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Dichromatic coherent pumping of optical microresonators possessing broadband Kerr nonlinearity reveals a rich variety of nonlinear and critical phenomena, including time‐translation symmetry breaking, multistability, and chaos. This pumping scheme has garnered significant interest owing to its practical applications arising from optical‐to‐microwave frequency stability transfer and frequency‐division phase noise reduction. In this work, a generalized analytical model is developed to elucidate the dynamics of dissipative Kerr cavity solitons as particles in dual‐frequency pumped Kerr cavities. The model offers quantitative and intuitive insight into the behavior of the system both within and beyond the locking range wherein solitons synchronize to the two driving lasers. It also predicts new phenomena and expounds hitherto unexplained experimental observations covering bistability, hysteresis, and Arnold tongues. The unified framework simultaneously delineates the parameter space for the existence of dissipative discrete time crystals recently reported in dually pumped optical solitons. Bridging a fundamental study with practical applications, this work offers valuable understanding of two‐point injection‐locked microcombs for realizing chip‐scale optical clocks and superior microwave photonic oscillators.
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Software Defined Radio Injection-Locking using a GPS signal for multichannel coherent receivers
This paper explores the potential benefits of combining the use of injection-locking techniques with GPS signals as a common clock source when applied to a low-cost Software Defined Radio (SDR) to improve the accuracy of coherent multiple receivers. Coherent systems impose severe requirements on the frequency stability of the signal source at the receiver. In this work, injection-locked oscillators are used as local clock receivers, which inherently synchronizes the SDR analog digital converter (ADCs) sampling times and keeps the local oscillator locked on to the GPS stimulus periodic signal. This paper illustrates the hardware modifications needed for to the injection locking oscillators of eight RTL-SDR radios and the theory behind it, and experimentally measures the degree of coherency in the frequency, phase and time synchronization to verify the proposed method. The coherency demonstrated in the results prove the feasibility of using beamforming, multiple input multiple output (MIMO) and RF transmitter geo-localization.
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- PAR ID:
- 10519037
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-9032-0
- Page Range / eLocation ID:
- 1 to 10
- Subject(s) / Keyword(s):
- SDR receiver coherency beam-forming, MIMO, transmitter geolocation.
- Format(s):
- Medium: X
- Location:
- Big Sky, MT, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/AERO55745.2023.10115547
