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Wireless communication

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Unlike other previous forms of communication, wireless communication networks have increasingly gained popularity especially with the recent mode like 3G and 4G which have continuously improved data transfer and communication efficiency. Recent advances in technology have led to efficient satisfaction of the needs of consumers while ensuring that life is easier. The second generation GSM and its evolutional stages of GPRS and EDGE and third generation UMTS are discussed in detail to pave way in understanding the 4G technology. Wireless communication: 1G-4G cellular communication systems 1.0. Introduction Cellular mobile telephone systems development and deployment was triggered by the operational limitations of standard mobile telephone systems (Brand and Aghavami, 1). These limitations include limited capacity for service, inefficient utilization of spectrum and poor service performance. The communication of mobile phone occurs through a temporary distinct radio channel in order to communicate to the cell site. The cell site is contains several channels and each mobile talks to it through only one of the channels. The channels are characterized by a pair of frequencies which are used during the communication. The forward link transmits from the cell site to the users while the reverse link receives calls from users. The radio signal transmitted in early mobiles dissipated with distance and mobiles had to stay close to the base station in order to secure effective communications. According to Brand and Aghvami (1), moving mobile users were not sufficiently offered with an effective means of communication. Mobile radio service has its operations in a closed network with no access to the telephone system unlike the mobile telephone service that allowed interconnection to the telephone network. Traditionally, the mobile service structure included a single powerful transmitter that was located at a high spot to broadcast signals within a radius of up to about 50 km and the mobile telephones were attached to the transmitter (Brand and Aghvami, 2). Conversely, the introduction of cellular telephone system architecture involves placing numerous low-power transmitters within the entire coverage area and each covers a small area called the cell and using varying channels or conversions. The cellular telephone system allows a user to travel while making a phone call with no interruptions since they can use more than one base station. The application of the cellular concept in mobile telephone systems overcame interference problems and improved the efficiency of communication since the cells size was equivalent to the density and demand of subscribers in a particular area and was flexible to accommodate growing population’s demand and user density. Interference is overcame since a cluster can be reused in other cells while conversations can be handed off from one cell to the other and phone services maintained constantly as one moves between cells through handoff (Brand and Aghvami, 2). Cellular phone systems is characterized by four generations which are first generation or 1G, second generation or 2G, third generation or 3G and fourth generation or 4G. This paper explores cellular mobile system generations in terms of their capabilities, date of introduction, and comparison of inherent features. 2.0. First generation or 1G cellular phone systems The 1G cellular phone systems are characterized by the use of analog frequency modulation to facilitate the transmission of speech, frequency shift keying or FSK for signaling while FDMA or frequency Division Multiple Access for the sharing of assigned spectrum (Patil, Karhe and Aher, 614). The most