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Random code shifting based ultra-wideband photonic compressive receiver with image-frequency distinction.
Optics Express
|March 2, 2023
Summary
This study introduces an ultra-wideband photonic compressive receiver using random codes. The novel design expands receiving bandwidth and distinguishes true radio frequency signals from image frequencies.
Area of Science:
- Photonics
- Electrical Engineering
- Signal Processing
Background:
- Photonic compressive receivers offer wideband signal sensing capabilities.
- Existing systems face limitations in receiving bandwidth due to hardware constraints.
Purpose of the Study:
- To propose and demonstrate an ultra-wideband photonic compressive receiver with enhanced bandwidth.
- To overcome the bandwidth limitations of conventional photonic compressive receivers.
Main Methods:
- Utilizing random codes with shifted center frequencies to expand receiving bandwidth.
- Employing a slight difference in the center frequencies of two random codes for image-frequency distinction.
- Implementing a photonic compressive receiver architecture capable of flexible bandwidth expansion.
Main Results:
- Demonstrated sensing capability in the 11-41 GHz range using only two 780-MHz output channels.
- Successfully recovered complex signals including multi-tone spectra and sparse radar-communication spectra.
- Recovered signals comprised linear frequency modulated (LFM), quadrature phase-shift keying (QPSK), and single-tone signals.
Conclusions:
- The proposed photonic compressive receiver effectively expands receiving bandwidth beyond conventional limits.
- The image-frequency distinction method enables robust signal recovery in ultra-wideband scenarios.
- This technology holds promise for advanced radio frequency sensing and communication systems.
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