This white paper describes the technological features that are being developed to make voice over HSPA (VoHSPA) a reality. It describes the two potential options for VoHSPA. The first option leverages IP Multimedia Subsystem (IMS) technology developed in conjunction with Long Term Evolution (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 an HSPA infrastructure, and is referred to as CS Voice over HSPA (CSoHS).
This white paper originally published on 4G Americas website