4G Mini Towers on Street Lights, Traffic Lights & Trees!

The mission of making smart cities by Government of India refers to the addition of new technology and features to existing systems and making them more user friendly and sustainable. The first and foremost basic requirement for making a smart city is the robust IT connectivity. 4G and 5G would play an important role in ensuring this. The biggest challenge for 4G is the tower density which needs to be better than 2G/3G due to signal strength concerns. However, it is not an easy task in a country so big and diverse like India to add new equipment and set-ups as there could be challenges like huge infrastructure cost, lack of availability of space to deploy new infrastructure etc.

Recently Reliance Jio has installed 4G mini-towers in Mumbai using Ground Base Mast (GBM) which can be put up on existing street-light poles, Trees, traffic lights poles etc.

What is a Ground Base Mast (GBM)?
A Ground Base Mast is a freestanding structure which supports antennas at a height where they can transmit and receive radio waves. To minimize the environmental impact, it can be used in conjunction with street lights. These antennas provide small cell technology for 4G LTE output. GBMs do not require any air conditioning unlike traditional cell-site installation. Thus, it results in huge savings on power consumption. These are designed to typically consume just 600-700W of power. These pollution-free green telecom towers operate on lithium-ion batteries, thus eliminating the need for space and fuel-guzzling diesel generators.

How it works?
GBMs are deployed with small cell networks typically have cells that are a few meters in size and are deployed at street level, on light poles, buildings sides or other suitable structures as shown in the following figure. In these systems transmitted power split among several antenna elements, providing coverage over the same area as a single antenna system but at a reduced power level.

Small Cell Networks

Initial cell site deployment consists of a micro-base station with fiber centric backhaul. GBMs are fully integrated units containing a micro-base station, battery backup and switching – all within a small pole-mounted enclosure optimized for urban environments. The Distributed Antenna Systems (DAS) improve coverage and make more efficient use of spectrum.

Advantages:
1. A single unit to deploy means less cabling, simple alignment, and a rapid single-visit installation.
2. Sensors and metering systems can be deployed as Data-collection devices enable the city to generate information about its own infrastructure usage and condition.
3. Different types of networks (wireless Internet connection, radio frequency, GPRS, 3G, power line communication, and IP) connect these devices with a central data collection unit and the network allows data to be transported to a server.
4. Information from different places on the network has been collected at a central location, which can be further processed for extracting and observing any useful information.

Disadvantages:
1. Running fiber to street lights and other small cell sites could cost up to 50X more than a high capacity wireless backhaul solution.
2. Site availability, city layout and capacity requirements all influence the set up for GBMs.

By Lipika Gupta - HoD, ECE, Chitkara University H.P.