| dc.description.abstract | In recent years, with the rapid development of wireless multimedia, making wireless communication systems must transfer large amount of data in a limited bandwidth for effective use that bandwidth resources, next-generation wireless communication standard commonly used in orthogonal frequency division multiplexing (OFDM) modulation technology based.
LTE (Long Term Evolution) system was developed by 3GPP (3rd Generation Partnership Project) proposed by the fourth generation of mobile communication systems. LTE downlink using OFDMA (Orthogonal Frequency Division Multiple Access) system, which is based on OFDM system evolved, the uplink is using single carrier frequency division multiplexing access (SC-FDMA) systems. SC-FDMA is an evolution of the OFDMA, also known as linear pre-coding OFDMA technology. LTE uplink(UL) and downlink(DL) technology is very similar, but the SC-FDMA is characterized in that the output of a single carrier frequency transmission signal. Since the SC-FDMA is the modulation symbols for each subcarrier at the same time to do linear combination, so each sub-carrier signal of measure vector is respective. Make SC-FDMA system than OFDMA system with lower peak/average power ratio (Peak-to-Average Power Ratio, PAPR). In this way, it is possible to improve the power transmission efficiency of the mobile terminal, saving battery consumption and reducing the cost of the terminal. However, for the downlink, the linear power amplifier (LPA) to show the importance for OFDM system. | en_US |