Amin aliabadi - industrial of space

Due to the limitations of second generation mobile telecommunications system (GSM) in the message available bit rate of user, And limited mobile services as voice calls (The signal sent to the SMS service) And the demand for services such as Internet (Web Browsing), TV, send picture and video data as and etc… Operators at European, Japanese and American (in a single system called ۳GPP) to send a data packet switch or IP۳ (nor CS۴) will attract. In this paper, given that growth in third generation mobile phones (UMTS۹۹ techniques under R۹۹ = WCDMA) has evolved , And also in the other versions of five papers (HSDPA), six (HSUPA & MBMS), seven (HSPA +) have been investigated. Many scientists believe that a review eight Version, four-generation mobile l (LTE) to increase the bit rate available to users of cellular mobile networks (under the same bandwidth), Increasing the bit rate available to users in the DL with the introduction of HSDPA in version ۵ (۲۰۰۵), in the UL introduced the HSUPA version ۶ (۲۰۰۷) and the release of seven and eight, with the introduction of HSPA + and LTE in both the UL and DL (۲۰۰۹) has begun, This evolution is likely to be completed in ۲۰۲۰. Few countries in the third generation now outdated and LTE is being used as experimental. Defects disappear in the course of ۲۰۱۴ will reach a more favorable situation. Proposal and agreement for the LTE radio technology that was used. For DL OFDMA and SC-FDMA is in the UL. In this article an overview of the techniques being considered for LTE Release ۱۰ (aka LTE Advanced) is discussed. This includes bandwidth extension via carrier aggregation to support deployment bandwidths up to ۱۰۰ MHz , downlink spatial multiplexing including single-cell multi-user multiple-input multiple-output transmission and coordinated multi point transmission, uplink spatial multiplexing including extension to four-layer MIMO, and heterogeneous networks with emphasis on Type ۱ and Type ۲ release.

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