Detailed Description
So that the manner in which the features and techniques of the embodiments of the present application can be understood in more detail, a more particular description of the application, briefly summarized below, may be had by reference to the appended drawings, which are not intended to be limiting of the embodiments of the present application.
Before describing embodiments of the present application in detail, related art will be briefly described.
A non-terrestrial communication network (Non Terrestrial Network, NTN) provides communication services to terrestrial users using satellite communications. Satellite communications have many unique advantages over terrestrial cellular communications. First, satellite communications are not limited by the user territory, for example, general land communications cannot cover areas where communication devices cannot be installed, such as oceans, mountains, or deserts, or communication coverage is not available due to rarity of population, while for satellite communications, each corner of the earth can be theoretically covered by satellite communications because one satellite can cover a larger area of the ground and the satellite can orbit around the earth. And secondly, satellite communication has higher social value. Satellite communication can be covered in remote mountain areas, poor and backward countries or regions with lower cost, so that people in the regions enjoy advanced voice communication and mobile internet technology, and the digital gap between developed regions is reduced, and the development of the regions is promoted. Again, the satellite communication distance is far, and increasing the communication distance does not significantly increase the cost of communication; and finally, the satellite communication has high stability and is not limited by natural disasters.
Communication satellites are classified into Low Earth Orbit (LEO) satellites, medium Earth Orbit (MEO) satellites, geosynchronous Orbit (Geostationary Earth Orbit, GEO) satellites, and high elliptical Orbit (HIGH ELLIPTICAL Orbit, HEO) satellites, etc. according to the Orbit heights. The LEO and GEO are briefly described below, respectively.
The LEO has a track height in the range of 500km to 1500km, with a corresponding track period of about 1.5 hours to 2 hours. The signal propagation delay for single hop communications between terminal devices is typically less than 20ms. The maximum satellite visibility time is 20 minutes. The signal propagation distance is short, the link loss is less, and the requirement on the transmitting power of the terminal equipment is not high.
The orbit height of GEO is 35786km and the period of rotation around the earth is 24 hours. The signal propagation delay for single hop communications between terminal devices is typically 250ms. In order to ensure the coverage of the satellite and improve the system capacity of the whole satellite communication system, the satellite adopts multiple beams to cover the ground, one satellite can form tens or even hundreds of beams to cover the ground, and one satellite beam can cover a ground area with a diameter of tens to hundreds of kilometers.
In order to ensure the coverage of the satellite and improve the system capacity of the whole satellite communication system, the satellite adopts multiple beams to cover the ground, one satellite can form tens or even hundreds of beams to cover the ground, and one satellite beam can cover a ground area with a diameter of tens to hundreds of kilometers.
A brief description of the hybrid automatic repeat request (Hybrid Automatic Repeat reQuest, HARQ) mechanism in a New Radio (NR) system follows.
The NR system includes a two-stage retransmission mechanism, a HARQ mechanism of a medium access Control (MEDIA ACCESS Control, MAC) layer and an automatic retransmission request (Automatic Repeat reQuest, ARQ) mechanism of a (Radio Link Control, RLC) layer. The retransmission of lost or erroneous data is mainly handled by the HARQ mechanism of the MAC layer and complemented by the retransmission function of the RLC layer. The HARQ mechanism of the MAC layer can provide fast retransmission and the ARQ mechanism of the RLC layer can provide reliable data transmission.
HARQ uses Stop-and-Wait Protocol (Stop-and-Wait Protocol) to transmit data. In the stop-and-wait protocol, after a transmitting end transmits a Transport Block (TB), data transmission is stopped to wait for acknowledgement. Thus, the sender stops data transmission after each transmission to wait for acknowledgement, which results in low user throughput. Thus, the NR system uses a plurality of parallel HARQ processes, and when one HARQ process waits for acknowledgement information, the transmitting end can continue to transmit data using another HARQ process. These HARQ processes together constitute one HARQ entity that incorporates a de-equalization protocol, allowing continuous transmission of data. HARQ includes uplink HARQ and downlink HARQ. Uplink HARQ is for uplink data transmission, and downlink HARQ is for downlink data transmission. The uplink HARQ and the downlink HARQ are mutually independent.
Based on the current NR protocol, each serving cell corresponding to a terminal device has a respective HARQ entity. Each HARQ entity maintains a set of parallel downlink HARQ processes and a set of parallel uplink HARQ processes. A maximum of 16 HARQ processes may be supported per uplink and downlink carrier. The network device may indicate the maximum number of HARQ processes to the middle terminal device through a radio resource control (Radio Resource Control, RRC) signaling semi-static configuration according to the network deployment scenario. If the network device does not provide the corresponding configuration parameters, the downlink default HARQ process number is 8, and the maximum HARQ process number supported by each uplink carrier is always 16. Each HARQ process corresponds to a HARQ process Identification (ID). For the downlink, the broadcast control channel (Broadcast Control Channel, BCCH) uses a dedicated broadcast HARQ process. For uplink, message 3 (Msg 3) transmission in the random process uses HARQ ID 0.
For terminal equipment which does not support downlink space division multiplexing, each downlink HARQ process can only process 1 TB at the same time, and for terminal equipment which does support downlink space division multiplexing, each downlink HARQ process can process 1 or 2 TB at the same time. Each uplink HARQ process of the terminal simultaneously processes 1 TB.
HARQ is classified into synchronous and asynchronous types in the time domain and into non-adaptive and adaptive types in the frequency domain. An asynchronous adaptive HARQ mechanism is used for both uplink and downlink of the NR system. Asynchronous HARQ, i.e. retransmission, may occur at any time, the time interval between the retransmission of the same TB and the last transmission being not fixed. The adaptive HARQ may change the frequency domain resources and modulation and coding strategy (Modulation and Coding Scheme, MCS) used for the retransmission.
Logical channel priorities (Logical Channel Prioritization, LCP) in the NR system are briefly described below.
As in the long term evolution (long term evolution, LTE) system, in the NR system, the network device allocates uplink transmission resources based on each terminal device, rather than allocating uplink transmission resources based on each radio bearer, and it is determined by the terminal device which radio bearer data can be transmitted in the allocated uplink transmission resources.
Based on the uplink transmission resources configured by the network device, the terminal device needs to determine the transmission data amount of each logical channel in the primary MAC protocol data unit (Protocol Data Unit, PDU), and in some cases, the terminal device allocates resources for a MAC Control Element (CE). To achieve multiplexing of the uplink logical channels, each uplink logical channel needs to be assigned a priority. For a MAC PDU with a given size, under the condition that a plurality of uplink logic channels simultaneously have data transmission requirements, the resources of the MAC PDU are sequentially allocated according to the order from the large to the small of the logic channel priorities corresponding to the uplink logic channels. Meanwhile, in order to give consideration to fairness among different logic channels, a concept of priority bit rate (Prioritized Bit Rate, PBR) is introduced, and when the terminal equipment performs logic channel multiplexing, the minimum data rate requirement of each logic channel needs to be ensured first, so that the situation that other low-priority uplink logic channels of the terminal equipment are starved for uplink resources because the uplink logic channels with high priority always occupy the uplink resources allocated to the terminal equipment by the network equipment is avoided.
A brief description of Configuration Grant (CG) follows.
In order to better serve periodic traffic, the concept of pre-configured resources is introduced, downstream called Semi-persistent scheduling (Semi-PERSISTENT SCHEDULING, SPS) and upstream called CG.
The NR system supports the transmission of two types of uplink configuration grants:
1. Physical Uplink SHARED CHANNEL, PUSCH) transmission based on a first type of configuration grant (configured GRANT TYPE 1).
All transmission resources and transmission parameters including time domain resources, frequency domain resources, period of time domain resources, MCS, repetition number, frequency hopping, and HARQ process number are configured by the network device through RRC signaling. After receiving the RRC configuration parameter, the terminal device may immediately use the configured transmission parameter to perform PUSCH transmission on the configured time-frequency resource.
2. PUSCH transmission based on a second class of configuration grants (configured GRANT TYPE 2).
Firstly, configuring transmission resources and transmission parameters including period, repetition times, frequency hopping, HARQ process number and the like of time domain resources by isomorphic RRC signaling of network equipment. Then, a physical downlink control channel (Physical Downlink Control Channel, PDCCH) scrambled by using the configuration scheduling radio network temporary identity (Configured Scheduling Radio Network Temporary Identifier, CS-RNTI) activates PUSCH transmission granted based on the second type of configuration, and simultaneously configures other transmission resources and transmission parameters including time domain resources, frequency domain resources, and MCS, etc. When receiving the RRC configuration parameters, the terminal equipment cannot immediately use the resources and parameters configured by the configuration parameters to carry out the PUSCH transmission, but must receive the corresponding PDCCH activation and configure other resources and parameters to carry out the PUSCH transmission.
Because the maximum number of HARQ processes supported by the terminal device is 16, for each CG configuration, the network device configures the terminal device with a limited number of HARQ process numbers, and the terminal device uses these HARQ process numbers to perform uplink transmission on CG resources in a polling manner. Assuming that the HARQ process number of CG resource at time t0 and the HARQ process of CG resource at time t1 are both HARQ ID i, after the terminal device at time t0 packs MAC PDU1, MAC PDU1 is stored in HARQ ID i until time t1, and since the HARQ process is the same as that used at time t0, MAC PDU1 will be discarded (flush) even if MAC PDU1 has not been correctly transmitted at this time. Thus, a configuration grant timer (configured GRANT TIMER) is introduced for each HARQ process. The maintenance mode of Configured GRANT TIMER is:
If the terminal device performs uplink transmission on the resource scheduled by the PDCCH, and the HARQ process used by the uplink transmission can be used for configuring authorized transmission, the peripheral terminal device starts or restarts configured GRANT TIMER corresponding to the HARQ process. If the terminal device performs uplink transmission on the configured grant resource, the terminal device starts or restarts configured GRANT TIMER corresponding to the HARQ process. If the terminal device receives PDCCH indication configured GRANT TYPE 2 active, the terminal device stops configured GRANT TIMER that is running. Before configured GRANT TIMER corresponding to a certain HARQ process times out, the MAC PDU stored in the HARQ process cannot be flushed.
In an NR system, after a terminal device utilizes CG resources to send MAC PDU, a CG timer is started to start monitoring CS-RNTI and PDCCH scrambled by C-RNTI. The transmitted MAC PDU is stored in a HARQ buffer (buffer). If the terminal device receives the C-RNTI scrambled PDCCH to schedule uplink transmission, the terminal device considers that the NDI is overturned no matter what value is taken by a new data indication (New Data Indication, NDI) in the PDCCH, and the terminal device obtains the MAC PDU to be transmitted from a multiplexing and assembling entity (Multiplexing and assembly entity). And, once the transmission is completed on the dynamically scheduled resource, the new MAC PDU will be saved in the HARQ buffer, and the MAC PDU transmitted by the previous CG will be flushed. This can result in the loss of CG transmitted data.
Because the CG resources are preconfigured, the network device does not know when the terminal device will make an uplink transmission on the CG resources unless the network device detects an uplink transmission on the CG resources. In the ground network of the NR system, propagation delay between the terminal device and the network device is small, and the network device may alleviate the above-described problem of data loss to some extent by implementing the method. For example, the network device dynamically schedules uplink transmissions this year after uplink transmission detection for each CG resource.
Compared with the cellular network adopted by the traditional NR system, the propagation delay between the terminal equipment and the satellite in the NTN is larger, especially in a GEO scene, and the propagation delay is about tens of milliseconds. If uplink can be dynamically scheduled after uplink detection of CG resources is waited for each time, larger scheduling delay is probably caused. The probability of NTN scene data loss is high.
The inventors have found that different services have different quality of service (Quality of Service, qoS) properties when carrying out data transmission, such as delay sensitive services or services sensitive to transmission reliability. For reliability sensitive data, if the HARQ buffer of CG transmission is emptied every time the dynamically scheduled resource, the reliability of the data transmission will be reduced.
The technical scheme of the embodiment of the application can be applied to various communication systems, such as a global system for mobile communications (global system of mobile communication, GSM) system, a code division multiple access (code division multiple access, CDMA) system, a wideband code division multiple access (wideband code division multiple access, WCDMA) system, a general packet radio service (GENERAL PACKET radio service, GPRS), an LTE system, an LTE frequency division duplex (frequency division duplex, FDD) system, an LTE time division duplex (time division duplex, TDD) system, a long term evolution (advanced long term evolution, LTE-A) system, a New Radio (NR) system, an evolution system of the NR system, an LTE-based access to unlicensed spectrum (LTE-U) system on an unlicensed frequency band, an NR-based access to unlicensed spectrum, NR-U) system on an unlicensed frequency band, a universal mobile communication system (universal mobile telecommunication system, UMTS), a global interconnection microwave access (worldwide interoperability for microwave access, wiMAX) communication system, a wireless local area network (wireless local area networks, WLAN), a wireless fidelity (WIRELESS FIDELITY, wiFi), a next-generation communication system or other communication systems.
The system architecture and the service scenario described in the embodiments of the present application are for more clearly describing the technical solution provided in the embodiments of the present application, and do not constitute a limitation on the technical solution provided in the embodiments of the present application, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiments of the present application is equally applicable to similar technical problems.
The network device involved in the embodiment of the present application may be a common base station (such as NodeB or eNB or gNB), a new radio controller (new radio controller, NR controller), a centralized network element (centralized unit), a new radio base station, a remote radio module, a micro base station, a relay (relay), a distributed network element (distributed unit), a receiving point (transmission reception point, TRP), a transmission point (transmission point, TP), or any other device. The embodiment of the application does not limit the specific technology and the specific equipment form adopted by the network equipment. For convenience of description, in all embodiments of the present application, the above-mentioned apparatus for providing a wireless communication function for a terminal device is collectively referred to as a network device.
In the embodiment of the application, the terminal device may be any terminal, for example, the terminal device may be a user device for machine type communication. That is, the terminal device may also be referred to as a user equipment UE, a Mobile Station (MS), a mobile terminal (mobile terminal), a terminal (terminal), etc., which may communicate with one or more core networks via a radio access network (radio access network, RAN), e.g., the terminal device may be a mobile phone (or "cellular" phone), a computer with a mobile terminal, etc., e.g., the terminal device may also be a portable, pocket, hand-held, computer-built-in or car-mounted mobile device that exchanges voice and/or data with the radio access network. The embodiment of the application is not particularly limited.
Alternatively, the network devices and terminal devices may be deployed on land, including indoor or outdoor, hand-held or vehicle-mounted, on water, on air planes, balloons, and satellites. The embodiment of the application does not limit the application scenes of the network equipment and the terminal equipment.
Optionally, communication between the network device and the terminal device and between the terminal device and the terminal device may be performed through a licensed spectrum (licensed spectrum), communication may be performed through an unlicensed spectrum (unlicensed spectrum), or communication may be performed through both the licensed spectrum and the unlicensed spectrum. Communication between the network device and the terminal device and between the terminal device and the terminal device may be performed through a frequency spectrum of 7 gigahertz (GHz) or less, may be performed through a frequency spectrum of 7GHz or more, and may be performed using a frequency spectrum of 7GHz or less and a frequency spectrum of 7GHz or more simultaneously. The embodiment of the application does not limit the frequency spectrum resources used between the network equipment and the terminal equipment.
Generally, the number of connections supported by the conventional communication system is limited and easy to implement, however, as the communication technology advances, the mobile communication system will support not only conventional communication but also, for example, device-to-device (D2D) communication, machine-to-machine (machine to machine, M2M) communication, machine type communication (MACHINE TYPE communication, MTC), inter-vehicle (vehicle to vehicle, V2V) communication, and the like, and the embodiments of the present application can also be applied to these communication systems.
Exemplary, a communication system 100 to which embodiments of the present application may be applied is shown in fig. 1. The communication system 100 may include a network device 110, and the network device 110 may be a device that communicates with a terminal device 120 (or referred to as a communication terminal, terminal). Network device 110 may provide communication coverage for a particular geographic area and may communicate with terminal devices located within the coverage area. Alternatively, the network device 110 may be a base station (Base Transceiver Station, BTS) in a GSM system or a CDMA system, a base station (NodeB, NB) in a WCDMA system, an evolved base station (Evolutional Node B, eNB or eNodeB) in an LTE system, or a radio controller in a cloud radio access network (Cloud Radio Access Network, CRAN), or the network device may be a mobile switching center, a relay station, an access point, a vehicle device, a wearable device, a hub, a switch, a bridge, a router, a network-side device in a 5G network, or a network device in a future evolved public land mobile network (Public Land Mobile Network, PLMN), etc.
The communication system 100 further comprises at least one terminal device 120 located within the coverage area of the network device 110. "terminal device" as used herein includes, but is not limited to, a device configured to receive/transmit communication signals via a wireline connection, such as via a public-switched telephone network (Public Switched Telephone Networks, PSTN), a digital subscriber line (Digital Subscriber Line, DSL), a digital cable, a direct cable connection, and/or another data connection/network, and/or via a wireless interface, such as for a cellular network, a wireless local area network (Wireless Local Area Network, WLAN), a digital television network, such as a DVB-H network, a satellite network, an AM-FM broadcast transmitter, and/or another terminal device, and/or an internet of things (Internet of Things, ioT) device. Terminal devices arranged to communicate over a wireless interface may be referred to as "wireless communication terminals", "wireless terminals" or "mobile terminals". Examples of mobile terminals include, but are not limited to, satellite or cellular telephones, personal communication systems (Personal Communications System, PCS) terminals that may combine a cellular radiotelephone with data processing, facsimile, and data communication capabilities, PDAs that may include a radiotelephone, pager, internet/intranet access, web browser, organizer, calendar, and/or a global positioning system (Global Positioning System, GPS) receiver, and conventional laptop and/or palmtop receivers or other electronic devices that include a radiotelephone transceiver. A terminal device may refer to an access terminal, user Equipment (UE), subscriber unit, subscriber station, mobile station, remote terminal, mobile device, user terminal, wireless communication device, user agent, or User Equipment. An access terminal may be a cellular telephone, a cordless telephone, a session initiation protocol (Session Initiation Protocol, SIP) phone, a wireless local loop (Wireless Local Loop, WLL) station, a Personal digital assistant (Personal DIGITAL ASSISTANT, PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in a 5G network or a terminal device in a future evolved PLMN, etc.
Alternatively, direct terminal (D2D) communication may be performed between the terminal devices 120.
Alternatively, the 5G system or 5G network may also be referred to as a New Radio (NR) system or NR network.
Fig. 1 illustrates one network device and two terminal devices by way of example, and the communication system 100 may alternatively include multiple network devices and may include other numbers of terminal devices within the coverage area of each network device, as embodiments of the application are not limited in this regard.
Optionally, the communication system 100 may further include a network controller, a mobility management entity, and other network entities, which are not limited by the embodiment of the present application.
It should be understood that a device having a communication function in a network/system according to an embodiment of the present application may be referred to as a communication device. Taking the communication system 100 shown in fig. 1 as an example, the communication device may include a network device 110 and a terminal device 120 with communication functions, where the network device 110 and the terminal device 120 may be specific devices described above, which are not described herein, and the communication device may further include other devices in the communication system 100, such as a network controller, a mobility management entity, and other network entities, which are not limited in the embodiment of the present application.
An optional processing flow of the data packet reassembly method provided by the embodiment of the application, as shown in fig. 2, includes the following steps:
Step S201, under the condition that the terminal equipment transmits data on the configuration authorized resource and the configuration authorized timer runs, the terminal equipment receives scheduling information and first indication information aiming at uplink new transmission, wherein the first indication information is used for determining whether data packet reorganization is carried out on the transmission of the dynamic authorized resource.
In some embodiments, the first indication information may be sent by the network device to the terminal device, and the first indication information may be carried in an RRC message.
In some embodiments, the scheduling information for uplink new transmission includes scheduling the scheduling information for uplink new transmission using a C-RNTI scrambled PDCCH.
In some embodiments, the hybrid automatic repeat request process associated with the uplink new transmission is the same as the hybrid automatic repeat request process associated with transmitting data on the configured grant resources.
In some embodiments, in a case where the first indication information is used to determine that packet reassembly is performed, the method may further include:
in step S202, the terminal device reassembles the data packet by multiplexing and assembling the entity.
In some embodiments, the method may further comprise:
in step S203, the terminal device transmits the reassembled data packet by using the dynamic grant resources in the scheduling information.
For step S201, the first indication information may indicate whether to perform packet reassembly for the transmission of the dynamic grant resources based on different dimensions. If the first indication information indicates whether to carry out data packet reorganization for the transmission of the dynamic authorized resource based on the CG, namely, if the data packet reorganization is carried out for the data transmitted on the CG resource when the data is transmitted by utilizing the dynamic authorized resource for the data transmitted on the CG resource. If the first indication information indicates whether to carry out data packet reorganization for the transmission of the dynamic grant resources based on the logic channels, namely, whether to carry out data packet reorganization for the data corresponding to the logic channels when the data corresponding to one or more logic channels are transmitted by using CG resources and then the data corresponding to the dynamic grant resources are transmitted. If the first indication information indicates whether to carry out data packet reorganization for the transmission of the dynamic authorization resource based on the MAC CEs, namely, if one or more MAC CEs carry out data packet reorganization for the MAC CEs when the data is transmitted by utilizing the dynamic authorization resource after the CG resource is transmitted.
The following describes the packet reassembly method according to the embodiment of the present application based on the above three different dimensions, respectively.
And under the condition that the terminal equipment transmits data on the configuration authorized resource and the configuration authorized timer runs, the terminal equipment receives the PDCCH scrambled by the C-RNTI sent by the network equipment to schedule uplink new transmission.
In some scenarios, for each CG configuration, the network device sends first indication information to the terminal device, where the first indication information is used to determine whether the terminal device performs packet reassembly when transmitting data using the PDCCH scheduled dynamic grant resources.
In a specific implementation, the network device may send first indication information to the terminal device through an RRC message, for example, the network device configures configuration authorization configuration (configured Grant Config) through an RRC reconfiguration message, where the configured Grant Config includes, in addition to parameters including a nrofHARQ-process parameter indicating the number of HARQ Processes available for the uplink resource, a periodicity parameter indicating a time interval between uplink grants, a CS-RNTI, and a CG timer, the first indication information is indication information indicating whether to reassemble a data packet (rebuild MAC PDU). In a network implementation, a logical channel transmission requiring high transmission reliability may be configured on the CG configuration, i.e. allowedCGlist is directed to the configured Grant config in LogicalChannelConfig of the logical channels whose transmission reliability satisfies the first condition.
In the implementation, the network device may also send the first indication information through the PDCCH for scheduling the terminal device to transmit data using the dynamic grant resource, that is, the first indication information is carried in the PDCCH.
If the configuration rebuild MAC PDU in the first indication information is in an on state, it can be determined that after the terminal device transmits data on the configuration authorized resource, if the terminal device receives scheduling information for uplink new transmission, the terminal device needs to reorganize a data packet before transmitting the data by using the dynamic authorized resource, where the data transmitted by the dynamic authorized resource and the data transmitted by the configuration authorized resource are for the same HARQ process.
When the data packet is reorganized, the terminal device can acquire data except padding information (padding) in the MAC PDU stored in the HARQ buffer, wherein the data can be data corresponding to each logic channel and/or MAC CE transmitted on the CG resource. And generating the MAC PDU for uplink transmission by the acquired data and the data existing in the multiplexing and assembling entity. The new MAC PDU utilizes PDCCH scheduled dynamic grant resource transmission.
In a scenario that the first indication information is specific to configuration grant, as shown in fig. 3, a terminal device uses configuration grant resources to transmit logical channel 1 (LCH 1) and logical channel 3 (LCH 3), MAC PDUs transmitted by using the configuration grant resources are stored in HARQ buffers, during operation of a configuration grant timer, if the terminal device receives scheduling information and the first indication information sent by a network device and scrambled PDCCH by using C-RNTI, and the first indication information indicates packet reassembly, the terminal device sends data except padding in the MAC PDUs stored in the HARQ buffers to a multiplexing and assembling entity, the multiplexing and assembling entity stores data corresponding to logical channel 4 (LCH 4) and logical channel 5 (LCH 5), and the terminal device generates the acquired data and the data stored in the multiplexing and assembling entity into the MAC PDUs for uplink transmission based on a logical channel priority process. In the embodiment of the application, the priority of the data corresponding to LCH5 stored in the multiplexing and assembling entity is lowest, and the dynamic authorization resource is insufficient to accommodate the data except for padding in LCH1 and LCH3, the data corresponding to LCH4 and the data corresponding to LCH5, so that when the terminal equipment recombines the data packet, only the data except for padding in LCH1 and LCH3 and the data corresponding to LCH4 are recombined, and the data corresponding to LCH5 is continuously stored in the multiplexing and assembling entity. In other embodiments, if the dynamic grant resources are sufficient to accommodate the data except padding in LCH1 and LCH3, the data corresponding to LCH4, and the data corresponding to LCH5, when the terminal device reassembles the data packet, the data except padding in LCH1 and LCH3, the data corresponding to LCH4, and the data corresponding to LCH5 are reassembled.
In this scenario, the network device instructs CG configuration to reassemble the data packets, so that the problem of data loss that may be caused when dynamic authorization is used to override configuration authorization can be avoided. According to the data packet reorganizing method provided by the embodiment of the application, the terminal equipment can reorganize the data corresponding to the service or the logic channel with high priority stored in the HARQ buffer based on the logic channel priority process, so that the data newly transmitted by the terminal equipment by utilizing the dynamic grant resources comprises the data corresponding to the service or the logic channel with high priority transmitted by the terminal equipment by utilizing the configuration grant resources, the data loss is avoided, and the data transmission efficiency is improved.
In other scenarios, for each logical channel, the network device sends first indication information to the terminal device, where the first indication information is used to determine whether the terminal device performs packet reassembly on data corresponding to the logical channel when transmitting data using the dynamic grant resources scheduled by the PDCCH.
In a specific implementation, the network device may send first indication information to the terminal device through an RRC message, for example, the network device configures the logical channel configuration through an RRC reconfiguration message (Logical Channel Config), where Logical Channel Config includes the first indication information in addition to parameters such as allowedCG-List that indicate where the logical channel allows transmission on configuredGrantConfig, where the first indication information is indication information indicating whether to reassemble the data packet (rebuild MAC PDU).
If the configuration rebuild MAC PDU in the first indication information is in an on state, it can be determined that after the terminal device transmits data on the configuration authorized resource, if the terminal device receives scheduling information of a PDCCH scheduling uplink newly transmitted by using a C-RNTI scrambling, the terminal device obtains information of a logical channel transmitted on the configuration authorized resource, where the information of the logical channel may be all logical channels transmitted on the configuration authorized resource and the first indication information corresponding to each logical channel, and the terminal device determines the first logical channel in all logical channels.
The number of the first logic channels can be one or a plurality of the first logic channels, first indication information corresponding to the first logic channels indicates that data corresponding to the first logic channels are subjected to data packet reorganization when the first logic channels are transmitted on the dynamic grant resources after the first logic channels are transmitted on the dynamic grant resources, the data transmitted by the dynamic grant resources at this time comprises the data corresponding to the first logic channels, and the data transmitted by the dynamic grant resources are aimed at the same HARQ process.
When the data packet is reorganized, the terminal device can acquire the data corresponding to the first logic channel stored in the HARQ buffer. And generating the MAC PDU for uplink transmission by the acquired data and the data existing in the multiplexing and assembling entity. The new MAC PDU utilizes PDCCH scheduled dynamic grant resource transmission. The data stored in the HARQ buffer except the data corresponding to the first logical channel may be discarded.
In a scenario that the first indication information is specific to a logical channel, as shown in fig. 4, another detailed processing flow of data transmission provided in the embodiment of the present application, a terminal device transmits logical channel 1 (LCH 1) and logical channel 3 (LCH 3) by using a configuration grant resource, the first indication information corresponding to LCH1 indicates packet reassembly, the first indication information corresponding to LCH3 indicates that the packet is not reassembled, and a MAC PDU transmitted by using the configuration grant resource is stored in an HARQ buffer. During the running period of the configuration authorization timer, if the terminal equipment receives the scheduling information of the uplink new transmission of the PDCCH which is scrambled by the C-RNTI and sent by the network equipment, the terminal equipment sends the data corresponding to the LCH1 stored in the HARQ buffer to a multiplexing and assembling entity, the multiplexing and assembling entity stores the data corresponding to the logical channel 4 (LCH 4) and the logical channel 5 (LCH 5), and the terminal equipment generates the MAC PDU for uplink transmission from the acquired data corresponding to the LCH1 and the data stored in the multiplexing and assembling entity based on the logical channel priority process. In the embodiment of the application, if the dynamic authorized resource is enough to accommodate the data corresponding to LCH1, the data corresponding to LCH4 and the data corresponding to LCH5, the terminal equipment performs data packet reorganization on the data corresponding to LCH1, the data corresponding to LCH4 and the data corresponding to LCH5 when reorganizing the data packets. In other embodiments, the priority of the data corresponding to LCH5 stored in the multiplexing and assembling entity is the lowest, and the dynamic grant resources are insufficient to accommodate the data corresponding to LCH1, the data corresponding to LCH4, and the data corresponding to LCH5, so that when the terminal device reassembles the data packet, only the data corresponding to LCH1 and the data corresponding to LCH4 are reassembled, and the data corresponding to LCH5 is continuously stored in the multiplexing and assembling entity.
In this scenario, the network device indicates whether each logical channel performs packet reassembly, so that the problem of data loss possibly caused by dynamic grant override configuration grant can be avoided. According to the data packet reorganizing method provided by the embodiment of the application, the terminal equipment can reorganize the data corresponding to the service or the logic channel with high priority stored in the HARQ buffer based on the logic channel priority process, so that the data newly transmitted by the terminal equipment by utilizing the dynamic grant resources comprises the data corresponding to the logic channel with high priority transmitted by the terminal equipment by utilizing the configuration grant resources, the data loss is avoided, and the data transmission efficiency is improved. And by configuring the first indication information corresponding to each logic channel, whether the data corresponding to the logic channel is subjected to data packet reorganization can be flexibly and accurately controlled according to the QoS requirement of the service. When the terminal equipment performs data packet reassembly, only the data corresponding to the logic channel needing to be retransmitted is needed to be considered, all MAC PDUs stored in the HARQ buffer are not needed to be reassembled, the waste of dynamic authorized resources is avoided, and the use efficiency of the dynamic authorized resources is improved.
In still other scenarios, for each MAC PDU, the network device sends first indication information to the terminal device, where the first indication information is used to determine whether the terminal device performs packet reassembly for the MAC PDU in case of transmitting data using the PDCCH scheduled dynamic grant resources.
In a specific implementation, the network device may send first indication information to the terminal device through an RRC message, e.g., the network device sends the first indication information to the terminal device through an RRC reconfiguration message, where the first indication information is used to indicate whether to perform packet reassembly for the MAC CE when transmitting data on the dynamic grant resource after transmitting data on the configured grant resource. Optionally, the first indication information may further indicate identification information of MAC CEs for reassembling the data packet, i.e. which MAC CEs are subjected to data packet reassembling.
If the configuration rebuild MAC PDU in the first indication information is in an on state, it can be determined that after the terminal device transmits data on the configuration authorized resource, if the terminal device receives scheduling information for scheduling uplink new transmission by using a PDCCH scrambled by the C-RNTI, the terminal device obtains information of MAC CEs transmitted on the configuration authorized resource, where the information of the MAC CEs may be all MAC CEs transmitted on the configuration authorized resource and the first indication information corresponding to each MAC CE. The terminal device determines a first MAC CE among all MAC CEs.
The number of the first MAC CEs can be one or a plurality of the first MAC CEs, first indication information corresponding to the first MAC CEs indicates that the first MAC CEs are subjected to data packet reorganization when being transmitted on dynamic grant resources after the first MAC CEs are transmitted on the configuration grant resources, data transmitted by the configuration grant resources this time comprise the first MAC CEs, and the data transmitted by the dynamic grant resources and the data transmitted by the configuration grant resources are aimed at the same HARQ process.
When the data packet is reassembled, the terminal device may acquire the first MAC CE stored in the HARQ buffer. And generating the MAC PDU for uplink transmission by the acquired data and the data existing in the multiplexing and assembling entity. The new MAC PDU utilizes PDCCH scheduled dynamic grant resource transmission. Wherein, the data stored in the HARQ buffer except the first MAC CE may be discarded.
In a scenario that the first indication information is specific to the MAC CE, as shown in fig. 5, the terminal device uses the configuration grant resource to transmit the first indication information corresponding to the first MAC CE to indicate packet reassembly, and stores the MAC PDU transmitted by using the configuration grant resource in the HARQ buffer. During the running period of the configuration authorization timer, if the terminal equipment receives the scheduling information of the uplink new transmission of the PDCCH which is scrambled by the C-RNTI and sent by the network equipment, the terminal equipment sends a first MAC CE stored in the HARQ buffer to a multiplexing and assembling entity, the multiplexing and assembling entity stores data corresponding to a logical channel 4 (LCH 4) and a logical channel 5 (LCH 5), and the terminal equipment generates the MAC PDU for uplink transmission from the acquired data corresponding to the LCH1 and the data stored in the multiplexing and assembling entity based on a logical channel priority process. In the embodiment of the application, the priority of the data corresponding to LCH5 stored in the multiplexing and assembling entity is lowest, and the dynamic authorization resource is insufficient to accommodate the data corresponding to LCH5 and the data corresponding to the first MAC CE, LCH4, so that when the terminal equipment recombines the data packet, only the data corresponding to the first MAC CE and LCH4 are recombined, and the data corresponding to LCH5 is continuously stored in the multiplexing and assembling entity. In other embodiments, if the dynamic grant resources are sufficient to accommodate the data corresponding to the first MAC CE and LCH4 and the data corresponding to LCH5, the terminal device reassembles the data packet, and performs packet reassembly on the data corresponding to the first MAC CE and LCH4 and the data corresponding to LCH 5.
In this scenario, whether each MAC CE performs packet reassembly is indicated by the network device, which may avoid the problem of data loss caused by dynamic authorization overlay configuration authorization. According to the data packet reorganizing method provided by the embodiment of the application, the terminal equipment can reorganize the data packets of the MAC CEs with high priority stored in the HARQ buffer based on the logic channel priority process, so that the data newly transmitted by the terminal equipment by utilizing the dynamic grant resources comprises the MAC CEs with high priority transmitted by the terminal equipment by utilizing the configuration grant resources, the data loss is avoided, and the data transmission efficiency is improved. In addition, by configuring the first indication information corresponding to each MAC CE, whether to carry out data packet reorganization on the MAC CE can be flexibly and accurately controlled according to the QoS requirement of the service. Because the terminal equipment only needs to consider the MAC CE needing to be retransmitted when carrying out data packet recombination, and does not need to recombine all MAC PDUs stored in the HARQ buffer, the waste of dynamic authorized resources is avoided, and the use efficiency of the dynamic authorized resources is provided.
In still other scenarios, for each logical channel and for each MAC CE, the network device sends first indication information to the terminal device, respectively, where the first indication information is used to determine whether the terminal device performs packet reassembly for data corresponding to the logical channel and whether to perform packet reassembly for the MAC CE when transmitting data using the dynamic grant resources scheduled by the PDCCH.
For example, the terminal device transmits logical channel 1 (LCH 1) and logical channel 3 (LCH 3) using the configuration grant resources, the first indication information corresponding to LCH1 indicates packet reassembly, the first indication information corresponding to LCH3 indicates that packet reassembly is not performed, and the terminal device uses the first indication information corresponding to the first MAC CE transmitted using the configuration grant resources to indicate packet reassembly, and the first indication information corresponding to the second MAC CE indicates that packet reassembly is not performed. If the terminal equipment receives the scheduling information of the uplink scheduling by using the PDCCH scrambled by the C-RNTI, which is sent by the network equipment, the terminal equipment sends the data corresponding to the LCH1 stored in the HARQ buffer and the first MAC CE to a multiplexing and assembling entity, wherein the multiplexing and assembling entity stores the data corresponding to the logical channel 4 (LCH 4) and the logical channel 5 (LCH 5), and the terminal equipment generates the MAC PDU for uplink transmission from the acquired data corresponding to the LCH1, the first MAC CE and the data stored in the multiplexing and assembling entity based on the logical channel priority process.
In the above embodiments of the present application, the HARQ process associated with the uplink new transmission scheduled by the network device is the same as the HARQ process associated with transmitting data on the configured grant resource. I.e. the transmission for dynamic grants corresponds to the same HARQ process as the transmission for configuration grants.
It should be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application.
In order to implement the above-mentioned data packet reassembling method, an embodiment of the present application provides a terminal device, and an optional component structure diagram of the terminal device 300 is shown in fig. 6, including:
a receiver 301, configured to receive scheduling information and first indication information for uplink new transmission when the terminal device transmits data on a configured grant resource and a configured grant timer is running;
The first indication information is used for determining whether packet reassembly is performed for transmission of the dynamic grant resources.
In some embodiments, the terminal device 300 further comprises:
A multiplexing and assembling entity 302 configured to reassemble the data packets if the first indication information is used to determine to reassemble the data packets.
In some embodiments, the terminal device 300 further comprises:
a first transmitter 303 is configured to transmit the reassembled data packet using the dynamically granted resources in the schedule information.
In some embodiments, the first indication information is carried in an RRC message.
In some embodiments, the first indication information is carried in an RRC reconfiguration message used for configuration Configure Grant Config.
In some embodiments, the configuration authorization configuration includes a first logical channel whose transmission reliability satisfies a first condition.
In some embodiments, the first indication information is carried in the scheduling information for uplink new transmission.
In some embodiments, the first indication information comprises first indication information for configuration authorization, wherein the first indication information is used for indicating whether data packet reorganization is performed when the data is transmitted on the dynamic authorization resource after the data is transmitted on the configuration authorization resource.
In some embodiments, the multiplexing and assembling entity 302 is further configured to obtain data in the MAC PDU stored in the hybrid automatic repeat request buffer, except for padding information.
In some embodiments, the first indication information includes first indication information for a logical channel;
The first indication information is used for indicating whether data packet reorganization is carried out on data corresponding to the logic channel when the dynamic grant resource is transmitted after the logic channel is transmitted on the configured grant resource.
In some embodiments, the first indication information is carried in an RRC reconfiguration message used for configuration Logical Channel Config.
In some embodiments, the terminal device 300 further comprises a first processor 304 configured to obtain information of a first logical channel transmitted on the configuration grant resource;
and after the first indication information corresponding to the first logic channel is indicated to be transmitted on the configuration authorized resource, carrying out data packet recombination on the data corresponding to the first logic channel when the first logic channel is transmitted on the dynamic authorized resource.
In some embodiments, the first logical channel comprises at least one logical channel.
In some embodiments, the multiplexing and assembling entity is configured to obtain data corresponding to the first logical channel in the MAC PDU stored in the hybrid automatic repeat request buffer.
In some embodiments, the data other than the data corresponding to the first logical channel in the MAC PDU stored in the hybrid automatic repeat request buffer is discarded.
In some embodiments, the first indication information includes first indication information for a MAC CE;
the first indication information is used for indicating whether the data packet is reorganized for the MAC CE when the data is transmitted on the dynamic grant resource after the data is transmitted on the configuration grant resource.
In some embodiments, the first indication information is further used to indicate identification information of a MAC CE of the reassembled packet.
In some embodiments, the terminal device 300 further comprises:
the second processor 305 is configured to obtain information of a first MAC CE transmitted on the configuration grant resource, where the first indication information corresponding to the first MAC CE indicates that, after the first MAC CE is transmitted on the configuration grant resource, packet reassembly is performed on the first MAC CE when the first MAC CE is transmitted on the dynamic grant resource.
In some embodiments, the first MAC CE includes at least one MAC CE.
In some embodiments, the multiplexing and assembling entity 302 is configured to obtain the first MAC CE in the MAC PDU stored in the hybrid automatic repeat request buffer.
In some embodiments, the multiplexing and assembling entity 302 is configured to receive data obtained by the terminal device from the MAC PDU stored in the hybrid automatic repeat request buffer;
based on the logical channel priority procedure, the acquired data and the data existing in the multiplexing and assembling entity are generated into a MAC PDU for uplink transmission in the multiplexing and assembling entity.
In some embodiments, the scheduling information for uplink new transmission includes scheduling the scheduling information for uplink new transmission using a C-RNTI scrambled PDCCH.
In some embodiments, the hybrid automatic repeat request process associated with the uplink new transmission is the same as the hybrid automatic repeat request process associated with transmitting data on the configured grant resources.
In order to implement the above-mentioned data packet reassembly method, an embodiment of the present application provides a network device, and an optional component structure diagram of the network device 400 is shown in fig. 7, including:
a second transmitter 401 configured to transmit scheduling information and first indication information for uplink new transmission;
The first indication information is used for the terminal equipment to determine whether to carry out data packet reorganization for the transmission of the dynamic authorized resource after the data is transmitted on the configured authorized resource.
In some embodiments, the first indication information is carried in an RRC message.
In some embodiments, the first indication information is carried in an RRC reconfiguration message used for configuration Configure Grant Config.
In some embodiments, the configuration authorization configuration includes a first logical channel whose transmission reliability satisfies a first condition.
In some embodiments, the first indication information is carried in the scheduling information for uplink new transmission.
In some embodiments, the first indication information comprises first indication information for configuration authorization, wherein the first indication information is used for indicating whether data packet reorganization is performed when the data is transmitted on the dynamic authorization resource after the data is transmitted on the configuration authorization resource.
In some embodiments, the first indication information includes first indication information for a logical channel;
The first indication information is used for indicating whether data packet reorganization is carried out on data corresponding to the logic channel when the dynamic grant resource is transmitted after the logic channel is transmitted on the configured grant resource.
In some embodiments, the first indication information is carried in an RRC reconfiguration message used for configuration Logical Channel Config.
In some embodiments, the first indication information comprises first indication information for MACCE;
the first indication information is used for indicating whether the data packet is reorganized for the MAC CE when the data is transmitted on the dynamic grant resource after the data is transmitted on the configuration grant resource.
In some embodiments, the first indication information is further used to indicate identification information of a MAC CE of the reassembled packet.
In some embodiments, the scheduling information for uplink new transmission includes scheduling the scheduling information for uplink new transmission using a C-RNTI scrambled PDCCH.
In some embodiments, the hybrid automatic repeat request process associated with the uplink new transmission is the same as the hybrid automatic repeat request process associated with transmitting data on the configured grant resources.
The embodiment of the application also provides a terminal device, which comprises a processor and a memory for storing a computer program capable of running on the processor, wherein the processor is used for executing the steps of the data packet reorganization method executed by the terminal device when the computer program runs.
The embodiment of the application also provides a network device, which comprises a processor and a memory for storing a computer program capable of running on the processor, wherein the processor is used for executing the steps of the data packet reorganization method executed by the network device when the computer program runs.
The embodiment of the application also provides a chip, which comprises a processor, wherein the processor is used for calling and running a computer program from a memory, so that the device provided with the chip executes the data packet reorganization method executed by the terminal device.
The embodiment of the application also provides a chip, which comprises a processor, wherein the processor is used for calling and running a computer program from a memory, so that the device provided with the chip executes the data packet reorganization method executed by the network device.
The embodiment of the application also provides a storage medium which stores an executable program, and when the executable program is executed by a processor, the method for reorganizing the data packets executed by the terminal equipment is realized.
The embodiment of the application also provides a storage medium which stores an executable program, and when the executable program is executed by a processor, the method for reorganizing the data packets executed by the network equipment is realized.
The embodiment of the application also provides a computer program product, which comprises computer program instructions, wherein the computer program instructions enable a computer to execute the data packet reorganizing method executed by the terminal equipment.
The embodiment of the application also provides a computer program product, which comprises computer program instructions, wherein the computer program instructions enable a computer to execute the data packet reorganizing method executed by the network equipment.
The embodiment of the application also provides a computer program, which enables a computer to execute the data packet reorganization method executed by the terminal equipment.
The embodiment of the application also provides a computer program, which enables a computer to execute the data packet reorganizing method executed by the network equipment.
Fig. 8 is a schematic diagram of a hardware composition structure of an electronic device (terminal device or network device) according to an embodiment of the present application, and the electronic device 700 includes at least one third processor 701, a memory 702, and at least one network interface 704. The various components in the electronic device 700 are coupled together by a bus system 705. It is appreciated that the bus system 705 is used to enable connected communications between these components. The bus system 705 includes a power bus, a control bus, and a status signal bus in addition to the data bus. But for clarity of illustration, the various buses are labeled as bus system 705 in fig. 8.
It is to be appreciated that the memory 702 can be either volatile memory or nonvolatile memory, and can include both volatile and nonvolatile memory. The nonvolatile Memory may be a ROM, a programmable read-Only Memory (PROM, programmable Read-Only Memory), an erasable programmable read-Only Memory (EPROM, erasable Programmable Read-Only Memory), an electrically erasable programmable read-Only Memory (EEPROM, ELECTRICALLY ERASABLE PROGRAMMABLE READ-Only Memory), a magnetic random access Memory (FRAM, ferromagnetic random access Memory), a Flash Memory (Flash Memory), a magnetic surface Memory, an optical disk, or a compact disk-Only Memory (CD-ROM, compact Disc Read-Only Memory), and the magnetic surface Memory may be a magnetic disk Memory or a tape Memory. The volatile memory may be random access memory (RAM, random Access Memory) which acts as external cache memory. By way of example, and not limitation, many forms of RAM are available, such as static random access memory (SRAM, static Random Access Memory), synchronous static random access memory (SSRAM, synchronous Static Random Access Memory), dynamic random access memory (DRAM, dynamic Random Access Memory), synchronous dynamic random access memory (SDRAM, synchronous Dynamic Random Access Memory), double data rate synchronous dynamic random access memory (ddr SDRAM, double Data Rate Synchronous Dynamic Random Access Memory), enhanced synchronous dynamic random access memory (ESDRAM, enhanced Synchronous Dynamic Random Access Memory), synchronous link dynamic random access memory (SLDRAM, syncLink Dynamic Random Access Memory), direct memory bus random access memory (DRRAM, direct Rambus Random Access Memory). The memory 702 described in embodiments of the present application is intended to comprise, without being limited to, these and any other suitable types of memory.
The memory 702 in embodiments of the application is used to store various types of data to support the operation of the electronic device 700. Examples of such data include any computer programs for operating on the electronic device 700, such as the application program 7022. A program for implementing the method of the embodiment of the present application may be contained in the application program 7022.
The method disclosed in the above embodiment of the present application may be applied to the third processor 701 or implemented by the third processor 701. The third processor 701 may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in software form in the third processor 701. The third Processor 701 may be a general purpose Processor, a digital signal Processor (DSP, digital Signal Processor), or other programmable logic device, discrete gate or transistor logic device, discrete hardware components, or the like. The third processor 701 may implement or perform the methods, steps and logic blocks disclosed in embodiments of the present application. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of the method disclosed in the embodiment of the application can be directly embodied in the hardware of the decoding processor or can be implemented by combining hardware and software modules in the decoding processor. The software module may be located in a storage medium located in the memory 702, and the third processor 701 reads information in the memory 702, in combination with its hardware, to perform the steps of the method as described above.
In an exemplary embodiment, the electronic device 700 may be implemented by one or more Application Specific Integrated Circuits (ASICs), DSPs, programmable logic devices (PLDs, programmable Logic Device), complex programmable logic devices (CPLDs, complex Programmable Logic Device), FPGAs, general purpose processors, controllers, MCUs, MPUs, or other electronic elements for performing the aforementioned methods.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
It should be understood that the terms "system" and "network" are used interchangeably herein. The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate that a exists alone, while a and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.
The above description is not intended to limit the scope of the application, but is intended to cover any modifications, equivalents, and improvements within the spirit and principles of the application.