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We experimentally demonstrate, for the first time, a method for arbitrary waveform generation (AWG) with time-bandwidth product (TBP) expansion beyond the limitations set by a spectral encoder. We show that, by using an anamorphic stretch transform with a specific group delay (GD) profile, one can boost the TBP of the generated electrical waveform in time-stretch AWG. In particular, we show that the TBP expansion can be achieved, depending on the signal sparsity and proper choice of the warped GD dispersion profile. The new waveform generation system is implemented here using a nonlinearly chirped fiber Bragg grating with a warped GD profile. Experimental demonstrations in this paper show a TBP expansion of more than three times above the maximum achievable using conventional methods. Details of the signal dependence and spectral redundancy/sparsity requirement for time-bandwidth compression and expansion are also studied. [ABSTRACT FROM AUTHOR]

To deal with the exponential increase of digital data, new compression technologies are needed for more efficient representation of information. We introduce a physics-based transform that enables image compression by increasing the spatial coherency. We also present the Stretched Modulation Distribution, a new density function that provides the recipe for the proposed image compression. Experimental results show pre-compression using our method can improve the performance of JPEG 2000 format. [ABSTRACT FROM AUTHOR]

The coherent time-stretch transform enables high-throughput acquisition of complex optical fields in single-shot measurements. Full-field spectra are recovered via temporal interferometry on waveforms dispersed in the temporal near field. Real-time absorption spectra, including both amplitude and phase information, are acquired at 37 MHz. [ABSTRACT FROM PUBLISHER]