3G: Call hand-over to GSM passes early tests
Nokia Corp. has followed Telefonaktiebolaget LM Ericsson in demonstrating call hand-over from new mobile broadband Internet networks to existing digital mobile networks.
On Friday, Nokia and Italian mobile operator Vodafone Omnitel SpA successfully performed a voice call hand-over between a 3G (third-generation) network, based on WCDMA (Wideband Code Divisional Multiplex Access) technology, and a voice-centric GSM (Global System for Mobile Communications) network, the Finnish mobile handset and infrastructure manufacturer said in a statement.
"The seamless interworking of WCDMA technology with a commercial GSM network
confirms that WCDMA networks are becoming ready for large-scale launches," said Tuula Putkinen, a spokeswoman for Nokia.
In September, Ericsson demonstrated call hand-over between a test 3G network set up by the vendor in Sweden using frequencies allocated to local operator HI3G Access AB and the commercial GSM network of Telia Mobile AB, according to Ericsson spokesman Peter Olofsson.
Call hand-over between 3G and GSM networks is crucial, especially in the early phase of 3G network deployment because coverage will be limited initially to metropolitan areas. Customers with dual-mode, 3G-GSM handsets who travel outside of 3G cells will be able to use their phones to make and receive calls on GSM networks without interruption.
Currently, call hand-over service is commercially unavailable in Europe because most operators are still in the early stages of building their 3G networks, said spokespeople from both Nokia and Ericsson.
Finland's Sonera Corp., which had hoped to launch commercial 3G service this year, has delayed service until the first half of 2003.
Austria's Mobilkom Austria AG & Co. KG., which is in a "soft" (experimental) 3G launch phase, doesn't yet provide call hand-over, said Olofsson. Ericsson supplies wireless equipment to Mobilkom.
"The pure complexity of having two different systems interact without dropping calls can't be underestimated," Olofsson. "There are many technical parameters that must work to avoid service interruption."
Some analysts have their doubts about the call hand-over tests. "Call hand-over has been demonstrated in the lab and now in tests involving the operators but it hasn't really been tested in the field with heavy traffic loads," said Bena Roberts, wireless analyst with Current Analysis Inc. "We won't know if this service really works until the 3G networks go live and generate traffic. I have my doubts."