Compensation of dispersion-induced power fading for highly linear radio-over-fiber link using carrier phase-shifted double sideband modulation

Tsinghua National Laboratory for Information Science and Technology, Department of Electronic Engineering, Tsinghua University, China.
Optics Letters (Impact Factor: 3.18). 02/2011; 36(4):546-8. DOI: 10.1364/OL.36.000546
Source: PubMed

ABSTRACT A carrier phase-shifted (CPS) double sideband (DSB) modulation technique in radio-over-fiber (RoF) system is proposed and experimentally demonstrated. By tuning the biases in a single-drive dual parallel Mach-Zehnder modulator (SD-DPMZM), the optical carrier in the DSB spectrum acquires additional phase shift. The transmittance response of a dispersive RoF link is thus being controlled and shifted in the frequency domain. Experiments successfully turned the maximum transmission frequency to 10 GHz and 15 GHz for both 25 and 39 km fiber links. This is also a highly linear scheme, of which a spurious-free dynamic range (SFDR) of 111.3 dB·Hz2/3 is experimentally obtained.

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