Source Code Implementation of Clipping Method for PAPR Reduction in OFDM Systems

In OFDM (Orthogonal Frequency Division Multiplexing) systems, Peak-to-Average Power Ratio (PAPR) is a crucial performance parameter. Various clipping techniques have been proposed to reduce PAPR, with source code-based clipping method being an effective approach. This paper demonstrates the implementation of source code-based clipping method to reduce PAPR in OFDM systems and presents the results graphically.

The implementation is carried out using MATLAB software. Initially, we develop MATLAB code to generate standard OFDM signals using IFFT (Inverse Fast Fourier Transform) operations. The core algorithm involves creating complex subcarriers with QAM modulation, applying IFFT transformation, and adding cyclic prefix. Subsequently, we integrate the clipping algorithm which implements amplitude limitation by defining a clipping threshold and applying nonlinear compression to signal peaks exceeding this threshold. The clipping function processes each OFDM symbol by comparing instantaneous power levels against the predetermined threshold and scaling down excessive peaks while maintaining phase information.

Finally, we utilize MATLAB's built-in plotting tools to generate comparative graphs showing PAPR performance before and after clipping. The graphical representation includes CCDF (Complementary Cumulative Distribution Function) curves that statistically demonstrate PAPR reduction effectiveness. Through this research, we conclude that the source code-based clipping method significantly reduces PAPR in OFDM systems and enhances overall system performance. However, we also observe that clipping introduces some distortion effects on Bit Error Rate (BER), which requires comprehensive consideration in practical applications where trade-offs between PAPR reduction and signal fidelity must be balanced.