Oscillators are widely used in several fields such as telecommunications, measurement systems, computing, on board systems, especially in aeronautics and space research. They are devices required in emitters and receivers for transmission and extraction of information. Oscillators used to be completely electrical devices but nowadays they are hybrid mixed in photonics due to bandwidth requirements.
Some of the advantages that optoelectronics have are bandwidth, electromagnetic interference immunity, reduced losses due to the use of optical fiber instead of wires.
In the mid 90s a novel oscillator configuration made appearance, it was the optoelectronic oscillator OEO [1]. After this first result, this technique has been quickly developed and improved by several research groups, assuring today an important frequency increase (tenths of GHz) and high spectral purity (phase noise lower than -150 dBc/Hz with 10 kHz offset); having by this properties an alternative high frequency oscillator [2].
The use of recent optical technologies gives wide possibilities to enhance and evolve for OEOs. In this project we are strongly interested in a particular OEO architecture known as VCSEL Based Optoelectronic Oscillators (VBOs); these oscillators use a vertical cavity surface emitting laser (VCSEL) instead of DFB lasers [3]. These oscillators have been widely studied by MOSE (Micro-ondes et Optronique pour Systèmes embarqués) research group from ISAE (Institut Supérieur de l'Aéronautique et de l'Espace) and they offer attractive characteristics in terms of size, cost reduction and energy consumption. Results in VBO technique show the feasibility of VCSELs use in OEOs, -120 dBc/Hz with 10 kHz offset phase noise signals have been generated [4].
This project looks forward to design and implement an Injection Locked VCSEL Based Oscillator (ILVBO). The ILVBO architecture is basically the same VBO architecture but using an injection locked VCSEL instead of a single VCSEL as light source. Figure 1 presents the ILVBO architecture.
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