Friday, July 15, 2016

Li-Fi


It’s impossible to avoid Wi-Fi in today’s world. It’s everywhere; your neighbors have it, it’s free in coffee shops, and essential for smartphones. We all know Wi-Fi, but what is Li-Fi? Li-Fi, like Wi-Fi, enables electronic devices like computers, laptops and smartphones to wirelessly connect to the Internet. Even though Wi-Fi was also originally intended for such devices, it is widely used today to connect all sorts of things: printers, televisions, speakers, headphones, and even running shoes! In simple terms, Li-Fi is equivalent to Wi-Fi, but using light waves instead of radio signals. Li-Fi uses the light waves from LED light bulbs – that are rapidly replacing incandescent light bulbs for their energy saving and safety - to transmit data so it provides illumination and wireless data communications. Imagine a modern LED light bulb – fitted with Li-Fi technology – in your living room, or office, or in a lamp on your desk, or by your bedside. Anywhere that is illuminated by the Li-Fi enabled LED, can also communicate via Li-Fi.

What Is LiFi?

The term LiFi was coined by Professor Harald Haas, and is recognized by the IEEE standardization committee for Optical Wireless Communications. LiFi is high-speed, bidirectional, networked and mobile wireless communications using light (as opposed to traditional radio frequencies). With LiFi technology, data travels in the visible light spectrum through LEDs.  This makes it possible to provide wireless internet access at speeds of over 100 Gbps, although this is still in the Lab. Although Li-Fi can be used to off-load data from existing Wi-Fi networks, implementations may be used to provide capacity for the greater downlink demand such that existing wireless or wired network infrastructure may be used in a complementary fashion.
LiFi is the use of the visible light portion of the electromagnetic spectrum to transmit information at very high speeds. This is in contrast to established forms of wireless communication such as Wi-Fi which use traditional radio frequency (RF) signals to transmit data.
With LiFi, data is transmitted by modulating the intensity of the light, which is then received by a photo-sensitive detector, and the light signal is demodulated into electronic form. This modulation is performed in such a way that it is not perceptible to the human eye.
LiFi is a category of Optical Wireless Communications (OWC). OWC includes infra-red and ultra-violet communications as well as visible light. However, LiFi is unique in that the same visible light energy used for illumination may also be used for communication.

How Does Li-Fi Work?
When a constant current is applied to an LED light bulb a constant stream of photons are emitted from the bulb which is observed as visible light. If the current is varied slowly the output intensity of the light dims up and down. Because LED bulbs are semi-conductor devices, the current, and hence the optical output, can be modulated at extremely high speeds which can be detected by a photo-detector device and converted back to electrical current. The intensity modulation is imperceptible to the human eye, and thus communication is just as seamless as RF. Using this technique, high speed information can be transmitted from an LED light bulb.
Radio frequency communication requires radio circuits, antennas and complex receivers, whereas Li-Fi is much simpler and uses direct modulation methods similar to those used in low-cost infra-red communications devices such as remote control units. Infra-red communication is limited in power due to eye safety requirements, whereas LED light bulbs have high intensities and can achieve very large data rates.


Ranjan Tyagi
Batch 2015-17
Symbiosis Institute of Telecom Management


Wednesday, July 13, 2016

SPECTRUM TRADING AND ITS IMPACT ON THE TELECOM SECTOR

Spectrum trading refers to trading of rights and obligations of a spectrum, which could be used for various communication needs including broadcasting, mobile telecom and emergency services. Spectrum trading will make telecom sector stronger. It allows the trading of unutilized spectrum. The major players of telecom sector Bharti Airtel, Vodafone India, Reliance Jio Infocomm and Idea Cellular will have spectrum in all areas whereas other small players may only have a regional presence. Hence they are getting the opportunity to exit the sector by selling their spectrum to bigger players.
Spectrum trading also helps the operator to choose their target area, by maintaining their presence, they can grow their market share there. It also leads to the disclosure of unutilized spectrum, which can be further used to grow infrastructure in their targeted areas of strategic importance. Considering spectrum as a natural resource, spectrum trading can lead us to efficient allocation of it compared to spectrum auction. As in spectrum auction there is high variance in price and also soaring prices is making remaining spectrum more expensive.
Telecom operators are trading unused spectrum to the operators who are facing spectrum congestion. In India, spectrum is considered a natural resource but it is relatively small which makes it a scarce resource. Hence spectrum trading will improve quality of service (QOS) and help the issue of call drops. It will also allow better spectrum usage. Hence customer satisfaction and service from the operators will improve. For instance, 800 MHz band, which uses CDMA technology can also have 4G services. So with the rise of 4G services in India one can trade a part of their 800 MHz band at a high price for 4G services. This escalates their revenue also.
Spectrum trading is considered as economically efficient because trade will only take place if spectrum is worth more to the new operator than the old one. As liberalization brings in new technologies and innovations to the market, trading allows better spectrum utilization. Hence trading is only effective when merged with liberalization. This factors provides customer with more choice. Moreover, spectrum trading uses natural resource of our country that is spectrum more effectively and with proper measures.

Devanshi Jhaveri
Batch 2016-18
Symbiosis Institute of Telecom Management

Should Social Media Monitoring be a part of Smart cities

In the present world, the lifetime of a company depends on how well it adapts to the changing requirements of their customers. Thus companies across various industries use a variety of methods to get information about the changing requirements of the customers and what people think about their brand. Social Media Monitoring is one such method that is being used by companies to get the necessary information.

Social Media Monitoring also known as Social Media Measurement involves monitoring of various social media platforms like Twitter, Facebook, blogs, online forums etc. for getting information about a brand and governing the volume and opinions of people about the brand online. As tons of conversations, articles and reviews are available online, monitoring social media provides the companies insight of the public’s opinion for their products/services and they will be able to anticipate the people’s expectation.

With the capability to reflect public opinions on various topics, social media monitoring finds its application in many places. Should smart cities be one such platform that make use of it?
Smart cities are urban regions that have advanced infrastructure, assured electricity supply and efficient transportation facilities. Multiple information and communication technology (ICT) solutions are integrated into a smart city to manage different organizations and their services in the city.

One of the major goals of a smart city is to involve the citizens in governance. Social media comes into the picture here. As most of the communications and discussions are happening over the social media platforms, using these platforms for involving the citizens in governance is a viable solution. Using this, cities can involve their citizens in several governing decisions like building and planning process, efficient urban mobility, health and education etc. The citizens can be involved in taking decisions that influence them.


The cities can also make use of social media monitoring to know whether their policies are generating a positive or negative response among the common mass, they can get feedback from the citizens on various issues and act accordingly.

The impact of social media monitoring in smart cities can best be explained by the experiment called Smart Santander. Santander is a city on Spain’s north coast with a population of 0.18 million. The Santander testbed is composed of several devices and sensors deployed at various locations. Through the deployed testbed, many services have been implemented. Some of them include:

Outdoor parking area management: Around 400 parking sensors were deployed at the main parking areas in the city. As a result, available parking sites were detected and citizens were given the information of them from time to time.

Santander City Brain: It enabled the people to share their ideas with other citizens. The citizens were also able to report about accidents, potholes or broken streetlights directly to the city hall.
Santander city experiment demonstrated the advantages of the IoT and social media monitoring by providing the residents with real time information about bus delays, parking availability etc. The citizens were made a part of the city’s governance using the social media as a platform. For better management and organising in the city and to make citizens involved in governance, social media monitoring could be made a part of smart cities.

Dereddy SabrinathReddy
Batch 2016-2018
Symbiosis Institute of Telecom Management