12. Carrier Aggregation (CA)

  1. SeungJune Yi,
  2. SungDuck Chun,
  3. YoungDae Lee,
  4. SungJun Park and
  5. SungHoon Jung

Published Online: 5 SEP 2012

DOI: 10.1002/9781118188545.ch12

Radio Protocols for LTE and LTE-Advanced

Radio Protocols for LTE and LTE-Advanced

How to Cite

Yi, S., Chun, S., Lee, Y., Park, S. and Jung, S. (2012) Carrier Aggregation (CA), in Radio Protocols for LTE and LTE-Advanced, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/9781118188545.ch12

Author Information

  1. LG Electronics, South Korea

Publication History

  1. Published Online: 5 SEP 2012
  2. Published Print: 5 SEP 2012

ISBN Information

Print ISBN: 9781118188538

Online ISBN: 9781118188545



  • carrier aggregation (CA);
  • MAC signaling;
  • primary cell (PCell);
  • secondary cell (SCell)


In carrier aggregation (CA), three different spectrum scenarios are considered such as intra-band contiguous CA, intra-band non-contiguous CA and inter-band non-contiguous CA. The most outstanding feature in the CA is that multiple serving cells are configured for the RRC_CONNECTED UE. The configured multiple serving cells (primary cell (PCell) and secondary cell (SCell)) are aggregated together to serve the UE. The PCell perform random access (RA) procedure, radio link monitoring (RLM), handover procedure and PUCCH transmission. The activation and deactivation of the SCell are realized by MAC signaling rather than RRC signalling. By using MAC signaling, the eNB can quickly change the activation/ deactivation status of the SCell in accordance with data activity, which improves UE battery consumption.

Controlled Vocabulary Terms

Communication system signaling; handover; media access protocol; multiaccess communication; secondary cells