Photonic Generation of Dual-Chirp Waveforms With Improved Time-Bandwidth Product

We present a photonic method for the generation of dual-chirp signals. In this approach, a single-tone RF signal is first modulated using a modulator in order to generate two optical carriers, which are further modulated by a linearly chirped signal by another modulator. Square-law detection in a photodiode then generates a dual-chirp signal whose center frequency and time-bandwidth product (TBWP) are fourfold increased. The dual-chirping and the improved TBWP can improve the range resolution of the radar system and help avoid the range measurement error caused by the range-Doppler coupling effect. The generation of bandwidth-quadrupled S-band dual-chirp waveforms is demonstrated experimentally. The processing of the dual-chirp signal is also discussed, in order to show its advantages over single-chirp signals. We believe that the proposed approach is a potential solution for the generation of dual-chirp signals with high center frequency and large bandwidth in modern radar systems.

[1]  Mark A. Richards,et al.  Fundamentals of Radar Signal Processing , 2005 .

[2]  Andrew M. Weiner,et al.  Recent Advances in Programmable Photonic-Assisted Ultrabroadband Radio-Frequency Arbitrary Waveform Generation , 2015, IEEE Journal of Quantum Electronics.

[3]  Robert J. Fitzgerald,et al.  Effects of Range-Doppler Coupling on Chirp Radar Tracking Accuracy , 1974, IEEE Transactions on Aerospace and Electronic Systems.

[4]  H. Fetterman,et al.  Demonstration of 110 GHz electro-optic polymer modulators , 1997 .

[5]  Hongwei Chen,et al.  A simple photonic generation of linearly chirped microwave pulse with large time-bandwidth product and high compression ratio. , 2013, Optics express.

[6]  S. Pan,et al.  Linearly chirped microwave waveform generation with large time-bandwidth product by optically injected semiconductor laser. , 2016, Optics express.

[7]  Ilan Rusnak,et al.  Method of measuring closing velocity by transmitting a dual-chirp signal , 2010, 2010 IEEE 26-th Convention of Electrical and Electronics Engineers in Israel.

[8]  Weisheng Hu,et al.  Photonic generation of phase-stable and wideband chirped microwave signals based on phase-locked dual optical frequency combs. , 2016, Optics letters.

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

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

[11]  Norio Tagawa,et al.  Doppler measurement using a pair of FM-chirp signals , 2003, IEEE Symposium on Ultrasonics, 2003.

[12]  Andrew M. Weiner,et al.  Photonic Radio-Frequency Arbitrary Waveform Generation With Maximal Time-Bandwidth Product Capability , 2014, Journal of Lightwave Technology.

[13]  Jianping Yao,et al.  Dual-Chirp Microwave Waveform Generation Using a Dual-Parallel Mach-Zehnder Modulator , 2015, IEEE Photonics Technology Letters.

[14]  Wei Pan,et al.  Photonic-assisted chirped microwave pulses generation with a flexible and fine parameter manipulation. , 2016, Optics express.

[15]  Yaakov Buchris,et al.  Asynchronous Transmitter Position and Velocity Estimation Using A Dual Linear Chirp , 2014, IEEE Signal Processing Letters.

[16]  Jianping Chen,et al.  Generation of a widely tunable linearly chirped microwave waveform based on spectral filtering and unbalanced dispersion. , 2015, Optics letters.