Mobile Phones



Communication is vital for effective transfer of information or idea. The effectiveness of communication depends on the means adopted to communicate. The choice is unlimited for a person today. The earlier known signs of communication were speech, sign language (including finger spelling into the palm of the deaf/blind), writing, Braille, body movements, and facial expression. This kind of communication was practiced among small groups. Communication on larger scale involves various forms. Technology has added impetus to the process. It has made the task of communication all the more easier.

1. Email - This is used to transferring files before a face-to-face meeting or updating on developments during the day. It is also a formal mode of communication. One can also use it as a means of non-urgent communication.

2. SMS - Short message service or SMS, is similar to email. It is difficult to ignore an SMS. It helps a person communicate by texting. It is non-intrusive too.

3. Phone call - It is used to speak or communicate with a person urgent. The best thing one can use it to call anyone from any place which resolves issues regarding urgency.

With the advent of mobile phones, the world has indeed been brought much closer. Initially, very few could afford it. The constant demand led to a massive production coupled with advancement in technology. It is no more confined to a class or section of people. Today, we can find people from the lowest strata using it; be it a cobbler or a day worker.

Mobile phones are available with additional features such as Bluetooth, email, camera, music, etc. It is no more confined to make a call or send text messages. It is meant for multiple purpose usage. They are available in various hues and colours too. The latest features are All in One Instant Messaging and Download All in One Instant Messengers. Many users have expressed their satisfaction about the services.

Instant messaging allows a user stay in touch round the clock with many people. A user can log in to accounts on multiple chat networks simultaneously. A user can consolidate Gchat, AIM, Yahoo Messenger, MSN Messenger, ICQ, and social network profiles in a single application. This enables a user chat with friends on MSN, talk to a friend on Google Talk, while sitting in a Yahoo chat room all at the same time. It is a marvel of technology indeed. It saves one from the hassle of downloading various applications and cut short the time being spent on each application. Technology has indeed undergone a sea change and made mobile phones a handy tool much on the lines of a PC.

Working Principle of Bluetooth Technology



Bluetooth was the brainchild of the SIG (Special Interest Group). This SIG included Intel, Toshiba, Nokia, IBM, Compaq, Dell, Motorola, HP, Lucent, and Samsung to name a few. They all came together to set up a short frequency wireless technology for transferring data.

Bluetooth is a communication protocol. It is a like a language that devices use to wirelessly communicate between each other. It is in fact based on a Master/Slave operation format. Pico net is a term used to describe a network formed by one device and all other devices detected in its range. In single coverage are around 10 Pico nets can co-exist. A master can connect to more than one slave simultaneously. In reality, the master keeps switching between slaves. Bluetooth links two Pico nets to form a larger network. This works over a short range and can be used to establish connections between PDAs, mobile phones, laptops, digital cameras, printers, scanner, and many other electronic gadgets.

Establishing a connection using Bluetooth is a complicated process. Initially, the device stays in a "Passive state", i.e. it is just in contact with the network, but not performing any activity. Next the connection establishment process begins with the inquiry process. "Inquiry" is a request sent by the master to all the devices found in its range. Whichever devices receive this inquiry send a response with their respective addresses. Now the master chooses one address and synchronises with its access point. This process known as the "Paging technique" involves alignment of its clock and frequency with that of the access point.

Next in line is the "Service Discovery" phase, wherein a link is established and the master device enters the access point using the Service Discovery Protocol. As a result of linking, a "Communication Channel" is to be created. Sometimes the access point may include a security mechanism and you may need to know the encryption key or in common terms the PIN. Once the PIN is sent and received and confirmed a communication is established. Finally the master and slave can use the communication channel to transfer data and information.

Thus Bluetooth is neither a broadband nor a long distance networking technique. It is a Personal Area Networking technology that can be used in a number of important applications. First of all, Bluetooth technology uses the same frequency range as the Wi-Fi system. It only requires a careful coordination of the various frequencies with the perfect transmit and receive timings between various devices. Finally, the enhanced version of Bluetooth is expected to use Ultra-Wide Band frequencies that contributes increased data rate and improved signal strength.