Spectral Analysis of Convolutional Coded DPIM for Indoor Optical Wireless Communications

Power Spectral Density (PSD) of the Convolutional Coded Digital Pulse Interval Modulation (CC-DPIM) is derived analytically based on the stationarization of Variable-Length Word Sequence (VLWS). To verify the theoretical model developed, CC-DPIM is simulated in Matlab and its spectrum is compared with the predicted results showing a close match. As in DPIM scheme, CCDPIM spectrum also contains a distinct slot (clock) component which can be recovered at the receiver for both slot and symbol synchronization.