NSN Demonstrates First Circuit Switched over HSPA Call (CSoHSPA)

Finnish operator Elisa and Nokia Siemens Networks have successfully demonstrated the world's first circuit switched call over a high speed packet access network (CSoHSPA). The company said this new technology allows operators to simply and cost effectively increase voice capacity of their 3G networks, potentially up to 100%. The trial call was conducted in Elisa's live 3G network using R&D prototype devices supplied by Nokia.


Mobile systems such as GSM carry each voice call via a dedicated voice channel -- that is, circuit switching. The CS over HSPA feature carries voice calls over HSPA's packet-based transport channels instead.


While mobile users would see no difference in their voice service, the CSoHSPA technique, when supported by the continuous packet connectivity (CPC) features of 3GPP Release 7, requires far less handset battery power, providing a significant, potentially up to 50% increase in talk time.


The efficiency of CSoHSPA also means call setup times can be cut in half and operators benefit from much higher voice capacity per carrier, making it feasible for both consumers and operators to use 3G as the preferred network for making voice calls.


Nokia Siemens Networks said that to enable the technique in existing 3G networks, no changes are necessary to the core network and only a simple software upgrade is required in the radio access network.


"HSPA+ features are a needed and excellent step forward from current HSPA on the way to LTE. This demonstration of CSoHSPA shows one of the ways that consumer experience can be improved and makes 3G more attractive to consumers. Simultaneously operators need to ensure that they make most out of investments in traditional circuit switched networks, while embracing the advantages of HSPA evolution", said Keith Sutton, Head of the WCDMA/HSPA business in Nokia Siemens Networks.
http://www.nsn.com