol of a slot where it received the signaling. DCI, RRC signaling, or MAC CE may carry this offset.

In various embodiments, the at least one additional parameter may include beam specific details like QCL assumptions in which an LBT and/or no-LBT is applicable. RRC common signaling may indicate LBT or no-LBT for a beam, QCL, or set of beams. In such embodiments, DCI signaling may indicate a TCI state for which the LBT and/or no-LBT is applicable.

In certain embodiments, the at least one additional parameter may include a flag to indicate a new radio unlicensed (“NR-U”) mechanism for a no-LBT mode. In such embodiments, the UE is signaled separately about handling of a NR-U mechanism for the no-LBT mode like autonomous selection of a HARQ process identifier (“ID”), a configured grant (“CG”) retransmission timer, and/or search space switching to indicate whether the no-LBT mode is allowed or not allowed.

In certain embodiments, there may be a configured set (or preconfigured set) of CG resource for LBT and no-LBT modes that are signaled to the UE and the UE may activate and/or deactivate resources from those configured CG resource based on a switching indication. In one implementation, a switching indicator itself activates and/or deactivates corresponding CG resource from the configured set. In another implementation, a separate signaling for activation and/or deactivation may be RRC or DCI signaling.

In some embodiments, there may be UE requested switching from an LBT to a no-LBT mode such as: 1) UE initiated switching from LBT to no-LBT mode may be performed by transmitting a request for switching using a specific scheduling resource (“SR”) configuration or specific random access channel (“RACH”) preamble—the RACH preamble may be beneficially an indicated or configured preamble so that the corresponding RACH procedure is contention-free; 2) the UE may transmit a SR and/or RACH preamble if a measured interference level is below a certain configured threshold—in one implementation, a UE, after encountering configurable LBT failures and/or based on a priority (e.g., reliability and/or latency) of the data transmission, may be allowed to switch to the No-LBT mode by embodiments described herein; and/or 3) a gNB may decide to accept or deny a request for switching from UE based on aggregated measurements from UEs served by that beam and/or set off beams. In response to a request from the UE, the gNB may transmit the switching indicator as described using embodiments described herein.

In various embodiments, there may be autonomous switching from an LBT to a no-LBT mode such as: 1) interference level measurement may be associated with the autonomous switching and, as an example, with an interference level lower than a threshold, switching from LBT to no-LBT is enabled and while at an interference level higher than a threshold, short LBT of cat 2 is performed; 2) configurable sensing duration for cat 2 may be defined such that longer sensing duration may be configured for a high reliability traffic type; and/or 3) separation of cat 2, cat 4, and no-LBT mode of access may configured per logical channel (“LCH”), or otherwise classified based on channel access priority class (“CAPC”) values.

In certain embodiments, there may be autonomous switching from a no-LBT to an LBT mode such as: 1) a gNB or a UE may autonomously switch from no-LBT to LBT mode based on a configurable percentage or ratio of received NACKs to ACKs, or based on a number of consecutive NACKs—for example, a high ratio of NACKs to ACKs or a large number of consecutive NACKS for transmissions may be a sign that the transmissions faced adverse effects caused by collisions on the channel—in such a case, going to LBT mode to avoid collisions may improve the data transmission of the UE, as well as of other transmitters in the system; 2) an interference level measurement may be a metric for autonomous switching from no-LBT to LBT—as an example, for an interference level higher than a threshold, the gNB or UE may autonomously switch from no-LBT to LBT—the detailed LBT category, such as Cat 2 or Cat 4, may be defined (e.g., per traffic type and/or beam); and/or 3) for unlicensed access in regions where both LBT and no-LBT based channel access mechanism can be employed, the LBT type to be used may be associated with the traffic and/or UE priority type. In one implementation, an ultra-reliable low-latency communication (“URLLC”) device is associated with no-LBT based channel access mechanism and enhanced mobile broadband (“eMBB”) device is associated with only LBT-based channel access mechanism. In some embodiments, a same device with two different priority traffic such as eMBB traffic and URLLC traffic may be configured to use both LBT and no-LBT type for intra-UE multiplexing of eMBB and URLLC. In various embodiments, eMBB traffic and/or the UE may be associated with both LBT and no-LBT based channel access mechanisms, where the UE is required first to perform LBT based channel access at least for N number of times (e.g., configured and/or indicated by a network) and upon failure for all N instances, the UE is allowed to perform a no-LBT based channel access mechanism. In certain embodiments, URLLC traffic and/or a UE may be associated with both LBT and no-LBT based channel access mechanisms, where the UE is required first to perform LBT based channel access at least for M number of times (e.g., configured and/or indicated by a network and M is less than or equal to N, N being the counter for eMBB UE and/or traffic) and upon failure for all M instances, the UE is allowed to perform a no-LBT based channel access mechanism.

In a second embodiment, there may be a UE procedure for switching between LBT and no-LBT modes. According to the second embodiment, there may be at least a first case, a second case, and a third case for switching from the LBT mode to the no-LBT mode and vice versa.

In the first case, there may be switching from the LBT mode to the no-LBT mode. If a UE receives an LBT to no-LBT switching indication for a beam, a configurable gap (or no gap) may be applied before starting no-LBT. One or more of the following may be applied during switching: 1) the UE waits until any on-going transmission within a current remaining channel occupancy time (“COT”) initiated based on LBT is finished before switching to the no-LBT mode, where the no-LBT mode is initiated using a new COT (e.g., if MCOT is configured to be used in the no-LBT mode); 2) the UE switches to the No-LBT mode immediately in the current remaining COT—after the COT ends, the UE uses the no-LBT mode using a new COT (e.g., if MCOT is configured to be used in a no-LBT mode); 3) the UE ends the current COT initiated based on LBT immediately and switches to no-LBT mode using a new COT (e.g., if MCOT is configured for the no-LBT mode); 4) a separate MCOT may be defined for the LBT mode and the no-LBT mode; and/or 5) the gNB may semi-statically or dynamically indicate one of these options to be used along with the switching indicator.

In the second case, there may be switching from the no-LBT mode to the LBT mode. If a UE receives a no-LBT to LBT switching indication for a beam, a configurable gap may be applied before starting the LBT mode of operation. One of the following may be applied during switching: 1) the UE waits until any on-going transmission within the current remaining COT initiated based on no-LBT (e.g., if MCOT is configured to be used in the no-LBT mode) is finished before switching to the LBT mode, where the LBT mode is initiated using a new COT; 2) the UE switches to the LBT mode immediately in the ongoing COT with a configurable gap (or zero gap) applied before starting the LBT mode of operation—an LBT of cat 2 is performed when switching from no-LBT to LBT in the ongoing COT; 3) the UE ends the current COT immediately and switches to the LBT mode using a new COT—the new COT is initiated based on cat 4 or cat 2; and/or 4) the gNB may semi-statically or dynamically indicate one of these options to be used along with the switching indicator.

In the third case, there may be LBT and/or no-LBT modes of operation in different beams (e.g., multiple beams). The UE may perform the LBT mode and the no-LBT mode parallelly in different beams using different MCOT durations. In other words, the UE may initiate the LBT mode or the no-LBT mode in different beams independently using a new COT. If a COT is associated with more than one beam and, if a switching indication from LBT to no-LBT is received, the UE switches to no-LBT only after the completion of the ongoing COT.

FIG.4is a schematic block diagram illustrating one embodiment of a system400for optionally performing a listen-before-talk operation. The system400includes a UE402and a network unit404. In some embodiments, the UE402may configure406communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In various embodiments, the network unit404may configure408communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In certain embodiments, the network unit404may transmit410information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling

FIG.5is a flow chart diagram illustrating one embodiment of a method500for optionally performing a listen-before-talk operation. In some embodiments, the method500is performed by an apparatus, such as the remote unit102. In certain embodiments, the method500may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

In various embodiments, the method500includes configuring502communications is in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the method500includes receiving504information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling. In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof. In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the method500further comprises receiving a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation. In various embodiments, the method500further comprises transmitting a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.

In one embodiment, the method500further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed after completion of the current carrier occupancy time. In some embodiments, the method500further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately from a next slot.

In certain embodiments, the method500further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately by terminating the current carrier occupancy time and imitating a new carrier occupancy time. In various embodiments, the method500further comprises initiating the listen-before-talk mode of operation or the non-listen-before-talk mode of operation using an independent maximum carrier occupancy time.

FIG.6is a flow chart diagram illustrating another embodiment of a method600for optionally performing a listen-before-talk operation. In some embodiments, the method600is performed by an apparatus, such as the network unit104. In certain embodiments, the method600may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

In various embodiments, the method600includes configuring602communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof. In some embodiments, the method600includes transmitting604information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling. In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof. In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the method600further comprises transmitting a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation. In various embodiments, the method600further comprises receiving a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.

In one embodiment, a method of a user equipment comprises: configuring communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof; and receiving information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling.

In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling.

In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof.

In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the method further comprises receiving a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation.

In various embodiments, the method further comprises transmitting a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.

In one embodiment, the method further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed after completion of the current carrier occupancy time.

In some embodiments, the method further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately from a next slot.

In certain embodiments, the method further comprises determining a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately by terminating the current carrier occupancy time and imitating a new carrier occupancy time.

In various embodiments, the method further comprises initiating the listen-before-talk mode of operation or the non-listen-before-talk mode of operation using an independent maximum carrier occupancy time.

In one embodiment, an apparatus comprises a user equipment. The apparatus further comprises: a processor that configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof; and a receiver that receives information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is received using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling.

In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling.

In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof.

In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the receiver receives a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation.

In various embodiments, the apparatus further comprises a transmitter that transmits a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.

In one embodiment, the processor determines a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, and the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed after completion of the current carrier occupancy time.

In some embodiments, the processor determines a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately from a next slot.

In certain embodiments, the processor determines a time for switching after reception of a switching indication in a current ongoing carrier occupancy time, wherein the time for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is performed immediately by terminating the current carrier occupancy time and imitating a new carrier occupancy time.

In various embodiments, the processor initiates the listen-before-talk mode of operation or the non-listen-before-talk mode of operation using an independent maximum carrier occupancy time.

In one embodiment, a method of a network unit comprises: configuring communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof; and transmitting information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling.

In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling.

In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof.

In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the method further comprises transmitting a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation.

In various embodiments, the method further comprises receiving a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.

In one embodiment, an apparatus comprises a network unit. The apparatus further comprises: a processor that configures communications in an unlicensed spectrum to use a listen-before-talk mode of operation, a non-listen-before-talk mode of operation, or a combination thereof; and a transmitter that transmits information indicating whether to perform a specific data communication using the listen-before-talk mode of operation or the non-listen-before-talk mode of operation. The information indicating whether to perform the specific data communication is transmitted using semi-static cell specific information, semi-static user equipment specific information, dynamic user equipment specific signaling, or dynamic group common signaling.

In some embodiments, the semi-static cell specific information is implemented using radio resource control common signaling.

In certain embodiments, the semi-static user equipment specific signaling is implemented using radio resource control dedicated signaling.

In various embodiments, the dynamic user equipment specific signaling is implemented using dedicated downlink control information or using group common downlink control information that indicates dynamic switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation to fulfil at least one condition.

In one embodiment, switching criteria is determined based on measurement of reference signal received power, reported reference signal received quality, a percentage of hybrid automatic repeat request reports received, a ratio corresponding to a number of hybrid automatic repeat request reports received, a number of consecutive hybrid automatic repeat request reports received, or some combination thereof.

In some embodiments, switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation is cell specific, user equipment specific, user equipment beam specific, or for a set of beams.

In certain embodiments, the transmitter transmits a radio network temporary identifier for reception of group common downlink control information indicating switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation.

In various embodiments, the apparatus further comprises a receiver that receives a request for switching between the listen-before-talk mode of operation and the non-listen-before-talk mode of operation via a scheduling resource or a random access channel transmission.