Broadband true time-delay with optical coherent transients

Summary form only given. When phased array antenna systems operate with broadband (multiple gigahertz) signals, true time-delay devices are needed to solve the problem of beam squint. Optical coherent transient technology, also known as spatial-spectral holography, offers a unique way of using the space and frequency dimensions of inhomogeneously broadened absorbers to handle thousands of high-resolution delays in a compact volume. We demonstrated broadband true-time delay in a Tm/sup 3+/:YAG crystal, which offers delays up to a microsecond on signals having several tens of GHz bandwidth with sub-picosecond delay resolution.