Article

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.

0 Followers
 · 
87 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An analog photonic link with the compensation of the dispersion-induced power fading is proposed and demonstrated based on phase modulation to intensity modulation conversion in a Sagnac loop. Due to the velocity mismatch of the modulator, only the incident light wave along the clockwise direction is effectively modulated by the radio frequency signals, while the counterclockwise light wave is not modulated. After combining the two light waves in a polarizer, an intensity modulated optical signal is generated, which can be directly detected. In addition, the phase difference between the two light waves can be adjusted through the polarization controller before the polarizer. This feature is used to shift the frequency response of a dispersive link to compensate the dispersion-induced power fading at any working frequency. Experimental results show that the power fading after transmission over both 25 and 50 km lengths of fiber in a conventional intensity modulated link can be successfully compensated in the proposed link, and thus, a high and constant link gain over a large frequency range is achieved. The spur-free dynamic ranges of the link before and after fiber transmission are also measured.
    Journal of Lightwave Technology 01/2015; 33(13):1-1. DOI:10.1109/JLT.2015.2420658 · 2.86 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This letter presents a chromatic dispersion (CD) compensation scheme using parallel electro-optic phase and intensity modulators suitable for long-reach radio-over-fiber links. By properly adjusting the optical power and the time delay between the two modulated signals, the power fading aroused by the CD is adequately compensated over a wide operating bandwidth of 0–18 GHz over a 34-km single-mode fiber (SMF). Compared with a double sideband (DSB) modulated link, an enhancement of up to 31 ${\rm dB}{\mmb\cdot}{\rm Hz}^{2/3}$ in the spur-free dynamic range for a 9.5-GHz signal is obtained. Furthermore, a bit-error rate of $10^{-10}$ is obtained when a 9.5-GHz carrier loading 2-Gb/s pseudorandom bit sequence is transmitted over the dispersive link, which is not achievable for the DSB modulated link.
    IEEE Photonics Technology Letters 07/2012; 24(14):1173-1175. DOI:10.1109/LPT.2012.2192422 · 2.18 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents a continuously tunable microwave photonic notch filter with a complex coefficient. The complex coefficient is generated using a radio-frequency (RF) phase shifter that consists of a dual-parallel Mach-Zehnder modulator (DPMZM) and a tunable optical bandpass filter (TBPF). By simply controlling the bias voltage of the DPMZM, the frequency response of the filter can be continuously tuned over a full free spectral range (FSR) without changing the shape of the frequency response.
    IEEE Photonics Journal 06/2011; 3(3):462-467. DOI:10.1109/JPHOT.2011.2149509 · 2.33 Impact Factor