An investigation is reported of acousto-optical and fibre-optic Fourie
r processors of electric signals, based on semiconductor lasers. A des
cription is given of practical acousto-optical processors with an anal
ysis band 120 MHz wide, a resolution of 200 kHz, and 7 cm x 8 cm x x 1
9 cm dimensions. Fibre-optic Fourier processors are considered: they r
epresent a new class of devices which are promising for the processing
of gigahertz signals.