Multi-Carrier HSPA Evolution

The HSPA Evolution will during the next decade be a key radio access technology for a cost-effective provisioning of mobile broadband services. In addition to the continuous improvements of WCDMA/HSPA in terms of spectral efficiency and latency, "multi-carrier operation" (or "carrier aggregation") for individual connections is now introduced. This paper presents the evolution of Multi-Carrier HSPA, discusses implications on network architecture & user equipment, and evaluates the achievable system performance (with focus on downlink). It is concluded that Multi-Carrier HSPA can be implemented at a low incremental cost; both in the radio access network, which already supports multiple carriers, and in terminals (due to synergies with LTE). Numerical results further show that achievable data rates of a Multi-Carrier HSPA system increase proportional to the number of carriers; in terms of peak physical layer data rates as well as (for bursty packet data) average user throughput. Thus, Multi-Carrier HSPA will be an attractive means for operators to provide higher data rates and decrease the production cost of mobile broadband access.