Department of English Language and communication skills
S.V College of Engineering
Presented by: Guided by:
K.krishnateja M.D.Rafi sir (M.A,M.Phil,B.ed,Ph.d)
08bf1a1224 (Asst.prof. in English)
IT Vanaja Madam
Today, mobile communications play a central role in the voice/data network arena. With the deployment of mass scale 3G just around the corner, new directions are already being researched. In this paper we address about the 4TH G mobile communications.
The Fourth Generation (4G) Mobile Communications should not focus only on the data-rate increase and new air interface.4G Mobile should instead con-verge the advanced wireless mobile communications and high-speed wireless access systems into an Open Wireless Architecture (OWA) platform which becomes the core of this emerging next generation mobile technology. Based on this OWA model, 4G mobile will deliver the best business cases to the wireless and mobile industries,i.e.cdma2000/WLAN/GPRS 3-in-1 product, WCDMA/OFDM/WLAN 3-in-1 product, etc. Asia-Pacific is the most dynamic market of new generation mobile communications with over $100 Billion businesses in the next decade.
The 4G mobile technology -convergence of wireless mobile and wireless access, will definitely drive this growth. Any single-architecture wireless system, including 3G, HSDPA, WiMax, etc., is a transitional solution only, and will be replaced by open wireless architecture system very soon where various different wireless standards can be integrated and converged on this open platform.
The advent of 4G wireless systems has created many research opportunities. The expectations from 4G are high in terms of data rates, spectral efficiency, mobility and integration. Orthogonal Frequency Division Multiplexing (OFDM) is proving to be a possible multiple access technology to be used in 4G. But OFDM comes with its own challenges like high Peak to Average Ratio, linearity concerns and phase noise. This paper proposes a solution to reduce Peak to Average Ratio by clipping method. ATLAB as used to generate the OFDM signal to prove that clipping does reduce Peak to Average Ratio.
The first operational cellular communication system was deployed in the Norway in 1981 and was followed by similar systems in the US and UK. These first generation systems provided voice transmissions by using frequencies around 900 MHz and analogue modulation.
The second generation (2G) of the wireless mobile network was based on low-band digital data signaling. The most popular 2G wireless technology is known as Global Systems for Mobile Communications (GSM). The first GSM systems used a 25MHz frequency spectrum in the 900MHz band.
Planning for 3G started in the 1980s. Initial plans focused on multimedia applications such as videoconferencing for mobile phones. When it became clear that the real killer application was the Internet, 3G thinking had to evolve. As personal wireless handsets become more common than fixed telephones, it is
clear that personal wireless Internet access will follow and users will want broadband Internet access wherever they go.
What is 4G?
Fig 2 shows the concept of 4G cellular network. The future 4G infrastructure will consist of various networks using Internet Protocol (IP) as a common protocol. So the users will be in control as they can choose every application and environment. Accessing information any where, in time with seamless connections to a wide range of information, data, pictures, video and so on will be the benefits of 4G infrastructure.
One of the...