What is Carrier Aggregation?
Carrier Aggregation (CA) combines multiple component carriers (CCs) across different frequency bands or different parts of the same band to multiply peak data rates and improve spectral efficiency. Introduced in LTE-Advanced (3GPP Release 10), it is enhanced in 5G NR to support up to 16 aggregated carriers.
How Does Carrier Aggregation Work?
One carrier is designated the Primary Cell (PCell) which handles control signalling; additional carriers are Secondary Cells (SCells) adding throughput. Carriers can be intra-band contiguous (same band, adjacent), intra-band non-contiguous (same band, separated), or inter-band (completely different bands). In 5G, CA can combine FR1 and FR2 carriers for simultaneous sub-6 GHz + mmWave operation.
Use Cases
Achieving multi-Gbps peak rates by combining C-band and mmWave, utilizing fragmented spectrum holdings, boosting throughput for premium subscribers and fixed wireless access (FWA).
3GPP / Standards Reference
3GPP TS 38.300, TS 36.300 (LTE CA), Release 10 onwards
Related Terms
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