Advanced Optical Processing of Microwave Signals

Abstract

The authors present a review on the recent approaches proposed to implement transversal RF filters. Different tunable transversal filters consisting of wavelength tunable optical taps and those employing the tunability of dispersive devices are presented showing their high-performance characteristics. A comprehensive review of the fundamentals and a discussion on the main limitation of these structures are also included

High finesse compound optical ring filter for parametric multicasting RF channelization

“…The many THz of useful bandwidth available in optical waveguides positions RF photonics as a vital technique for radio communication and surveillance for wideband (tens of gigahertz) signals [1]. The implementation of a 100% duty cycle (i.e.…”

Continuously tunable incoherent microwave photonic filter using a tunable Mach‒Zehnder interferometer as the slicing filter

“…Equation (4) indicates that the MZI can be used as a comb slicing filter. The experimental set-up is shown in Figure 1.…”

“…Microwave photonic filters can also overcome the limitations of the traditional microwave filters, e.g., the electronic bottleneck and other sources of degradation [1][2][3]. Stable microwave photonic filter can be implemented in the incoherent operation regime since the phase fluctuation will not have much influence and consequently more stable to the environmental variation [4]. Several approaches to the implementation of some tunable incoherent microwave photonic filters were reported, among which sliced broadband light sources and dispersive media are widely adopted due to their advantages of cost-effectivity and low phase fluctuation noise [5,6].…”

Tunable and reconfigurable microwave photonic filter implemented by cascaded Mach-Zehnder modulators and a dispersive medium

“…Stable microwave photonic filter can be implemented in the incoherent operation regime, since the phase fluctuation will not have much influence and consequently more stable to the environmental variation [4]. Several approaches to the implementation of some tunable incoherent microwave photonic filters were reported, among which multi-wavelength optical source and dispersive medium based microwave photonic filters are widely studied due to their advantages of cost-effectivity and low phase fluctuation noise [5,6].…”