Compressive sensing-based channel bandwidth improvement in optical wireless orthogonal frequency division...

Area of Science:

• Optical Wireless Communication
• Signal Processing
• Data Transmission

Background:

• Orthogonal frequency division multiplexing (OFDM) links using light-emitting diodes (LEDs) face limitations in channel bandwidth.
• Visible light communication (VLC) systems require efficient data transmission methods to increase data rates.

Purpose of the Study:

• To propose and evaluate a novel technique that compensates for bandwidth limitations in LED-based VLC-OFDM links.
• To enhance the data rate of VLC systems by utilizing compressive sensing (CS) principles.

Main Methods:

• Implementation of an adaptive sampling and inverse discrete cosine transform to convert OFDM signals into sparse waveforms.
• Application of compressive sensing (CS) to reconstruct sparse signals sampled below the Nyquist/Shannon limit.
• Integration of CS technique into a VLC-OFDM link architecture.

Main Results:

• The proposed CS-based VLC-OFDM link achieved a 1.7 times greater data rate compared to conventional links, increasing from 30.72 Mb/s to 51.2 Mb/s.
• At a compression ratio of 40%, the error vector magnitude (EVM) for quadrature phase shift keying (QPSK) symbols was 31%, which is within the forward error correction (FEC) limit of 32%.

Conclusions:

• The proposed CS technique effectively increases the data rate of LED-based VLC-OFDM systems by efficiently processing signals and removing redundancy.
• This method offers a viable solution for overcoming bandwidth constraints and improving the performance of visible light communication.