Mobile Communication

There are three types of people in this world:

* Those that make things happen.
* Those that watch things happen.
* Those who wonder “what happened??”

Everyone agrees that wireless industry and economy, and most of the time the synergy between the two are making things happen, let us at least try to be among those watching rather than those wondering.

Pickup any newspaper or general magazine today, we are sure of finding an article some where relating to mobile communication and most of the time if not in technical section we find it in the business section. This is because of the simple reason that it is virtually affecting everyone’s life in one way or other. Some times it becomes a major political issue and some times an economic issue of immense importance.

Let us try to understand what is this “Mobile Communication” all about : what is its past, what is its present and what is its future and how it is going to change in future, the way we communicate today. We will also try to see how far this wave of changing scenario-affecting India.

Mobile communication in its simplest sense means ‘Communication while in move’ i.e.; the technology which enables us to communicate with rest of the world while we are in move is called mobile communication and this is the reason why it must be wireless unlike conventional telephones.

When we talk of wireless technology, it involves all types and forms of wireless mode of communication, one of them and perhaps the most challenging and dynamic one is mobile communication. Under the vast umbrella of wireless communication, the technologies like point-to-point wireless link, point-to-multipoint link, cordless telephony etc. also comes. But these are not mobile communication although wireless for the reason that these technologies do not allow (or deal with) seamless movement of the user over a large area i.e.; a city or a state or a country.

We will focus mainly on mobile communication and try to understand how mobile communication is going to change the very concept of communication, as we understand today.

Let us have a feel of the mobile communication system . It consists of a mobile terminal (MT), which the user carries along with him; the base station (BS) which communicates with MTs via wireless medium and MTSO (mobile telephone switching office) which is responsible for setting up all connections. The area covered by a BS is called a Cell. As a user moves from one cell to other, the system “handsoff” the call to the new cell. Multiple cells are used in order to accommodate more number of users (by a concept known as ‘frequency reuse’) and also to minimize the battery consumption of MT. This gives a generic view of mobile communication system, but this has been modified and changed over the decades in order to accommodate more features in more and more efficient ways.

Mobile communication like all other systems has evolved through number of generations: First generation (1G) is the past, Second generation (2G) is the present, Third generation (3G) is the near future; Fourth generation (4G) is the future. Also 2.5G, is the latest. First generation system was an analog technology based on a concept called FDMA(Frequency division multiple access) where each user is given a frequency band to communicate. It started way back in early eighties and even today it is popular in some parts of the world. In U.S. it is adhering to a family of standards called AMPS( Advanced Mobile Phone Service), in Europe it is TACS and in Japan JTACS. This generation of mobile phones were meant only for voice communication. Because of the limitations of analog technology and with digital revolution , the second generation of mobile communication came in to existence in early nineties. GSM ( Global system for mobile communication) is a classic example of 2nd generation mobile communication and is expanding at a rate of 10,000 subscribers a day on date. GSM is based on a concept known as TDMA(Time division Multiple access) . In 2nd generation also it was restricted mainly to voice communication but low data rate services were introduced. SMS(Short Message Service) is an example of low data rate services and today we experience the massive growth of SMS application. This is one of the most popular services especially among the younger generations and in many places of the world the GSM system hangs due to excessive use of SMS on special days like 14th of Feb. With the increasing popularity of data services and internet boom, 2.5G was introduced which allows the access of internet through mobile phones using a technology called WAP( Wireless Access Protocol) up to a data rate of 15-70Kbps.

With the extreme popularity of internet , people got used( or addicted ) to it and started expecting of using internet and downloading huge MP3 files in seconds while moving at a speed of 200Km per hour. All these were not possible with 2G or 2.5G and that’s how 3G was thought of. 3G mobile system will support other than voice, video telephony , video games, multimedia, net-browsing, network games, email, downloading, all these while moving at a speed of 200Km/hr and at a very high data rate. 3G will allow a user to talk to some one at the same time download huge MP3 files. Above all these, some thing call ‘location based services’ will be possible, i.e.; using the 3G mobile phone, the user will be able to get all information regarding near by hotels, restaurants, places of visits etc. when he is walking through the streets of an unknown city surrounded by unknown faces. Also when a user will make an emergency call, his location will be automatically found out by police or hospitals so that he can be assisted immediately. All these and many more innovative services will be provided by 3G mobile communication system. 3G system is based on CDMA(Code division multiple access). The beginning of convergence of communication and computing is the central to the idea of 3G system. It is expected to be operational by 2003-2004 in some parts of the world. But a global standard for 3G was also not possible due to high profile lobbing of U.S. and Europe, this means that the user of 3G mobile phone may not be fortunate enough to use the same phone in all parts of the world and get access to these innovative and high end services.

There is no limit to human ambitions. We have already seen the range of killer applications those will be provided by 3G system, but concepts of 4G(the future generation of Mobile Communication System) has already started evolving, although 3G itself is expected 1-2 years down the line. The migrations from 1G to 2G and 2G to 3G are perhaps evolution but migration from 3G to 4G as many think, will be a revolution rather than evolution both from technological and user perspectives. 4G network today is only an evolving concept, there is no real definition of what 4G will be. The concept of convergence has already began with 3G , 4G will bring about convergence of communication, computing, broadcasting etc. Today a normal urban person is his daily life uses a phone(fixed or mobile), computer, TV, Music system, Radio, Video camera , digital dairy , door locking system etc. etc. . But today there is no linkage between them i.e.; for a user these all are different equipments and to be used independently and separately. The whole idea of 4G is to have automated and autonomous machine-to-machine interaction between all the above mentioned and all other equipments. Different equipments are used by people at different places e.g.; TV is used at home, high end computer at workplace and so on. In future the devices will interact among themselves as the user arrives at home for example, they will form a home area network. Similarly as the user moves to workplace , the devices will interact automatically among themselves and will form Office Area Network and in most cases without the knowledge or intervention of the user. As a person moves between environments, the personal profile and preferences will move with him i.e.; suppose a person moves to a hotel room , TV channel will be changed automatically as per that person’s preference which he watches at home and these will be possible without intervention of the user. Thus we can visualize 4G as two level of communication : Communication between MT and all equipments like TV etc. inside a room and the communication between MT and base station(i.e. with outside world) as in previous generations of systems. In future we can see an increasing trend of personal mobile assistants which will almost transparently do credit card payment, online shopping with very little inputs from the user. The heart of all these converged and automated environments are “embedded radio” and “pervasive computing”. Embedded radio conceptualises the presence of single chip radio embedded in all equipments like TV, Mobile, Digital camera etc. so that they can communicate among them selves. The concept of “pervasive computing” is being promoted by computer scientists for decades which essentially theorizes that computing devices will be embedded virtually in everything and all those computing devices will be able to share information. Internet has accelerated interest in pervasive computing ; wireless network which can support this vision are a natural but ambitious continuation of the same concept.

The communication between MT and base station (i.e.; MT and Outside world) will be OFDM(orthogonal frequency division multiplexing ) which is a more efficient access technology than CDMA. Also 4G strongly visualizes communication ‘any time, any where and any mode’ which was in some respect a major limitation of 3G system. Increase in data rates of the user is also one of the major requirements of future generation of mobile communication system and it is expected to give 1000 times more bandwidth than what is available to a mobile user today.

All these high end services will be possible only with the implementation and physical realization of technical buzzwords like ‘IPv6’,’Mobile IP’, ‘Software Radio’ , ‘orthogonal frequency demodulation’, ‘Hyper LAN’, ‘Bluetooth’ and many more. All these do not become a reality over night and at free of cost but with billions of dollars of investment and years of research. It is expected that 4G services will be available only by 2010-2015, although it seems a long way from now but already research programs has started to actualise these concepts. Now the obvious question comes, who requires such high end services and also whether all these are going to be a reality or just a hype? With the increasing popularity of data and multimedia services , it is expected that these services will actually be on high demand in future. As we all know “Necessity is the mother of invention” but some times it works even other way round i.e.; technical innovations are used to create new/hidden necessities and some may call it a luxury, which is a topic of big debate and depends on the socio-economic condition of the people of a particular place. But in the past we have seen many technical innovations did not really took a commercial shape because of economic reasons and one classic example of this is the IRIDIUM project which was a technical success but a perhaps a commercial blunder.

Let’s try to see in brief, the scenario of mobile communication in India. In India we can see an expansion of GSM ( the 2nd generation system) system. Although the penetration in India is much less compare to U.S. and neighbouring China , it is surely picking up at a very fast pace. In India the mobile subscriber penetration is 0.6%( out of 1000 people, 6 has a mobile phone). In the state of Assam it is 0.1 % and in rest of NE it is as low as 0.038% . This kind of low penetration is due to socio-economic reasons but with the deregulation of Telecom sector , the penetration is expected to go high. Also we can expect 3G services will become a reality even in India, sooner or later. 4G services may look bit too futuristic at this point of time not only in India but else where.

To conclude we can say that , technical problems of the futuristic mobile communication systems may be solvable but economic and business justification for such a network is more complex. At the core, the future systems and concepts requires a fundamental change of orientation for wireless network operators- away from providing discrete services which they control and towards being a provider of access for users in parallel with other networks. By definition, they will required to support standard protocols for connectivity, billing, content and applications. At this moment this may not be the case every where. Despite of all these , the future generations of mobile systems will play a very important role in years to come. The road ahead for mobile and wireless industry may seems to be confusing and changing market conditions will be the final decider , many are keeping their finger crossed and hoping for the best. In such a rapidly evolving environment, it is difficult to predict when 4G or pervasive computing will finally become widespread realities but by the same token they seem unlikely to simply vanish . The importance of future mobile communication systems like 4G, inspires debates and visionary thinking which are both important steps for wireless industry to move forward. Whatever may the exact time frame and form of the future mobile communication systems, it is for sure that, these systems and innovative services, sooner or later, are going to make our life different, if not better.