Photonic Generation and Detection of Chirped Millimeter-Wave Signal by a W-Band Photonic Transmitter

• Main Authors: Lu, Chun-Liang, 盧俊良
• Other Authors: Pan, Ci-Ling
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/86929525381700144648

碩士 === 國立清華大學 === 光電工程研究所 === 100 === We study chirped millimeter-wave (MMW) generation and detection using a photonic transmitter (PT) and the Fourier-transform pulse shaping technique. Utilizing the basic concepts of frequency-to-time mapping, we explore generation and control of the effects of chirped MMW. Experimentally, one of the key components is a W-band PT. We achieved coherent detection of the n MMW signal by the THz-time domain spectroscopic (THz-TDS) technique. The excitation and probing light is a mode-lock Er:doped fiber laser with a center wavelength of 1560nm. In this thesis, we proposed and demonstrated two different kinds of frequency -modulated MMW signal. The first one is a linearly chirped MMW waveform. We design the envelope to be a Gaussian-like curve in the optical spectra of the excitation laser, the envelope curve of the generated linearly chirped MMW waveform is also a Gaussian-like curve. The time-bandwidth product is 6.03. The second one is the step chirped MMW waveform. We enhance the number of shaped pulses and the time-bandwidth product achieved to 32.17. In the mean time, we setup and demonstrate a mathematical simulation model. The simulation results agree with the experimental results. As shown the the experimental results, we can arbitrarily tune the amplitudes and frequencies of the time domain MMW waveform through suitable design of the optical spectrum of the exciting light. Further, this method can increase the time resolution of the MMW pulse compression radar system.