Digital Signal Processing

Techniques De Réduction Du PAPR (PAPR Reduction Techniques)

Authors: Wendyida Kabore Kabore
Comments: 73 Pages. [Corrections made by viXra Admin to conform with the requirements on the Submission Form]

Power amplification efficiency enhancement is a critical issue for wireless communication applications. The amplification of signals that have a high dynamic range consumes a lot of energy. Amplifying signals with a constant envelope is a possible solution to get a maximum performance of the amplifier. However, the signals that are currently available in several systems, are multi-carrier signals which are very attractive but have a high PAPR in principle. During this internship, we studied a multi-carrier waveform (to enjoy all the benefits inherent in it) with a low PAPR. This is about to use PAPR reduction techniques like "adding signal" methods, coupled with a new definition of the multicarrier signal. The clipping for example, has been modeled as an adding signal technique, but the addition of the clipping signal occurs on certain free subcarriers that are not used to transmit data. Not all the clipping signal frequencies are used. The major problem is that the subcarriers on which the clipping signal can be added are reduced in number. So to add the clipping signal more efficiently we need to have more frequency space. The key idea here is to perform the duobinary coding in each of the OFDM subcarriers. The duobinary coding reduces the spectral occupancy by half. Thus, we can use the vacant spectrum to add the clipping signal orthogonaly to the data signal. Then comes the study of the performances of this new waveform in terms of gain in PAPR, complexity (receiving process) and ACPR. This study confirm the efficiency of the proposed technique.
Category: Digital Signal Processing