本論文主要探討藉光注入半導體雷射週期一非線性動態所產生的微波訊號之線寬及穩定度，並觀察光回饋對其之影響。在光注入半導體雷射系統中，藉由操作在特定光注入強度及光頻率差之情況下(如操作在光頻率差較小處或 Hopf bifurcation line 附近)，可產生線寬較小及穩定度較高的微波訊號，其將有利於提升測距應用上之解析度。由模擬結果與實驗結果可知，週期一微波訊號之線寬和不穩度會隨著光注入強度及光頻率差不同而改變。其原因為在不同操作條件下主雷射鎖住副雷射之能力有所不同，同時副雷射因光注入影響下其線寬和不穩度也隨之而有所變化所致。外加的光回饋及偏振旋轉光回饋系統會對光注入半導體雷射所產生的微波訊號之線寬及不穩度產生影響。不同的光頻率差、光注入強度、光回饋強度及延遲時間皆會影響微波訊號線寬及穩定度的變化程度，亦將影響測距應用上之解析度。此時改變週期一微波訊號線寬及不穩度的原因，除了光注入系統的影響外，也因副雷射的線寬及不穩度受外加的回饋系統而有所變化所致。

We study the linewidth and the frequency jitter of the photonic microwave signals generated using the period-one (P1) dynamics from an optically injected semiconductor laser. In the optical injection system, we demonstrate that the linewidth and the frequency jitter of the microwave signal can be reduced at the specific operating points. The improvement in the microwave signals is due to the improvement of the linewidth and the frequency jitter in the optically injected semiconductor laser. Locking between the master laser and the slave laser also reduces the jittering of the microwave signals generated. In this study, we also show that the linewidth and the frequency jitter of the photonic microwave can also be decreased by adding optical feedback or polarization rotated feedback to the optically injected semiconductor laser. The further reduction in the linewidth and the frequency jitter of the microwave signal is due to the reduction of the linewidth and the frequency jitter of the optically injected semiconductor laser when optical feedback or polarization rotated feedback is added.

[1] T. Kubota, M. Nara, and T. Yoshino, "Interferometer for measuring displacement and distance," Opt. Lett. 12, 310-312 (1987).
[2] A. Anghel, G. Vasile, R. Cacoveanu, C. Ioana, and S. Ciochina, "Short-range wideband FMCW radar for millimetric displacement measurements," IEEE Geosci. Remote Sens. Lett. 52, 5633-5642 (2014).
[3] M. U. Piracha, D. Nguyen, I. Ozdur, and P. J. Delfyett, "Simultaneous ringing and velocimetry of fast moving targets using oppositely chirped pulses from a mode locked laser," Opt. Express. 19, 11213-11219 (2011).
[4] J. W. Shi, F. M. Kuo, N. W. Chen, S. Y. Set, C. B. Huang, and J. E. Bowers, "Photonic generation and wireless transmission of linearly/nonlinearly continuously tunable chirped millimeter-wave waveforms with high time-bandwidth product at W-band," IEEE Photonics Technol. Lett. 6, 215-223 (2012).
[5] C. Wang and J. Yao, "Photonic generation of chirped microwave pulses using superimposed chirped ber Bragg gratings," IEEE Photonics Technol. Lett. 20, 882-884 (2008).
[6] H. Gao, C. Lei, M. Chen, F. Xing, H. Chen, and S. Xie, "A simple photonic generation of linearly chirped microwave pulse with large time-bandwidth product and high compression ratio," Opt. Express. 20, 23107-23115 (2013).
[7] L. Rumbaugh, W. D. Jemison, Y. Li, and T. A. Wey, "Wide bandwidth source for high resolution ranging," IEEE International Conference. 482-485 (2012).
[8] M. U. Piracha, D. Nguyen, and P. J. Delfyett, "Compensation of group delay ripple in chirped ber Bragg gratings and its application in chirped pulse laser radar," IEEE Photonics Conference. 646-647 (2012).
[9] S. K. Hwang, S. C. Chan, S. C. Hsieh, and C. Y. Li, "Photonic microwave generation and transmission using direct modulation of stably injection-locked semiconductor lasers," Opt. Commun. 284, 3581-3589 (2011).
[10] X. Fu, C. Cui, and S. C. Chan, "Optically injected semiconductor laser for photonic microwave frequency mixing in radio-over-ber," J. Electromagn. Anal. Appl. 24, 849-860 (2010).
[11] J. Dai, K. Xu, X. Sun, J. Niu, Q. Lv, and J. Wu, "A simple photonic-assisted microwave frequency measurement system based on MZI with tunable measurement range and high resolution," IEEE Photonics Technol. Lett. 22, 1162-1164 (2010).
[12] X. Q. Qi and J. M. Liu, "Photonic microwave applications of the dynamics of semiconductor lasers,"IEEE Photonics Technol. Lett. 17, 1198-1211 (2011).
[13] F. Y. Lin and J. M. Chen, "Generation of linearly chirped signal utilizing the instability region of an optically injected semiconductor laser," SPIE Conference. 6184,
6184M (2006).
[14] S. C. Chan, "Analysis of an optically injected semiconductor laser for microwave generation,"IEEE Photonics Technol. Lett. 46, 421-428 (2010).
[15] S. K. Hwang, J. M. Liu, and J. K. White, "Characteristics of period-one oscillations in semiconductor lasers subject to optical injection," IEEE Photonics Technol. Lett. 10, 974-981 (2004).
[16] S. C. Chan, S. K. Hwang, and J. M. Liu, "Radio-over-ber transmission from an optically injected semiconductor laser in period-one state," SPIE Conference. 6468, 646811 (2013).
[17] C. Cui and S. C. Chan, "Performance analysis on using period-one oscillation of optically injected semiconductor lasers for radio-over-ber uplinks," IEEE Photonics Technol. Lett. 48, 490-499 (2012).
[18] J. P. Zhuang and S. C. Chan, "Tunable photonic microwave generation using optically injected semiconductor laser dynamics with optical feedback stabilization," Opt. Lett. 38, 344-346 (2013).
[19] Y. H. Liao and F. Y. Lin, "Dynamical characteristics and their applications of semiconductor lasers subject to both optical injection and optical feedback," Opt. Express 21, 23568-23578 (2013).
[20] S. C. Chan and J. M. Liu, "Tunable narrow-linewidth photonic microwave generation using semiconductor laser dynamics," IEEE Photonics Technol. Lett. 10, 1025-1032 (2004).
[21] T. B. Simpson, J. M. Liu, M. AlMulla, N. G. Usechak, and V. Kovanis, "Linewidth sharpening via polarization-rotated feedback in optically injected semiconductor laser oscillators," IEEE Photonics Technol. Lett. 19, 1500807 (2013).
[22] S. C. Chan, S. K. Hwang, and J. M. Liu, "Period-one oscillation for photonic microwave transmission using an optically injected semiconductor laser," Opt. Express. 15, 14921-14935 (2007).
[23] T. B. Simpson, J. M. Liu, M. AlMulla, N. G. Usechak, and V. Kovanis, "Limit-cycle dynamics with reduced sensitivity to perturbations," Phys. Rev. Lett. 112, 23901 (2014).
[24] J. W. Dawson, N. Park, and K. J. Vahala, "An improved delayed self-heterodyne interferometer for linewidth measurements," IEEE Photonics Technol. Lett. 4, 1063-1066 (1992).
[25] H. Ludvigsen, M. Tossavainen, and M. Kaivola, "Laser linewidth measurements using self-homodyne detection with short delay," Opt. Commun. 155, 180-186 (1998).