Abstract: Disclosed is a method of processing input data in a processor. The method comprises providing a plurality of radio frequency (RF) signals, each comprising a plurality of RF frequencies with respective component values representing input data, and providing a plurality of optical signals, each optical signal having a respective optical frequency. Each optical signal is modulated with one of the RF signals to generate modulated optical signals. Processing operations are performed on the modulated optical signals in parallel to derive a processor output. Also disclosed is a processor for processing input data according to the method.