Instantaneous high-resolution multiple-frequency measurement system based on frequency-to-time mapping technique

Abstract

A new microwave photonic instantaneous frequency measurement system that can simultaneously measure multiple-frequency signals while achieving very high resolution and wide frequency measurement range is presented. It is based on the frequency-to-time mapping technique implemented using a frequency shifting recirculating delay line loop and a narrowband optical filter realized by the in-fiber stimulated Brillouin scattering effect. Experimental results demonstrate the realization of a multiple-frequency measurement capability over a frequency range of 0.1-20 GHz that can be extended to 90 GHz, and with a measurement resolution of 250 MHz.

Wide-range, high-precision multiple microwave frequency measurement using a chip-based photonic Brillouin filter

“…Photonic IFM has shown potential for a wide measurement range of 50 GHz [5], a high accuracy of 400 kHz [6], and can be integrated on-chip [7]. Additionally, the ability to measure simultaneous multiple frequencies is highly attractive in realistic spectrally cluttered environments [8]. However, these advantages have not been achieved simultaneously in a single system, due to the fundamental trade-off between measurement range and accuracy.…”

Brillouin-Assisted Notch Filtering Based All-Optical Image Rejection Mixer

“…1(c) can be neglected as they are outside the IRM instantaneous bandwidth, which is limited by the Brillouin linewidth of the SBS medium and is around 15 MHz for a silica fibre. Techniques such as frequency modulating [25] or phase modulating [26] the pump wave have been reported to increase the Brillouin linewidth to hundreds of megahertz. This can be used to increase the instantaneous bandwidth of the SBS based IRM.…”

Photonic-Assisted Instantaneous Frequency Measurement System Based on a Scalable Structure

“…To obtain the frequency of an unknown microwave signal, it is necessary to map the frequency to certain optical or electrical parameters. So far, numbers of IFM schemes have been proposed [4]- [15]. In these schemes, the frequency of the unknown microwave signals can be obtained through methods based on frequency-power mapping [4]- [11], frequency-space mapping [12], [13] and frequencytime mapping [14], [15].…”

“…So far, numbers of IFM schemes have been proposed [4]- [15]. In these schemes, the frequency of the unknown microwave signals can be obtained through methods based on frequency-power mapping [4]- [11], frequency-space mapping [12], [13] and frequencytime mapping [14], [15]. For the frequency-space mapping techniques, the laser is modulated with an unknown microwave signal, and then the different spectral components in the optical domain are separated in space by means of a spatial filter such as a Bragg grating Fabry-Perot (BGFP) device [12] or a diffraction grating [13].…”

“…In [14], the frequency measurement is based on the principle that the different frequency components have different propagation speeds in the dispersive medium. In [15], different spectral components are separated in the time domain using frequency shifted recirculating delay loops and narrowband optical filters.…”