Optical delay network e.g. for microwave antenna, has delay lines with different defined lengths of optical fibre

摘要

The network includes several delay stages with at least two semiconductor laser amplifiers (V) acting simultaneously as optical switches. The fibre lengths of each delay line in the delay line in the delay stages differ by a defined amount from the others. n x n couplers connect the delay stages together, and connect the transmitter (S1 or S2) to the first delay stage, and the last delay stage to the receiver (E1,E2). The transmitter may be a directly or externally-modulated semiconductor laser. The receiver may be a pin-photodiode with a suitable pre-amplifier and main amplifier.