# US 2018/0027554 A1 · Techniques for communicating on an uplink in a shared radio frequency spectrum band

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2018/0027554 A1
- Document ID: US20180027554A1
- Status: Published application
- Kind: A1
- Application number: 15/605,707
- Filed: 2017-05-25
- Published: 2018-01-25
- Earliest claimed: 2016-07-21
- Assignees: QUALCOMM Incorporated
- Applicants: QUALCOMM Incorporated
- Inventors: Srinivas Yerramalli; Peter Gaal; Juan Montojo; Tao Luo; Wanshi Chen
- Web page: https://patentgrep.com/patent/US20180027554A1

## CPC

- H04W 72/0446: Resources in time domain, e.g. slots or frames
- H04L 1/0003: {by switching between different modulation schemes}
- H04L 1/0009: {by adapting the channel coding (H04L1/1812 takes precedence)}
- H04L 1/0013: {Rate matching, e.g. puncturing or repetition of code symbols}
- H04L 1/004: {by using forward error control (H04L1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M13/00)}
- H04L 1/18: Automatic repetition systems, e.g. Van Duuren systems
- H04L 1/1825: Adaptation of specific ARQ protocol parameters according to transmission conditions
- H04L 1/1861: {Physical mapping arrangements (for ACK signaling see also H04L5/0053)}
- H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)}
- H04L 5/005: {of common pilots, i.e. pilots destined for multiple users or terminals}
- H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal}
- H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals}
- H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)}
- H04W 16/14: Spectrum sharing arrangements {between different networks}
- H04W 28/0278: {using buffer status reports (dynamic wireless traffic scheduling definition H04W72/12)}
- H04W 52/0216: {using a pre-established activity schedule, e.g. traffic indication frame}
- H04W 52/146: {Uplink power control}
- H04W 52/367: {Power values between minimum and maximum limits, e.g. dynamic range}
- H04W 56/0005: {synchronizing of arrival of multiple uplinks}
- H04W 68/005: {Transmission of information for alerting of incoming communication}
- H04W 72/1268: of uplink data flows
- H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network
- H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal
- H04W 72/54: based on quality criteria
- H04W 74/006: {in the downlink, i.e. towards the terminal}
- H04W 74/085: {collision avoidance}
- H04Q 2213/13215: Code checking, CRC
- Y02D 30/70: in wireless communication networks
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- H04Q: SELECTING (switches, relays, selectors H01H; wireless communication networks H04W)
- Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE

## Abstract

Techniques are described for wireless communication. One method includes detecting a first reference signal received from a user equipment (UE) in a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) received over a shared radio frequency spectrum band; identifying a reference TTI in which the first reference signal is received; determining a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band; and transmitting an indication of the determined contention window size to the UE.

## Claims

### Claim 1

A method for wireless communication at a network access device, comprising:
detecting a first reference signal received from a user equipment (UE) in a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) received over a shared radio frequency spectrum band;
identifying a reference TTI in which the first reference signal is received;
determining a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band, the determined contention window size based at least in part on: a triggering of aperiodic channel state information (C SI) without a physical uplink shared channel (PUSCH) on the reference TTI, a decoding of a physical uplink control channel (PUCCH) with cyclic redundancy check (CRC) scheduled in the reference TTI, a decoding of a random access preamble scheduled on a physical random access channel (PRACH) in the reference TTI, a decoding of a first scheduled uplink transmission associated with a random access procedure and received in the reference TTI, or a combination thereof; and
transmitting an indication of the determined contention window size to the UE.

### Claim 2

An apparatus for wireless communication at a network access device, comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
detect a first reference signal received from a user equipment (UE) in a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) received over a shared radio frequency spectrum band;
identify a reference TTI in which the first reference signal is received;
determine a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band, the determined contention window size based at least in part on: a triggering of aperiodic channel state information (CSI) without a physical uplink shared channel (PUSCH) on the reference TTI, a decoding of a physical uplink control channel (PUCCH) with cyclic redundancy check (CRC) scheduled in the reference TTI, a decoding of a random access preamble scheduled on a physical random access channel (PRACH) in the reference TTI, a decoding of a first scheduled uplink transmission associated with a random access procedure and received in the reference TTI, or a combination thereof; and
transmit an indication of the determined contention window size to the UE.

### Claim 3

A method for wireless communication at a user equipment (UE), comprising:
receiving at least one uplink grant of a plurality of uplink grants for a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) transmitted over a shared radio frequency spectrum band, wherein at least a first uplink grant in the plurality of uplink grants includes: a first indication that the first uplink grant is associated with a first scheduled TTI of the reference scheduled transmission burst, a second indication of a position of the first scheduled TTI within the reference scheduled transmission burst, or a combination thereof;
transmitting during at least one TTI of the reference scheduled transmission burst, in accordance with the at least one uplink grant, the transmitting beginning during a first transmission TTI;
receiving an indication of a reference TTI, the reference TTI being used for transmission by the UE during the reference scheduled transmission burst; and
determining a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band, the determining based at least in part on a relationship between the first scheduled TTI, the reference TTI, and the first transmission TTI.

### Claim 4 (depends on 3)

The method of claim 3, wherein each uplink grant of the plurality of uplink grants for the reference scheduled transmission burst comprises an indication of the position of the first scheduled TTI of the reference scheduled transmission burst.

### Claim 5 (depends on 3)

The method of claim 3, wherein the indication of the reference TTI is relative to the first scheduled TTI.

### Claim 6 (depends on 3)

The method of claim 3, wherein the relationship includes the first transmission TTI being earlier than the reference TTI, the first transmission TTI being later than the reference TTI, or the first transmission TTI being the same as the reference TTI.

### Claim 7

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive at least one uplink grant of a plurality of uplink grants for a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) transmitted over a shared radio frequency spectrum band, wherein at least a first uplink grant in the plurality of uplink grants includes: a first indication that the first uplink grant is associated with a first scheduled TTI of the reference scheduled transmission burst, a second indication of a position of the first scheduled TTI within the reference scheduled transmission burst, or a combination thereof;
transmit during at least one TTI of the reference scheduled transmission burst, in accordance with the at least one uplink grant, the transmitting beginning during a first transmission TTI;
receive an indication of a reference TTI, the reference TTI being used for transmission by the UE during the reference scheduled transmission burst; and
determine a contention window size usable by the UE to contend for access to the shared radio frequency spectrum band, the determining based at least in part on a relationship between the first scheduled TTI, the reference TTI, and the first transmission TTI.

### Claim 8

A method for wireless communication at a user equipment (UE), comprising:
transmitting a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) over a shared radio frequency spectrum band;
identifying a hybrid automatic repeat request (HARQ) process corresponding to a reference TTI, wherein the reference TTI is a first TTI of the plurality of contiguous TTIs for which a HARQ acknowledgement is received;
identifying an instance of the HARQ process associated with a TTI subsequent to the reference TTI, wherein the instance of the HARQ process is identified based at least in part on: whether the TTI is included within the reference scheduled transmission burst or a subsequent transmission burst, whether the TTI includes aperiodic channel state information (CSI) without a physical uplink shared channel (PUSCH), or a combination thereof; and
determining a contention window size used to contend for access to the shared radio frequency spectrum band, the determining based at least in part on a state of a new data indicator (NDI) associated with the identified instance of the HARQ process.

### Claim 9

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
transmit a reference scheduled transmission burst including a plurality of contiguous transmission time intervals (TTIs) over a shared radio frequency spectrum band;
identify a hybrid automatic repeat request (HARQ) process corresponding to a reference TTI, wherein the reference TTI is a first TTI of the plurality of contiguous TTIs for which a HARQ acknowledgement is received;
identify an instance of the HARQ process associated with a TTI subsequent to the reference TTI, wherein the instance of the HARQ process is identified based at least in part on: whether the TTI is included within the reference scheduled transmission burst or a subsequent transmission burst, whether the TTI includes aperiodic channel state information (CSI) without a physical uplink shared channel (PUSCH), or a combination thereof; and
determine a contention window size used to contend for access to the shared radio frequency spectrum band, the determining based at least in part on a state of a new data indicator (NDI) associated with the identified instance of the HARQ process.

### Claim 10

A method for wireless communication at a user equipment (UE), comprising:
transmitting a type of buffer status report (B SR) including an indication of an amount of data to be transmitted for each of a plurality of listen before talk (LBT) priority classes;
receiving from a network access device, in response to transmitting the type of BSR, an indication of a LBT priority class boundary and an indication of a LBT priority class to be used by the UE when contending for access to a shared radio frequency spectrum band.

### Claim 11 (depends on 10)

The method of claim 10, further comprising:
selecting the LBT priority class based at least in part on a type of data to be transmitted over the shared radio frequency spectrum band and the LBT priority class boundary, wherein the LBT priority class boundary comprises at least one of: a highest LBT priority class usable by the UE, a lowest LBT priority class usable by the UE, or a combination thereof; and
contending for access to the shared radio frequency spectrum band based at least in part on the selected LBT priority class.

### Claim 12 (depends on 10)

The method of claim 10, further comprising:
selecting the type of BSR from a plurality of BSR types including at least first type of BSR and a second type of BSR.

### Claim 13 (depends on 12)

The method of claim 12, wherein the second type of BSR comprises a Long Term Evolution (LTE)/LTE-Advanced (LTE-A) type of BSR.

### Claim 14 (depends on 13)

The method of claim 13, wherein the first type of BSR is selected based at least in part on a BSR selection criterion.

### Claim 15 (depends on 14)

The method of claim 14, wherein the BSR selection criterion comprises receiving data to transmit, wherein the data is associated with a LBT priority class satisfying a threshold LBT priority class.

### Claim 16

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
transmit a first type of buffer status report (B SR) including an indication of an amount of data to be transmitted for each of a plurality of listen before talk (LBT) priority classes; and
receive from a network access device, in response to transmitting the first type of BSR, an indication of a LBT priority class to be used by the UE when contending for access to a shared radio frequency spectrum band.

### Claim 17

A method for wireless communication at a user equipment (UE), comprising:
receiving a first uplink grant for transmitting over a shared radio frequency spectrum band, the first uplink grant associated with a first listen before talk (LBT) priority class;
performing a first LBT procedure based at least in part on the first LBT priority class to contend for access to the shared radio frequency spectrum band, the first LBT procedure concluding at a LBT state;
determining, based at least in part on the LBT state, to not transmit over the shared radio frequency spectrum band in accordance with the first uplink grant;
receiving a second uplink grant for transmitting over the shared radio frequency spectrum band, the second uplink grant associated with a second LBT priority class; and
performing a second LBT procedure based at least in part on the second LBT priority class, the first LBT priority class, and the LBT state to contend for access to the shared radio frequency spectrum band.

### Claim 18 (depends on 17)

The method of claim 17, further comprising:
determining the first LBT priority class and the second LBT priority class are a same LBT priority class; and
initializing the second LBT procedure based at least in part on the LBT state.

### Claim 19 (depends on 17)

The method of claim 17, further comprising:
determining the first LBT priority class and the second LBT priority class are different LBT priority classes;
adjusting the LBT state based at least in part on a difference between the first LBT priority class and the second LBT priority class; and
initializing the second LBT procedure based at least in part on the adjusted LBT state.

### Claim 20

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive a first uplink grant for transmitting over a shared radio frequency spectrum band, the first uplink grant associated with a first listen before talk (LBT) priority class;
perform a first LBT procedure based at least in part on the first LBT priority class to contend for access to the shared radio frequency spectrum band, the first LBT procedure concluding at a LBT state;
determine, based at least in part on the LBT state, to not transmit over the shared radio frequency spectrum band in accordance with the first uplink grant;
receive a second uplink grant for transmitting over the shared radio frequency spectrum band, the second uplink grant associated with a second LBT priority class; and
perform a second LBT procedure based at least in part on the second LBT priority class, the first LBT priority class, and the LBT state to contend for access to the shared radio frequency spectrum band.

### Claim 21

A method for wireless communication at a network access device, comprising:
identifying feedback received from a user equipment (UE) for a downlink reference transmission time interval (TTI) of a transmission opportunity (TxOP) over a shared radio frequency spectrum band, the TxOP comprising at least one downlink TTI and at least one uplink TTI;
identifying an uplink TTI, of the TxOP, for which scheduling information is transmitted in the downlink reference TTI; and
determining a contention window size usable by the network access device to contend for access to the shared radio frequency spectrum band, for a next TxOP, based at least in part on the identified feedback and a scheduled uplink transmission in the identified uplink TTI.

### Claim 22 (depends on 21)

The method of claim 21, wherein determining the contention window size based at least in part on the scheduled uplink transmission in the identified uplink TTI comprises:
determining the contention window size based at least in part on a decoding of at least one channel including: a scheduled physical uplink shared channel (PUSCH), or a scheduled physical uplink control channel (PUCCH), or a scheduled physical random access channel (PRACH), or a combination thereof.

### Claim 23 (depends on 22)

The method of claim 22, wherein the determining the contention window size based at least in part on the decoding of the at least one channel comprises:
determining the contention window size based least in part on acknowledgement/non-acknowledgement (ACK/NACK) feedback for the at least one channel.

### Claim 24 (depends on 21)

The method of claim 21, wherein the at least one downlink TTI comprises at least one downlink subframe, and the at least one uplink TTI comprises at least one uplink subframe.

### Claim 25

An apparatus for wireless communication at a network access device, comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
identify feedback received from a user equipment (UE) for a downlink reference transmission time interval (TTI) of a transmission opportunity (TxOP) over a shared radio frequency spectrum band, the TxOP comprising at least one downlink TTI and at least one uplink TTI;
identify an uplink TTI, of the TxOP, for which scheduling information is transmitted in the downlink reference TTI; and
determine a contention window size usable by the network access device to contend for access to the shared radio frequency spectrum band, for a next TxOP, based at least in part on the identified feedback and a scheduled uplink transmission in the identified uplink TTI.

### Claim 26

A method for wireless communication at a user equipment (UE), comprising:
receiving scheduling information for an uplink transmission to be made over a plurality of carriers of a shared radio frequency spectrum band;
identifying a carrier of the plurality of carriers for which to perform a first type of listen before talk (LBT) procedure;
performing the first type of LBT procedure for the identified carrier;
performing a second type of LBT procedure for each carrier of the plurality of carriers other than the identified carrier, the second type of LBT procedure having a shorter contention window than the first type of LBT procedure; and
transmitting the uplink transmission over the plurality of carriers based at least in part on the performance of the first type of LBT procedure for the identified carrier and the performance of the second type of LBT procedure for each carrier other than the identified carrier.

### Claim 27 (depends on 26)

The method of claim 26, wherein identifying the carrier comprises one of: identifying the carrier from an indication received from a network access device, or independently identifying the carrier.

### Claim 28

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive scheduling information for an uplink transmission to be made over a plurality of carriers of a shared radio frequency spectrum band;
identify a carrier of the plurality of carriers for which to perform a first type of listen before talk (LBT) procedure;
perform the first type of LBT procedure for the identified carrier;
perform a second type of LBT procedure for each carrier of the plurality of carriers other than the identified carrier, the second type of LBT procedure having a shorter contention window than the first type of LBT procedure; and
transmit the uplink transmission over the plurality of carriers based at least in part on the performance of the first type of LBT procedure for the identified carrier and the performance of the second type of LBT procedure for each carrier other than the identified carrier.

### Claim 29

A method for wireless communication at a network access device, comprising:
scheduling an uplink transmission to be made by a user equipment (UE) over a plurality of carriers of a shared radio frequency spectrum band; and
transmitting, to the UE, an indication of a single carrier of the plurality of carriers for which to perform a first type of listen before talk (LBT) procedure.

### Claim 30 (depends on 29)

The method of claim 29, wherein transmitting the indication of the single carrier comprises: transmitting the indication of the single carrier in uplink downlink control information (DCI) for the single carrier, or transmitting the indication of the single carrier in uplink DCI for each carrier of the plurality of carriers.

### Claim 31

An apparatus for wireless communication at a network access device, comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
schedule an uplink transmission to be made by a user equipment (UE) over a plurality of carriers of a shared radio frequency spectrum band; and
transmit, to the UE, an indication of a single carrier of the plurality of carriers for which to perform a first type of listen before talk (LBT) procedure.

### Claim 32

A method for wireless communication at a user equipment (UE), comprising:
identifying a type of listen before talk (LBT) procedure to be performed for contending for access to a shared radio frequency spectrum band, the identified type of LBT procedure including a first type of LBT procedure or a second type of LBT procedure;
identifying an energy detection threshold associated with the identified type of LBT procedure, the identified energy detection threshold including a first energy detection threshold for the first type of LBT procedure or a second energy detection threshold for the second type of LBT procedure, wherein the first energy detection threshold is lower than the second energy detection threshold; and
performing the identified type of LBT procedure based at least in part on the identified energy detection threshold to contend for access to the shared radio frequency spectrum band.

### Claim 33

An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory in electronic communication with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
identify a type of listen before talk (LBT) procedure to be performed for contending for access to a shared radio frequency spectrum band, the identified type of LBT procedure including a first type of LBT procedure or a second type of LBT procedure;
identify an energy detection threshold associated with the identified type of LBT procedure, the identified energy detection threshold including a first energy detection threshold for the first type of LBT procedure or a second energy detection threshold for the second type of LBT procedure, wherein the first energy detection threshold is lower than the second energy detection threshold; and
perform the identified type of LBT procedure based at least in part on the identified energy detection threshold to contend for access to the shared radio frequency spectrum band.