Photonic downconversion and microwave-to-digital subsystems

Frequency downconversion is an essential part of many RF systems and is particularly important in microwave to digital systems. Photonic technology offers numerous potential benefits including very broad bandwidths, low loss signal transport over optical fiber, and various physical advantages related to fiber transport including electromagnetic interference immunity and signal multiplexing. The key to realizing these advantages is the efficient conversion from the electrical-to-optical and optical-to-electrical domain. In this paper, system design issues are discussed to take full advantage of recently available photonic technology including photonic downconversion and downsampling. These concepts are discussed and demonstrated within the context of two promising photonic microwave to digital architectures.