Huawei is developing an Ultra-Flash CSFB (Circuit Switched Fallback) voice solution to improve call setup times from LTE to GSM or UMTS.
After a smartphone on LTE places a voice call, Ultra-Flash CSFB allows the network to simultaneously send an indication to the smartphone to fallback from LTE to GSM or UMTS and to the circuit-switched core network to prepare resources for the smartphone. Standard CSFB solutions require first sending an indication to the smartphone and then accessing the GSM/UMTS network.
Huawei said testing at its Shanghai mLAB research center finds 20% faster call setup times compared to legacy GSM or UMTS network calls.
http://www.huawei.com/en/about-huawei/newsroom/press-release/hw-267387-csfb.htm
