WO2019157739A1

WO2019157739A1 - User equipment and method of wireless communication of same

Info

Publication number: WO2019157739A1
Application number: PCT/CN2018/076881
Authority: WO
Inventors: Hai Tang; Huei-Ming Lin
Original assignee: Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Priority date: 2018-02-14
Filing date: 2018-02-14
Publication date: 2019-08-22
Also published as: CN111492708B; CN111492708A

Abstract

A user equipment includes a memory and a processor coupled to the memory. The processor is configured to perform a wireless communication directly over a sidelink interface to at least one second user equipment, monitor and read at least one sidelink resource used by the at least one second user equipment, determine a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs), perform a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources, and transmit the sidelink data TBs using booked second sidelink resources and reserve a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.

Description

USER EQUIPMENT AND METHOD OF WIRELESS COMMUNICATION OF SAME

BACKGROUND OF DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to the field of communication systems, and more particularly, to a user equipment and a method of wireless communication of same.

2. Description of the Related Art

In long term evolution (LTE) radio access technology, current sidelink mode 4 operation involves that a transmitting user equipment (Tx UE) selects radio resources autonomously on its own within a sidelink resource pool for packet data transmissions. In such operation, multiple UEs contend for same set of resources without any central control. Although, most of UEs under current sidelink mode 4 operation are required to perform resource sensing before selection and re-selection of resources for transmission, there is still no guarantee that the selected resources from one UE may not collide with transmission from another UE, when both of the UEs select the same resource. Furthermore, even when two UEs select the same resource for transmission, the two UEs cannot detect such Tx collision as the two UEs are not able to transmit and receive at the same time on the same carrier due to half-duplex limitation. Furthermore, there is also no mechanism for UE feedback such as from a third UE to report an occurrence of a collision.

In future 5th generation new radio (5G-NR) system, there are even more increasing needs for urgent transmission of data over sidelink/PC5 interface to support public safety, road safety and mission critical communications. Data latency requirement for end-to-end communication becomes extremely short and at the same time these applications and use cases demand for even higher reliability of message being delivered without error. As an example of fully driverless operation such as autonomous driving, fast and reliable communication between closed-by vehicles is crucial for safe driving and maneuver on the road. For the existing LTE-sidelink technology, it is very difficult to satisfy these requirements and there is no guarantee that it may meet these requirements due to the resource selection mechanism as described earlier. As the result, this has given the rise to the need to support ultra reliable and low latency communication (URLLC) in a next generation of wireless communication system.

SUMMARY

An object of the present disclosure is to propose a user equipment (UE) and a method of wireless communication of same for providing a resource pre-emption and reservation mechanism for sidelink data transport blocks (TBs) transmissions.

In a first aspect of the present disclosure, a user equipment for wireless communication includes a memory and a processor coupled to the memory. The processor is configured to perform a wireless communication directly over a sidelink interface to at least one second user equipment, monitor and read at least one sidelink resource used by the at least one second user equipment, determine a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs) , perform a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources, and transmit the sidelink data TBs using booked second sidelink resources and reserve a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.

According to an embodiment in conjunction to the first aspect of the present disclosure, the sidelink resources, the first sidelink resources, and the second sidelink resources are at least one of short transmission time interval (sTTI) sidelink resources and normal transmission time interval (nTTI) sidelink resources.

According to an embodiment in conjunction to the first aspect of the present disclosure, the second sidelink resources are empty sidelink resources before performing the pre-emption processes, instead of being used by the at least one second user equipment.

According to an embodiment in conjunction to the first aspect of the present disclosure, each of the sTTI sidelink resources and the nTTI sidelink resources includes a guard period (GP) /automatic gain control (AGC) region, a control region for transmitting a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) , and a data region for at least one of transmitting the pre-emption signals and transmitting a physical sidelink shared channel (PSSCH) for transmitting the sidelink data TBs.

According to an embodiment in conjunction to the first aspect of the present disclosure, the GP/AGC region has one symbol length, and the data region has at least 3 symbols in length.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to sense the GP/AGC region of the first sidelink resource and/or read the control region of the first sidelink resource to determine a true availability of the first sidelink resource for transmitting the pre-emption signals.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to transmit the pre-emption signals in the data region of the first sidelink resource.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to perform a random selection with equal probability of two symbols out of a total number of symbols in the data region of the first sidelink resource for transmitting a pair of pre-emption signals.

According to an embodiment in conjunction to the first aspect of the present disclosure, each pre-emption signal has one symbol length and holds identical information as carried by another pre-emption signal.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to transmit an information content in the pre-emption processes, the information content includes a time offset parameter indicating a time gap in terms of a number of sidelink resources or a number of milliseconds for booking the second sidelink resources, a ProSe per packet priority (PPPP) level, a user equipment source identity, and/or a destination identity.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to reserve the same frequency resources by indicating a time offset in the SCI of the second sidelink resource.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, and the processor is further configured to detect the second pre-emption signals on the first sidelink resources being not overlapped with the pre-emption signals.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to detect the second pre-emption signals having a time gap with the pre-emption signals in a time domain.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals and the second pre-emption signals in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to independently and randomly choose with equal probability with the at least one second user equipment whether or not continue to use the second sidelink resources after the same time period, or abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level greater than the first PPPP level in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level less than the first PPPP level in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to continue to use the second sidelink resources after the same time period.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the second pre-emption signals on the first sidelink resources, detect the second pre-emption signals having a time gap with the pre-emption signals in a time domain, detect a part of the second pre-emption signals being overlapped with a part of the pre-emption signals, and detect another part of the second pre-emption signals being not overlapped with another part of the pre-emption signals.

According to an embodiment in conjunction to the first aspect of the present disclosure, a number of the pre-emption processes is equal to a number of booking the second sidelink resources.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to transmit the data TBs by an initial transmission and at least one re-transmission.

According to an embodiment in conjunction to the first aspect of the present disclosure, the processor is further configured to transmit the data TBs and reserve the same frequency resources repeatedly.

In a second aspect of the present disclosure, a method of wireless communication of a user equipment includes performing a wireless communication directly over a sidelink interface to at least one second user equipment, monitoring and reading at least one sidelink resource used by the at least one second user equipment, determining a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs) , performing a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources, and transmitting the sidelink data TBs using booked second sidelink resources and reserving a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.

According to another embodiment in conjunction to the second aspect of the present disclosure, the sidelink resources, the first sidelink resources, and the second sidelink resources are at least one of short transmission time interval (sTTI) sidelink resources and normal transmission time interval (nTTI) sidelink resources.

According to another embodiment in conjunction to the second aspect of the present disclosure, the second sidelink resources are empty sidelink resources before performing the pre-emption processes, instead of being used by the at least one second user equipment.

According to another embodiment in conjunction to the second aspect of the present disclosure, each of the sTTI sidelink resources and the nTTI sidelink resources includes a guard period (GP) /automatic gain control (AGC) region, a control region for transmitting a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) , and a data region for at least one of transmitting the pre-emption signals and transmitting a physical sidelink shared channel (PSSCH) for transmitting the sidelink data TBs.

According to another embodiment in conjunction to the second aspect of the present disclosure, the GP/AGC region has one symbol length, and the data region has at least 3 symbols in length.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes sensing the GP/AGC region of the first sidelink resource and/or reading the control region of the first sidelink resource to determine a true availability of the first sidelink resource for transmitting the pre-emption signals.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes transmitting the pre-emption signals in the data region of the first sidelink resource.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes performing a random selection with equal probability of two symbols out of a total number of symbols in the data region of the first sidelink resource for transmitting a pair of pre-emption signals.

According to another embodiment in conjunction to the second aspect of the present disclosure, each pre-emption signal has one symbol length and holds identical information as carried by another pre-emption signal.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes transmitting an information content in the pre-emption processes. The information content includes a time offset parameter indicating a time gap in terms of a number of sidelink resources or a number of milliseconds for booking the second sidelink resources, a ProSe per packet priority (PPPP) level, a user equipment source identity, and/or a destination identity.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes reserving the same frequency resources by indicating a time offset in the SCI of the second sidelink resource.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, and detecting the second pre-emption signals on the first sidelink resources being not overlapped with the pre-emption signals.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals and the second pre-emption signals in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and independently and randomly choosing with equal probability with the at least one second user equipment whether or not continue to use the second sidelink resources after the same time period, or abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level greater than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, abandoning the second sidelink resources, and restarting a same pre-emption process in a different empty sidelink resource.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level less than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and continuing to use the second sidelink resources after the same time period.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the second pre-emption signals on the first sidelink resources, detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain, detecting a part of the second pre-emption signals being overlapped with a part of the pre-emption signals, and detecting another part of the second pre-emption signals being not overlapped with another part of the pre-emption signals.

According to another embodiment in conjunction to the second aspect of the present disclosure, a number of the pre-emption processes is equal to a number of booking the second sidelink resources.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes transmitting the data TBs by an initial transmission and at least one re-transmission.

According to another embodiment in conjunction to the second aspect of the present disclosure, the method further includes transmitting the data TBs and reserving the same frequency resources repeatedly.

In the embodiment of the present disclosure, the user equipment and the method of wireless communication of same provide a resource pre-emption and reservation mechanism for sidelink data transport blocks (TBs) transmissions in 5th generation new radio (5G-NR) system to reduce or even prevent transmitting (Tx) collisions from multiple transmitting UEs. Furthermore, in the embodiment, two contention resolution techniques are also given to resolve two UEs trying to pre-empt same sidelink resource for transmission. The user equipment and the method of wireless communication of same in the embodiment also provide fast and reliable data transmission for NR-sidelink communication through resource pre-emption and reservation and/or contention resolution.

BRIEF DESCRIPTION OF DRAWINGS

In order to more clearly illustrate the embodiments of the present disclosure or related art, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures according to these figures without paying the premise.

FIG. 1 is a block diagram of a user equipment for wireless communication with another user equipment according to an embodiment of the present disclosure.

FIG. 2 is a diagram of a structure of a sidelink resource according to an embodiment of the present disclosure.

FIG. 3 is a diagram of a structure of a sidelink resource pool according to an embodiment of the present disclosure.

FIG. 4 is a scenario of pre-emption signals being transmitted by different user equipments in the same data region according to an embodiment of the present disclosure.

FIG. 5 is a scenario of pre-emption signals being transmitted by different user equipments in the same data region according to an embodiment of the present disclosure.

FIG. 6 is a scenario of pre-emption signals being transmitted by different user equipments in the same data region according to an embodiment of the present disclosure.

FIG. 7 is a scenario of vehicle-to-everything (V2X) communication according to an embodiment of the present disclosure.

FIG. 8 is a flowchart illustrating a method of wireless communication according to the present disclosure, from an aspect of operation of a user equipment for transmitting signals.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

FIG. 1 and FIG. 2 illustrate that, in some embodiments, a user equipment 100 for wireless communication includes a memory 102 and a processor 104 coupled to the memory 102. The processor 104 is configured to perform a wireless communication directly over a sidelink interface such as PC5 interface to at least one second user equipment 200, monitor and read at least one sidelink resource 311 used by the at least one second user equipment 200 such as a process 310, determine a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals 322, 323, 324, and 325 and a plurality of second

sidelink resources

332, 333, 334, and 335 available for transmitting a plurality of sidelink data transport blocks (TBs) , perform a plurality of pre-emption processes 320 by transmitting the pre-emption signals 322, 323, 324, and 325 for booking the

second sidelink resources

332, 333, 334, and 335, and transmit the sidelink data TBs using booked

second sidelink resources

332, 333, 334, and 335 and reserve a plurality of same frequency resources using the

second sidelink resources

332, 333, 334, and 335 in a current transmission for a subsequent transmission.

In some embodiments, the sidelink resources 311, the first sidelink resources, and the

second sidelink resources

332, 333, 334, and 335 are at least one of short transmission time interval (sTTI) sidelink resources and normal transmission time interval (nTTI) sidelink resources. The

second sidelink resources

332, 333, 334, and 335 are empty sidelink resources before performing the pre-emption processes 320, instead of being used by the at least one second user equipment 200.

In details, the user equipment 100 may be a user equipment for transmitting signals and the user equipment 200 may also be a user equipment for transmitting signals. In some embodiments, the communication between the user equipment 100 and the user equipment 200 over the sidelink interface such as the PC5 interface could be based on based on long term evolution (LTE) sidelink technology developed under 3rd generation partnership project (3GPP) and/or 5th generation new radio (5G-NR) radio access technology.

Furthermore, in some embodiments, resource selection as part of nTTI or sTTI transmission procedure from the user equipment 100 includes performing the process 310 of monitoring at least one sidelink resource 311 and reading nTTI messages or sTTI messages using the at least one sidelink resource 311, performing the process 320 of pre-emption of the

second sidelink resources

332, 333, 334, and 335 for nTTI transmissions or sTTI transmissions, and performing a process 330 of periodic data transmission (Tx) and reservation of next sidelink resources.

In details, the user equipment 100 has been authorized to use direct communication services like Proximity Services (ProSe) device-to-device (D2D) or vehicle-to-everything (V2X) is required to receive and monitor data packets being transmitted on the sidelink resource 311 from other user equipments such as the user equipment 200. Based on decoding sidelink control information using the at least one sidelink resource 311 of the user equipment 200, the user equipment 100 acquires knowledge about resource usage and reservation details of next transmissions.

Upon arrival of a data packet such as a process 321, the process 321 triggers the user equipment 100 to start plurality of pre-emption processes 320 by transmitting the pre-emption signals 322, 323, 324, and 325 for booking multiple sidelink nTTI or sTTI resources such as the

second sidelink resources

332, 333, 334, and 335 that are required for transmitting the data packet TB. A number of pre-emption processes 320 can be equal to a number of the

second sidelink resource

332, 333, 334, and 335 for sending nTTI or sTTI data TB’s initial transmission and all associated repetitions/re-transmissions.

For an example illustrated in the

processes

320 and 330, there are four pre-emption processes started by the user equipment 100 for booking four

second sidelink resources

332, 333, 334, and 335, such as four nTTI or sTTI resource units, to carry all of required initial and re-transmissions of the data TB during the Tx and reservation process 330. For periodic nTTI or sTTI data packet TBs with an arrival rate of once every X milli-seconds (ms) such as

processes

341 and 351, the user equipment 100 may reserve the same frequency resources in current TB transmissions 330 for subsequent TB transmissions 340 in a next X ms. The user equipment 100 may repeat the same reservation process 350 for the following X ms and so on.

In the embodiment of the present disclosure, the user equipment 100 provides a resource pre-emption and reservation mechanism for sidelink data transport blocks (TBs) transmissions in 5th generation new radio (5G-NR) system to reduce or even prevent transmitting (Tx) collisions from multiple transmitting UEs.

FIG. 3 illustrates that, in some embodiments, details of a sidelink resource pool 400 for nTTI or sTTI transmission is illustrated along with illustration of resource bookings during the pre-emption phase and resource reservation during data Tx phase. The sidelink resource pool 400 such as a nTTI or sTTI resource pool is divided into multiple resource units 401 for nTTI or sTTI transmissions and each nTTI or sTTI resource unit includes a guard period (GP) /automatic gain control (AGC) region 402 which may be one symbol length, a control region 403 for transmitting a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) , and a data region 404 which can be used for at least one of transmitting the pre-emption signals 406 and transmitting a physical sidelink shared channel (PSSCH) for transmitting the sidelink data TBs. The data region 404 can be of at least 3 symbols in length.

During the pre-emption phase, a pre-emption process involves determining a nTTI or sTTI resource unit is not being used by the user equipment 200 and transmitting a-pair of pre-emption signals to indicate the user equipment 200 intention of using a frequency resource unit after a certain time offset. In details, determining available nTTI or sTTI resources within data packet arrival interval is performed by the processor 104. Based on past monitoring and reading of nTTI or sTTI control and scheduling information in the process 310, the user equipment 100 makes an initial identification of all nTTI or sTTI resource units 405 that has been already reserved for transmission in the current data packet arrival interval X ms in the

processes

320 and 330.

Among other nTTI or sTTI resource units, the processor 104 of the user equipment 100 performs sensing of GP/AGC symbol of the GP/AGC region 402 and/or reading of PSCCH of the control region 403 to further determine a true availability of the first sidelink resource for transmitting the pre-emption signals 406. If an empty/unused nTTI or sTTI resource unit is found, the user equipment 100 may select the found resource unit and use the found resource unit for sending a pair of the pre-emption signals 406 in the data region 404 of the first sidelink resource.

Resource booking of pre-emption process is performed by the processor 104. Random selection with equal probability of two symbols out of total number of symbols in the data region 404 for sending the pair of pre-emption signals 406. Out of the pair of pre-emption signals 406 in the pre-emption process, each signal of the pre-emption signals 406 may be 1 symbol in length and holds identical information as carried by another signal of the pre-emption signals 406.

The processor 104 is further configured to transmit an information content in the pre-emption processes. The information content may at least include a time offset parameter indicating a time gap 407, which could be in terms of number of nTTI or sTTI resource units or number of milliseconds, to an intended nTTI or sTTI resource unit 408 for booking, a ProSe per packet priority (PPPP) level, a user equipment source identity (ID) , and/or a destination ID. The user equipment 100 repeats the same processes until all pre-emption processes are completed.

In detail, nTTI or sTTI data TB transmission and reservation of next resources are performed by the processor 104. The user equipment 100 uses the booked resource units 408 such as the

second sidelink resources

332, 333, 334, 335 in FIG. 2 for transmitting the nTTI or sTTI data packet TB arrived from an upper layer such as a medium access control (MAC) layer and at the same time reserves the same frequency resources X ms later in a process 409 for transmitting next data packet TB from the upper layer. Reservation of the process 409 is performed by indicating the time offset to a next reserved frequency resource in the SCI transmitted in the PSCCH.

FIG. 4 to FIG. 6 illustrate that, in some embodiments, different scenarios of pair of pre-emption signals are transmitted by different UEs such as the first user equipment 100 and the second user equipment 200 in the same data region of a nTTI or sTTI resource unit. In detail, FIG. 4 illustrates that, in some embodiments, the first user equipment 100 transmits pre-emption signal pair in

symbol

512 and 514, and the second user equipment 200 transmits pre-emption signal pair in

symbol

511 and 513. Since pre-emption signal pairs of the first user equipment 100 and the second user equipment 200 are not overlapped in the data region of the first sidelink resource, the first user equipment 100 and the second user equipment 200 would be able to listen to each other’s pre-emption indications. Furthermore, since indicated time gaps of the first user equipment 100 and the second user equipment 200 point to different nTTI or sTTI resource units in a time domain, there would be no conflict or collision in transmitting data packets. Therefore, pre-emption process is considered successful for both of the first user equipment 100 and the second user equipment 200.

FIG. 5 illustrates that, in some embodiments, the first user equipment 100 transmits pre-emption signal pair in

symbol

522 and 524, and the second user equipment 200 transmits pre-emption signal pair in

symbol

521 and 523. Both of the first user equipment 100 and the second user equipment 200 transmit pre-emption signal pairs in different data region symbols of the first sidelink resource and detect having both indicated the same time offset of Y ms. In this case, contention resolution would be necessary to avoid data packet transmission collision between the first user equipment 100 and the second user equipment 200. One of the following two contention resolution schemes could be used. In contention resolution scheme 1, both of the first user equipment 100 and the second user equipment 200 independently and randomly choose with equal probability whether or not continue to use the indicated frequency resource unit after Y ms, or abandon the indicated resource and restart the same pre-emption process in a different empty nTTI or sTTI resource.

In contention resolution scheme 2, when PPPP level of the current data packet is also included as part of pre-emption indication, the user equipment with lower PPPP level, the first user equipment 100 in this case, would abandon the indicated resource and restart the same pre-emption process in a different empty nTTI or sTTI resource. The user equipment with higher PPPP level, the second user equipment 200 in this case, would continue to use the indicated frequency resource unit after Y ms.

FIG. 6 illustrates that, in some embodiments, the first user equipment 100 transmits pre-emption signal pair in

symbol

532 and 533, and the second user equipment 200 transmits pre-emption signal pair in

symbol

531 and 532. In this case, both of the first user equipment 100 and the second user equipment 200 have an overlapping symbol in 532 in the data region of the first sidelink resource but still able to retrieve each other’s pre-emption signal in 531 for the first user equipment 100 and pre-emption signal in 533 for the second user equipment 200. Since indicated time offsets are not the same, there would be no conflict or collision in transmitting data packets. Therefore, resource pre-emption process is considered successful for both of the first user equipment 100 and the second user equipment 200.

In some embodiments, the

memories

102 and 202 each may include read-only memory (ROM) , random access memory (RAM) , flash memory, memory card, storage medium and/or other storage device. The

processors

104 and 204 each may include application-specific integrated circuit (ASIC) , other chipset, logic circuit and/or data processing device. The

processors

104 and 204 each may also include baseband circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules can be stored in

memories

102 and 202 and executed by

processors

104 and 204. The

memories

102 and 202 can be implemented within the

processors

104 and 204 or external to the

processors

104 and 204 in which case those can be communicatively coupled to the

processors

104 and 204 via various means as is known in the art.

FIG. 7 illustrates that, in some embodiments, the communication between the user equipment 100 and the user equipment 200 relates to vehicle-to-everything (V2X) communication including vehicle-to-vehicle (V2V) , vehicle-to-pedestrian (V2P) , and vehicle-to-infrastructure/network (V2I/N) according to LTE sidelink technology developed under 3rd generation partnership project (3GPP) and/or 5G-NR radio access technology. The

user equipments

100 and 200 are communicated with each other directly via a sidelink interface such as a PC5 interface.

FIG. 8 illustrate a method 600 of wireless communication according to the present disclosure, from an aspect of operation of the user equipment 100 for transmitting signals. The method 600 includes: at block 602, performing a wireless communication directly over a sidelink interface to at least one second user equipment 200, at block 604, monitoring and reading at least one sidelink resource used by the at least one second user equipment 200, at block 606, determining a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs) , at block 608, performing a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources, and at block 610, transmitting the sidelink data TBs using booked second sidelink resources and reserving a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.

In some embodiments, the method 600 further includes sensing the GP/AGC region of the first sidelink resource and/or reading the control region of the first sidelink resource to determine a true availability of the first sidelink resource for transmitting the pre-emption signals. The method 600 further includes transmitting the pre-emption signals in the data region of the first sidelink resource. The method 600 further includes performing a random selection with equal probability of two symbols out of a total number of symbols in the data region of the first sidelink resource for transmitting a pair of pre-emption signals. The method 600 further includes transmitting an information content in the pre-emption processes. The information content includes a time offset parameter indicating a time gap in terms of a number of sidelink resources or a number of milliseconds for booking the second sidelink resources, a ProSe per packet priority (PPPP) level, a user equipment source identity, and/or a destination identity.

In some embodiments, the method 600 includes reserving the same frequency resources by indicating a time offset in the SCI of the second sidelink resource. The method further includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment 200, and detecting the second pre-emption signals on the first sidelink resources being not overlapped with the pre-emption signals. The method 600 further includes detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain.

In some embodiments, the method 600 includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment 200, detecting the pre-emption signals and the second pre-emption signals in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and independently and randomly choosing with equal probability with the at least one second user equipment 200 whether or not continue to use the second sidelink resources after the same time period, or abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.

In some embodiments, the method 600 includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment 200, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level greater than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, abandoning the second sidelink resources, and restarting a same pre-emption process in a different empty sidelink resource.

In some embodiments, the method 600 includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment 200, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level less than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and continuing to use the second sidelink resources after the same time period.

In some embodiments, the method 600 includes monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment 200, detecting the second pre-emption signals on the first sidelink resources, detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain, detecting a part of the second pre-emption signals being overlapped with a part of the pre-emption signals, and detecting another part of the second pre-emption signals being not overlapped with another part of the pre-emption signals.

In some embodiments, the method 600 includes transmitting the data TBs by an initial transmission and at least one re-transmission. The method 600 further includes transmitting the data TBs and reserving the same frequency resources repeatedly.

A person having ordinary skill in the art understands that each of the units, algorithm, and steps described and disclosed in the embodiments of the present disclosure are realized using electronic hardware or combinations of software for computers and electronic hardware. Whether the functions run in hardware or software depends on the condition of application and design requirement for a technical plan. A person having ordinary skill in the art can use different ways to realize the function for each specific application while such realizations should not go beyond the scope of the present disclosure.

It is understood by a person having ordinary skill in the art that he/she can refer to the working processes of the system, device, and unit in the above-mentioned embodiment since the working processes of the above-mentioned system, device, and unit are basically the same. For easy description and simplicity, these working processes will not be detailed.

It is understood that the disclosed system, device, and method in the embodiments of the present disclosure can be realized with other ways. The above-mentioned embodiments are exemplary only. The division of the units is merely based on logical functions while other divisions exist in realization. It is possible that a plurality of units or components are combined or integrated in another system. It is also possible that some characteristics are omitted or skipped. On the other hand, the displayed or discussed mutual coupling, direct coupling, or communicative coupling operate through some ports, devices, or units whether indirectly or communicatively by ways of electrical, mechanical, or other kinds of forms.

The units as separating components for explanation are or are not physically separated. The units for display are or are not physical units, that is, located in one place or distributed on a plurality of network units. Some or all of the units are used according to the purposes of the embodiments.

Moreover, each of the functional units in each of the embodiments can be integrated in one processing unit, physically independent, or integrated in one processing unit with two or more than two units.

If the software function unit is realized and used and sold as a product, it can be stored in a readable storage medium in a computer. Based on this understanding, the technical plan proposed by the present disclosure can be essentially or partially realized as the form of a software product. Or, one part of the technical plan beneficial to the conventional technology can be realized as the form of a software product. The software product in the computer is stored in a storage medium, including a plurality of commands for a computational device (such as a personal computer, a server, or a network device) to run all or some of the steps disclosed by the embodiments of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM) , a random access memory (RAM) , a floppy disk, or other kinds of media capable of storing program codes.

While the present disclosure has been described in connection with what is considered the most practical and preferred embodiments, it is understood that the present disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

A user equipment for wireless communication, comprising:

a memory; and

a processor coupled to the memory and configured to:

perform a wireless communication directly over a sidelink interface to at least one second user equipment;

monitor and read at least one sidelink resource used by the at least one second user equipment;

determine a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs) ;

perform a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources; and

transmit the sidelink data TBs using booked second sidelink resources and reserve a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.
The user equipment of claim 1, wherein the sidelink resources, the first sidelink resources, and the second sidelink resources are at least one of short transmission time interval (sTTI) sidelink resources, and normal transmission time interval (nTTI) sidelink resources.
The user equipment of claim 1, wherein the second sidelink resources are empty sidelink resources before performing the pre-emption processes, instead of being used by the at least one second user equipment.
The user equipment of claim 2, wherein each of the sTTI sidelink resources and the nTTI sidelink resources comprises a guard period (GP) /automatic gain control (AGC) region, a control region for transmitting a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) , and a data region for at least one of transmitting the pre-emption signals and transmitting a physical sidelink shared channel (PSSCH) for transmitting the sidelink data TBs.
The user equipment of claim 4, wherein the GP/AGC region has one symbol length, and the data region has at least 3 symbols in length.
The user equipment of claim 4, wherein the processor is further configured to sense the GP/AGC region of the first sidelink resource and/or read the control region of the first sidelink resource to determine a true availability of the first sidelink resource for transmitting the pre-emption signals.
The user equipment of claim 6, wherein the processor is further configured to transmit the pre-emption signals in the data region of the first sidelink resource.
The user equipment of claim 5, wherein the processor is further configured to perform a random selection with equal probability of two symbols out of a total number of symbols in the data region of the first sidelink resource for transmitting a pair of pre-emption signals.
The user equipment of claim 8, wherein each pre-emption signal has one symbol length and holds identical information as carried by another pre-emption signal.
The user equipment of claim 8, wherein the processor is further configured to transmit an information content in the pre-emption processes, the information content comprises a time offset parameter indicating a time gap in terms of a number of sidelink resources or a number of milliseconds for booking the second sidelink resources, a ProSe per packet priority (PPPP) level, a user equipment source identity, and/or a destination identity.
The user equipment of claim 4, wherein the processor is further configured to reserve the same frequency resources by indicating a time offset in the SCI of the second sidelink resources.
The user equipment of claim 1, wherein the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, and the processor is further configured to detect the second pre-emption signals on the first sidelink resources being not overlapped with the pre-emption signals.
The user equipment of claim 12, wherein the processor is further configured to detect the second pre-emption signals having a time gap with the pre-emption signals in a time domain.
The user equipment of claim 1, wherein the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals and the second pre-emption signals in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to independently and randomly choose with equal probability with the at least one second user equipment whether or not continue to use the second sidelink resources after the same time period, or abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.
The user equipment of claim 1, wherein the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level greater than the first PPPP level in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.
The user equipment of claim 1, wherein the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level less than the first PPPP level in different data regions of the first sidelink resources, detect the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and the processor is further configured to continue to use the second sidelink resources after the same time period.
The user equipment of claim 1, wherein the processor is further configured to monitor and read a plurality of second pre-emption signals transmitted by the at least one second user equipment, detect the second pre-emption signals on the first sidelink resources, detect the second pre-emption signals having a time gap with the pre-emption signals in a time domain, detect a part of the second pre-emption signals being overlapped with a part of the pre-emption signals, and detect another part of the second pre-emption signals being not overlapped with another part of the pre-emption signals.
The user equipment of claim 1, wherein a number of the pre-emption processes is equal to a number of booking the second sidelink resources.
The user equipment of claim 1, wherein the processor is further configured to transmit the data TBs by an initial transmission and at least one re-transmission.
The user equipment of claim 1, wherein the processor is further configured to transmit the data TBs and reserve the same frequency resources repeatedly.
A method of wireless communication of a user equipment, comprising:

performing a wireless communication directly over a sidelink interface to at least one second user equipment;

monitoring and reading at least one sidelink resource used by the at least one second user equipment;

determining a plurality of first sidelink resources available for transmitting a plurality of pre-emption signals and a plurality of second sidelink resources available for transmitting a plurality of sidelink data transport blocks (TBs) ;

performing a plurality of pre-emption processes by transmitting the pre-emption signals for booking the second sidelink resources; and

transmitting the sidelink data TBs using booked second sidelink resources and reserving a plurality of same frequency resources using the second sidelink resources in a current transmission for a subsequent transmission.
The method of claim 21, wherein the sidelink resources, the first sidelink resources, and the second sidelink resources are at least one of short transmission time interval (sTTI) sidelink resources and normal transmission time interval (nTTI) sidelink resources.
The method of claim 21, wherein the second sidelink resources are empty sidelink resources before performing the pre-emption processes, instead of being used by the at least one second user equipment.
The method of claim 22, wherein each of the sTTI sidelink resources and the nTTI sidelink resources comprises a guard period (GP) /automatic gain control (AGC) region, a control region for transmitting a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) , and a data region for at least one of transmitting the pre-emption signals and transmitting a physical sidelink shared channel (PSSCH) for transmitting the sidelink data TBs.
The method of claim 24, wherein the GP/AGC region has one symbol length, and the data region has at least 3 symbols in length.
The method of claim 24, further comprising sensing the GP/AGC region of the second sidelink resource and/or reading the control region of the first sidelink resource to determine a true availability of the first sidelink resource for transmitting the pre-emption signals.
The method of claim 26, further comprising transmitting the pre-emption signals in the data region of the first sidelink resource.
The method of claim 25, further comprising performing a random selection with equal probability of two symbols out of a total number of symbols in the data region of the first sidelink resource for transmitting a pair of pre-emption signals.
The method of claim 28, wherein each pre-emption signal has one symbol length and holds identical information as carried by another pre-emption signal.
The method of claim 28, further comprising transmitting an information content in the pre-emption processes, wherein the information content comprises a time offset parameter indicating a time gap in terms of a number of sidelink resources or a number of milliseconds for booking the second sidelink resources, a ProSe per packet priority (PPPP) level, a user equipment source identity, and/or a destination identity.
The method of claim 24, further comprising reserving the same frequency resources by indicating a time offset in the SCI of the second sidelink resource.
The method of claim 21, further comprising monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, and detecting the second pre-emption signals on the first sidelink resources being not overlapped with the pre-emption signals.
The method of claim 32, further comprising detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain.
The method of claim 21, further comprising monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals and the second pre-emption signals in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and independently and randomly choosing with equal probability with the at least one second user equipment whether or not continue to use the second sidelink resources after the same time period, or abandon the second sidelink resources and restart a same pre-emption process in a different empty sidelink resource.
The method of claim 21, wherein further comprising monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level greater than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, abandoning the second sidelink resources, and restarting a same pre-emption process in a different empty sidelink resource.
The method of claim 21, further comprising monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the pre-emption signals with a first PPPP level and the second pre-emption signals with a second PPPP level less than the first PPPP level in different data regions of the first sidelink resources, detecting the pre-emption signals and the second pre-emption signals having a same time offset in a time period, and continuing to use the second sidelink resources after the same time period.
The method of claim 21, further comprising monitoring and reading a plurality of second pre-emption signals transmitted by the at least one second user equipment, detecting the second pre-emption signals on the first sidelink resources, detecting the second pre-emption signals having a time gap with the pre-emption signals in a time domain, detecting a part of the second pre-emption signals being overlapped with a part of the pre-emption signals, and detecting another part of the second pre-emption signals being not overlapped with another part of the pre-emption signals.
The method of claim 21, wherein a number of the pre-emption processes is equal to a number of booking the second sidelink resources.
The method of claim 21, further comprising transmitting the data TBs by an initial transmission and at least one re-transmission.
The method of claim 21, further comprising transmitting the data TBs and reserving the same frequency resources repeatedly.