The effect of wavelet transform on OFDM system in modern cellular networks

Abstract

Wavelet transform has many advantages that make it suitable and efficient approach to replace Fast Fourier Transform (FFT) in conventional Orthogonal Frequency Division Multiplexing (OFDM) systems. Wavelet transform is employed in modern cellular networks to remove the use of cyclic prefix, which leads to decreasing the bandwidth losses and the power of transmission. Wavelet based OFDM system is designed in order to overcome the drawbacks of OFDM system so that the proposed system is good candidate for next generation wireless communications.

Distributed differential beamforming and power allocation for cooperative communication networks

“…However, with the need for higher data rate and better performance in the current wireless communication systems, investigating new channel coding techniques is essential for such needs. Many methods have been proposed in order to increase the data rate such as massive multiple-input multiple-output (MIMO) techniques [17][18][19][20][21][22][23][24][25][26][27][28], carrier aggregation and different encoding techniques. However, these techniques increase the complexity of the communication systems.…”

“…Some techniques such as distributed beamforming assumes a perfect CSI at all nodes, which is considered unrealistic [17,18]. Techniques like distributed space-time coding (DSTC) consider a perfect or semi perfect CSI at the receiver [4][5][6][7][8] while other techniques such as time reversal (TR) consider a perfect CSI at transmitter side [27]. The need for CSI leads to a significant increase in the system complexity.…”