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In this work, we propose Full Volterra and Sparse Volterra channels equalization algorithms for downlink LTE system. For estimation purpose, the LTE standard provides known data as pilot symbols and exploits them through a coherent detection to improve system performance. The references symbols location is similar to diamond pattern through time and frequency domain. Our goal is to show how to use the Full Volterra and Sparse Volterra equalizers over frequency domain in order to mitigate linear and nonlinear effects introduced by power amplifier and multipath channel. Downlink LTE Performances System in term of BLER, EVM (%) and Throughput versus SNR are presented and discussed. Then we compare our results with basic RLS equalizer curves. Moreover, it is shown that the Full Volterra and Sparse Volterra models can significantly reduce interferences and nonlinear effects and consequently improve the performances of LTE Downlink System.

Long term evolution is standardized by the 3rd Generation Partnership Project to provide a high data rate up to 100 and 50 Mbps for downlink and uplink transmission respectively and can operate in different bandwidths ranging from 1.4 up to 20 MHz. Downlink LTE system is based on the OFDMA technique and uses several enhanced techniques in order to increase the spectral efficiency and aggregate the cell throughput. The incorporated scheduling mechanisms can significantly contribute to this goal. Scheduling mechanism is the process of allocated the resources (time and frequency) to users transmitting different flows in same time. In this paper, we propose a novel scheduling algorithm for downlink transmission in LTE system. The performances of the newly scheduler are simulated and compare to the performances of three basic scheduler such as Round Robin, Proportional Fair and Max Rate.

We propose a Wiener-Hammerstein (W-H) channel estimation algorithm for Long-Term Evolution (LTE) systems. The LTE standard provides known data as pilot symbols and exploits them through coherent detection to improve system performance. These drivers are placed in a hybrid way to cover up both time and frequency domain. Our aim is to adapt the W-H equalizer (W-H/E) to LTE standard for compensation of both linear and nonlinear effects induced by power amplifiers and multipath channels. We evaluate the performance of the W-H/E for a Downlink LTE system in terms of BLER, EVM and Throughput versus SNR. Afterwards, we compare the results with a traditional Least-Mean Square (LMS) equalizer. It is shown that W-H/E can significantly reduce both linear and nonlinear distortions compared to LMS and improve LTE Downlink system performance.

In this paper, the principles of coherent optical Fast-OFDM and the modem design with the employment of a Wiener-Hammerstein equalizer (W-H/E) are described. Afterwards, we test 16QAM Fast-OFDM with W-H/E for up to 3500 km of transmission. Finally, we compare coherent optical Fast-OFDM with conventional CO-OFDM using W-H/E.

In this work, we propose a Full Volterra channel equalization for downlink LTE system. For estimation purpose, the LTE standard provides known data as pilots symbols and exploits them through a coherent detection to improve system performance. These drivers are placed in a hybrid way to cover up both time and frequency domain. Our aim is to precise how to adapt the Full Volterra technique to the LTE standard in order to compensate linear and nonlinear effects introduced by power amplifier and multipath channel. We present the comportment of Full Volterra equalizer in term of BLER, EVM (%) and Throughput versus SNR. Then we compare our results with basic RLSequalizercurves. Moreover, it is shown that the Full Volterra model can significantly reduce interferences and nonlinear effects and consequently improves the performances of LTE Downlink System.