الفهرس 
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Abstract
We have seen a tremendous amount of growth m past few decades in wireless communication industry. It started with first generation (l G) system which was basically deployed for voice communications and very limited mobility. After this it was the second generation (2G) which provided better capacity and better voice quality compared to 1 G system. 2G system mainly consisted of GSM (global system for mobile communications) and CDMA (code division multiple access) which were designed with voice service in the mind. Data traffics were supported in 2G system but the user throughput was very less and later both technologies felt a need to upgrade their system to support higher data throughput along with support for voice. This gave result to a new revolution, which we sometime refer to as third generation or 3G systems. 3GPP’s 3G standard was called UMTS (wideband CDMA using 5MHz bandwidth) and 3GPP2’s standard was named cdma2000. However, with the first release of 3G, the requirement for high speed data was not completely fulfilled. Today is the world where we need a telecommunication system which has to fulfill the requirements for voice, video, telephony, interactive media, streaming media, and some services with loss less requirements such as file transfer and email. UMTS networks have already been upgraded with High Speed Packet Access (HSDPA) and currently it is getting evolved to HSPA+ which will have multiple antennas deployment, new modulation scheme and some improvements in system protocols. We can expect 10 more years for further improvements with HSP A + and to ensure competitiveness of UMTS new concepts are being investigated in L TE to fulfill these demands. With LTE, we will have new access schemes like OFDMA in down link, SC-FDMA in uplink. Also, LTE will have new concept called multiple input and multiple output (MIMO) with 2 receive antenna and 1 transmit antenna at UE which will support 100 Mbps DL data rate and 50 Mbps UL data throughput. In DL spectral efficiency is about 3 times and sometimes 4 times better and in UL it’s 2 to 3 times better.