Title :
Optical polar OFDM: On the effect of time-domain power allocation under power and dynamic-range constraints
Author :
Elgala, Hany ; Wilson, Sarah Kate ; Little, Thomas D. C.
Author_Institution :
Dept. of Electr. & Comput. Eng., Boston Univ., Boston, MA, USA
Abstract :
Polar OFDM (P-OFDM) is an OFDM format that can double the spectral efficiency of existing real-valued and unipolar optical OFDM intensity-modulation with direct detection (IM/DD) optical communication systems. P-OFDM modulates the amplitude and phase of a complex OFDM signal to allow a real unipolar signal. In this paper, we investigate the effect of power allocation to the phase and the amplitude components of P-OFDM time-domain signal on (1) the effective signal-to-noise ratio (SNR) at the receiver (2) the peak-to-average power ratio (PAPR) under transmit power constraint and (3) the induced clipping noise under optical-source´s dynamic-range and transmit power constraints. In addition to a 4 dB reduction in PAPR from ACO-OFDM, we demonstrate the improvement of throughput for P-OFDM over other optical OFDM methods when the signal power is limited.
Keywords :
OFDM modulation; amplitude modulation; constraint theory; intensity modulation; optical communication; optical modulation; phase modulation; time-domain analysis; ACO-OFDM; IM/DD optical communication system; P-OFDM; PAPR; SNR; amplitude modulation; clipping noise; dynamic-range constraint; intensity-modulation with direct detection; optical unipolar OFDM signal; peak-to-average power ratio; phase modulation; power constraint; signal-to-noise ratio; time-domain power allocation; Optical distortion; Optical modulation; Optical receivers; Peak to average power ratio; Signal to noise ratio; Intensity modulation; LED; Li-Fi; OFDM; Optical communications; Polar transmitter; VLC; Visible light communications; nonlinearity;
Conference_Titel :
Wireless Communications and Networking Conference (WCNC), 2015 IEEE
Conference_Location :
New Orleans, LA
DOI :
10.1109/WCNC.2015.7127440
