Title :
AM/OFDM versus AM/QAM for mixed analog/digital subcarrier multiplexed lightwave transmission
Author_Institution :
Panasonic Technol. Inc., Princeton, NJ, USA
Abstract :
Hybrid multichannel AM/QAM subcarrier multiplexed (SCM) lightwave systems are attractive for mixed analog/digital video-data transport over hybrid fiber/coax (HFC) networks. In this paper we show that significant bit-error-rate (BER) improvements can be obtained using AM/OFDM (orthogonal frequency division multiplexing) vis-a-vis AM/QAM, when corrupted by both clipping-impulse and Gaussian noise. It is shown that the clipping effect on the BER of an OFDM signal can be negligible for a large range of laser optical modulation depths, and therefore, virtually no limit is imposed on the channel capacity. It is further shown that OFDM introduces little effect on the analog AM channels, as opposed to use of QAM systems.
Keywords :
amplitude modulation; frequency division multiplexing; optical fibre networks; optical modulation; optical noise; quadrature amplitude modulation; subcarrier multiplexing; AM/OFDM; AM/QAM; BER; Gaussian noise; HFC network; clipping-impulse noise; hybrid multichannel system; laser optical modulation depth; mixed analog/digital video-data; subcarrier multiplexed lightwave transmission; Bit error rate; Coaxial components; Degradation; Gaussian noise; Hybrid fiber coaxial cables; Interference; Noise level; OFDM; Quadrature amplitude modulation; Signal to noise ratio;
Conference_Titel :
Advanced Applications of Lasers in Materials Processing/Broadband Optical Networks/Smart Pixels/Optical MEMs and Their Applications. IEEE/LEOS 1996 Summer Topical Meetings:
Conference_Location :
Keystone, CO, USA
Print_ISBN :
0-7803-3175-3
DOI :
10.1109/LEOSST.1996.540703