Guided-wave optical time delay network

A hybrid optical time delay unit using lithium niobate switches and precisely produced fiber loops is described. Three prototypes of the device were fabricated and characterized. The measured optical extinction ratio between time slots is typically /spl Lt/25 dB. On average, delay values are within 0.7% of their design values. The device is a 6-b (64 time slot) delay unit with 44 picosecond per increment.