Speaking at the Gartner Mobile and Wireless summit in London, Gartner research vice-president Ian Keene said that five key wireless technologies are likely to emerge in the next five years to make the lives of anyone managing wireless networks even more complicated.

In the personal space, Bluetooth will be joined by Zigbee for low-power telemetry with batteries that last months or years.

Office wireless LANs will finally see 802.11n along side the b, g and sometimes a standards we have today. However, at 300MBPS, Wi-Fi N will require Gigabit Ethernet to the access point and in many cases new Power over Ethernet systems to deliver the increased power requirements needed. For the wide area network, a combination of copper, fibre and WiMAX will be creeping in. "Not WiMAX as mobile, but WiMAX as a fixed solution," he stressed.

For the mobile arena, today we have moved from GPRS to EDGE to WCDMA, pockets of HSDPA (High Speed Data Packet Access, sometimes called 3.5G) and the promise of HSUPA (High Speed Uplink Packet Access). In some parts of Asia and the United States, companies will also need a CDMA strategy. Then there is the future potential of WiMAX.

Despite the hype, 4G is still not here today and already it is questionable if it makes economic sense to invest in the backhaul for today's HSDPA and HSUPA mobile broadband.

802.16d fixed WiMAX might well die in the trough of disillusionment and be replaced by mobile WiMAX 802.16e in fixed installations which will deliver greater economies of scale.

Keene said that the entire mobile market was up until now driven by hype. Vendors are pushing new products to operators to invest a lot of money in scared that their competition will invest in it and succeed with something they do not have.

Today, the GSM family together has 79 percent of connections as of the end of 2006. This is significant as these operators will likely evolve with the GSM family to 3G WCDMA, HSPA and to LTE as they will need backward compatibility as their networks evolve.

For 3G, Gartner forecast that the GSM family would capture 89 percent of worldwide connections, some one billion by 2011. Meanwhile pre-3G GSM continues to grow in developing countries and the entire family will reach around four billion user by then.

However, the question is not just GSM versus CDMA, but there are emerging IP-based technologies such as WiMAX, municipal Wi-Fi and other proprietary stuff that is vying for the next 4G standard.

"4G. We don't know exactly what it is, but it is going to have an IP backplane, OFDM (orthogonal frequency division multiplex), software defined radio and MIMO (multiple in, multiple out)," he said.

Keene said that there were four main contenders for 4G today. There was Wi-Fi which was evolving beyond today's municipal hotspots to meet the technical descriptions of 4G; LTE, which was the obvious contender, UMB, Qualcomm's hope for 4G. though many operators were still weary of Qualcomm's licensing terms; and WiMAX. which he predicted would be the second 4G standard.

Keene said that one of the biggest problems with WiMAX in Europe would be its high operating frequency of 3.5GHz which would require more base stations and cause problems with in-building coverage, though the situation was improving with some 2.5GHz licenses now being issued.

However, he does not expect handsets to be available for some time. The first handsets will be expensive with terrible power consumption. For users and operators who do not wish to go through that phase, Gartner does not expect WiMAX handsets with comparable features to today's 3G handsets before 2011.

"WiMAX's problems are cutting the time advantage that Mobile WiMAX had over LTE," he said.

LTE (Long Term Evolution) may be ready by 2009 and because of this, Gartner does not expect to see too many existing mobile operators taking up WiMAX in their home market. However, for new entrants, or for established operators exploring new markets, WiMAX does have a role to play.

"We don't believe it (WiMAX) will be the leading 4G standard. We expect less than two percent of handsets will be WiMAX, but that is still a big market for manufacturers," he said.

The ITU has also defined 4G as 100 MBPS of highly-mobile use and 1 GBPS in a nomadic setup. However, delivering that level of connectivity will require a huge amount of spectrum.

In Europe today, 585 MHz of spectrum has been allocated, but the UMTS forum has forecasted that if everyone is to take advantage of 4G by 2020, another 1,200 to 1,700 MHz of frequency will need to be licensed.

"Where on earth is that going to come from?" he pondered.

Today, the ITU has approved bands in the 450 and 700 MHz range which have the added benefit of being able to travel long distances and penetrate walls, but still to get the amount of frequency needed, the industry expects to use the untapped 5 GHz spectrum which will have "atrocious" coverage and require huge investments in terms of base stations.

"4G is a technology in search of a business case. Vendors are developing 4G standards and rolling out prototype 4G networks, while mobile numbers are saturated and operators have trouble growing ARPU (average revenue per user).

"We can't say that 3G has been such a great success so can you give me billions more to invest in 4G. I can't see it happening," he said.