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We experimentally demonstrate a novel technique to process broadband microwave signals, using all-optically tunable true time delay in optical fibers. The configuration to achieve true time delay basically consists of two main stages: photonic RF phase shifter and slow light, based on stimulated Brillouin scattering in fibers. Dispersion properties of fibers are controlled, separately at optical carrier frequency and in the vicinity of microwave signal bandwidth. This way time delay induced within the signal bandwidth can be manipulated to correctly act as true time delay with a proper phase compensation introduced to the optical carrier. We completely analyzed the generated true time delay as a promising solution to feed phased array antenna for radar systems and to develop dynamically reconfigurable microwave photonic filters. 5293-5300 (1996). 5. Y. Liu, J. Yang, and J. Yao, "Continuous true-time-delay beamforming for phased array antenna using a tunable chirped fiber grating delay line," Photon.

A new architecture for active coherent beam combining of a large number of fibers is demonstrated. The approach is based on a self-referenced quadriwave shearing interferometer and active control with arrays of electro-optic ceramic modulators. Coherent phase combining of 64 independent amplified fibers is obtained. This is to our knowledge the highest reported number of combined fibers. A Strehl ratio degradation less than 2dB is achieved with a residual phase error <λ/10 rms.

We present the demonstration of an integrated frequency modulated continuous wave LiDAR on a silicon platform. The waveform calibration, the scanning system, and the balanced detectors are implemented on a chip. Detection and ranging of a moving hard target at upto 60 m with less than 5 mW of output power is demonstrated in this paper. Index Terms-Coherent LiDAR, frequency modulated continuous wave LiDAR, laser range finder, optical sensing and sensors, photonic integrated circuits. Patrick Feneyrou received the Ph.D. degree in nonlinear spectroscopy. Since 1998, he is with the Thales Research and Technology, Palaiseau, France. Since 2003, he is in charge of the theoretical analysis, system simulation, and development of proof of concept of LiDAR systems. He has developed several LiDAR systems for laser anemometry, temperature sensing, range finding, and velocimetry. Jérôme Bourderionnet received the Ph.D. degree in laser physics. Since 2001, he has been working with the

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