Nearly a decade after its debut, 3G has been widely deployed and supports over a billion subscribers. With the success of broadband, the 3G footprint continues to expand leading to an exponential increase in data traffic demand. The key question now is how can operators meet this demand? There is a limit to what operators can achieve with traditional methods of splitting the macro cells to meet traffic demand.
Today’s macro networks are typically designed to maximize data spectral efficiency with a model to service large file transfers. With increased adoption of smartphones and increased number of users on the network, the mix of data applications is changing drastically with numerous smaller transactions leading to a sizeable traffic volume. Interestingly, the traffic volume generated due to smartpones is even without any action taken by the user due to the signaling load. Also, with increased subscribers and data usage, there are other growing demands on macro networks to prioritize user applications based on aspects such as latency-sensitivity or the need to provide reasonable amounts of data during high load periods. It is essential to manage internal signaling mechanisms and macro network resources intelligently. Cellular architectures are generally designed to cater to wide coverage areas. User experience typically varies across the cell as the users move far from the base station mainly due to inter-cell interference and other constraints on the transmit power of the mobile devices. There are also known limitations with indoor signal penetration, particularly at higher frequencies. The presence of dead spots in certain areas and terrains exacerbates the problem with drastically reduced indoor coverage. To address these issues, there has been an increasing interest in deploying small cellular access points in residential homes, subways, offices and other areas where people congregate. These network architectures with small cells (microcells, picocells and femtocells) overlaying the macrocell network are termed as heterogeneous networks. These multi-tier networks can potentially improve spatial reuse and coverage by allowing cellular systems with innovative new topologies to achieve higher data-rates, while retaining seamless connectivity to cellular networks. For further insights continue reading this whitepaper.
