All-Fiber Chirped Microwave Pulses Generation Based on Spectral Shaping and Wavelength-to-Time Conversion

An approach to generating chirped microwave pulse based on optical spectral shaping and nonlinear chromatic-dispersion-induced wavelength-to-time mapping using all-fiber components is proposed and demonstrated. In the proposed approach, the spectrum of a femtosecond pulse is shaped by a two-tap Sagnac-loop filter that has a sinusoidal spectrum response. The spectrum shaped pulse is then sent to a dispersive element that has first- and second-order chromatic dispersions. Thanks to the nonlinear wavelength-to-time mapping of the dispersive element, a temporal pulse that has a central frequency in the microwave band with a large chirp is generated, which provides the potential for applications in high-speed communications and radar systems. Numerical and proof-of-concept experimental results are presented.

[1]  M. Amemiya,et al.  Pulse broadening due to higher order dispersion and its transmission limit , 2002 .

[2]  T A Birks,et al.  Group-velocity dispersion in photonic crystal fibers. , 1998, Optics letters.

[3]  J. Arriaga,et al.  Anomalous dispersion in photonic crystal fiber , 2000, IEEE Photonics Technology Letters.

[4]  A. Zeitouny,et al.  Optical generation of linearly chirped microwave pulses using fiber Bragg gratings , 2005, IEEE Photonics Technology Letters.

[5]  W. Zhao,et al.  Femtosecond pulse propagation in optical fibers: higher order effects , 1988 .

[6]  J. McKinney,et al.  Millimeter-wave arbitrary waveform generation with a direct space-to-time pulse shaper. , 2002, Optics letters.

[7]  Fei Zeng,et al.  Photonic Generation of Microwave Signals Based on Pulse Shaping , 2007, IEEE Photonics Technology Letters.

[8]  M. Nakazawa,et al.  Fabrication of non-linearly chirped fiber Bragg gratings for higher-order dispersion compensation , 1998 .

[9]  Jianping Yao,et al.  An Approach to Photonic Generation of High-Frequency Phase-Coded RF Pulses , 2007, IEEE Photonics Technology Letters.

[10]  Govind P. Agrawal,et al.  Nonlinear Fiber Optics , 1989 .

[11]  M Miyagi,et al.  Pulse spreading in a single-mode fiber due to third-order dispersion. , 1979, Applied optics.

[12]  M A Muriel,et al.  Real-time Fourier transformer based on fiber gratings. , 1999, Optics letters.

[13]  A. M. Kawalec.  SAW dispersive delay lines in radar signal processing , 1995, Proceedings International Radar Conference.

[14]  Jerry L. Eaves,et al.  Introduction to Radar , 1987 .

[15]  R O Claus,et al.  Polarization-independent all-fiber wavelength-division multiplexer based on a Sagnac interferometer. , 1995, Optics letters.

[16]  Bongkoo Kang,et al.  Linear frequency modulation of voltage-controlled oscillator using delay-line feedback , 2005, IEEE Microwave and Wireless Components Letters.

[17]  W. J. Bradford,et al.  Digital generation of high time-bandwidth product linear FM waveforms for radar altimeters , 1992 .

[18]  B. Jalali,et al.  Adaptive RF-photonic arbitrary waveform generator , 2003, IEEE Photonics Technology Letters.

[19]  Boualem Boashash,et al.  Estimating and interpreting the instantaneous frequency of a signal. I. Fundamentals , 1992, Proc. IEEE.

[20]  Bahram Jalali,et al.  Optically sculpt UWB waveforms , 2004 .