Preparing for which generation?

Amidst the ongoing delay in the 3G auctions, the telecom regulatory authorities have already started bracing themselves for the way ahead ? 4G. With 3G auctions still in the doldrums, Telecom Regulatory Authority of India (Trai) has already started consultations for the next level of telecom services known as 4G, which offers download at a faster speed known as ultra-broadband and high definition video on demand among other such services.

In the guise of providing better network amidst scarcity of spectrum, the telecom operators have started preparing themselves for these technologies by upgrading their network capabilities. The telecom regulator?s move to leapfrog to 4G or long term evolution (LTE) technology comes in the wake of government dithering over 3G policy that has been delayed by more than three years. However, 2.5G, 3G and 4G have completely confused the subscribers and no one seems to have clarity on what distinguishes them. Starting from 1G, the world has gone a long way till 4G.

The high-speed access to voice and data technology is known as 3G service, as it is considered the third generation of cellular telecommunications technology. It offers advancements on the 1G (based on analog signals) and 2G (digital signals) networks such as multimedia applications like video and broadband services. LTE, which is an advancement over 3G promises faster speeds for mobile wireless users and lower costs and enhanced capacity for network providers.

2G networks were built mainly for voice services and slow data transmission. However, hardly any operator offered data on 2G. Some protocols, such as EDGE for GSM and 1x for CDMA2000, are defined as 3G services, but are considered as 2.5G services (or 2.75G) because they are several times slower than present-day 3G services.

2.5G is a stepping stone between 2G and 3G cellular wireless technologies. It does not necessarily provide faster services. 2.5G was evolved with an aim to offer data to the subscribers. The first major step in the evolution of GSM networks to 3G occurred with the introduction of general packet radio service (GPRS). So the cellular services combined with enhanced data transmission capabilities became known as 2.5G.

GPRS could be used for services such as Wireless Application Protocol (WAP) access, Multimedia Messaging Service (MMS), and for Internet communication services such as email and World Wide Web (WWW) access. GPRS data transfer is typically charged per megabyte of traffic transferred, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user actually is utilising the capacity or is in an idle state.

GPRS networks evolved to EDGE networks. EDGE was deployed on GSM networks beginning in 2003 ? initially by Cingular (now AT&T) in the United States. 3G service is based on standards developed by the International Telecommunications Union, known as the IMT-2000 criteria. Subscribers can expect faster data transfer speed up to 2 Mbps, better than dial-up and more in line with cable modem technology. Being a forerunner, the state-run BSNL and MTNL are already offering 3G services to their subscribers with little success.

The underlying technology between 3G and 4G is called 3.5G. This was just an up-gradation of 3G services where a user can expect a speed of about 1-3 Mbps while moving. 4G was a big leap after 3G. 4G is digital broadband packet based all IP technology. In other words, it is like sending voice over IP. It is known for a very high throughput of 3-5 Mbps when in motion.

Being based on an all-IP network infrastructure and using advanced wireless technologies such as MIMO, these specifications already display features characteristic for IMT-Advanced (4G), the successor of 3G. The US is moving from laggard to leader in 4G mobile, deploying LTE in re-farmed 700MHz TV spectrum. US-led global LTE momentum will influence Asian telecoms interests significantly. As Asia follows the US lead, re-farming TV spectrum for 4G, vendors and operators are likely to re-orient towards LTE, away from WiMAX/CDMA.

A report by HSBC says, ?India provides a good potential market for fixed WiMAX, given the limited wireline infrastructure, broadband penetration and relatively low data speed requirements of users. We have opted for a cautious stance and include WiMAX/4G capex or revenues in our Bharti forecasts. Wireless data is not a major driver in India today, given the combination of explosive subscriber growth, massive 2G voice capex, and limited spectrum.?

After a rough two years, mobile operators will look to increase their capital expenditure on improving their networks in 2010. ABI Research expects mobile capital expenditure to grow by more than 4% on a yearly basis in 2010, after contracting by 2.7% in 2009.

Driving this growth will be investments in 3.5G technologies such as HSPA and HSPA+, along with the rollout of 4G LTE networks by large operators such Verizon Wireless and Telia Sonera. The fastest growths in capital expenditures are expected to be in South America, with a compounded annual growth rate (CAGR) of 10% between 2009 and 2015.

Aggregate service revenue also bounced back in 2009, which will help fund the operators? capex plans in 2010. Globally, mobile service revenues grew 5.9% on a year-on-year basis between December 2009 and same period in 2008. ?The rapid adoption of smartphones will drive service revenue growth in 2010, as more consumers adopt data plans to take advantage of their handsets? features,? says analyst Bhavya Khanna.

LTE uses radio waves to allow more data to be transferred over the same bandwidth used by 3G equipment. As a result, service providers should be able to get more data transfer out of their existing cells and possibly lower the cost to run their networks. Since LTE connects to existing networks, providers can plan for a seamless transition then continue to use legacy CDMA and GSM networks as backups.

The way LTE achieves its speed could lead to a disadvantage: the start-up costs of service providers and consumers for equipment upgrades. LTE has adopted multiple-input multiple-output (MIMO) technology. As a result, cell base stations may need additional transmit and receive antennae. Mobile phones may have one transmit antenna and up to two receive antennae. Service providers may have to upgrade base stations, and consumers will need to buy new phones to utilise these upgraded networks.

Are we going to 5G? No! However, engineers worldwide are talking about gigabit wireless which will be the next big topic in the coming years.