Huawei touts 'ultra-flash' CSFB for faster call set-up times

Huawei said testing of what it calls "ultra-fast" circuit-switched fallback (CSFB) technology proved that the approach can shorten voice call set-up times by more than 50 percent for LTE networks and is even faster than traditional circuit-switched call setup times.

The Chinese vendor said it conducted a successful interoperability test of the technology, which it said is ready for commercial deployment on mobile networks and smartphones, at its Shanghai R&D facility. The test used Huawei's own radio access network (RAN) as well as evolved packet core (EPC) and circuit-switched core networks, plus test mobile phones embedded with Qualcomm (NASDAQ:QCOM) Technologies' MSM8974 processor.

CSFB, specified in 3rd Generation Partnership Project (3GPP) Release 8, enables devices in packet-switched LTE networks to transition to circuit-switched networks for incoming and outgoing voice calls as well as for text messaging. The successful deployment and use of CSFB has often been cited as one reason VoLTE has gotten off to a slow start overall, as provisioning of CSFB to support voice in an LTE environment has enabled operators to delay VoLTE deployments.

Huawei's interoperability test used its ultra-flash CSFB for TD-LTE fallback to GSM and LTE FDD fallback to WCDMA. According to Huawei, ultra-flash CSFB completes both caller and called phone fallbacks in only three seconds.

Huawei said it also tested several commercial smartphones running on Qualcomm Technologies' chipsets. Those test results proved it is unnecessary to modify smartphones to take advantage of the ultra-flash CSFB solution, the company said. Because ultra-flash CSFB relies upon a single radio voice call continuity (SRVCC) process, the only thing needed for the technology to work in commercial smartphones is SRVCC-enabled chipsets.

Huawei is marketing ultra-flash CSFB as a capex slasher, saying it "reduces CSFB deployment cost and complexity compared to standard solutions, which typically require upgrades to the entire 2G/3G radio network." The technology can also help operators smoothly evolve from CSFB to Voice over LTE (VoLTE)-enabled networks, the company said.

Huawei noted that as of December 2013, it has deployed 50 commercial CSFB contracts and won 14 commercial VoLTE network contracts. The company said it has submitted 12,686 LTE/EPC standards proposals to 3GPP, more than any other company.

For more:
- see this Huawei release

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