# US 10,771,224 B2 · Method and device for transmitting feedback information

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- Number: US 10,771,224 B2
- Document ID: US10771224B2
- Status: Granted
- Kind: B2
- Application number: 16/088,434
- Filed: 2017-02-08
- Published: 2019-04-25
- Granted: 2020-09-08
- Earliest claimed: 2016-03-25
- Assignees: China Academy of Telecommunications Technology
- Applicants: China Academy of Telecommunications Technology
- Inventors: Xuejuan Gao; Xueming Pan; Fang-Chen Cheng; Qianqian Si
- Web page: https://patentgrep.com/patent/US10771224B2

## CPC

- H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)}
- H04L 1/1854: {Scheduling and prioritising arrangements}
- H04L 1/1864: {ARQ related signaling (H04L1/1607 takes precedence)}
- H04L 5/1469: {using time-sharing}
- H04L 27/2605: {Symbol extensions, e.g. Zero Tail, Unique Word [UW]}
- H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)

## Abstract

Disclosed in the present application are a method and device for transmitting feedback information, used to define new feedback timing for downlink data using a dynamic and variable TTI length during transmission, so as to ensure that ACK/NACK feedback information of downlink data is fed back on an earliest uplink transmission resource meeting a processing delay requirement, thereby reducing system delay. The method for transmitting feedback information provided in the present application comprises: receiving downlink transmission; and determining, at least according to a TTI length and/or a second TTI length of the downlink transmission, an uplink time-domain resource position for ACK/NACK feedback information transmission for the downlink transmission, and sending, on the uplink time-domain resource position, the ACK/NACK feedback information for the downlink transmission, wherein the second TTI length is configured by configuration signaling or is a pre-arranged TTI length used for determining the uplink time-domain resource position of ACK/NACK feedback information transmission.

## Claims

### Claim 1

A method for transmitting feedback information, the method comprising:
receiving downlink transmission; and
determining an uplink time domain resource position for transmitting Acknowledgement/Non-Acknowledgment (ACK/NACK) feedback information of the downlink transmission, according to at least a length of Transmission Time Interval (TTI) of the downlink transmission and/or a second length of TTI, and transmitting the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position;
wherein the second length of TTI is a length of TTI, configured by configuration signaling or predefined, for determining an uplink time domain resource position for transmitting ACK/NACK feedback information.

### Claim 2 (depends on 1)

The method according to claim 1, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission, and transmitting the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position, comprises:
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per the length of TTI of the downlink transmission, and an index of TTI of the downlink transmission is n; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L1*k or L2*k symbols;
wherein L1 is the length of TTI of the downlink transmission in a unit of time, L2 is the length of TTI of the downlink transmission in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction.

### Claim 3 (depends on 1)

The method according to claim 1, wherein the configuration signaling configures the second length of TTI as follows:
the configuration signaling indicates one of lengths of TTI in a predefined or preconfigured set of lengths of TTI for determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission as the second length of TTI; or
the configuration signaling indicates an offset between the second length of TTI and the length of TTI of the downlink transmission.

### Claim 4 (depends on 1)

The method according to claim 1, wherein:
the second length of TTI is an elementary short length of TTI, and the elementary short length of TTI is an elementary transmission unit in a time domain; or
the second length of TTI is one of a plurality of system supported lengths of TTI.

### Claim 5 (depends on 1)

The method according to claim 1, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and transmitting the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position, comprises:
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per a first length of TTI, and an index of TTI of the downlink transmission is n; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols;
wherein L3 is the first length of TTI in a unit of time, L4 is the first length of TTI in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction; and the first length of TTI is the second length of TTI, or a larger one or a smaller one or an average of the second length of TTI and the length of TTI of the downlink transmission.

### Claim 6 (depends on 1)

The method according to claim 1, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to at least the length of TTI of the downlink transmission and/or the second length of TTI, comprises:
determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and a feedback delay configured by the configuration signaling.

### Claim 7 (depends on 6)

The method according to claim 6, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and the feedback delay configured by the configuration signaling, comprises:
determining preliminarily an uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission according to the length of TTI of the downlink transmission and/or the second length of TTI; and
delaying the preliminarily determined uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the feedback delay configured by the configuration signaling, and determining the delayed uplink time domain resource position as a final uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission.

### Claim 8

A method for receiving feedback information, the method comprising:
transmitting downlink transmission; and
determining an uplink time domain resource position for transmitting Acknowledgement/Non-Acknowledgment (ACK/NACK) feedback information of the downlink transmission, according to at least a length of Transmission Time Interval (TTI) of the downlink transmission and/or a second length of TTI, and receiving the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position;
wherein the second length of TTI is a length of TTI, configured by configuration signaling or predefined, for determining an uplink time domain resource position for transmitting ACK/NACK feedback information.

### Claim 9 (depends on 8)

The method according to claim 8, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission, and receiving the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position, comprises:
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per the length of TTI of the downlink transmission, and an index of TTI of the downlink transmission is n; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L1*k or L2*k symbols;
wherein L1 is the length of TTI of the downlink transmission in a unit of time, L2 is the length of TTI of the downlink transmission in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction.

### Claim 10 (depends on 8)

The method according to claim 8, wherein the configuration signaling configures the second length of TTI as follows:
the configuration signaling indicates one of lengths of TTI in a predefined or preconfigured set of lengths of TTI for determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission as the second length of TTI; or
the configuration signaling indicates an offset between the second length of TTI and the length of TTI of the downlink transmission.

### Claim 11 (depends on 8)

The method according to claim 8, wherein:
the second length of TTI is an elementary short length of TTI, and the elementary short length of TTI is an elementary transmission unit in a time domain; or
the second length of TTI is one of a plurality of system supported lengths of TTI.

### Claim 12 (depends on 8)

The method according to claim 8, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and receiving the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position, comprises:
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per a first length of TTI, and an index of TTI of the downlink transmission is n; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determining to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols;
wherein L3 is the first length of TTI in a unit of time, L4 is the first length of TTI in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction; and the first length of TTI is the second length of TTI, or a larger one or a smaller one or an average of the second length of TTI and the length of TTI of the downlink transmission.

### Claim 13 (depends on 8)

The method according to claim 8, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to at least the length of TTI of the downlink transmission and/or the second length of TTI, comprises:
determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and a feedback delay configured by the configuration signaling.

### Claim 14 (depends on 13)

The method according to claim 13, wherein determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and the feedback delay configured by the configuration signaling, comprises:
determining preliminarily an uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission according to the length of TTI of the downlink transmission and/or the second length of TTI; and
delaying the preliminarily determined uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the feedback delay configured by the configuration signaling, and determining the delayed uplink time domain resource position as a final uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission.

### Claim 15

A device for transmitting feedback information, the device comprising at least one processor and a memory; wherein the memory is configured to store computer readable program codes, and the at least one processor is configured to execute the computer readable program codes to:
receive downlink transmission; and
determine an uplink time domain resource position for transmitting Acknowledgement/Non-Acknowledgment (ACK/NACK) feedback information of the downlink transmission, according to at least a length of Transmission Time Interval (TTI) of the downlink transmission and/or a second length of TTI, and to transmit the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position;
wherein the second length of TTI is a length of TTI, configured by configuration signaling or predefined, for determining an uplink time domain resource position for transmitting ACK/NACK feedback information.

### Claim 16 (depends on 15)

The device according to claim 15, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission, and to transmit the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position as follows:
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per the length of TTI of the downlink transmission, and an index of TTI of the downlink transmission is n; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L1*k or L2*k symbols;
wherein L1 is the length of TTI of the downlink transmission in a unit of time, L2 is the length of TTI of the downlink transmission in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction.

### Claim 17 (depends on 15)

The device according to claim 15, wherein the configuration signaling configures the second length of TTI as follows:
the configuration signaling indicates one of lengths of TTI in a predefined or preconfigured set of lengths of TTI for determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission as the second length of TTI; or
the configuration signaling indicates an offset between the second length of TTI and the length of TTI of the downlink transmission.

### Claim 18 (depends on 15)

The device according to claim 15, wherein:
the second length of TTI is an elementary short length of TTI, and the elementary short length of TTI is an elementary transmission unit in a time domain; or
the second length of TTI is one of a plurality of system supported lengths of TTI.

### Claim 19 (depends on 15)

The device according to claim 15, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and to transmit the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position as follows:
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per a first length of TTI, and an index of TTI of the downlink transmission is n; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to transmit the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols;
wherein L3 is the first length of TTI in a unit of time, L4 is the first length of TTI in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction; and the first length of TTI is the second length of TTI, or a larger one or a smaller one or an average of the second length of TTI and the length of TTI of the downlink transmission.

### Claim 20 (depends on 15)

The device according to claim 15, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to at least the length of TTI of the downlink transmission and/or the second length of TTI as follows:
determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and a feedback delay configured by the configuration signaling.

### Claim 21 (depends on 20)

The device according to claim 20, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and the feedback delay configured by the configuration signaling as follows:
determine preliminarily an uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission according to the length of TTI of the downlink transmission and/or the second length of TTI; and
delay the preliminarily determined uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the feedback delay configured by the configuration signaling, and determine the delayed uplink time domain resource position as a final uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission.

### Claim 22

A device for receiving feedback information, the device comprising at least one processor and a memory; wherein the memory is configured to store computer readable program codes, and the at least one processor is configured to execute the computer readable program codes to:
transmit downlink transmission; and
determine an uplink time domain resource position for transmitting Acknowledgement/Non-Acknowledgment (ACK/NACK) feedback information of the downlink transmission, according to at least a length of Transmission Time Interval (TTI) of the downlink transmission and/or a second length of TTI, and to receive the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position, wherein the second length of TTI is a length of TTI, configured by configuration signaling or predefined, for determining an uplink time domain resource position for transmitting ACK/NACK feedback information.

### Claim 23 (depends on 22)

The device according to claim 22, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission, and to receive the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position as follows:
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L1*k or L2*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per the length of TTI of the downlink transmission, and an index of TTI of the downlink transmission is n; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L1*k or L2*k symbols;
wherein L1 is the length of TTI of the downlink transmission in a unit of time, L2 is the length of TTI of the downlink transmission in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction.

### Claim 24 (depends on 22)

The device according to claim 22, wherein the configuration signaling configures the second length of TTI as follows:
the configuration signaling indicates one of lengths of TTI in a predefined or preconfigured set of lengths of TTI for determining the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission as the second length of TTI; or
the configuration signaling indicates an offset between the second length of TTI and the length of TTI of the downlink transmission.

### Claim 25 (depends on 22)

The device according to claim 22, wherein:
the second length of TTI is an elementary short length of TTI, and the elementary short length of TTI is an elementary transmission unit in a time domain; or
the second length of TTI is one of a plurality of system supported lengths of TTI.

### Claim 26 (depends on 22)

The device according to claim 22, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and to receive the ACK/NACK feedback information of the downlink transmission at the uplink time domain resource position as follows:
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK after a TTI with an index n+k, where TTIs are numbered as per a first length of TTI, and an index of TTI of the downlink transmission is n; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols, wherein the end time position or the end symbol position of the downlink transmission is determined according to a first length of TTI; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and satisfies a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is no earlier than a time length L3*k or L4*k symbols, after an end time position or an end symbol position of the downlink transmission; or
determine to receive the ACK/NACK feedback information of the downlink transmission over a first uplink time domain resource that can be used to transmit ACK/NACK and is spaced from an end time position or an end symbol position of the downlink transmission by no less than a time length L3*k or L4*k symbols;
wherein L3 is the first length of TTI in a unit of time, L4 is the first length of TTI in a unit of symbol, and k is a predefined or preconfigured positive integer or decimal fraction; and the first length of TTI is the second length of TTI, or a larger one or a smaller one or an average of the second length of TTI and the length of TTI of the downlink transmission.

### Claim 27 (depends on 22)

The device according to claim 22, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to at least the length of TTI of the downlink transmission and/or the second length of TTI as follows:
determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and a feedback delay configured by the configuration signaling.

### Claim 28 (depends on 27)

The device according to claim 27, wherein the at least one processor is configured to execute the computer readable program codes to determine the uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the length of TTI of the downlink transmission and/or the second length of TTI, and the feedback delay configured by the configuration signaling as follows:
determine preliminarily an uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission according to the length of TTI of the downlink transmission and/or the second length of TTI; and
delay the preliminarily determined uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission, according to the feedback delay configured by the configuration signaling, and determine the delayed uplink time domain resource position as a final uplink time domain resource position for transmitting the ACK/NACK feedback information of the downlink transmission.