You've Heard of VoLTE; How About Voice over HSPA?

BELLEVUE, WA--(Marketwire - Feb 22, 2012) - 4G Americas, a wireless industry trade association representing the 3GPP family of technologies, today announced a new white paper, titled "Delivering Voice Using HSPA," that describes the technological features that are being developed to make Voice over HSPA (VoHSPA) a reality.

"There has been a lot of discussion regarding the anticipated launch of Voice over LTE, or VoLTE, services in the coming year. Now, similar opportunities are being developed for HSPA that allow operators to deliver Voice over HSPA," said Chris Pearson, President of 4G Americas. "Voice over HSPA could allow 3GPP operators significant flexibility by using packet-based technology to deliver voice, as HSPA serves to blaze the trail for mobile broadband and LTE gains significant momentum. Both mobile operators and consumers stand to benefit significantly from innovative, robust and efficient services like Voice over HSPA and VoLTE."

The report describes recent simulations that substantiate the benefits anticipated from VoHSPA. Chief among these are increases in the spectral efficiency of mobile networks. With these new techniques, voice calls can be delivered more efficiently from a spectral standpoint over Packet Switched (PS) rather than Circuit Switched (CS) networks freeing up radio resources for additional data traffic.

There are two potential options for VoHSPA described in the 4G Americas white paper. The first option leverages IMS technology developed in conjunction with LTE, and is referred to as IMS Voice over HSPA or simply IMS Voice. The other option delivers voice by modifying existing circuit-switch based techniques so that those communications can be transmitted over HSPA infrastructure, and is referred to as CS Voice over HSPA (CSoHS).

"Acronyms aside, there are substantial benefits that operators and mobile customers can derive from delivering voice using HSPA with IMS or modified circuit-switched techniques, in particular significant data capacity and battery life gains," said Bob Calaff, Director, Technology and Spectrum Strategy, T-Mobile USA and 4G Americas project leader for the white paper. "The good news is that virtually all of the features believed necessary for a robust VoHSPA service are either presently available or expected to be available from equipment vendors in the 2012 to 2013 timeframe for testing and validation."

The 4G Americas report defines work completed by the GSMA for a minimum mandatory set of features defined in existing 3GPP Release 8 specifications (IR 58: IMS Profile for VoHSPA) that should be implemented in order to ensure an interoperable, high quality, IMS-based telephony service over an HSPA radio access layer. In the white paper, 4G Americas recommends additional features, above the minimum mandatory features in IR 58, for VoHSPA either under an IMS or a CS approach, in order to minimize packet losses and variations in packet arrival times that can impair the quality of voice communications.

Pearson concluded, "Voice over HSPA continues to make great strides, and its full potential will involve a number of interrelated dependencies such as standardization, terminal and infrastructure enhancements, interworking, roaming and the maturation of the IMS ecosystem."

Delivering Voice Using HSPA was written collaboratively by members of 4G Americas and is available for free download at: www.4gamericas.org.

About 4G Americas: Unifying the Americas through Mobile Broadband Technology
4G Americas is an industry trade organization composed of leading telecommunications service providers and manufacturers. The organization's mission is to promote, facilitate and advocate for the deployment and adoption of the 3GPP family of technologies throughout the Americas. 4G Americas contributes to the successful commercial rollout of 3GPP mobile broadband technologies across the Americas and their place as the No. 1 technology family in the region. The organization aims to develop the expansive wireless ecosystem of networks, devices, and applications enabled by GSM and its evolution to LTE. 4G Americas is headquartered in Bellevue, Wash., with an office for Latin America and the Caribbean in Dallas. More information is available at www.4gamericas.org.