OPTICAL ANALOG-TO-DIGITAL CONVERSION, THE STATE OF THE ART

摘要

The conversion rate of purely electronic analog-to-digital converters is limited in speed to conversion rates of some Gsps. A way to obtain substantially higher conversion rates is the use of photonic circuits as input stage of an analog-to-digital converter. A comparison of different approaches for optical analog-to-digital conversion is given with special emphasis on the properties of the key optoelectronic components employed in the different concepts. In particular we report the state of the art of the development of optoelectronic modulators, Self-Electrooptic-Effect-Devices and photodiodes and discuss the limitations imposed by the device properties to the conversion schemes.