# US 10,484,922 B2 · Carrier-aggregation-based handover method

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

- Number: US 10,484,922 B2
- Document ID: US10484922B2
- Status: Granted
- Kind: B2
- Application number: 15/912,362
- Filed: 2018-03-05
- Published: 2018-07-12
- Granted: 2019-11-19
- Earliest claimed: 2010-04-29
- Assignees: Electronics and Telecommunications Research Institute
- Applicants: Electronics and Telecommunications Research Institute
- Inventors: Jae Heung Kim
- Web page: https://patentgrep.com/patent/US10484922B2

## CPC

- H04L 5/006: {Quality of the received signal, e.g. BER, SNR, water filling}
- H04L 5/001: {the frequencies being arranged in component carriers}
- H04W 36/0005: {Control or signalling for completing the hand-off}
- H04W 36/0027: {for a plurality of data sessions of end-to-end connections, e.g. multi-call or multi-bearer end-to-end data connections}
- H04W 36/00692: {using simultaneous multiple data streams, e.g. cooperative multipoint [CoMP], carrier aggregation [CA] or multiple input multiple output [MIMO] (allocation of physical resources in CoMP or in CA H04L5/0035)}
- H04W 36/0072: {of resource information of target access point}
- H04W 36/00835: {Determination of neighbour cell lists}
- H04W 36/00837: {Determination of triggering parameters for hand-off}
- H04W 36/302: {due to low signal strength}
- 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

Provided are a method for performing handover in a cellular mobile communication system that supports a carrier aggregation, and a user equipment and a node base (NodeB) using the method. A connection between the user equipment and the NodeB may be maintained and information may be exchanged using a plurality of serving carriers. Before performing the handover, the user equipment may perform measurement with respect to a neighboring NodeB supporting the carrier aggregation, and may provide parameter information to the NodeB in order to support a carrier aggregation function required for the handover. In a handover seamless environment, the continuity of a service may be provided and the performance of the service may be enhanced.

## Claims

### Claim 1

A communication method comprising:
receiving, from a user equipment (UE) through a first component carrier of an e-Node B (eNB), a measurement report, wherein the first component carrier is a primary component carrier and the measurement report comprises measurement results for the first component carrier and a second component carrier of the eNB;
after receiving the measurement report, transmitting, to the UE through the first component carrier, a command to use the second component carrier as the primary component carrier; and
after transmitting the command, receiving a preamble from the UE through the second component carrier,
wherein one or more component carriers, other than the second component carrier, supported by the eNB are deactivated when the preamble is received from the UE.

### Claim 2 (depends on 1)

The method of claim 1, wherein the command to use the second component carrier as the primary component carrier includes information on radio condition between the user equipment and the primary component carrier.

### Claim 3 (depends on 1)

The method of claim 1, wherein the preamble is received through a random access preamble channel (RACH) of the second component carrier,
and the method further comprises transmitting a random access response (RA response) to the UE after receiving the preamble.

### Claim 4 (depends on 3)

The method of claim 3, wherein the RA response comprises a Cell-Radio Network Temporary Identifier (C-RNTI).

### Claim 5 (depends on 1)

The method of claim 1, wherein the one or more component carriers comprises the first component carrier.

### Claim 6

A communication method comprising:
transmitting, from a user equipment (UE) through a first component carrier of an eNB, a measurement report, wherein the first component carrier is a primary component carrier and the measurement report comprises measurement results for the first component carrier and a second component carrier of the eNB;
after transmitting the measurement report, receiving, from the eNB through the first component carrier, a command to use the second component carrier as the primary component carrier; and
after receiving the command, transmitting a preamble from the UE through the second component carrier,
wherein one or more component carriers, other than the second component carrier, supported by the eNB are deactivated when the preamble is received from the UE.

### Claim 7 (depends on 6)

The method of claim 6, wherein the command to use the second component carrier as the primary component carrier includes information on radio condition between the user equipment and the primary component carrier.

### Claim 8 (depends on 6)

The method of claim 6, wherein the preamble is transmitted through a random access preamble channel (RACH) of the second component carrier,
and the method further comprises receiving a random access response (RA response) from the eNB after transmitting the preamble.

### Claim 9 (depends on 8)

The method of claim 8, wherein the RA response comprises a Cell-Radio Network Temporary Identifier (C-RNTI).

### Claim 10 (depends on 6)

The method of claim 6, wherein the one or more component carriers comprises the first component carrier.

### Claim 11

A communication apparatus, comprising:
a memory; and
a processor operably coupled to the memory,
wherein the processor, when executing program instructions stored in the memory, is configured to:
cause the communication apparatus to receive, from a user equipment (UE) through a first component carrier of the communication apparatus, a measurement report, wherein the first component carrier is a primary component carrier and the measurement report comprises measurement results for the first component carrier and a second component carrier of the communication apparatus;
cause the communication apparatus to, after receiving the measurement report, transmit, to the UE through the first component carrier, a command to use the second component carrier as the primary component carrier; and
cause the communication apparatus to, after transmitting the command, receive a preamble from the UE through the second component carrier,
wherein one or more component carriers, other than the second component carrier, supported by the communication apparatus are deactivated when the preamble is received from the UE.

### Claim 12 (depends on 11)

The apparatus of claim 11, wherein the command to use the second component carrier as the primary component carrier includes information on radio condition between the user equipment and the primary component carrier.

### Claim 13 (depends on 11)

The apparatus of claim 11, wherein the preamble is received through a random access preamble channel (RACH) of the second component carrier,
and the processor is further configured to transmit a random access response (RA response) to the UE after receiving the preamble.

### Claim 14 (depends on 13)

The apparatus of claim 13, wherein the RA response comprises a Cell-Radio Network Temporary Identifier (C-RNTI).

### Claim 15 (depends on 11)

The apparatus of claim 11, wherein the one or more component carriers comprises the first component carrier.

### Claim 16

A user equipment (UE), comprising:
a memory; and
a processor operably coupled to the memory,
wherein the processor, when executing program instructions stored in the memory, is configured to:
cause the UE to transmit, through a first component carrier of an eNB, a measurement report, wherein the first component carrier is a primary component carrier and the measurement report comprises measurement results for the first component carrier and a second component carrier of the eNB;
cause the UE to, after transmitting the measurement report, receive from the eNB through the first component carrier, a command to use the second component carrier as the primary component carrier; and
cause the UE to, after receiving the command, transmit a preamble from through the second component carrier,
wherein one or more component carriers, other than the second component carrier, supported by the eNB are deactivated when the preamble is received from the UE.

### Claim 17 (depends on 16)

The UE of claim 16, wherein the command to use the second component carrier as the primary component carrier includes information on radio condition between the UE and the primary component carrier.

### Claim 18 (depends on 16)

The UE of claim 16, wherein the preamble is transmitted through a random access preamble channel (RACH) of the second component carrier,
and the processor is further configured to receive a random access response (RA response) from the eNB after transmitting the preamble.

### Claim 19 (depends on 18)

The UE of claim 18, wherein the RA response comprises a Cell-Radio Network Temporary Identifier (C-RNTI).

### Claim 20 (depends on 16)

The UE of claim 16, wherein the one or more component carriers comprises the first component carrier.

### Claim 21

A wireless communication device for a user equipment (UE), comprising:
a memory; and
a processor operably coupled to the memory,
wherein the processor, when executing program instructions stored in the memory, is configured to:
cause the UE to transmit, through a first component carrier of an eNB, a measurement report, wherein the first component carrier is a primary component carrier and the measurement report comprises measurement results for the first component carrier and a second component carrier of the eNB;
cause the UE to, after transmitting the measurement report, receive from the eNB through the first component carrier, a command to use the second component carrier as the primary component carrier; and
cause the UE to, after receiving the command, transmit a preamble from through the second component carrier,
wherein one or more component carriers, other than the second component carrier, supported by the eNB are deactivated when the preamble is received from the UE.

### Claim 22 (depends on 21)

The device of claim 21, wherein the command to use the second component carrier as the primary component carrier includes information on radio condition between the UE and the primary component carrier.

### Claim 23 (depends on 21)

The device of claim 21, wherein the preamble is transmitted through a random access preamble channel (RACH) of the second component carrier,
and the processor is further configured to receive a random access response (RA response) from the eNB after transmitting the preamble.

### Claim 24 (depends on 23)

The device of claim 23, wherein the RA response comprises a Cell-Radio Network Temporary Identifier (C-RNTI).

### Claim 25 (depends on 21)

The device of claim 21, wherein the one or more component carriers comprises the first component carrier.