Foreword
Back in 2004, 3G mobile communication systems providing high-speed Internet access were available, such as HSPA. At that time, the introduction of HSPA was considered a key enabler for 3G systems to meet market demand and remain competitive against other systems for a number of years. Looking forward into the future, however, multimedia and ubiquitous traffic were expected to grow rapidly. To support future traffic growth and maintain competitiveness, many operators shared the strong intention to evolve the 3G system with a long-term perspective. Driven by these motivations, 3GPP started specification work for Long-Term Evolution based on the 3G system and completed the work in Release 8 specifications.
The advent of high-performance smartphones opened a new era of opportunities for service providers and customers in the mobile industry. The rapid adoption of smartphones motivated customers towards the experiences of rich multimedia services including broadband mobile Internet. As a result, mobile traffic has increased explosively in an unprecedented manner, often approaching the network capacity of the existing mobile network, which has given mobile operators a strong incentive to pursue more aggressive strategies for evolution of the mobile network.
With this in mind, LTE is the central focus of the mobile industry, as LTE is the most promising technology on the market. For mobile operators running GSM/UMTS systems, LTE is a natural choice for their future networks. ...
