The Performance of a Dual Header Pulse Interval Modulation in the Presence of Artificial Light Interferences in an Indoor Optical Wireless Communications Channel with Wavelet Denoising

Abstract

Problem statement: Similar to other baseband modulation schemes, the performance of the Dual Header Pulse Interval Modulation (DH-PIM) is adversely affected by Artificial Light Interferences (ALI) in an indoor Optical Wireless Communications (OWC) channel. Approach: The Discrete Wavelet Transform (DWT) based denoising is studied for reducing the effect of the ALI. Computer simulation is carried out to demonstrate the effectiveness of the proposed system. The Baseline Wander (BLW) affects for a range of bit resolutions is also analyzed. Results: The normalized optical power requirement in the presence of ALI is high in the range of 9-15 dB depending upon the bit resolution. A significant reduction in the optical power penalty is observed with the DWT denoising scheme. Conclusion: The DWT based denoising scheme is effective in reducing the consequence of the ALI. The optical power penalty decreases with an increase in the data rate and the bit resolution, which is due to reduction of the DC values and low frequency spectrum.