The journey of mobile telecom networks commenced in India with 2G GSM technology in 1995, when wireline telephone coverage was abysmally low. With 2G licences, wireless mobile operators rolled out networks which not only increased connectivity but also fuelled economic growth. With the entry of towercos since 2006, network expansions recorded massive growth. By 2010, the wireless subscriber base had crossed 690 million and teledensity had crossed 58 per cent.
In that era, radio access networks (RAN) comprised a base transceiver station (BTS) cabinet (macro BTS) installed in an air-conditioned shelter with operating temperatures below 300 °C. Then, with the introduction of 3G, innovations in technology brought in gradual change in the form factor of BTSs with higher energy efficiencies and high temperature tolerance in outdoor environments.
Around the year 2010, 3G universal mobile telecommunications system technology was deployed in Indian telecom networks to support data services. During that phase, original equipment manufacturers brought in a novel design which split the BTS into a tower-mounted remote radio unit and a baseband unit in a rack at base. The architecture (as shown in Fig.1) had RAN node connected with radio network controller (RNC) and backhaul with core network comprising a mobile switching centre (MSC), gateway GPRS support node, serving GPRS support node, etc.
Then, the advent of 4G long term evolution (LTE) technology brought substantially different internet protocol (IP)-based network architecture, which efficiently supported both voice and high speed data communications in India. This was the time when evolved node (eNode) RAN (as shown in Fig.2) brought in plug-and-play functionality, which eventually helped telcos in the reduction of both capex and opex due to ease of configuration management and network optimisation. In 2016, the first all new IP-based LTE network was rolled out by a telco, which also deployed outdoor small cells for densification, and capacity and coverage expansion. With subscribers increasing their data consumption, other telcos, in a competitive spirit, started focusing progressively on high speed 4G LTE roll-out rather than legacy 3G network expansion. The canvas of telecom networks started getting filled with a mix of macrocells and various types of small cells. Since then, small cells have become significant elements of heterogeneous telecom networks in India.
The Small Cell Forum identifies the small cell as a radio access point with main features such as low radio frequency (RF) power output, footprint and range.
Small cells with IP-based architecture and other superior features are the obvious choice of telcos for future upgradability to 5G. Small cells have accelerated the densification of networks for capacity and coverage of 4G LTE networks and are appropriate for coverage of public Wi-Fi, streets, buildings, malls, hotels, offices and institutions, etc. The contribution of small cells is evident from the fact that India is the world’s second-largest telecom market with a wireless subscriber base of 1,153 million and an average wireless data usage per subscriber per month of over 12 GB (as per TRAI data, as of December 31, 2020).
The ease of deployment of small cells has assisted value additions in the business of infrastructure sharing by infracos/fibercos/IP-I with telcos. Also, new companies (although not many) have emerged as neutral host providers in metros and large cities for in-building solutions and public Wi-Fi networks.
In terms of 5G readiness, India is trailing behind many other countries. Nonetheless, in the recently held auction by the Department of Telecommunications (DoT) in March 2021, telcos have not only shown interest but have also acquired sub-1 GHz and mid-band spectrum of a total value of Rs 770 billion. Further, DoT has allocated spectrum for 5G trials in the 3.5 GHz, 26 GHz and 0.7 GHz bands to telcos. The outcome of trials in the next few quarters will not only expedite the revision of the National Frequency Allocation Plan but also develop the ecosystem for supporting viable use cases. Going forward, in the next four-five years, small cells are likely to exceed the count of macro BTSs.
Adoption by end-user segments
It is an undeniable fact that the acceptance and success of any technology is driven by its technical and economic benefits when compared with alternatives. In comparison to macro BTS cell sites having high power consumption and large cell radius, small cells are extensively used for urban localities and street-level outdoor coverage via light poles or street furniture, and are also an effective solution for indoor coverage, along with the distributed antenna system (DAS), in hotels and airports.
Small cells are deployed for temporary events in public places with high data traffic. Fiberisation is the key to backhaul for high data traffic networks. Hence, small cell adoption would be higher when backhaul fiberisation is achieved on a large scale.
Small cells are the only option for important 5G deployment scenarios such as internet of things (IoT- and robotics-based manufacturing units with robotics, augmented reality (AR)/virtual reality (VR) and applications demanding very low latency (<1 mS).
For the objectives of energy efficiency as well as aesthetics, small cells are the preference in smart cities and upmarket townships.
Advantages and challenges
Small cell technology has many advantages:
- They are lightweight and have small form factors and therefore occupy very little space. This leads to an increased ease of mounting them on street furniture and light poles.
- They have a plug-and-play functionality, which makes them suitable for field workforces with average skill sets.
- They have high energy efficiency, which ensures low operating costs.
- They have 5G upgradability, which means they help build future-ready infrastructure.
- Their self-optimising network features help in reducing network healing costs and save manual efforts.
- Going forward, open RAN and software-defined network (SDN) features will lead to multi-vendor options and interoperability.
However, for the success of small cells, key challenges need to be addressed. The top challenge for the entire telecom industry is low ARPU across the industry (at less than $2 pm) which is substantially low vis-à-vis other countries of comparable gross domestic product (GDP). The other challenges are:
- The need for fiberisation, which involves a high capex of deployment. Further, fiberisation bears the right-of-way (RoW) permission fee burden for infracos.
- 5G spectrum costs, which are a financial burden for highly leveraged telcos.
- Millimetre wave spectrum is yet to be made available. This might lead to a delay in 5G roll-outs.
- Smart city public-private partnership (PPP) projects could lead to possible delays in large-scale investments from private players and sustainable business models.
- The traditional mindset of infrastructure providers with field workforce dependencies could lead to a need to transform operations by investing in and implementing solutions based on IoT, remote monitoring, data analytics and automation and suitably monetising through multiple revenue streams.
The way forward
Notwithstanding the challenges, there are positive drivers for the small cell market. Leading telcos have migrated from legacy 2G/3G technologies and have largely adopted modern IP-based 4G LTE network architecture, which has created a roadmap for 5G small cell deployment. In recent years, companies in the infrastructure provider space have emerged as neutral host providers and successfully showcased their capabilities as infracos while engaging with multiple telcos.
For fiberisation of telecom networks, the government’s BharatNet broadband project to lay 300,000 km of fibre and connect 250,000 gram panchayats has slowly but definitely progressed. This augmented network infrastructure by new fibercos is expected to be an enabler for 5G roll-outs.
With the pandemic, subscribers’ monthly data consumption is continuously rising. This has given a big boost to content creators and over-the-top applications. Thus, there are several developments which will act as growth drivers for improving the small cell market in the next three to five years, and small cells will be omnipresent in India.
By Tushar Kapadia, Telecom Infrastructure Consultant