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

Abstract

A novel approach for realizing a microwave photonic image rejection mixer is presented in this paper. It is based on using a widely tunable narrow-band optical notch filter implemented by stimulated Brillouin scattering (SBS) to remove the image signal. The image rejection mixer has a simple structure as it only requires a single integrated dual-polarization modulator for both frequency conversion and pump wave generation for the SBS process. The absence of electrical components enables the image rejection mixer to be operated over a wide frequency range with a high image rejection ratio. A technique is also proposed to suppress the noise generated by the SBS process in the image rejection mixer. Experimental results demonstrate a high and constant image rejection ratio of over 32 dB for the image rejection mixer operating over an RF signal frequency range of 11.8-19.6 GHz, and around −5 dB conversion efficiency.

Broadband Image-Reject Mixing Based on a Polarization-Modulated Dual-Channel Photonic Microwave Phase Shifter

“…To evaluate the broadband operation capability of the proposed IRM, linearly frequencymodulated (LFM) signals with bandwidths of 1 GHz (11-12 GHz), 2 GHz (11-13 GHz) and 4 GHz (12)(13)(14)(15)(16) are served as the RF signals, and the LO signal is fixed at 10 GHz. The LFM signal is then down-converted by the proposed mixer to be 1-2 GHz, 1-3 GHz and 2-6 GHz, as the black solid curves of Figs.…”

“…Generally, there are two methods to suppress the images in the photonic microwave mixer. One is using electrical filters [11], [12] to directly remove the images in the received signals in the electrical domain, or using optical filters [13], [15] to remove the optical sidebands introduced by the images. This method has a simple structure but suffers from limited operation bandwidth and poor frequency tunability, and it would not be effective when the frequency of the IF signal is very small.…”

Broadband Microwave Photonic Mixer With High Spurs Suppression and Image Rejection

“…Moreover, the stimulated Brillouin scattering (SBS) effect is introduced into the IRMs [26]- [30]. The SBS gain spectrum of the pump light is used to amplify the +1st-order RF sideband [28] while the loss spectrum is utilized to attenuate the -1st-order RF sideband.…”

Microwave photonic mixer with high performance based on stimulated Brillouin scattering effect

“…Despite the avoidance of rare BPF through multiple-stage frequency conversion, this method involves numerous electro-optical modulators and erbium-doped fiber amplifiers (EDFAs), contributing to increased system complexity [10]. Furthermore, A Brillouin-assisted notch filter-based IRM is presented in [11]. The stimulated Brillouin scattering (SBS) loss spectrum of the pump boasts an extremely narrow bandwidth, effectively attenuating the image signal without impacting the RF sideband.…”