| 摘要 |
An optical switch network which includes a plurality N of cascaded optical switching stages, each mth one of the switching stages including 2m-1 Mach-Zehnder interferometers, where m=1 through N. The input port of the Mach-Zehnder interferometer of a first one of the optical switching stages receives an optical input signal, and the 2N-1 Mach-Zehnder interferometers of the Nth one of the optical switching stages provide a total of 2N output ports. Each of the Mach-Zehnder interferometers is preferably an unbalanced Mach-Zehnder interferometer, and the optical input signal preferably has a wavelength which is a selected one of 2N selectable wavelengths. The plurality N of cascaded optical switching stages provide 2N possible optical paths, whereby the optical input signal is automatically routed along a selected one of the 2N possible optical paths in dependence upon its selected wavelength. Also disclosed is an optical time delay network comprised of an optical switch network as described above, and a plurality 2N of optical delay lines of different lengths coupled to respective ones of the 2N output ports of the Nth one of the optical switching stages, each of the optical delay lines being comprised of an optical waveguide having a light-reflecting end, whereby the optical input signal is automatically routed from the input port of the first one of the optical switching stages to a selected one of the 2N output ports of the Nth one of the optical switching stages, and thence, into a respective one of the 2N optical delay lines, in dependence upon its selected wavelength, whereby the optical time delay network is wavelength-addressable. Also disclosed is a phased array antenna which includes a plurality of optical time delay networks like the one described above, whereby a beam produced by the antenna elements of the phased array antenna has a beam angle which is a selected one of 2N selectable beam angles, in dependence upon the wavelength of the optical input signal. |
