The Broadband Conundrum

We live in an era of data deluge. We upload pictures of a birthday party to Facebook, Twitter, and Instagram simultaneously. If bandwidth permits, we also like to livestream the party to those who couldn’t attend. Mobile apps belonging to taxi aggregators like Ola and Uber gather data corresponding to thousands of rides everyday. When the astronauts go for a ‘space walk’, NASA wants to share the excitement by live streaming the event to those living on earth.

Studies suggest that our hunger for data is set to increase. This provides a great business opportunity and a great challenge for the telecom service providers. They want to cash in on this ever expanding realm of business, but are limited by technology options. Interestingly, the challenge lies not in transferring data over continents, but over the last few hundred miles.

Optical fibers: Still the king, but not at the doorstep

Despite phenomenal growth in mobile technologies, the good old optical fiber remains the best mode for high speed, high bandwidth data transmission. Whether we are connecting continents or connecting cities, they win hands down over other technologies. But, these rugged cables have a drawback: it is not economically viable to lay them over short distances from a home or village to the nearest fiber access point, say a few hundred metres to a couple of kilometers distance. It is not only, economically less viable to lay but also very costly to maintain these cables for last mile connectivity.

Copper: Data dies far too quickly

A time-tested way to overcome this limitation is to fall back to copper cables instead of optical fibers as one approaches the destination. This works pretty well as copper based technologies have advanced to support bandwidths up to 500 Mbps and beyond. However, copper cables work well only for short distances, say about half a kilometre. Other issues like signal degradation, and interference by electric and magnetic fields make copper unsuitable for long distance, high bandwidth data transmission.

Fixed wireless: Easy to set up, hard to rely on

One way to get over the problems of copper is to get rid of copper itself and use radio signals to provide internet. Called ‘fixed wireless’, this mode is preferred in places where laying cables, be it copper or optical fiber, is cumbersome and expensive. It provides decent internet even though the speeds are quite less than what is provided by optical fiber. However, the fact that fixed wireless operates in the unlicensed spectrum – a band of frequencies that can be used freely by anyone – makes it vulnerable to signal interference. Moreover, the quality and the speed of the internet comes down as the number of users served by a fixed wireless tower increase.

Riding the millimeter wave

Building networks that can support the rising demand for data transmission requires looking beyond copper cables and fixed wireless. A promising way forward is to transmit data in the form of high frequency electromagnetic waves (millimeter waves). Telecom service providers can operate in some of these bands upon paying a small but fixed licence fee and provide fiber-like internet. In many countries, a few bands in the millimeter range remain free for operation.

Unlike traditional data transmission techniques, millimeter waves carry data in highly focussed beams. They are free from interference and can provide quality internet to a large number of users. Once fully deployed, they will usher a new era of exciting technologies like connected cars, virtual reality classrooms, and the next generation of the internet of things.

Posted by:Sanjeev Shankar,Madhukara Putty