Advancing microwave waveform generation: photonic dual linear chirp modulation with configurable bandwidth

Abstract

Microwave waves play a crucial role in various fields, including data transmission, sensing applications, and seismology. The advancement of technology has led to the increased use of microwave waves due to their wider bandwidth and higher frequency capabilities. However, conventional electrical systems often produce microwave waveforms with limited bandwidth and predefined frequency ranges, which may not be suitable for all applications. In this study, we focus on producing an arbitrary dual linear chirped microwave signal that offers configurable bandwidth within a predetermined frequency range. Our approach relies on optical external modulation as the foundation of the photonic method. By cascading two Mach-Zehnder Modulators (MZMs) functioning at the Minimum Transmission Point (MITP), we effectively suppress carrier signals in the modulated output. Through this technique, we successfully generate dual linear chirp microwave signals by superimposing an electrical baseband chirp signal onto the externally modulated signal in the optical domain. This approach demonstrates the potential to create microwave waveforms with wide bandwidth and linear chirping, opening up new possibilities in satellite communication, radar systems, and other advanced applications.