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HISTORY OF CELLULAR TELEPHONY1947 Bell Laboratories introduced the idea of cellular communications with the police car technology. 1947 The basic concept of cellular phones began, when researchers looked at crude mobile (car) phones and realized that by using small cells (range of service area) with frequency reuse they could increase the traffic capacity of mobile phones substantially. However at that time, the technology to do so was nonexistent. 1947 AT&T proposed that the FCC allocate a large number of radio-spectrum frequencies so that widespread mobile telephone service would become feasible. 1947 The FCC decided to limit the amount of frequencies available, the limits made only twenty-three phone conversations possible simultaneously in the same service area. 1968 AT&T and Bell Labs proposed a cellular system to the FCC of many small, low-powered, broadcast towers, each covering a CELL a few miles in radius and collectively covering a larger area. Each tower would use only a few of the total frequencies allocated to the system. As the phones traveled across the area, calls would be passed from tower to tower. 1968 The FCC reconsidered its position by stating "if the technology to build a better mobile service works, we will increase the frequencies allocation, freeing the airwaves for more mobile phones." 1973 (April) The first call on a portable cell phone is made by Dr Martin Cooper, a former general manager for the systems division at Motorola, who is also considered the inventor of the first modern portable handset. 1977 AT&T and Bell Labs had constructed a prototype cellular system. A year later, public trials of the new system were started in Chicago with over 2000 trial customers. 1979 The first commercial cellular telephone system began operation in Tokyo. 1980 Analog cellular telephone systems were experiencing rapid growth in Europe, particularly in Scandinavia, United Kingdom, France and Germany. Each country developed its own system, which was incompatible with everyone else in equipment and operation 1981 Motorola and American Radio telephone started a second U.S. cellular radio-telephone system test in the Washington/Baltimore area. 1982 FCC authorizes commercial cellular service for the USA. 1982 The Conference of European Posts and Telegraphs (CEPT) formed a study group called the Group Special Mobile (GSM) to study and develop a pan-European public land mobile system. The proposed system had to meet certain criteria: • Good subjective speech quality • Low terminal and service cost • Support for international roaming • Ability to support handheld terminals • Support for range of new services and facilities • Spectral efficiency • ISDN compatibility 1983 The first American commercial analog cellular service or AMPS (Advanced Mobile Phone Service) was made available in Chicago by Ameritech. 1987 Cellular telephone subscribers exceeded one million and the airways were crowded. 1989 GSM responsibility was transferred to the European Telecommunication Standards Institute (ETSI), 1990 Phase I of the GSM specifications were published. 1991 Commercial launch of cellular service based on GSM standard in Finland. 1992 Telecommunication sector in India liberalized to bridge the gap through government spending & to provide additional resources for the nation telecom target. Private sector allowed participating 1993 The telecom industry gets an annual foreign investment Rs 20.6 million 1994 License for providing cellular mobile services granted by the government of India for the Metropolitan cites of Delhi, Mumbai, Kolkata & Chennai. Cellular mobile service to be duopoly (i.e. not more than two cellular mobile operators could be licensed in each telecom circle), under a fixed license fee regime for 10 years. 1995 19 more telecom circles get mobile licenses 1995 (August) Kolkata became the first metro to have a cellular network 1997 Telecom Regulatory Authority of India is set up 1998 Annual foreign investment in telecom stands at Rs 17,756.4 million. 1999 FDI inflow into telecom sector falls by almost 90% to Rs. 2126.7 million 1999 Tariff rebalancing exercise gets initiated 1999 (March) National Telecom Policy is announced. 2000 (June) FDI inflow drops further down to Rs 918 million coming 2000 (January) Amendment of TRAI Act. FAQs (Frequently asked questions)?Q.What type of handset work in India? A. The handset should be GSM 900 / 1800 compatible. Q. What parameters should be kept in mind while purchasing a handset? A. 1. Your budget 2. Battery Type 3. Stand by and Talk Time 4. Size, Weight and aesthetics 5. Compatibility for SMS, WAP or GPRS etc. if required 6. Availability of features like vibra alert or port for connectivity with laptop if required 7. Other features like last calls record, phone memory, clock, alarm, calculator, games etc. should be checked before purchase according to your requirement. Some features are network dependent also. 8. If looking for camera phone, go in for the ones with larger display, better resolution, more memory, flash and zoom. 9. Fond of music then check for FM Radio and MP3 player. Phone memory, MMC card support and strong battery are important considerations for heavier audio or video files. Q. What to choose GSM or CDMA? How to choose a Service provider? A. GSM and CDMA are the two main competing network technologies deployed by cellular service providers world over. Understanding the pros and cons of both the technologies will help you make right decision according to your requirement. GSM vs CDMA GSM and CDMA are the two main competing network technologies deployed by cellular service providers world over. Understanding the pros and cons of both the technologies will help you make right decision according to your requirement. GSM (Global System for Mobile Communications) originated in Europe in 1990. The GSM Association is an international organization founded in 1987, dedicated to developing, providing and overseeing the worldwide wireless standard of GSM. While CDMA (Code Division Multiple Access) is a proprietary standard designed by Qualcomm Inc in United States and has been the dominant network standard for North America and parts of Asia. It became an international standard in 1995. However now, GSM networks have penetrated the United States and the CDMA networks have spread in other parts of the world. People of both the camps claim that their architecture is superior to the other. The Technology: Mobile personal communication systems use microwave frequencies above 800 MHz for transmission and reception. All service providers operate in some pre allocated frequency bands according to international standards. For operating in these microwave frequencies there are following access methods: • FDMA (Frequency Division Multiple Access) - FDMA puts each call on a separate frequency. • TDMA (Time Division Multiple Access) - TDMA assigns each call a certain portion of time on a designated frequency. • CDMA (Code Division Multiple Access) - CDMA gives a unique code to each call and spreads it over available frequencies. GSM is a global standard based on TDMA. It is very popular in entire Europe, Middle East and Asia while CDMA is the dominant technology in United States and some parts of Asia. But how does it effects the ultimate consumer? I hope following considerations may be helpful. Consider the following while selecting a Service Provider: 1. First of all you must check which Service Providers are providing services in the areas where you will be using your phone. 2. If you want National or International Roaming then also check whether the Service Provider you have chosen facilitates roaming in the regions or countries where you visit frequently. 3. Cost of owning a handset 4. Cost of having a connection 5. Fixed monthly expenses 6. Usage charges. 7. Also it is helpful to check with the people using mobile in your area for the quality of service. Q. What are Post-Paid and Pre-Paid Sim Cards. Which Sim card should be purchased to keep the cost minimum? A. In case of Post-Paid Sim Card you get monthly bill according to your usage while in case of Pre-Paid you use a fixed amount which is included in the cost initially. Pre-Paid cards can be recharged using recharge coupons available in different denominations. To keep the cost in control buy a Pre-Paid Card. You get STD & ISD also without any security deposit. Post Paid cards offer various price plans and is better option if the usage is high. Q. What are the types of batteries available and which is the best? A. Nickel Metal Hydride, Lithium Ion and Nickel Cadmium. Lithium Ion batteries are considered better. Q. What is the correct procedure of charging a battery? A new battery should be charged for 10-12 hrs for the first 3-4 times this makes the battery seasoned for better results and longer life. Battery should be charged only when it gets fully discharged since all the batteries are designed for certain charge cycles which should not be wasted by semi charging. Also half charged battery when put for charge, start showing false charging quickly even when the battery has not charged fully. When such batteries are put to use, they get discharged also very fast. After the initial charging as above one should follow the normal charging procedure as displayed on the handset or given in the handset manual. Q. Explain Roaming card advantage and billing method? A. a. Advantage-Number remains the same wherever you travel. b. Billing - Assume you have taken Roaming facility from Delhi and you travel to Mumbai. Then the charges will be as mentioned below: - 1. Calls you make in Mumbai is Air Time charges only. 2. Call received from anywhere you pay STD charges Delhi to Mumbai + Air Time. 3. If somebody calls you from Mumbai he pays Mumbai to Delhi STD charges and you pay Delhi to Mumbai STD charges + Air Time. Q. What is PIN number and what to do if SIM gets blocked? As soon as you insert a SIM Card in any Handset it asks for PIN (Personal Identification Number) which is a password that is known to the authorized user only. The PIN code can be set to protect your SIM card from unauthorized use. To prevent continuous attempts to GUESS the PIN number the SIM card automatically gets locked-up after three consecutive wrong entries. If the SIM card is locked-up, the "Blocked" message will appear and an unlocking code will be needed. Further repeat wrong entries of PIN may lead to damage of card. The blocked SIM can be then opened through PUK number (PIN Unlocking code) which can be obtained from your service provider after establishing your identity. The PUK is an 8 digit code available with your cellular service provider. Also one should remember that 10 times successive wrong entries of PUK number may damage the SIM card forever. Q. What are the functions of a SIM card? A. 1. SIM Card carries the users identity for accessing the network and receiving calls. 2. All calls are charged against their SIM card account. 3. It is also equipped with a memory to store telephone numbers along with names. 4. It also enables you to send and receive short messages (SMS). Q. How to protect your SIM card from getting damaged? A. 1. Insert and remove SIM card carefully and donot do this frequently. 2. Do not scratch, bend or twist the SIM and never write on it. 3. Keep your SIM away from extensive heat. 4. Keep cleaning your SIM cards once in three months with soft cotton to remove any possible dust particles. 5. Keep the unused SIM wrapped in clean, non sticky paper at a safe place. Q. What is an IMEI number of the mobile handset and how can we get it? A. The IMEI number is a 15 digit number unique to a mobile handset which can help in tracking your mobile phone if it is lost. Just key in *#06# on your cellular phone and it will display its IMEI number. Note it down safely. |
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