CN108633097B

CN108633097B - Wireless communication method and user equipment

Info

Publication number: CN108633097B
Application number: CN201710683187.3A
Authority: CN
Inventors: 王轶; 李迎阳; 张世昌
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2017-03-24
Filing date: 2017-08-10
Publication date: 2023-05-09
Anticipated expiration: 2037-08-10
Also published as: CN108633097A

Abstract

The present disclosure provides a method of carrier monitoring and signaling over unlicensed bands. The method comprises the following steps: when the UE operating on the unlicensed frequency band carrier transmits signals based on an automatic uplink transmission mode and adopts the first type of LBT, information related to the LBT priority is required to be determined according to the signaling indication, so that transmission parameters related to the LBT priority are determined. The present disclosure also includes: when selecting the transmission resource, determining the resource according to the LBT information, and determining the CWS adjusting method of the LBT according to the scheduling mode. By the method and the device, the LAA UE and other UEs can coexist in a friendly way, and friendly coexistence among the LAA UEs is ensured.

Description

Wireless communication method and user equipment

Technical Field

The present disclosure relates to the field of mobile communications technology. In particular, the present disclosure relates to a method for carrier monitoring and signaling over unlicensed frequency bands and corresponding devices.

Background

With the increasing explosion of user demand for high-bandwidth wireless services and the increasing contradiction between scarce spectrum resources, mobile operators are beginning to consider unlicensed bands (also known as unlicensed bands) as a complement to licensed bands. The 3GPP has begun to study how to effectively improve the utilization rate of the whole network spectrum on the premise of ensuring that other technologies of the unlicensed band are not affected obviously by effective carrier aggregation of the unlicensed band and the licensed band by deploying LTE on the unlicensed band (the LTE system deployed on the unlicensed band is referred to as a licensed carrier assisted access LAA system). As shown in fig. 1, two transmitting nodes serve the UE at the same time, one providing a larger coverage or a more stable connection through the licensed band carrier and the other providing the hot spot service through the unlicensed band carrier. Both transmitting nodes belong to one base station, and the two transmitting nodes can be co-sited or different stations. In another implementation, the two transmitting nodes may belong to different base stations, i.e. operate by means of a dual connection (DC, dual connectivity). .

Unlicensed bands have generally been allocated for some other use, for example, radar or wireless fidelity of the 802.11 family (WiFi, wireless Fidelity). In the unlicensed band, how to avoid interference between the LAA system and other wireless systems such as radar or WiFi is a key issue. Carrier sensing (CCA) is a collision avoidance mechanism commonly employed on unlicensed bands. A mobile Station (STA) must detect a radio channel before transmitting a signal and can occupy the radio channel only if it is detected to be idle, a listen-before-talk mechanism called LBT (Listen before talk). LAA also needs to follow LBT mechanism for energy detection of the channel.

Before sending a signal, the LAA UE needs to first receive an UL grant sent by the eNB and perform LBT before an uplink subframe indicated by the UL grant. If the eNB sends the UL grant on the carrier in the unlicensed band, downlink LBT needs to be performed first, and the UL grant can be successfully sent. Before uplink subframe transmission of UL grant scheduling, the UE needs to perform uplink LBT, and can successfully transmit PUSCH scheduled by UL grant. Uplink LBT by a UE is classified into two types. One type of LBT, known as Category 4 LBT (TS 36.213.15.2.1.1), determines the size of the Collision Window (CWS), randomly generates a backoff factor X. If all X CCA slots are idle, a signal may be transmitted. The first class of LBTs is divided into four LBT priority classes (LBT priority class), each corresponding to a different QCI (Quality criterion indicator). Different LBT priority class CWS sizes, different back-off time units (different periods), and different maximum channel occupation times MCOT (maximum channel occupancy time) are shown in fig. 2. The type of LBT employed when LAA UE transmission is determined by the base station, and LBT priority class, and the time of the subframe occupied by the base station to ensure that scheduled LAA UE uplink transmission does not exceed the indicated LBT priority class or time required for higher priority (LBT priority class numbered smaller) traffic than indicated LBT priority class. The service type (corresponding to the QCI) actually transmitted by the UE is not limited, and the UE may simply transmit in the allocated time according to the instruction of the eNB.

Another type is called a second type LBT (TS 36.213.15.2.1.2), where the UE only needs to perform a 25us CCA detection before the start of the transmission signal defined by the standard, and if the channel is clear, the signal can be transmitted.

Because uplink transmission based on UL grant scheduling is successful, downlink LBT performed by eNB and uplink LBT performed by UE are required to be successful, the UE can transmit PUSCH, and transmission probability is greatly reduced. Thus, 3GPP starts to consider uplink transmission of automatic uplink transmission (autonomous uplink access) on unlicensed band.

Disclosure of Invention

In uplink transmission based on UL grant scheduling, LBT priority class is indicated in the UL grant, and the scheduling time is guaranteed to meet the requirement by the base station. However, the uplink transmission of the automatic uplink transmission does not have this information and cannot determine the required information, so a new solution is needed.

Furthermore, since the capability of preempting channels is different between automatic uplink transmission and scheduling-based uplink transmission, the LBT parameters should take into account the differentiation of the two.

According to one aspect of the present disclosure, there is provided a method of automatic uplink transmission, including: acquiring listen-before-send (LBT) information; determining LBT parameters according to the LBT information, and determining transmission parameters for automatic uplink transmission; and performing an LBT operation according to the determined LBT parameter, and determining whether a signal can be transmitted on the automatic uplink transmission resource based on the transmission parameter.

In one embodiment, determining the LBT parameter includes: for automatic uplink transmission and uplink transmission based on scheduling, energy detection threshold values are respectively determined.

In one embodiment, determining the LBT parameter includes: the window size CWS is determined independently or partially independently for automatic uplink transmission and scheduling based uplink transmission.

In one embodiment, independently or partially independently determining the window size CWS comprises at least one of:

-maintaining CWS for automatic uplink transmission and scheduling based uplink transmission, respectively, for uplink transmission of the same hybrid automatic repeat request, HARQ, process;

for uplink transmission of the same hybrid automatic repeat request HARQ process, the displayed or implicit ACK/NACK corresponding to the automatic uplink transmission is used for CWS adjustment of the uplink transmission based on the schedule, and the ACK/NACK corresponding to the uplink transmission based on the schedule is not used for CWS adjustment of the uplink transmission of the automatic uplink transmission; and

for uplink transmission of the same hybrid automatic repeat request HARQ process, the displayed or implicit ACK/NACK corresponding to the automatic uplink transmission is not used for CWS adjustment of the scheduling-based uplink transmission, and the ACK/NACK corresponding to the scheduling-based uplink transmission is used for CWS adjustment of the automatic uplink transmission.

In one embodiment, determining the LBT parameter includes: for the purpose ofAutomatic uplink transmission and scheduling-based uplink transmission, respectively determining maximum value CW of continuous use collision window CW _max，p Number K of times (f).

In one embodiment, the transmission parameters include: a time parameter for a resource for automatic uplink transmission, a frequency domain parameter, an indication of whether transmission can be performed or a service type of uplink transmission.

In one embodiment, determining whether signals can be transmitted on the automatic uplink transmission resource comprises: based on the type of LBT, it is determined whether a signal can be transmitted on the selected automatic uplink transmission resource.

In one embodiment, a threshold value Thr1 is configured for the first type of LBT and a threshold value Thr2 is configured for the second type of LBT, thr1 being less than Thr2, such that the probability that the random number generated by the UE is greater than Thr1 is greater than the probability that the random number generated by the UE is greater than Thr 2.

In one embodiment, determining the transmission parameters includes: based on the LBT priority classification, it is determined whether signals can be transmitted on the selected automatic uplink transmission resources.

In one embodiment, threshold values are respectively configured for different LBT priority classes, so that higher LBT priority traffic is sent with a greater probability.

In one embodiment, the LBT indication information is obtained through cell common indication information C-PDCCH and/or higher layer signaling.

In one embodiment, the parameters of the automatic uplink transmission are configured for different LBT priority classifications, and the UE selects the automatic uplink transmission resources according to the LBT priority classifications.

In one embodiment, determining the LBT parameter includes: for uplink transmission of automatic uplink transmission, only the first type of LBT is employed.

In one embodiment, determining the LBT parameter includes: when receiving the maximum channel occupation time MCOT indication information, if the uplink subframe to be automatically transmitted in uplink is located in the uplink subframe set indicated by the MCOT indication information, adopting a second type LBT.

In one embodiment, determining the transmission parameters for the automatic uplink transmission includes: in the case that the automatic uplink transmission adopts the second type of LBT, determining the LBT priority class adopted by the downlink transmission of the current maximum channel occupation time MCOT according to the LBT information indicated by the cell public indication information C-PDCCH, determining the time length of the automatic uplink transmission according to the LBT priority class, and/or determining the service type QCI of the automatic uplink transmission according to the LBT priority class.

In one embodiment, determining the parameters for automatic uplink transmission includes: under the condition that the automatic uplink transmission adopts the second type of LBT, determining the LBT priority class which can be adopted for the automatic uplink transmission in the current maximum channel occupation time MCOT according to the LBT information indicated by the cell public indication information C-PDCCH, and/or determining the time length of the automatic uplink transmission according to the LBT priority class.

According to another aspect of the present disclosure, there is provided a user equipment UE, comprising: an acquisition unit configured to acquire listen-before-transmit LBT information; a determining unit configured to determine an LBT parameter according to the LBT information and determine a transmission parameter for automatic uplink transmission; and an LBT operation unit configured to perform an LBT operation according to the determined LBT parameter, and determine whether or not a signal can be transmitted on the automatic uplink transmission resource based on the transmission parameter.

According to another aspect of the present disclosure, a method performed by a base station is provided. The method comprises the following steps: configuring listen-before-send (LBT) information and/or resources for automatic uplink transmission for User Equipment (UE); and transmitting the LBT information to the user equipment UE. Preferably, the LBT information may be transmitted to the UE through the cell common indication information C-PDCCH or through higher layer signaling.

In one embodiment, the base station configures the energy detection threshold for automatic uplink transmission and scheduling-based uplink transmission of the UE independently.

In one embodiment, the base station configures the window size CWS for automatic uplink transmission and scheduling-based uplink transmission of the UE, independently or partially independently.

In one embodiment, the base station isAutomatic uplink transmission and scheduling-based uplink transmission of UE, and maximum value CW of continuous use collision window CW is independently configured _max，p Number K of times (f).

In one embodiment, the collision window size CWS of the uplink transmission of the UE is determined according to the ACK/NACK indication corresponding to the reference uplink subframe.

In one embodiment, the reference uplink subframe of the automatic uplink transmission collision window size CWS adjustment of the UE is the first subframe in the first uplink burst based on the first type LBT of at least X subframes before the uplink subframe to be transmitted by the UE.

In one embodiment, a base station configures resources for automatic uplink transmission for a UE, and configures LBT priority class classification information corresponding to the transmission resources.

In one embodiment, the base station instructs the UE on the LBT priority class employed for downlink transmission of the current maximum channel occupancy time MCOT.

In one embodiment, the base station instructs the UE to perform LBT priority classification that may be used for automatic uplink transmission within the current maximum channel occupancy time MCOT.

In one embodiment, the base station indicates the UE through the activated downlink control signaling for LBT priority class information of all HARQ processes automatically transmitted in uplink.

In one embodiment, the base station indicates LBT priority class information of the HARQ process corresponding to the automatic uplink transmission of the UE by scheduling the UL grant transmitted automatically, or by dynamically scheduling the UL grant, or by indicating downlink control information of ACK/NACK.

In one embodiment, the base station triggers/deactivates the automatic uplink transmission by activating/deactivating the downlink control signaling, and the UE will attempt to successfully complete the LBT transmission activation/deactivation determination signaling in the first uplink subframe available for automatic uplink transmission within a predefined time window based on the received activation/deactivation signaling.

In the technical scheme of the disclosure, when carrier monitoring before signal transmission is performed, directional carrier monitoring is performed, so that interference to other nodes of an unlicensed frequency band is avoided, and system gain is improved.

According to yet another aspect of the present disclosure, a method of configuring and activating or deactivating automatic uplink transmission is provided. The base station transmits automatic uplink transmission activation/deactivation indication signaling on a specific type of carrier and/or receives automatic uplink transmission activation/deactivation acknowledgement indication signaling on a specific type of carrier.

In one embodiment, the automatic uplink transmission activation/deactivation indication signaling may activate/deactivate automatic uplink transmission on the same carrier as the signaling is transmitted or on a different carrier.

In one embodiment, the automatic uplink transmission activation/deactivation acknowledgement indication signaling is transmitted in an uplink subframe within a predefined time window.

In one embodiment, the automatic uplink transmission activation/deactivation acknowledgement indication signaling employs an LBT type faster than PUSCH carrying data.

The technical scheme of the present disclosure ensures fairness between automatic uplink transmission LAA UEs and fairness between automatic uplink transmission and scheduling-based LAA UEs. Meanwhile, the technical scheme of the disclosure ensures friendly coexistence of the LAAUE and the UE (such as a WiFi terminal) of other access technologies.

Drawings

The foregoing and other features of the present application will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which:

fig. 1 is a schematic diagram showing a scenario in which licensed and unlicensed bands are jointly networked in a carrier aggregation manner;

FIG. 2 is a diagram showing the conflict window, the maximum occupiable time, and the backoff parameters corresponding to the LBT priority class;

FIG. 3 is a flow chart illustrating a method of automatic uplink transmission according to one embodiment of the present application;

FIG. 4 is a flow chart illustrating configuring automatic uplink transmission according to one embodiment of the present application;

FIG. 5 is a block diagram illustrating a user device according to one embodiment of the present application;

fig. 6 is two schematic diagrams illustrating adjustment of contention window size according to one embodiment of the present application;

fig. 7 is a schematic diagram illustrating adjustment of contention window size according to one embodiment of the present application.

Detailed Description

The disclosure is described in detail below with reference to the drawings and detailed description. It should be noted that the present disclosure should not be limited to the specific embodiments described below. In addition, for the sake of brevity, detailed descriptions of well-known techniques, which are not directly related to the present disclosure, are omitted to prevent confusion of an understanding of the present disclosure.

In the following embodiments of the present disclosure, before the UE performs signal transmission on the unlicensed band, the UE may not wait for the uplink scheduling signaling UL-grant, but select transmission resources on the resources for automatic uplink transmission to transmit the uplink signal. LBT is required before the UE transmits the uplink signal. If LBT is successful, it can be sent, otherwise it cannot be sent.

The resources for automatic uplink transmission are configured by the base station. For example, the time resources for automatic uplink transmission are configured by higher layer signaling. The configuration of the time resource may include a period, for example, a configuration of a semi-persistent transmission SPS of an existing LTE system.

The UE needs to receive an activation signaling (activation) before signaling on the unlicensed band. The activation signaling may be physical layer signaling, such as SPS activation signaling in an LTE system. The frequency domain resource and the starting point of the time resource which are sent by the automatic uplink are indicated in the activation signaling.

If the UE sent the uplink signal but the base station did not demodulate correctly, the UE will send the uplink signal again. For convenience of description, it is referred to as retransmission. However, this embodiment does not limit the retransmission or new transmission of the identifier when the UE retransmits, nor does it limit the RV version adopted by the UE. The retransmission also requires LBT. The retransmission may be sent by way of automatic uplink transmission.

Fig. 3 is a flow chart illustrating a method of automatic uplink transmission according to one embodiment of the present application.

In step 301, the ue acquires listen before transmit LBT information.

For example, the UE may acquire LBT information through the cell common indication information C-PDCCH. Alternatively, the UE may also acquire LBT information by activating signaling that is automatically sent uplink. Alternatively, the UE may also acquire LBT information through higher layer signaling. Alternatively, the cell common indication information C-PDCCH and the higher layer signaling may each include a part of LBT information, and the UE obtains the LBT information from both the cell common indication information C-PDCCH and the higher layer signaling.

In step 302, the ue determines LBT parameters according to the LBT information and determines transmission parameters for automatic uplink transmission. Several examples of UE determination of LBT parameters are discussed in detail below.

Since the automatic uplink transmission may be subject to different interference than the scheduling-based uplink transmission, for example, the probability of collision of the automatic uplink transmission is greater than the scheduling-based uplink transmission. Also, the mechanism for determining whether the uplink transmission is successfully received by the base station may be different from the uplink transmission based on the scheduling, for example, the automatic uplink transmission may be based on the displayed ACK/NACK indication, and thus the determination manners of the LBT parameters of the two scheduling manners may be different. For example, the LBT parameters may be determined according to one or more of the following:

(1.1) the automatic uplink transmission and the energy detection threshold value of the scheduling-based uplink transmission are independently configured.

When LAAUE uplink transmission is performed with CCA detection, whether the detected channel energy exceeds a threshold X or not is determined _Thresh It is determined whether the channel is idle. Wherein X is _Thresh Not exceeding maximum energy detection threshold X _{Thresh_max} . In one way, the X _{Thresh_max} Configured by higher layer signaling. Then the base station configures X for automatic uplink transmission and scheduling-based uplink transmission, respectively _{Thresh_max} . Alternatively, the X _{Thresh_max} X 'obtained by calculation of maximum transmission power of UE' _{Thresh_max} And relative to X 'for higher layer signaling configuration' _{Thresh_max} Offset determination of (2)And (5) setting. Then, the base station configures the offset for the automatic uplink transmission and the scheduling-based uplink transmission, respectively.

(1.2) automatic uplink transmission and UL-grant based uplink transmission, CWS adjustment is completely or partially independent. For example, one of the following may be possible:

for uplink transmission of the same HARQ process, the transmitting end and/or the receiving end maintains CWS, respectively, if there is a mixed use of automatic uplink transmission and UL-grant based.

For example, if the same data is transmitted automatically as an initial transmission and retransmitted as UL-grant based transmission, the automatic transmission and UL-grant based transmission maintain CWS separately. The ACK/NACK of the automatically transmitted PUSCH (indicated ACK/NACK which may be indicated by displayed or indicated ACK/NACK which is indicated by NDI of the UL-grant as in the prior art. That is, the subframes where the two uplink transmissions are located cannot be used as reference subframes for the other party to adjust the CWS.

Based on UL-grant scheduling, it can be further subdivided into DCI scrambled by C-RNTI, for example, based on dynamic UL-grant scheduling, and UL-grant scheduling for automatic uplink transmission, DCI scrambled by X-RNTI, for example, where active DCI for automatic uplink transmission is scrambled by X-RNTI. The X-RNTI may be newly defined or the semi-persistent scheduling SPS C-RNTI may be reused. Preferably, the CWS is maintained for the automatic uplink transmission and the uplink transmission based on the dynamic UL-grant scheduling, but the uplink of the UL-grant scheduling for the automatic uplink transmission maintains the same set of CWS as the automatic uplink transmission.

For uplink transmission of the same HARQ process, if there is a mixed use of automatic uplink transmission and UL-grant based uplink transmission, ACK/NACK corresponding to automatic uplink transmission is available for CWS adjustment of uplink transmission based on UL-grant scheduling, but ACK/NACK corresponding to uplink transmission based on UL-grant scheduling is not available for CWS adjustment of automatic uplink transmission. Further, the ACK/NACK corresponding to the automatic uplink transmission based on the LBT of the first type may be used for CWS adjustment of the uplink transmission based on UL-grant scheduling, but the ACK/NACK corresponding to the uplink transmission based on UL-grant scheduling may not be used for CWS adjustment of the uplink transmission of the automatic uplink transmission.

Preferably, ACK/NACK corresponding to automatic uplink transmission based on LBT of the first type and/or uplink transmission of UL-grant scheduling for automatic uplink transmission may be used for CWS adjustment based on uplink transmission of dynamic UL-grant scheduling, but ACK/NACK corresponding to uplink transmission based on UL-grant scheduling may not be used for uplink transmission of automatic uplink transmission and/or CWS adjustment corresponding to uplink transmission of UL-grant scheduling for automatic uplink transmission.

For uplink transmission of the same HARQ process, if there is a mixed use of automatic uplink transmission and UL-grant based uplink transmission, ACK/NACK corresponding to automatic uplink transmission is not available for CWS adjustment of uplink transmission based on UL-grant scheduling, but ACK/NACK corresponding to uplink transmission based on UL-grant scheduling is available for CWS adjustment of automatic uplink transmission. Further, the ACK/NACK corresponding to the automatic uplink transmission is not available for CWS adjustment of uplink transmission based on UL-grant scheduling, but the ACK/NACK corresponding to uplink transmission based on the UL-grant scheduling and based on the LBT of the first type is available for CWS adjustment of automatic uplink transmission.

Preferably, the ACK/NACK corresponding to the automatic uplink transmission and/or the uplink transmission of the UL-grant schedule for the automatic uplink transmission is not used for CWS adjustment of the uplink transmission based on the dynamic UL-grant schedule, but the ACK/NACK corresponding to the uplink transmission based on the UL-grant schedule and based on the LBT of the first type is used for the automatic uplink transmission and/or the CWS adjustment corresponding to the uplink transmission of the UL-grant schedule for the automatic uplink transmission.

For uplink transmission of the same HARQ process, if there is a mixed use of automatic uplink transmission and UL-grant based uplink transmission (X-RNTI scrambling) of automatic uplink transmission or UL-grant scheduling for automatic uplink transmission, the CWS of dynamic transmission of the UL grant scheduling based on Y-RNTI scrambling is independent or partially independent. The automatic uplink transmission is activated by adopting X-RNTI scrambling (the X-RNTI can be newly defined or the SPS C-RNTI of the existing standard can be reused), the automatic uplink transmission retransmission is scheduled by the UL grant scrambled by the X-RNTI, or the automatic uplink transmission retransmission is triggered by DCI (which can simultaneously contain HARQ process information) carrying the ACK/NACK indication. Obviously, when determining the CWS of the X-RNTI scrambled UL grant scheduled PUSCH, it may be determined according to the value of NDI of the UL grant, for example ndi=1 indicates retransmission, CWS is increased, for example, if DCI indicates NACK, CWS of the retransmitted PUSCH that is automatically uplink transmitted is increased, and if ACK, CW of the retransmitted PUSCH that is automatically uplink transmitted is reset. But for PUSCH scheduled based on Y-RNTI scrambled UL grant for one HARQ process, e.g. Y-RNTI is C-RNTI for dynamic scheduling, and the last transmission of this HARQ process is either scheduled by X-RNTI scrambling or automatic uplink transmission, then the adjustment of CWS of LBT of Y-RNTI scrambled UL grant scheduled PUSCH is not referenced if the last transmission was successful. For example, the adjustment of the CWS is not determined according to the value of the NDI of the Y-RNTI scrambled UL grant. In one implementation, the last transmission is scheduled by X-RNTI scrambling or is an automatic uplink transmission, not as a Y-RNTI scrambled UL grant scheduled PUSCH CWS-adjusted reference subframe. The PUSCH scheduled by the UL grant scrambled by the Y-RNTI last time can be found continuously, the NDI of the last UL grant is compared with the NDI of the current UL grant, if flipped, the CWS is reset, otherwise the CWS is increased. This has the advantage that in an actual system, if the previous scheduling is an automatic uplink transmission or an X-RNTI scrambled based transmission, the current occurrence of Y-RNTI scrambled UL grant is considered that this HARQ process has scheduled a new transport block, regardless of the value indicated by NDI. But it is likely that the last transmission of this HARQ process was not successful. The method for determining the NDI value of the Y-RNTI scrambled UL grant is often different from the method for determining the NDI value of the X-RNTI UL grant. Therefore, it cannot be determined whether the last transmission was successful by comparing the values of the two.

(1.3) maximum value CW of continuous use Collision Window (CW) of automatic uplink transmission and scheduling-based uplink transmission _max，p Is independently configured.

When the LAA UE uplink transmission carries out the first type of LBT, the maximum value and the minimum value of the CW are determined according to the LBT priority class and respectively recorded as the CW _max，p And CW _min，p . Wherein, if K times are consecutive, the length CW of the conflict window _p ＝CW _max，p Length CW of the window _p Reset, CW _p ＝CW _min，p . The base station configures K for uplink transmission of automatic uplink transmission and uplink transmission based on scheduling respectively, denoted as K1 and K2 respectively.

For example, the UE has two HARQ processes. Where HARQ process 1 is UL-grant scheduling based and another HARQ process 2 is automatic uplink transmission. Then the CWS of the two HARQ processes are maintained independently and K1 and K2 are configured separately.

(1.4) determining the size of the CWS according to the ACK/NACK transmitted in the uplink of the reference subframe.

Preferably, the ACK/NACK is an ACK/NACK indicated by a display carried by physical layer signaling. For example, a (UE-group based) DCI based on a user group indicates ACK/NACKs of a plurality of UEs.

The uplink transmission may be only automatic uplink transmission and/or uplink transmission of UL-grant scheduling for automatic uplink transmission, or the uplink transmission may be automatic uplink transmission, uplink transmission of UL-grant scheduling for automatic uplink transmission, or uplink transmission based on dynamic UL-grant scheduling.

Preferably, if at least one of the uplink transmissions of the reference subframe is an ACK, the CWS of all LBT priorities of the uplink transmissions are reset. Otherwise, for example, the uplink transmission of the reference subframe is NACK, or the UE does not receive any ACK/NACK indication (may be DCI indicating ACK/NACK, or a retransmission or newly transmitted UL-grant for scheduling the uplink transmission of the reference subframe), then the CWS of all LBT priorities increases. Wherein the reference subframe is subframe n where the ACK/NACK indication corresponding to the last transmission of the uplink transmission of which the CWS adjustment needs to be determined ₀ The last uplink transmission burst based on the first type LBT of at least 4 subframes further forward (the end subframe of the uplink burst is no later than subframe n) ₀ -4) the first subframe.

Preferably, the ACK/NACK indication of the reference subframe is earlier than an uplink subframe for which CWS adjustment is determined based on the reference subframe, and the time difference from the uplink subframe for which CWS adjustment is determined based on the reference subframe is not less than an X subframe.

As shown in fig. 6 (a), it is assumed that the uplink HARQ process #1 and the uplink HARQ process #3 are transmitted in the subframes n-9 and n-7, respectively using the second type LBT and the first type LBT. In subframes n and n+1, the ue receives NACK for HARQ process #1 and ACK for process #3, respectively. The UE attempts retransmission at the location corresponding to HARQ process #1 and newly transmits at the location of HARQ process # 3. Then, the CWS sent by the uplink of the HARQ process #1 may determine the reference subframe according to the first uplink subframe sent by the first type LBT and found forward of the downlink subframe n where the ACK/NACK indication of the HARQ process #1 is located. The reference subframe is subframe n-7, wherein the transmitted HARQ process #3 is successfully transmitted, and the base station transmits ACK in subframe n+1. Therefore, the CWS of the uplink transmission of subframe n+7 resets.

As further shown in fig. 6 (b), it is assumed that the uplink HARQ process #1 and the uplink HARQ process #3 are transmitted in the subframes n-9 and n-7, and the second type LBT and the first type LBT are adopted respectively. In subframe n, the UE receives NACK for HARQ process # 1. The UE attempts retransmission at the location corresponding to HARQ process # 1. Then, the CWS sent by the uplink of the HARQ process #1 may determine the reference subframe according to the first uplink subframe sent by the first type LBT and found forward of the downlink subframe n where the ACK/NACK indication of the HARQ process #1 is located. The reference subframe is subframe n-7. Since the UE has not received the ACK/NACK indication for HARQ process #3 transmitted by subframe n-7, the UE increases the CWS for the uplink transmission of subframe n+7. It can be seen that although the uplink transmission of HARQ process #3 is successfully received by the base station, the UE can only increase CWS since the base station does not feedback ACK in time, but feeds back ACK in downlink subframe n+8.

(1.5) the reference subframe for CWS adjustment of automatic uplink transmission is an uplink subframe n earlier than the one to be automatically uplink transmitted by the UE ₀ And the time difference with the uplink subframe is at least not less than the first uplink burst of the X subframe occupying the channel through the LBT of the first type (the ending subframe of the uplink burst is not later than subframe n ₀ -X) a first uplink subframe.

Unlike uplink transmission triggered by DCI based on UL-grant scheduling or based on ACK/NACK feedback, the automatic uplink transmission described herein refers to DCI in which UL-grant scheduling or ACK/NACK feedback is not received for a period of time. For example, when the base station activates SPS transmission, the UE does not have traffic to transmit, and the UE does not transmit uplink data. Over time, when a new data packet arrives, the UE may perform automatic uplink transmission on the activated SPS resources. Or after the UE successfully transmits a group of data packets, the UE will stop transmitting data without data to be transmitted in the buffer. Over time, when a new data packet arrives, the UE may perform automatic uplink transmission on the activated SPS resources. Or in the new transmission or retransmission based on the timer, the UE does not receive any downlink control signaling for triggering the UE to perform the new transmission or retransmission within a predefined time window, and then the UE may perform automatic uplink transmission on the corresponding SPS resource after the time window is over.

For the automatic uplink transmission described above, the UE needs to determine the CWS size. Then the reference subframe is subframe n in which the UE intends to perform automatic uplink transmission ₀ The first of the preceding at least X subframes occupies an uplink burst of the channel by LBT of the first type (the end subframe of the uplink burst is no later than subframe n ₀ -X) a first uplink subframe. Preferably, X is a predefined value, for example x=4.

(1.6) if the UE attempts uplink transmission but cannot transmit in at least one uplink subframe in the uplink burst in which the reference subframe is located, the CWS is unchanged.

The first uplink burst may include one or more consecutive uplink subframes.

The first uplink burst can be only an uplink burst based on dynamic UL-grant scheduling, or can be only an uplink burst based on dynamic UL-grant scheduling or UL-grant scheduling for automatic uplink transmission, or can be any uplink burst, including an uplink burst that can be automatic uplink transmission.

(1.7) if there are at least two CWS adjustments based on the uplink subframes transmitted automatically uplink corresponding to the same reference subframe, adjusting the CWS of the first uplink subframe according to whether the reference subframe is correctly received by the base station, and the CWS of the subsequent uplink subframe has the same value as the CWS of the first uplink subframe.

As shown in fig. 7, it is assumed that the period of automatic uplink transmission is 2ms, and there are two HARQ processes. Assuming that the uplink HARQ process #1 and the uplink HARQ process #2 are transmitted in the subframes n-9 and n-7, a second type LBT and a first type LBT are adopted respectively. In subframes n and n+1, the ue receives the ACK for HARQ process #1 and the NACK for HARQ process # 2. The UE attempts a new transmission at a location corresponding to HARQ process #1, and a retransmission at a location corresponding to HARQ process # 2. Then, the CWS sent by the uplink of the HARQ process #1 may determine the reference subframe according to the first uplink subframe sent by the first type LBT and found forward of the downlink subframe n where the ACK/NACK indication of the HARQ process #1 is located. The reference subframe is subframe n-7. The CWS of the uplink transmission of the HARQ process #2 may determine the reference subframe according to the first uplink subframe based on the first type LBT transmission found forward of the downlink subframe n+1 where the ACK/NACK indication of the HARQ process #2 is located. The reference subframe is also subframe n-7. Then, since the corresponding NACK subframe n+1 was received for the uplink transmission of subframe n-7, the CWS for the uplink transmission of subframe n+7 increases, while the CWS for subframe n+9 is the same as the CWS for subframe n+7.

(1.8) automatic uplink transmission, or LBT priority of uplink transmission based on UL-grant scheduling for automatic uplink transmission, may be determined by one or more of the following ways:

when there are multiple HARQ processes available, the LBT priority of all processes may be indicated by one activation DCI. The LBT priority is determined by the lowest LBT priority (the highest index number of LBT priority class) among all HARQ processes.

When there are multiple HARQ processes available, the LBT priority of all processes may be indicated by one activation DCI. The indicated LBT priority is determined by the highest LBT priority (lowest index number of LBT priority class) among all HARQ processes. The LBT priority employed in each HARQ process may not be limited to the indicated LBT priority, but may not be higher.

-based on the UL-grant for automatic uplink transmission, when scheduling retransmissions or new transmissions, a new LBT priority may be indicated, overriding the LBT priority indicated in the activation DCI.

-in the DCI indicating an ACK/NACK, not only the HARQ process index, but also the new LBT priority of the HARQ process, overriding the LBT priority indicated in the activate DCI.

-upon new transmission or retransmission based on dynamic UL-grant scheduling, a new LBT priority may be indicated, overriding the LBT priority indicated in the active DCI.

Preferably, the automatic-based uplink transmission employs only the first type of LBT, and does not employ the second type of LBT. When the UE receives the MCOT indication information and the uplink subframe to be automatically transmitted by the UE is positioned in the uplink subframe set indicated by the MCOT indication information, the UE still only adopts the first type LBT. The uplink subframe set indicated by the MCOT indication information may be determined according to the "LAA uplink configuration" bit field in the C-PDCCH of the Rel-14LAA, that is, by "uplink offset" and "uplink duration UL duration".

Preferably, the uplink transmission based on the automatic uplink transmission may use the first type LBT or the second type LBT.

When the UE receives the MCOT indication information and the uplink subframe to be automatically transmitted by the UE is located in the uplink subframe set indicated by the MCOT indication information, the UE may use the second type LBT.

Preferably, if the automatic uplink transmission of the UE adopts the second type LBT, after the LBT is successful, if the UE continuously transmits k subframes without intervals between the subframes, the k subframes must all be located in the uplink subframe set indicated by the MCOT indication information. If some of the k subframes are located outside the uplink subframe set indicated by the MCOT indication information, only the first type LBT can be performed, or subframes located outside the uplink subframe set indicated by the MCOT indication information need to be performed again.

Preferably, if the UE uses the first type of LBT for the automatic uplink transmission, after the LBT is successful, if the UE continuously transmits k subframes, the k subframes are continuous in the subframe dimension but have an interval between subframes, for example, the UE continuously transmits 4 subframes, but the last symbol and/or the first symbol of each subframe is null. Then, a second type of LBT may be performed for these subframes within the MCOT determined by the UE performing the first type of LBT.

In another embodiment, when the UE intends to make an automatic uplink transmission, the UE may determine the transmission parameters based on the type of LBT and/or LBT priority class according to one or more of the following manners. The transmission parameter may be a newly transmitted transmission parameter or a retransmitted transmission parameter. For example, the transmission parameter may be a time parameter of a resource for uplink transmission, or a frequency domain parameter, or an indication of whether uplink transmission is possible, or a service type of uplink transmission, etc.

When the transmission parameter is an indication of whether uplink transmission is possible, whether uplink transmission is possible may be determined according to the following two ways:

(2.1) determining whether a signal can be transmitted on a resource for automatic transmission according to the type of LBT.

It is assumed that whether the UE transmits a signal on the resource for automatic transmission is compared with a set threshold according to a random number generated by the UE. If the random number exceeds a predefined threshold, it may be sent, otherwise it may not be sent (of course, if LBT fails, it cannot be sent). Then, thresholds Thr1 and Thr2 may be configured for the first type LBT and the second type LBT, respectively, where Thr1 is lower than Thr2, so that the probability that the random number generated by the UE is greater than Thr1 is greater than the probability that the random number is greater than Thr 2. Thus, the number of UEs based on the first type LBT attempting to transmit an uplink signal for automatic uplink transmission is greater than the number of UEs based on the second type LBT attempting to transmit an uplink signal for automatic uplink transmission within the same subframe. Alternatively, the same threshold is used for both the first type LBT and the second type LBT, but the UE uses the type LBT as a weighting factor when generating the random number, so that the UE of the first type LBT generates a larger random number with a larger probability. The method is also applicable to determining resources to be automatically sent in uplink in other modes.

The method can reduce the possibility of selecting to perform automatic uplink transmission on the same resource, and reduce the collision probability among the LBT UEs of the second class based on the number of the LBT UEs of the second class. Since each UE based on the second type LBT, which selects to attempt to transmit the uplink signal for automatic uplink transmission in the same subframe, performs 25us LBT at the same location, cannot find the other party, the collision probability between each UE is high. And each UE based on the first type LBT, which selects to try to send the uplink signal of automatic uplink transmission in the same subframe, can further reduce the collision among each UE through different CWS.

(2.2) determining whether a signal can be transmitted on a resource for automatic transmission according to the LBT priority class.

If the UE transmits a signal on the resource for automatic transmission, the signal is compared with a set threshold according to a random number generated by the UE, if the random number exceeds a predefined threshold, the signal can be transmitted, otherwise, the signal cannot be transmitted (of course, if LBT fails, the signal cannot be transmitted). Then, the thresholds may be respectively configured for different LBT priority class, for example, the thresholds may be respectively set for the 4 LBT priority classes in table 1, or the k (k < 4) thresholds may be respectively set for one or more LBT priority classes, and the threshold corresponding to the higher LBT priority may be set lower, so that the traffic with the higher LBT priority may be sent with a greater probability, so as to ensure that the traffic with the higher QCI is timely transmitted with a lower collision. Alternatively, there is only one threshold, but the UE classifies the LBT priority as a weighting factor when generating the random number, so that higher LBT priority UEs generate larger random numbers with a greater probability.

The method is particularly suitable for the UE adopting the second type LBT. Because of the second type of LBT, LBT priority classification is not differentiated, and 25us LBTs are all performed at the same location. Thus, it may occur that traffic with a higher QCI collides with traffic with a lower QCI. The method reduces the influence of the service with lower QCI on the service with higher QCI by setting a lower threshold for the service with higher QCI (namely, the service with lower LBT priority class value is smaller).

Similarly, the time parameter of the resource for automatic uplink transmission may be determined according to the method (2.1) or (2.2).

And when the transmission parameters are time or frequency domain parameters of the automatic uplink transmission resources, the UE determines according to the configuration information of the base station. The configuration information may include LBT priority class information corresponding to the resource sent by the automatic uplink. The UE may determine resources for automatic uplink transmission according to LBT priority classifications for automatic uplink transmissions to be transmitted.

When the transmission parameter is a time length and/or a service type of automatic uplink transmission, the transmission parameter may be determined according to one of the following manners:

(3.1) if the automatic uplink transmission of the UE adopts the second type LBT, the UE can determine, through the indication information of the base station, the LBT priority class adopted when the base station transmits the downlink transmission in the current MCOT, and the UE determines the UE uplink transmission parameter (for example, the transmittable subframe length) according to the LBT priority class, where the QCI of the service actually transmitted by the UE is determined by the UE. In determining the subframe length, the UE needs to ensure that the subframe length does not exceed the minimum number of subframes required to transmit all traffic with the same or lower index (i.e., higher LBT priority) than the LBT priority class. Or, the UE determines the uplink transmission parameters of the UE according to the LBT priority classification: the length of the subframe that can be transmitted, and the QCI of the traffic that the UE actually transmits. I.e. the LBT priority class index corresponding to the QCI of the traffic actually transmitted by the UE cannot exceed the LBT priority class index. The indication information of the base station can be carried through a cell public signaling C-PDCCH, namely, LBT priority classification adopted when the indication is sent to downlink transmission in the current MCOT in the C-PDCCH.

(3.2) if the automatic uplink transmission of the UE adopts the second type LBT, the UE may determine, through the indication information of the base station, an LBT priority class that may be adopted in uplink transmission in the current MCOT, and the UE determines, according to the LBT priority class, a subframe length that may be transmitted, or further determines an LBT priority class that may be used in automatic uplink transmission using the second type LBT. In determining the subframe length, the UE needs to ensure that the subframe length does not exceed the minimum number of subframes required to transmit all traffic with the same or lower index (i.e., higher LBT priority) than the LBT priority class.

(3.3) when the UE receives the mcot_1 indication information and the cut-off symbol information indicating downlink transmission, and the uplink subframe to be automatically transmitted by the UE is located in the mcot_1, and the uplink subframe to be automatically transmitted by the UE is immediately adjacent to the cut-off subframe indicating downlink transmission or is the same subframe as the cut-off subframe indicating downlink transmission, if the UE can complete the second type LBT after the cut-off symbol indicating downlink transmission, the UE can start to transmit the automatic uplink transmission from 25us after the cut-off symbol indicating downlink transmission, otherwise, only the first type LBT can be performed. If the continuous multi-subframe transmission is performed, the uplink subframe continuously transmitted should belong to the MCOT_1.

For example, the base station selects one downlink carrier X for Cat-4LBT among the multiple downlink carriers and performs 25us LBT on the other carriers Y, Z (i.e., type B LBT for multiple carriers, such as TS 36.213.15.1.5.2). Assuming that LBT of downlink carrier X succeeds in subframe 0 and LBT of downlink carrier Y succeeds, then the base station may share MCOT with UEs served by the base station on carriers X and Y, assuming mcot=4 ms, that is, between subframes 0 to 3, if there is an uplink subframe, the uplink subframe belongs within MCOT. For carrier Y, we call the shared MCOT 1 (mcot_1 and MCOT are the same length). On carrier X, a second type LBT may be used for all uplink transmissions in the MCOT. On carrier Y, the uplink transmission may employ the second type LBT if and only if the interval between the uplink transmission and the downlink transmission in the MCOT is 25us or less, otherwise the uplink transmission must employ the first type LBT even in the MCOT. It is assumed that the base station transmits downlink transmissions starting from subframe 0 until the 3 rd symbol of subframe 2 is cut off. MCOT_1 has a length of 4. Suppose subframe 2 is an automatic uplink transmission resource subframe. Then the UE may start the second type LBT, i.e. 25us CCA, from the 4 th symbol according to the downlink time (DL timing), and if the channel is idle, the UE may start sending an automatic uplink transmission uplink signal from 25us after the 4 th symbol of subframe 2, i.e. from (25+ta) us of the 4 th symbol of subframe 2 according to the uplink time (UL timing), wherein TA (timing advance) is the uplink time advance.

In step 303, the ue performs an LBT operation according to the determined LBT parameter and determines whether it is possible to transmit a signal on the automatic uplink transmission resource based on the transmission parameter. If the LBT is successful, the UE may transmit an uplink signal on the automatic uplink transmission resource. If LBT fails, the UE gives up transmitting.

Preferably, the automatic uplink transmission resource may be configured by a base station. For example, it may be configured by higher layer signaling and/or by physical layer trigger signaling. The automatic uplink transmission resource may include: the time-frequency resources (e.g., period, time offset, PRB resources, or bandwidth portion BWP), modulation Coding Scheme (MCS), reference symbol parameters (e.g., reference symbol sequence, or orthogonal codeword OCC, or Cyclic shift) for uplink transmission. In addition, the automatic uplink transmission resource may further include other necessary information, for example, redundancy version information (RV), the number of repeated transmissions K, and the like. See configuration in

step

401, 402.

Preferably, after the UE performs automatic uplink transmission according to step 303, the UE receives HARQ-ACK feedback for the automatic uplink transmission on a downlink carrier of a specific type.

Preferably, the specific type of downlink carrier is Pcell or pSCell.

Preferably, the specific type of downlink carrier is a licensed band carrier, and the licensed band carrier is configured by a base station. For example, the licensed band carrier is the carrier on which the indication information for triggering automatic uplink transmission or indicating automatic uplink transmission failure is transmitted in step 402. For example, the base station is in the licensed band carrier CC ₂ An indication triggering automatic uplink transmission is sent upwards, and the triggering UE can be used for carrying out carrier wave CC in an unlicensed frequency band ₃ If the uplink is automatically sent, the UE is in the CC ₃ After automatic uplink transmission, the uplink transmission will be performed on the CC ₂ And receiving HARQ-ACK feedback.

Preferably, the specific type of downlink carrier is a carrier that activates automatic uplink transmission.

Preferably, the time of receiving the HARQ-ACK feedback is determined by the time of the automatic uplink transmission and a predefined time offset.

Preferably, the HARQ-ACK feedback is carried by a PHICH channel or by a PDCCH. The PDCCH may contain no scheduling information, only HARQ-ACK information, and this PDCCH is common to multiple UEs, with HARQ-ACKs of different UEs occupying different bits in the PDCCH. Preferably, the PDCCH includes HARQ process information of each UE.

Preferably, the UE determines retransmission of automatic uplink transmission or transmits new data according to the received HARQ-ACK feedback.

Preferably, the time when the UE performs retransmission of automatic uplink transmission or transmits new data is determined according to the time of the received HARQ-ACK feedback and a predefined time offset.

Preferably, the UE determines the start point of the time window according to the time of the received HARQ-ACK feedback and a predefined time offset, and determines the end point of the time window according to the length of the predefined time window. The UE performs LBT during this time window, attempting to retransmit the automatic uplink transmission on the automatic uplink transmission resource or transmitting new data. Further, when there are a plurality of HARQ processes, the UE attempts to retransmit the automatic uplink transmission or transmit new data on the automatic uplink transmission resource of the corresponding HARQ process.

Preferably, for the same HARQ process, if the UE receives both the HARQ-ACK feedback and the UL grant, the UE determines PUSCH transmission according to the indication of the UL grant.

Preferably, the PUSCH transmitted by the UE in the automatic uplink includes information related to the HARQ process, for example, the HARQ ID. The indication may be indicated by a displayed bit or indirectly through a DMRS.

Fig. 4 is a flow chart illustrating configuring automatic uplink transmission according to one embodiment of the present application.

In step 401, the base station configures resources for automatic uplink transmission.

The resources for automatic uplink transmission at least comprise time resources. Wherein the configuration of the time resource may comprise a period. The configuration of the time resources may be in the form of a bit map.

Preferably, the resources for automatic uplink transmission may further include frequency domain resources, such as uplink carrier information.

Preferably, the resource for automatic uplink transmission may further include information about the HARQ process corresponding to the automatic uplink transmission resource, for example, HARQ process ID.

Preferably, the resources for the automatic uplink transmission may further include LBT related information, such as LBT priority level, LBT type information, or the like, which may be used for the automatic uplink transmission.

The signaling configured for automatic uplink transmission resources is RRC signaling, or a MAC layer control element CE, or physical layer control information, or a combination of multiple kinds of information. The physical layer control information may include indication information sent by the base station to trigger automatic uplink transmission in step 402. The physical layer control information may be a C-PDCCH.

In step 402, the base station transmits indication information for activating automatic uplink transmission or indicating automatic uplink transmission failure.

Preferably, the indication information is carried through physical layer signaling, such as SPS activation signaling in an LTE system, or SPS deactivation signaling.

Preferably, the indication information may further include LBT related information, for example, LBT priority that may be used for the automatic uplink transmission, or LBT type information, etc.

Preferably, the indication information includes information indicating automatic uplink transmission of frequency domain resources, for example, occupied physical resource block PRB information, or index information of a corresponding uplink carrier.

Preferably, the indication information includes frequency domain resources for indicating the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement information in step 403, for example, physical resource block PRB information occupied by the information, or index information of a corresponding uplink carrier.

Preferably, the PRB information of the automatic uplink transmission frequency domain resource is the same as the PRB information of the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement information.

Preferably, the indication information includes index information indicating an uplink carrier corresponding to the failure of automatic uplink transmission, that is, which uplink carrier fails in automatic uplink transmission.

Preferably, the indication information includes a start point indicating a time resource available for automatic uplink transmission.

Preferably, the base station can only transmit the indication information in the authorized frequency band.

Preferably, the base station can only send the indication information on the primary carrier Pcell or the primary and secondary carriers Pscell.

For example, when the base station transmits a signal for triggering the carrier CC in the unlicensed band ₂ When the automatic uplink transmission instruction signaling is sent, the base station can only send the instruction signaling to the Pcell CC ₁ And sending the indication signaling. The indication signaling comprises carrier indication information, such as CIF of 3 bits, triggering CC ₂ Automatic uplink transmission.

Preferably, when the base station transmits an indication of automatic uplink transmission or automatic uplink transmission failure in an unlicensed frequency band carrier, and the downlink transmission burst in which the indication is located does not include other downlink transmissions, the base station may use LBT of a different type from PDSCH carrying ordinary data or PDCCH scheduling ordinary data. For example, a 25us LBT may be used, or alternatively, the highest priority Cat 4 LBT may be used, e.g., the contention window length CWS may be set to [3,7].

In step 403, the base station receives an indication of an automatic uplink transmission acknowledgement or an automatic uplink transmission failure acknowledgement from the UE on a specific type of uplink carrier.

Preferably, the specific type of uplink carrier is an uplink carrier of a licensed band.

Preferably, the specific type of uplink carrier is a Pcell or a Pscell.

The advantage of the UE sending an indication of an automatic uplink transmission acknowledgement or an automatic uplink transmission failure acknowledgement on the licensed band is that it can be guaranteed to send the indication in a timely manner. If the indication of the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement is transmitted on the unlicensed frequency band, the UE may not successfully complete LBT within a specified time or a specified period due to the busy channel, and thus the indication of the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement may not be transmitted, which makes it unclear to the base station whether the UE has not received the indication information triggering the automatic uplink transmission or indicating the automatic uplink transmission failure or has not successfully occupied the channel.

Preferably, the specific type of uplink carrier is an uplink carrier corresponding to the downlink carrier used for triggering automatic uplink transmission or indicating the indication information of automatic uplink transmission failure in step 402. The corresponding relation is configured by a high-level signaling or defined that the carrier wave where the indication information of the automatic uplink transmission confirmation or the automatic uplink transmission failure confirmation sent by the UE is located and the carrier wave where the indication information for triggering the automatic uplink transmission or indicating the automatic uplink transmission failure is received by the UE are the same carrier wave.

Preferably, the indication information of the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement includes carrier index information, that is, determination indication information indicating which uplink carrier the acknowledgement indication information is. For example, in the above example, the acknowledgement indication information comprises an uplink carrier CC ₂ Is a piece of information of (a).

Preferably, the time-frequency resource occupied by the indication information for transmitting the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement on the specific type of carrier is determined by the indication information for triggering the automatic uplink transmission or indicating the automatic uplink transmission failure in step 402. For example, the time-frequency resource occupied by transmitting the automatic uplink transmission acknowledgement information is the time-frequency resource of the automatic uplink transmission, but the carrier wave may be different. For another example, the frequency domain resource occupied by transmitting the automatic uplink transmission acknowledgement information is configured semi-statically at a higher layer, and the time resource is determined by the automatic uplink transmission indication information, for example, the time resource is an xth subframe after the subframe receiving the automatic uplink transmission indication information.

Preferably, the specific type of uplink carrier is a carrier where automatic uplink transmission is located, i.e. an unlicensed band carrier. In one implementation, a unique transmission subframe of the indication information of the automatic uplink transmission acknowledgement or the automatic uplink transmission failure acknowledgement is determined according to the transmission time of the indication information for triggering the automatic uplink transmission or indicating the automatic uplink transmission failure in step 402. The transmission subframe is a subframe for automatic uplink transmission, for example, a determined first available subframe for automatic uplink transmission according to indication information triggering automatic uplink transmission. In another implementation, to increase the probability of sending the acknowledgement indication information, the UE will perform CCA detection within a time window, attempting to send an indication of an automatic uplink transmission acknowledgement or an automatic uplink transmission failure acknowledgement in the uplink subframe. If the UE cannot send the indication of the automatic uplink sending acknowledgement or the automatic uplink sending failure acknowledgement in the time window, the UE gives up to send the indication. Preferably, the time window uses a subframe where the indication information used for triggering automatic uplink transmission or indicating automatic uplink transmission failure is sent in step 402, or a first available subframe of automatic uplink transmission determined according to the indication information triggering automatic uplink transmission in step 402 as a reference point, and is continuously X _r And the time window is defined as a frame. And in the time window, the UE determines an uplink subframe which can be used for automatic uplink transmission according to the uplink and downlink information indicated by the base station.

Preferably, when the UE transmits an automatic uplink transmission acknowledgement or an automatic uplink transmission failure acknowledgement indication on an unlicensed frequency band carrier, a different type of LBT from PUSCH carrying common data may be used. For example, a 25us LBT may be used, or alternatively, the highest priority Cat 4LBT may be used, e.g., the contention window length CWS may be set to [3,7].

Fig. 5 is a block diagram illustrating a user device according to one embodiment of the present application. As shown in fig. 5, the user equipment UE 500 includes an acquisition unit 510, a determination unit 520, and an LBT operation unit 530.

The acquisition unit 510 is configured to acquire listen before transmit LBT information. For example, the acquisition unit 510 may acquire LBT information through the cell common indication information C-PDCCH. Alternatively, the acquisition unit 510 may acquire LBT information through higher layer signaling. Alternatively, the acquisition unit 510 may also acquire LBT information through both cell common indication information C-PDCCH and higher layer signaling.

The determining unit 520 is configured to determine LBT parameters according to the LBT information and determine transmission parameters for automatic uplink transmission. Specifically, the determining unit 520 may perform the detailed operations described above with respect to step 302 in fig. 3, which are not repeated here.

The LBT operation unit 530 is configured to perform an LBT operation according to the determined LBT parameter, and determine whether or not a signal can be transmitted on the automatic uplink transmission resource based on the transmission parameter. Specifically, the LBT operation unit 530 may perform the detailed operation described above with respect to step 303 in fig. 3, and will not be repeated here.

A program for realizing the functions of the embodiments of the present disclosure may be recorded on a computer-readable recording medium. The corresponding functions can be realized by causing a computer system to read programs recorded on the recording medium and execute the programs. The term "computer system" as used herein may be a computer system embedded in the device and may include an operating system or hardware (e.g., peripheral devices). The "computer-readable recording medium" may be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a recording medium in which a program is stored dynamically at a short time, or any other recording medium readable by a computer.

The various features or functional modules of the apparatus used in the embodiments described above may be implemented or performed by circuitry (e.g., single-chip or multi-chip integrated circuits). Circuits designed to perform the functions described herein may include a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The circuit may be a digital circuit or an analog circuit. Where new integrated circuit technologies are presented as an alternative to existing integrated circuits due to advances in semiconductor technology, one or more embodiments of the present disclosure may also be implemented using these new integrated circuit technologies.

Further, the present disclosure is not limited to the above-described embodiments. Although various examples of the embodiments have been described, the present disclosure is not limited thereto. Fixed or non-mobile electronic devices installed indoors or outdoors may be used as terminal devices or communication devices such as AV devices, kitchen devices, cleaning devices, air conditioners, office devices, vending machines, and other home appliances, etc.

As above, the embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the above-described embodiments, and the present disclosure also includes any design modifications without departing from the gist of the present disclosure. In addition, various modifications can be made to the present disclosure within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the technical scope of the present disclosure. Further, the components having the same effects described in the above embodiments may be replaced with each other.

Claims

1. A method performed by a user equipment, UE, in a wireless communication system, comprising:

acquiring listen-before-send (LBT) related information, wherein the LBT related information comprises information about at least one LBT priority class;

Based on the LBT related information, using the resource for periodic uplink transmission without dynamic scheduling, transmitting at least one Physical Uplink Shared Channel (PUSCH) on a cell associated with an unlicensed frequency band;

receiving Downlink Control Information (DCI) comprising downlink feedback information which explicitly indicates at least one hybrid automatic repeat request (HARQ-Acknowledgement (ACK) feedback corresponding to the at least one Physical Uplink Shared Channel (PUSCH);

determining the at least one HARQ-ACK feedback corresponding to the at least one PUSCH in a reference subframe based on the downlink feedback information; and

and adjusting a conflict window value for uplink transmission based on the LBT related information and the at least one HARQ-ACK feedback.

2. The method of claim 1, wherein the resources for periodic uplink transmissions without dynamic scheduling are configured via higher layer signaling.

3. The method of claim 1, wherein, in case the at least one HARQ-ACK feedback comprises at least one ACK corresponding to the at least one PUSCH in the reference subframe, a collision window value for each LBT priority class is set to a minimum value based on the LBT related information.

4. The method of claim 1, wherein a collision window value for each LBT priority class is increased to a next higher allowed value based on the LBT related information in case the at least one HARQ-ACK feedback does not include any ACK corresponding to the at least one PUSCH in the reference subframe.

5. The method of claim 1, further comprising: an LBT operation is performed based on the LBT related information and the adjusted collision window value.

6. The method of claim 5, further comprising: and transmitting an uplink signal on a cell associated with the unlicensed band based on the performed LBT operation.

7. The method of claim 1, wherein the DCI is for a UE group including the UE.

8. A user equipment, UE, in a wireless communication system, comprising:

a memory; and

at least one processor configured to:

9. The UE of claim 8, wherein the resources for periodic uplink transmissions without dynamic scheduling are configured via higher layer signaling.

10. The UE of claim 8, wherein, in the case where the at least one HARQ-ACK feedback includes at least one ACK corresponding to the at least one PUSCH in the reference subframe, a collision window value for each LBT priority class is set to a minimum value based on the LBT related information.

11. The UE of claim 8, wherein a collision window value for each LBT priority class is increased to a next higher allowed value based on the LBT related information in case the at least one HARQ-ACK feedback does not include any ACK corresponding to the at least one PUSCH in the reference subframe.

12. The UE of claim 8, wherein the at least one processor is further configured to: an LBT operation is performed based on the LBT related information and the adjusted collision window value.

13. The UE of claim 12, wherein the at least one processor is further configured to: and transmitting an uplink signal on a cell associated with the unlicensed band based on the performed LBT operation.

14. The UE of claim 8, wherein the DCI is for a UE group comprising the UE.