Challenging CDMA’s growing popularity in the 450 MHz bands in Europe, Ericsson and Nokia said today they would produce GSM infrastructure and handsets on the former analog radio frequencies.

Ericsson said it intends to expand its GSM portfolio into the 450 MHz bands and plans to have commercial products ready to support rollouts in 2006. “We believe that GSM will be the leading access technology supporting mass market services for a long time to come,” Ericsson GSM head Ulf Ewaldsson said in a statement. “GSM 450 is the next logical step in providing service to emerging growth markets.”

The move represents a change in trajectory for the world’s largest infrastructure provider, which has been mapping out its strategy in the 450 MHz bands with CDMA, but Ericsson shuttered its CDMA headquarters in San Diego earlier this year, and while it said it would remain in the business, it would scale back its global CDMA operations drastically.

Nokia’s plans for 450 MHz were much more vague. Today it issued a statement saying it would support GSM at those frequencies and “underlined” its interest in the technology. But it didn’t commit to any timeline for developing radio access equipment or handsets for those bands.

The 450 MHz bands were used for trunk radio services throughout Europe before the advent of the digital cellular revolution led by GSM. Spectrum holders, however, have been re-examining those bands as spectrum becomes scarce, and governments in both Europe and other regions of the world have been allotting new licenses in those high-propagation frequencies. Most new launches, however, have used CDMA technology due to CDMA’s smaller channel size, but alternate access providers like Flarion and IPWireless have developed products targeting the spectrum.