Telstra has switched on the high-definition (HD) voice capability for its NextG network.
This feature allows the telco’s customers that have a phone fitted with wideband adaptive multi-rate (AMR) codec to make phone calls with a higher voice quality to each other. Some phones have enhanced background noise cancellation as well.
HD voice has been in the making since Telstra commissioned Ericsson to built its third-generation mobile network in 2006. The network was made to be soft-switched and IP enabled.
Traditional phone calls are carried through narrowband frequencies which are had to be routed through older telephone networks.
HD voice is done purely through IP and transmits at a wider speech bandwidth which results in better voice all qualities carried at a 12.2kbps bit rate.
“Being IP end to end, we no longer have to go through intermediate point so we can actually set a call up from a device from one side of the country to another and they can transmit the bits between them without having to go back to another format,” Telstra wireless network and access technologies executive director, Mike Wright, said.
We call that a ‘transcoder-free’ operation and the wideband capability on the end allows customers to experience a greater range of frequencies.”
Calls do not use more capacity across the NextG network, according to the telco.
Covering about 2.1 million square kilometres, Telstra is claiming to have the largest HD voice footprint in the world.
So far, only a handful of handsets are HD voice enabled including Nokia N8, the HTC Desire S and Sony Ericsson Experia Play. By September, Telstra will have more than a dozen phones available with the new voice capability.
“A couple of hundred thousand” customers already have the ability to make HD voice calls. With average handset refresh rates of 18 months to two years in Australia, Telstra is expecting HD voice to have experience a natural penetration in the local market, just like SMS.
While other players in the telco industry have yet to introduce HD voice technology on their networks, Telstra expects his competitors to follow suit once it gains momentum. Then there will be talks of setting up gateways and interconnections to enable HD voice across different networks.
Supporting calls through HD voice also benefits Telstra’s network management.
“It simplifies management of the core of the network because traditionally, telephone networks were built to have routes, circuits and switches,” Wright said.
“When you have you added a new switch a fair bit of arrangement of the network had to be done and this is simplifying our core network.”