Patent Description:
Enhanced Ultra Reliable Low Latency Communication (eURLLC) puts forward higher requirements for transmission reliability and transmission latency. An end-to-end latency is even required to reach <NUM>.

In the present protocol version, for the retransmission of a Physical Uplink Shared Channel (PUSCH), a base station directly retransmits uplink data by scheduling a terminal.

An eURLLC service has a high requirement on a transmission latency, and the end-to-end latency is even required to reach <NUM>. The above retransmission method that the base station schedules the terminal cannot meet the latency requirement.

Related technology is known from <CIT>, <CIT>, "Design of uplink HARQ-ACK feedback for efeMTC (R1-<NUM>)", "Use of control region for eMTC Ues (R1-<NUM>)", "Use of control region for eMTC Ues (R1-<NUM>)", and "Introduction of enhancements for eMTC excluding EDT (R2-<NUM>)".

In order to more clearly illustrate technical solutions in embodiments of the disclosure, the accompanying drawings needed in the description of the embodiments are simply introduced below. It is apparent that the accompanying drawings in the following description are only some embodiments of the disclosure, for the ordinary skill in the art, some other accompanying drawings can also be obtained according to these on the premise of not contributing creative effort.

In order to make the purpose, technical solutions and advantages of the disclosure clearer, implementation modes of the disclosure will further be described below in combination with the drawings in detail.

A communication system and service scenarios described in the embodiments of the disclosure are intended to more clearly describe the technical solutions of the embodiments of the disclosure, and do not form a limit to the technical solutions provided in the embodiments of the disclosure. Those of ordinary skill in the art know that, with the evolution of communication system and the emergence of new service scenarios, the technical solutions provided in the embodiments of the disclosure are also applicable to similar technical problems.

<FIG> is a system structure diagram of a communication system according an exemplary embodiment of the disclosure. As illustrated in <FIG>, the communication system may include: an access network <NUM> and a terminal <NUM>.

The access network <NUM> includes several access network devices <NUM>. The access network device <NUM> and a core network device <NUM> communicate with each other through a certain interface technology, such as an S1 interface in the Long-Term Evolution (LTE) system and an NG interface in a New Radio (NR) system. The access network device <NUM> may be a base station, and the base station is an apparatus deployed in the access network to provide a wireless communication function for the terminal. The base station may include various forms of macro station, micro base station, relay station, access point, etc. In systems adopting different wireless access technologies, the device that functions as a base station may have different names. For example, in the LTE system, it is called eNodeB or eNB. In the <NUM> NR system, it is called gNodeB or gNB. As the communication technology evolves, the description of the term "base station" may change. Although the "base station" is used as an example in the embodiments of the disclosure, the base station may be understood as the access network device for providing user access function in each communication system.

The terminal <NUM> may include various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices which may be connected/coupled to a wireless modem and may have the wireless communication function, as well as various forms of User Equipment (UE), Mobile Station (MS), terminal device and etc. For the convenience of description, the devices mentioned above are collectively referred to as the terminal. The access network device <NUM> and the terminal <NUM> communicate with each other through a certain interface technology, such as a Uu interface.

Optionally, the communication system has a high requirement on transmission latency. For example, an uplink communication system supports an eURLLC service. In some embodiments, the eURLLC service requires an end-to-end latency to reach <NUM>.

A PDCCH bears Downlink Control Information (DCI) sent by the base station to the UE. At present, the DCI has eight DCI formats: DCI format 0_0, DCI format 0_1, DCI format 1_0, DCI format 1_1, DCI format 2_0, DCI format 2_1, DCI format 2_2, and DCI format 2_3.

The functions of the DCI born by the PDCCH include: scheduling a PUSCH, scheduling a PDSCH, indicating a Slot Format Indicator (SFI), indicating a Pre-emption Indicator (PI), and power control command. The specific DCI format and the included information are as follows.

Before the downlink control channel is introduced in detail, it is needed to define some basic concepts of downlink channel, specifically including a Control Channel Element (CCE)/search space/Resource-Element Group (REG)/REG bundle and Control-Resource Set (CORESET), etc. The CCE is a basic unit that forms the PDCCH, occupying <NUM> REGs on frequency domain resources. A given PDCCH may include <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> CCEs, and its specific value is determined by a DCI payload size and a required code rate. The number of CCEs that form the PDCCH is called an aggregation level. The base station may adjust the aggregation level of the PDCCH according to a wireless channel state actually transmitted so as to realize link adaptation transmission.

The aggregation level of the PDCCH actually sent by the base station is variable over time, and since there is no relevant signaling to inform the UE, the UE needs to blind detect the PDCCH at different aggregation levels. The PDCCH to be blind detected is called a candidate PDCCH. The UE will decode all candidate PDCCHs in the search space. If CRC passes, the content of the decoded PDCCH is considered to be valid for the UE, and information (such as scheduling indication, time slot format indication/power control command and the like) obtained by decoding is used for subsequent operations. In order to reduce the complexity of blind detection of the UE, it is needed to limit the set of CCE blind detected. The initial CCE sequence number of the candidate PDCCH needs to be able to be divisible by the number of CCEs of the candidate PDCCH.

The UE detects the PDCCH at limited CCE positions, thereby avoiding the increased complexity of blind detection, but this is not enough. In order to better control the complexity of blind detection in the NR, a control information format/aggregation level, the number of candidate control channels corresponding to the aggregation level, and a detection period of the search space in a time domain may be configured through high-level parameters. Based on the configuration information, the complexity of blind detection may be flexibly controlled. In short, not every DCI format needs to be blind detected in a candidate CCE set.

<FIG> is a flow chart showing an uplink transmission retransmission method according to an exemplary embodiment of the disclosure. The method may be performed by the communication system illustrated in <FIG>. The method includes as follows.

At Step <NUM>, a terminal sends uplink data to a base station on a first resource of a PUSCH.

At Step <NUM>, the base station receives the uplink data sent by the terminal on the first resource of the PUSCH.

At Step <NUM>, the base station generates feedback information of the uplink data, the feedback information including ACK or NACK.

When the uplink data is received successfully, the base station generates the ACK. When it is failed to receive the uplink data, or the uplink data is received but CRC of the uplink data fails, the base station generates the NACK.

At Step <NUM>, the base station sends the feedback information to the terminal using a first PDCCH format on a second resource of the PDCCH.

Optionally, the first PDCCH format is a PDCCH format designed for feeding back the ACK/NACK. An interval between the second resource and the first resource in a time domain dimension is less than a threshold value. Schematically, the threshold value is <NUM> symbols.

Optionally, the operation that "the feedback information is sent to the terminal using the first PDCCH format" may include: DCI including the feedback information is sent to the terminal, the DCI adopting the first PDCCH format.

At Step <NUM>, the terminal receives, on the second resource of the PDCCH, the feedback information sent by the base station using the first PDCCH format.

At Step <NUM>, when the feedback information is the NACK, the terminal retransmits the uplink data.

To sum up, in the method provided by the embodiment, by sending the feedback information (ACK or NACK) of the uplink data to the terminal using the first PDCCH format on the second resource of the PDCCH, the terminal can obtain the feedback information of the uplink data in the shortest possible time, and retransmit the uplink data when the feedback information is the NACK, thereby ensuring the timeliness of the retransmission process and thus meeting a latency requirement of an eURLLC service.

Step <NUM>, Step <NUM> and Step <NUM> may be implemented separately as an uplink transmission retransmission method on the terminal side, and Step <NUM>, Step <NUM> and Step <NUM> may be implemented separately as an uplink transmission feedback method on the base station side.

In an embodiment based on <FIG>, for Step <NUM> and Step <NUM>, the first PDCCH format is a PDCCH format designed for feeding back the ACK/NACK.

The first PDCCH format occupies X symbols on the PDCCH, where X is any value or a specified value in <NUM>, <NUM> and <NUM>. Any value means that the base station adopts any symbol of <NUM>, <NUM>, and <NUM> when transmitting the first PDCCH format. The specified value means limiting X to a constant fixed value, thereby reducing the complexity of blind detection to save the processing time of the terminal during the blind detection.

Optionally, the first PDCCH format is PDCCH format 2_4.

In an embodiment based on <FIG>, referring to <FIG>, the number of symbols d between the first symbol of the second resource on the PDCCH and the last symbol of the first resource on the PUSCH is not greater than K, where K is any value or a specified value in <NUM>, <NUM>, <NUM> and <NUM>.

In an optional embodiment based on <FIG>, for Step <NUM> and Step <NUM>, the CRC of the first PDCCH format is scrambled using an ACK-RNTI corresponding to the terminal. The ACK-RNTI may be the RNTI used only by the terminal, or it may be the identifier shared by the terminal and other terminals. When the ACK-RNTI is the identifier shared by n terminals, the first PDCCH format includes the ACK/NACK of the n terminals. That is, the first PDCCH format includes a feedback information sequence group, the feedback information sequence group includes n bits, and each bit corresponds to the ACK/NACK of a terminal, referring to the following embodiments.

At Step <NUM>, a base station determines a sequence position of feedback information of a terminal in a feedback information sequence group in a first PDCCH format.

The first PDCCH format is a PDCCH format provided by embodiments of the disclosure to feed back ACK or NACK. The PDCCH format may be PDCCH format 2_4.

When multiple terminals share the same ACK-RNTI, the base station needs to determine the sequence position of the feedback information of the present terminal in the feedback information sequence group.

Schematically, referring to <FIG>, it is set that the feedback information sequence group includes the feedback information of <NUM> terminals, that is, the feedback information sequence group includes <NUM> bits, and each bit corresponds to a piece of UE. If the present terminal is UE2, the sequence position of the UE2 is the second position in the feedback information sequence group.

At Step <NUM>, the base station configures a feedback position to the terminal.

The base station configures the feedback position to the terminal in, but not limited to, the following two manners.

In the first manner, the base station configures the sequence position to the terminal using a second PDCCH format on a PDCCH. The second PDCCH format is a PDCCH format used for configuring a first resource to the terminal. The second PDCCH format may be PDCCH format 0_0 or PDCCH format 0_1.

In the second manner, the base station semi-statically configures the sequence position to the terminal using RRC signaling.

At Step <NUM>, the terminal receives the feedback position configured by the base station.

Corresponding to the above step, the terminal receives the feedback position configured by the base station in, but not limited to, the following two manners.

In the first manner, the terminal receives the sequence position configured by the base station using the second PDCCH format on the PDCCH. At the same time, the terminal acquires scheduling information of the first resource from the second PDCCH format. The second PDCCH format may be understood as DCI using the second PDCCH format.

In the second manner, the terminal receives the sequence position semi-statically configured by the base station using the RRC signaling.

It is to be noted that Steps <NUM> to Step <NUM> are optional when multiple pieces of UE share the same ACK-RNTI.

At Step <NUM>, the terminal sends uplink data to the base station on a first resource of a PUSCH.

At Step <NUM>, the base station sends the feedback information to the terminal using the first PDCCH format on a second resource of a PDCCH.

The first PDCCH format is a PDCCH format designed for feeding back the ACK/NACK.

The first PDCCH format occupies X symbols on the PDCCH, where X is any value or a specified value in <NUM>, <NUM> and <NUM>. Any value means that the base station adopts any symbol of <NUM>, <NUM>, and <NUM> when transmitting the first PDCCH format. The specified value means limiting X to a constant fixed value, thereby reducing the complexity of blind detection to save the processing time of the terminal during the blind detection. The number of symbols d between the first symbol of the second resource on the PDCCH and the last symbol of the first resource on the PUSCH is not greater than K, where K is any value or a specified value in <NUM>, <NUM>, <NUM> and <NUM>.

In some embodiments, the base station may also send the DCI in the second PDCCH format on the second resource to directly schedule the terminal for retransmission.

At Step <NUM>, the terminal performs blink detection to the PDCCH within K symbols following the last symbol of the first resource.

At Step <NUM>, when the first PDCCH format is detected on the PDCCH, the feedback information sent using the first PDCCH format is received.

When a blind detection result is that the first PDCCH format is detected, the feedback information sent using the first PDCCH format is received. After receiving the feedback information, the terminal performs CRC to the first PDCCH format using its own ACK-RNTI, and after the CRC is successful, the terminal determines that it has received the feedback information from the base station.

Optionally, when the ACK-RNTI is the identifier shared by the terminal and other terminals, the terminal also determines the sequence position of its own feedback information in the feedback information sequence group, so as to extract its own feedback information from the feedback information sequence group.

Optionally, the terminal retransmits the uplink data on a specified resource. For example, the terminal retransmits the uplink data on a resource used for unauthorized transmission.

Correspondingly, the base station receives the uplink data retransmitted by the terminal.

At Step <NUM>, when a second PDCCH format is detected on the PDCCH, the uplink data is retransmitted according to a third resource scheduled using the second PDCCH format.

When the blink detection result is that the second PDCCH format is detected, the terminal may retransmit the uplink data according to the third resource scheduled using the second PDCCH format.

In the method provided by the embodiment, by including the feedback information sequence group in the first PDCCH format, the base station can simultaneously send the feedback information to multiple terminals, which is applicable to industrialization scenarios in the eURLLC, and can simultaneously feedback multiple industrialization terminals in the eURLLC.

The method provided by the embodiment may also combine ACK/NACK feedback and PDCCH scheduling retransmission, so as to obtain better compatibility with the communication systems in the related art.

It is to be noted that the steps performed by the terminal in the above embodiment may be implemented separately as an uplink transmission retransmission method on the terminal side, and the steps performed by the base station may be implemented separately as an uplink transmission feedback method on the base station side.

It is to be further noted that the above embodiments may also be freely split and/or combined into new embodiments by those skilled in the art, which is not limited.

The following are apparatus embodiments of the disclosure. For details not described in detail in the apparatus embodiments, refer to the above method embodiments in one-to-one correspondence.

<FIG> shows a block diagram of an uplink transmission feedback apparatus according to an exemplary embodiment of the disclosure. The apparatus may become part or all of the base station (or the access network device) through software, hardware, or a combination of the two. The apparatus includes: a receiving module <NUM>, a generating module <NUM> and a sending module <NUM>. The receiving module <NUM> and the sending module <NUM> may be hardware apparatus such as a radio frequency antenna and the like, and the generating module <NUM> may be hardware devices such as a central processor, a baseband processor or the like.

The receiving module <NUM> is configured to receive uplink data sent by a terminal on a first resource of a PUSCH.

The generating module <NUM> is configured to generate feedback information of the uplink data, the feedback information including Acknowledgement feedback (ACK) or Negative Acknowledgement feedback (NACK).

The sending module <NUM> is configured to send the feedback information to the terminal using a first PDCCH format on a second resource of a PDCCH.

In an embodiment, the first PDCCH format occupies X symbols on the PDCCH, where X is any value or a specified value in <NUM>, <NUM> and <NUM>.

In an embodiment, the number of symbols between the first symbol of the second resource and the last symbol of the first resource is not greater than K, where K is any value or a specified value in <NUM>, <NUM>, <NUM> and <NUM>.

In an optional embodiment, the first PDCCH format is PDCCH format 2_4.

In an optional embodiment, CRC of the first PDCCH format is scrambled using an ACK-RNTI corresponding to the terminal.

The ACK-RNTI is an identifier shared by the terminal and other terminals.

In an optional embodiment, the sending module <NUM> is further configured to configure the ACK-RNTI to the terminal.

In an optional embodiment, the apparatus further includes a determining module <NUM>.

The determining module <NUM> is configured to determine a sequence position of the feedback information in a feedback information sequence group in the first PDCCH format.

In an optional embodiment, the sending module <NUM> is further configured to configure the sequence position to the terminal using a second PDCCH format on the PDCCH, the second PDCCH format being PDCCH format 0_0 or PDCCH format 0_1, or semi-statically configure the sequence position to the terminal using RRC signaling.

<FIG> shows a block diagram of an uplink transmission retransmission apparatus according to an exemplary embodiment of the disclosure. The apparatus may become part or all of the terminals through software, hardware, or a combination of the two. The apparatus includes: a sending module <NUM>, a receiving module <NUM> and a processing module <NUM>. The receiving module <NUM> and the sending module <NUM> may be hardware apparatus such as a radio frequency antenna and the like, and the processing module <NUM> may be hardware devices such as a central processor, a baseband processor or the like.

The sending module <NUM> is configured to send uplink data to a base station on a first resource of a PUSCH.

The receiving module <NUM> is configured to receive feedback information sent by the base station using a first PDCCH format on a second resource of a PDCCH, the feedback information including Acknowledgement feedback (ACK) or Negative Acknowledgement feedback (NACK).

The processing module <NUM> is configured to retransmit the uplink data when the feedback information is the NACK.

In an optional embodiment, the processing module <NUM> is configured to perform blink detection to the PDCCH within K symbols following the last symbol of the first resource.

The receiving module <NUM> is configured to receive the feedback information sent using the first PDCCH format when the first PDCCH format is detected on the PDCCH.

In an optional embodiment, the processing module <NUM> is configured to perform CRC to the first PDCCH format using an ACK-RNTI.

The ACK-RNTI is an identifier shared by a present terminal and other terminals.

In an optional embodiment, the receiving module <NUM> is configured to receive the ACK-RNTI configured by the base station.

In an optional embodiment, the processing module <NUM> is configured to retransmit the uplink data according to a third resource scheduled using a second PDCCH format when the second PDCCH format is detected on the PDCCH.

In an optional embodiment, the processing module <NUM> is configured to determine a sequence position of the feedback information in a feedback information sequence group in the first PDCCH format.

In an optional embodiment, the receiving module <NUM> is configured to receive a second PDCCH format sent by the base station and the sequence position configured in the second PDCCH format, the second PDCCH format being PDCCH format 0_0 or PDCCH format 0_1. Or, the receiving module <NUM> is configured to receive RRC signaling sent by the base station, the RRC signaling being used for semi-statically configuring the sequence position.

<FIG> shows a structural schematic diagram of a terminal provided by an exemplary embodiment of the disclosure. The terminal includes: a processor <NUM>, a receiver <NUM>, a transmitter <NUM>, a memory <NUM> and a bus <NUM>.

The processor <NUM> includes one or more processing cores. The processor <NUM> runs a software program and module to perform various function applications and information processing.

The memory <NUM> is connected with the processor <NUM> through the bus <NUM>.

The memory <NUM> may be used for storing at least one instruction, and the processor <NUM> is used for executing the at least one instruction to implement the steps in the above method embodiments.

In addition, the memory <NUM> may be implemented by any type of volatile or non-volatile memory devices. The volatile or non-volatile memory devices include but are not limited to: a magnetic or optical disk, an Electrically Erasable Programmable Read-Only Memory (EEPROM), an Erasable Programmable Read-Only Memory (EPROM), a Static Random Access Memory (SRAM), a Read-Only Memory (ROM), a magnetic memory, a flash memory, and a Programmable Read-Only Memory (PROM).

In an exemplary embodiment, a computer-readable storage medium is also provided. The computer-readable storage medium stores at least one instruction, at least one program, a code set or an instruction set, which are loaded and executed by the processor to implement the uplink transmission retransmission method provided in the method embodiments.

<FIG> is a block diagram of an access network device <NUM> according to an exemplary embodiment.

The access network device <NUM> may include a processor <NUM>, a receiver1002, a transmitter <NUM> and a memory <NUM>. The receiver <NUM>, the transmitter <NUM> and the memory <NUM> are connected with the processor <NUM> through a bus respectively.

The processor <NUM> includes one or more than one processing core, and the processor <NUM> runs a software program and a module to execute the method executed by the access network device in the transmission configuration methods provided in the embodiments of the disclosure. The memory <NUM> may be configured to store the software program and the module. Specifically, the memory <NUM> may store an operating system <NUM> and an application program module <NUM> required by at least one function. The receiver <NUM> is configured to receive communication data sent by another device, and the transmitter <NUM> is configured to send communication data to the other device.

In an exemplary embodiment, a computer-readable storage medium is also provided. The computer-readable storage medium stores at least one instruction, at least one program, a code set or an instruction set, which are loaded and executed by the processor to implement the steps in the uplink transmission feedback method provided in the method embodiments.

Claim 1:
An uplink transmission feedback method, wherein the method comprises:
receiving (<NUM>), by a base station, uplink data sent by a terminal on a first resource of a Physical Uplink Shared Channel, PUSCH;
generating (<NUM>), by the base station, feedback information of the uplink data, the feedback information comprising Acknowledgement feedback, ACK, or Negative Acknowledgement feedback, NACK; wherein the NACK is configured to instruct the terminal to retransmit the uplink data; and
sending (<NUM>), by the base station, the feedback information to the terminal using a first Physical Downlink Control Channel, PDCCH, format on a second resource of a PDCCH;
wherein the first PDCCH format occupies X symbols on the PDCCH, where X is a specified value or any value in <NUM>, <NUM> and <NUM>;
wherein a number of symbols between a first symbol of the second resource and a last symbol of the first resource is not greater than K; where K is a specified value or any value in <NUM>, <NUM>, <NUM>, and <NUM>.