# US 11,115,966 B2 · Beam failure recovery procedures using bandwidth parts

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

- Number: US 11,115,966 B2
- Document ID: US11115966B2
- Status: Granted
- Kind: B2
- Application number: 16/370,477
- Filed: 2019-03-29
- Published: 2019-10-03
- Granted: 2021-09-07
- Earliest claimed: 2018-03-30
- Assignees: Comcast Cable Communications, LLC
- Applicants: Comcast Cable Communications, LLC
- Inventors: Ali Cirik; Esmael Hejazi Dinan; Hua Zhou; Hyoungsuk Jeon; Alireza Babaei
- Web page: https://patentgrep.com/patent/US11115966B2

## CPC

- H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal
- H01M 10/48: Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569)
- H04B 7/0617: {for beam forming}
- H04B 7/0695: {using beam selection}
- H04B 7/06964: {Re-selection of one or more beams after beam failure}
- H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network
- H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA
- H04W 72/046: {the resource being in the space domain, e.g. beams}
- H04W 74/0833: Random access procedures, e.g. with 4-step access
- H04W 74/0836: with 2-step access
- H04W 74/0838: using contention-free random access [CFRA]
- Y02E 60/10: Energy storage using batteries
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H04B: TRANSMISSION
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

Systems, apparatuses, and methods are described for wireless communications. A wireless device may initiate a beam failure recovery (BFR) procedure using a bandwidth part (BWP) on a secondary cell. Based on initiating a random access procedure for the BFR procedure and/or based on unsuccessfully completing the BFR procedure, the wireless device may perform one or more operations to prevent and/or reduce misalignment between the wireless device and a base station.

## Claims

### Claim 1

A method comprising:
receiving, by a wireless device, one or more configuration parameters for a secondary cell, wherein the one or more configuration parameters indicate a plurality of bandwidth parts (BWPs) comprising a first BWP and a second BWP;
switching an active BWP of the secondary cell to the first BWP;
transmitting a preamble associated with a random access procedure for the secondary cell;
determining based on a quantity of uplink transmissions, that the random access procedure is unsuccessful; and
based on the determining that the random access procedure is unsuccessful, switching the active BWP of the secondary cell to the second BWP.

### Claim 2 (depends on 1)

The method of claim 1, wherein the one or more configuration parameters further indicate a duration for a BWP inactivity timer.

### Claim 3 (depends on 2)

The method of claim 2, further comprising:
based on the switching the active BWP of the secondary cell to the first BWP, starting the BWP inactivity timer; and
based on the transmitting the preamble associated with the random access procedure for the secondary cell, stopping, prior to the duration, the BWP inactivity timer.

### Claim 4 (depends on 1)

The method of claim 1, further comprising:
monitoring, based on a duration, for downlink control information (DCI) via a physical downlink control channel (PDCCH) of the first BWP.

### Claim 5 (depends on 1)

The method of claim 1, wherein the switching the active BWP of the secondary cell to the second BWP is further based on a determination that downlink control information (DCI) is not received via a physical downlink control channel (PDCCH) of the first BWP.

### Claim 6 (depends on 1)

The method of claim 1, wherein the random access procedure comprises a random access procedure for a beam failure recovery of the secondary cell.

### Claim 7 (depends on 1)

The method of claim 1, wherein the determining that the random access procedure is unsuccessful further comprises determining that downlink control information (DCI) is not received during a monitoring period.

### Claim 8

A method comprising:
receiving, by a wireless device, one or more configuration parameters for a secondary cell, wherein the one or more configuration parameters indicate:
a plurality of bandwidth parts (BWPs) comprising a first BWP and a second BWP; and
a duration for a BWP inactivity timer;
based on switching an active BWP of the secondary cell to the first BWP, starting the BWP inactivity timer;
transmitting a preamble associated with a random access procedure for the secondary cell;
based on the transmitting the preamble associated with the random access procedure for the secondary cell, stopping, prior to the duration, the BWP inactivity timer;
determining, based on a quantity of uplink transmissions, that the random access procedure is unsuccessful; and
based on the determining that the random access procedure is unsuccessful, performing one or more of:
restarting the BWP inactivity timer; or
switching the active BWP of the secondary cell to the second BWP.

### Claim 9 (depends on 8)

The method of claim 8, further comprising:
monitoring, based on the duration, for downlink control information (DCI) via a physical downlink control channel (PDCCH) of the first BWP, wherein the switching the active BWP of the secondary cell to the second BWP is based on a determination that the DCI is not received during the monitoring.

### Claim 10 (depends on 8)

The method of claim 8, wherein the random access procedure for the secondary cell comprises a random access procedure for a beam failure recovery of the secondary cell.

### Claim 11 (depends on 8)

The method of claim 8, wherein the determining that the random access procedure is unsuccessful further comprises determining that downlink control information (DCI) is not received during a monitoring period.

### Claim 12 (depends on 8)

The method of claim 8, wherein the first BWP is a non-default BWP of the secondary cell, and wherein the second BWP is a default BWP of the secondary cell.

### Claim 13 (depends on 8)

The method of claim 8, wherein the determining that the random access procedure is unsuccessful is based on an expiration of a beam failure recovery timer.

### Claim 14 (depends on 8)

The method of claim 8, wherein the transmitting the preamble associated with the random access procedure for the secondary cell comprises transmitting the preamble via an uplink resource.

### Claim 15

A method comprising:
receiving, by a wireless device, one or more configuration parameters for a secondary cell, wherein the one or more configuration parameters indicate:
a plurality of bandwidth parts (BWPs) comprising a first BWP and a second BWP; and
a duration;
switching an active BWP of the secondary cell to the first BWP;
transmitting a preamble associated with a random access procedure for the secondary cell;
monitoring, based on the duration, for downlink control information (DCI) via a physical downlink control channel (PDCCH) of the first BWP;
determining, based on a quantity of uplink transmissions, that the random access procedure for the secondary cell is unsuccessful; and
switching, based on a determination that the DCI is not received during the monitoring and based on the determining that the random access procedure for the secondary cell is unsuccessful, the active BWP of the secondary cell to the second BWP.

### Claim 16 (depends on 15)

The method of claim 15, wherein the switching the active BWP of the secondary cell to the second BWP is further based on a determination that the random access procedure is unsuccessful.

### Claim 17 (depends on 15)

The method of claim 15, wherein the duration is associated with an expiration of a BWP inactivity timer.

### Claim 18 (depends on 15)

The method of claim 15, further comprising:
based on the switching the active BWP of the secondary cell to the first BWP, starting a BWP inactivity timer associated with the duration; and
based on the transmitting the preamble associated with the random access procedure for the secondary cell, stopping, prior to the duration, the BWP inactivity timer.

### Claim 19 (depends on 15)

The method of claim 15, wherein the transmitting the preamble associated with the random access procedure for the secondary cell comprises transmitting the preamble for a beam failure recovery of the secondary cell.

### Claim 20 (depends on 15)

The method of claim 15, further comprises:
transmitting, via an uplink resource associated with the second BWP, the preamble associated with the random access procedure.