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Optical methods are employed in various fields from communications to space research to improve the system performance. Each application uses different properties of light and light-matter interaction. For example, ultra-high frequency nature of light is desirable in applications like ranging and velocimetry to increase the resolution. On the other hand, in the telecommunication industry, ultra-wide bandwidth of the fibers is utilized with time and wavelength multiplexing techniques that make Gigabit internet possible today. Such multiplexing techniques are also useful in photonic assisted analog to digital converters (ADC) that multiply the sampling rates of electronic ADCs. Additionally, ultra-low (

Dispersive Fourier Transform (DFT) is a measurement technique that facilitates wavelength to time mapping through optical dispersive elements with large and linear group velocity dispersion (GVD) such as dispersive fibers or chirped fiber bragg gratings (CFBG). This technique has been applied to several scientific and industrial applications such as analog to digital converters to increase effective sampling rates, spectroscopy to enable single-shot real-time spectral measurements, optical arbitrary waveform generation, and real time imaging to capture fast dynamic processes.In this work, Dispersive Fourier Transformation and its application on real time imaging are investigated. We demonstrated a fast dispersive laser scanning system that can achieve horizontal scanning through Raman amplified DFT and diffraction grating system and vertical scanning by employing MEMS based digital micro mirror arrays technology. The proposed technique employs real time dispersive imaging system, which captures spectrally encoded images with a single photodetector at pulse repetition rate via space-to-time mapping technology. Wide area scanning capability is introduced by using individually addressable micro mirror arrays as a beam steering device.Experimentally, we scanned ∼20mm2 at scan rate of 5kHz with ∼150μm lateral and ∼160μm vertical resolution that can be controlled by using 1024x768 mirror arrays. With the current state of the art MEMS technology, fast scanning up to 32.5kHz scan rate and resolution down to single mirror pitch size of 10.8μm is also achievable. Moreover, we investigated and demonstrated the ideas to improve the system to achieve larger area scan with faster scan rates and higher resolution while optimizing power.

Theoretical Derivation and Extended Experimental results

Omnidirectional Optical Antennas (OOA) with 360o Field of Regard along with full-duplex laser communication capability can play a remarkable role in achieving sophisticated CubeSat mission that can achieve high speed (≥1Gbps), long distance (≥50km) data communication, data relaying among CubeSats and that processes formation flying ability. In this paper, we discuss miniature optical antenna design optimization techniques using COTS components to facilitate OOA development. In particular, we present challenges involving design tradeoffs among scanning mirror size, scanning angle, transmit beam width, beam divergence, pointing accuracy requirements and component availability in a SWaP-C limited system. We show that to achieve maximum SNR at long distance, the transmit laser beam diameter to mirror diameter ratio needs to be 0.8-0.9. Moreover, we show that the peak intensity varies and can decrease up to 70% over the mirror scanning range depending on transmitter beam size. Furthermore, we explain the effect of laser peak power, initial beam size and communication distance on Effective Communication Beam Width (ECBW) to maintain SNR≥10dB at 1Gb/s. We show that by choosing the optimum components and parameters an ECBW of ≥50m at 50km distance is achievable. Therefore, the communication link can endure angular disturbance of 50 μrad - 180.5 μrad.