Huawei and Qualcomm have completed an LTE FDD flash CSFB (Circuit Switched Fallback) voice call to UMTS using R9 protocol and Qualcomm’s Snapdragon S4 processor, the MSM8960, during a series of optimisation tests.
The tests, based on the flash CSFB voice service for the R9 protocol, resulted in low call setup latency than that of the R8 protocol, and close to that of a native UMTS voice call. During the CSFB testing, which also included LTE TDD calls, good call setup times were seen for both UMTS and GSM.
The introduction of R9 CSFB will further enhance users’ experiences and enable voice services on their LTE-based smartphones, through CSFB to GSM and UMTS. The joint CSFB testing was part of an ongoing cooperation between Huawei and Qualcomm on interoperability testing and optimisation involving GSM/UMTS/LTE TDD/FDD technologies.
Huawei’s LTE CSFB service has been commercially deployed in the Middle East, Asia Pacific, Europe and other regions, allowing users to access LTE data and voice services.