Abstract: Systems and methods are disclosed herein to provide analog-to-digital converter techniques. For example, in accordance with an embodiment of the present invention, an analog-to-digital converter architecture is disclosed that utilizes optical techniques to convert an analog electrical signal to a digital electrical signal.

Abstract: Systems and methods are disclosed herein to provide various optical techniques. For example, in accordance with an embodiment of the present invention, a pulse position modulation discriminator architecture is disclosed for discriminating temporal positions of PPM-encoded optical pulses by converting them from time modulated to frequency modulated signals. As another example, time division multiplexed optical signals may be translated to wavelength division multiplexed optical signals. One or more of the architectures disclosed herein may be implemented, for example, to provide PPM to FM or time to wavelength conversion for receiver or transmitter applications.

Abstract: A high extinction ratio interferometer is disclosed. The interferometer includes a first and second optical fiber each having a first end and a reflective end and an optical coupler for coupling the first optical fiber and the second optical fiber between their first ends and their reflective ends. The first optical fiber provides a first optical path from the optical coupler to its reflective end and back to the optical coupler and the second optical fiber provides a second optical path from the optical coupler to its reflective end and back to the optical coupler. The second path is greater than the first path by a delay length and the first path and the second path are each less than approximately 20 cm. The interferometer finds application as a differential phase shift keyed (DPSK) demodulator, particularly useful in a satellite system employing inter-satellite communication.

Abstract: A system for controlling a relative length a first optical fiber and a second optical fiber includes a first heater coupled to the first optical fiber, a second heater coupled to the second optical fiber, and a controller coupled to the first heater and the second heater. The controller operates the first heater in response to a temperature less than a predetermined temperature and operates the second heater in response to the temperature greater than the predetermined temperature. This allows the length of the optical fibers to be maintained evenly.