All-optical microwave bandpass filters implemented in a radio-over-fiber link

An all-optical microwave bandpass filter implemented in a radio-over-fiber (RoF) link is proposed and demonstrated. The filter consists of an optical phase modulator, a length of high birefringence (Hi-Bi) fiber, a 25-km singlemode fiber and a narrow linewidth laser source. Different time delays are achieved when the two orthogonal polarization modes are traveling along the Hi-Bi fiber. The baseband resonance is eliminated by use of the optical phase modulator in combination with the 25-km single-mode fiber serving as a dispersive device. The proposed filter is immune to optical interference because of the orthogonality of the two polarization modes. A two-tap all-optical microwave bandpass filter with a null-to-null bandwidth of 8.7 GHz and a notch rejection level greater than 30 dB implemented in the 25-km RoF link is demonstrated.

[1]  R. Minasian,et al.  Novel all-optical RF notch filters with equivalent negative tap response , 2004, IEEE Photonics Technology Letters.

[2]  I. Bennion,et al.  Optical fibre delay line filter free of limitation imposed by optical coherence , 1999 .

[3]  J. Chen,et al.  A novel digitally tunable microwave-photonic notch filter using differential group-delay module , 2003, IEEE Photonics Technology Letters.

[4]  B. Jalali,et al.  All-optical RF filter using amplitude inversion in a semiconductor optical amplifier , 1997 .

[5]  J. Capmany,et al.  Experimental demonstration of fibre-optic delay line filters with negative coefficients , 1995 .

[6]  A novel all-fiber bipolar transversal filter with complementary outputs , 2002, 2002 International Topical Meeting on Microwave Photonics.

[7]  I. Bennion,et al.  A novel tunable all-optical incoherent negative-tap fiber-optic transversal filter based on a DFB laser diode and fiber Bragg gratings , 2000, IEEE Photonics Technology Letters.

[8]  Kam Tai Chan,et al.  Tunable all-optical incoherent bipolar delay-line filter using injection-locked Fabry-Perot laser and fibre Bragg gratings , 2000 .

[9]  S. Xie,et al.  Sampled Bragg grating with desired response in one channel by use of a reconstruction algorithm and equivalent chirp. , 2004, Optics letters.

[10]  R.A. Minasian,et al.  Photonic notch filter without optical coherence limitations , 2004, Journal of Lightwave Technology.

[11]  B. Bakhshi,et al.  Direct generation of subpicosecond chirp-free pulses at 10 GHz from a nonpolarization maintaining actively mode-locked fiber ring laser , 2000, IEEE Photonics Technology Letters.

[12]  J. Capmany,et al.  Microwave photonic filters with negative coefficients based on phase inversion in an electro-optic modulator. , 2003, Optics letters.

[13]  D Pastor,et al.  Tunable all-optical negative multitap microwave filters based on uniform fiber Bragg gratings. , 2003, Optics letters.

[14]  Fei Zeng,et al.  All-optical bandpass microwave filter based on an electro-optic phase modulator. , 2004, Optics express.