Optical Correlation Receiver

Precise distance, time, and pulse width measurements are required for many areas of science and engineering. Time-of-flight methods are often used to measure remote distances. Optical signals are attractive because the small wavelength allows small transmit and receive telescopes. Short pulsed lasers are attractive sources that can provide high-distance measurement precision. Fast optical detectors are typically used at the receiver. Measurement precision is usually limited by the detectors’ temporal bandwidth. Picosecond and sub-picosecond pulses are difficult to measure and resolve. Optical autocorrelators have been used that employ nonlinear crystals. The optical autocorrelators require strong optical signals that can limit or preclude their use for remote, long-distance measurements.