Data traffic and usage on operator networks in India have grown manyfold over the past few years. The introduction of high speed 3G/4G services at affordable tariffs and the increased availability of low-cost smartphones are the key factors driving the data demand. While it promises a bright future for telecom operators in terms of business growth and profitability, managing the growing data de­mand is becoming a challenge. With most of the data usage taking place in­doors, the traditional operator focus on macrocell-based coverage is proving to be insufficient. Operators are, therefore, exploring other options such as Wi-Fi, small cells and in-building solutions to enhance indoor coverage and capacity to provide better access to high speed services. Inter­es­tingly, these options generate the best results when used in combination, thus bringing to light the importance of heterogeneous networks (HetNet).

HetNet is a combination of multiple networks, which helps manage data load in an efficient and effective manner and en­sure a seamless user experience. It is probably one of the best ways to deal with the increasing demand on existing spectrum. Alternative deployment models such as distributed antenna systems (DASs) and the emerging cloud radio access network (RAN) architecture are further adding to the heterogeneity in networks.

HetNets can put the available network capacity to efficient use, which, in turn, can give a major respite to users from call drops. Further, such networks can improve the quality of service and data throughput in the backhaul. In the past few years, operators in India have shown an inclination towards deploying HetNets for better network coverage. The deployments are set to gain traction in the coming years, with the number of connected devices growing manyfold. The rapid rise in over-the-top services and internet-of-things devices will result in 27 billion connected devices by 2020 globally, the majority of these belonging to the Indian market. This increased demand would require HetNets  to enhance customer experience. Wi-Fi offloading and small cells will play a bigger role in a HetNet environment. Small cells, carrier Wi-Fi, C-RAN and DAS investments together will account for nearly $13 billion by end-2016.

Increased operator activity

Wireless operators in India have increased their focus and investments in HetNet infrastructure in the past 12-15 months to cater to the growing capacity and coverage needs. Bharti Airtel is leveraging HetNet to better serve its customers. Its HetNet comprises macrocell sites, small cells, picocells and indoor and outdoor Wi-Fi points, which allow better coverage while keeping costs in check. The company had deployed a HetNet in Gurgaon while rolling out 4G services to provide better indoor coverage, which is still a challenge on the 2300 MHz band. Meanwhile, Reliance Jio Infocomm Limited (RJIL) has planned to leverage HetNet to enhance its 4G coverage. It plans to use a mix of macro sites, outdoor and indoor small cells, Wi-Fi access points and fibre to achieve higher capacity, network load balancing and enhanced user experience.

Wi-Fi forms an important part of the HetNet system. The space has seen much activity by operators in recent years. Bharti Airtel, Idea Cellular and Aircel are looking at Wi-Fi as an alternative for deployment in parallel with the existing macro base station network, making more spectrum available for data usage. In addition to developing individual Wi-Fi networks, Bharti Airtel and Vodafone India have come together to form an alliance, called Firefly Networks, to jointly bid for government Wi-Fi projects. Recently, the company installed a 24×7 Wi-Fi network at Delhi’s Karkar­d­ooma Court complex, with services currently being provided by Vodafone. Firefly Networks now plans to deploy Wi-Fi networks in the remaining five district courts in Delhi – Saket, Patiala House, Tis Hazari, Dwarka and Rohini – with connectivity from both Vodafone and Bharti Airtel. The company has also equi­p­p­ed the Supreme Court and the Delhi High Court with Wi-Fi connectivity. In addition, it has deployed Wi-Fi networks at the DLF and Pacific Malls, hospitals and private colleges in the Delhi-NCR region as well as in Khan Market. Mean­while, operators such as Tata Teleservices Limited and Bharat Sanchar Nigam Limited are experimenting to monetise their Wi-Fi networks. Reliance Commu­ni­­ca­­tions (RCOM) recently became the first operator in India to join the small-cell-as-a-service carrier-grade Wi-Fi network of Ozone Networks and Ericsson. This will enable the operator to utilise the existing Ericsson and Ozone Wi-Fi infrastructure and launch Wi-Fi services for a seamless end-user experience using the carrier-grade small-cell network. The partnership will enable RCOM to meet the growing customer expectations in ultra-dense environments by offloading data on to a Wi-Fi network.

Small cells are also an important component of HetNet systems. They are poised to increase in significance as the country witnesses increased data adoption. Bharti Airtel is in discussions with government bodies including the urban development ministry and resident welfare associations for the installation of 7,000-8,000 small cells at bus stops and street poles by end-2016. Vodafone is currently looking at deploying indoor solutions like small cells in some high-footfall areas.

Meanwhile, RJIL is reportedly planning to seek assistance from local cable operators for small-cell deployments given their reach and penetration in residential areas. It plans to deploy around 150,000 small cells across the country, a part of which will be deployed by local cable operators. This deployment will help RJIL enhance in-building access as its operations will be largely based on the 2300 MHz band, which has indoor penetration challenges. Currently, the work for developing a small-cell network is under way in 10 cities including Delhi, Mumbai and Kolkata.

HetNets help manage data load in an efficient and effective manner and ensure a seamless user experience. They are also one of the best ways to deal with the increasing demand on existing spectrum.

Issues and challenges

While HetNets seem to be a viable solution for managing the growing data demand given the inadequate spectrum base, they pose their own set of deployment and functional challenges for operators.

First, achieving economies of scale is a major challenge, which may prevent operators from undertaking nationwide implementation. The Indian telecom industry today faces a huge debt burden and high capital costs, which make big-ticket investments in technology extremely difficult. Moreover, as ARPUs continue to be low, a major turnaround in profitability is not possible in the near term.

Second, HetNets are likely to add to the complexity of charging and billing for services, thereby creating a conflict between end-users and service providers. Operators would have to revisit their operations and business support system capabilities to accommodate new network complexities. In addition, a HetNet environment will make it very difficult to isolate points of failure when faced with quality of service issues. Interference, hand­over and interoperating capabilities amongst the technologies will have to be given serious consideration.

The security issues relating to networks, devices and information are also likely to grow significantly. Security will become a key challenge in the public Wi-Fi hotspot space where multiple vendors and devices will be at play. Besides, the deployment and functional challenges associated with each of the HetNet components such as Wi-Fi and small cells will need to be taken into account separately.

Going forward

Given the surge in data usage, operators will have to turn to HetNets in a big way in the coming years. Currently, operators have started finding a strong business case in solutions such as small cells and Wi-Fi, but on a stand-alone basis. Going forward, as they roll out 4G services, they will have a growing need to leverage various existing as well as new network technologies and club them together to ensure a better user experience, which will drive the HetNet market.