Improving thermal stability of opto-electronic oscillators

Tunable optoelectronic oscillator based on a chirped Mach-Zehnder modulator

“…As we know, the phase noise of OEO is mainly dependent on the fiber length 15 in proportion to the fiber length L 2 . 16 So the phase noise performance can be further improved if a longer loop is employed. But once the longer fiber is adopted, the fiber dispersion and the nonlinearity of fiber will introduce into the other noise and will worsen the phase noise of generated microwave signal.…”

Self-injection locked phase-locked loop OEO

“…On the other hand, the time domain phase dynamics of an injection locked VCO can be found as [23], (4) where o is the VCO output phase; i is the injection signal phase; =P inj /P o is the injection strength; Q is the quality factor of the VCO resonator; 3dB = 0 /2Q is half the 3dB bandwidth of the VCO resonator. Eq.…”

“…Moreover, a stable clock source are employed for either electrical or optical sampling of broadband information in analog to digital converters (ADC) as a prerequisite of number of other digital signal processing functions [1][2]. Improved stability and spectral purity of oscillators can be achieved in topologies such as phase-locked dielectric resonators, YIG, SAW, and quartz crystal oscillators [3][4][5] by combining electronic oscillators with high Q resonators such as quartz crystals resonators, acoustic resonators, ceramic resonators, dielectric resonators, and printed coupled resonators. Such resonators have low frequency resonant modes; hence a number of frequency multiplication stages are needed to reach the microwave regime.…”

Low-Cost Optoelectronic Self-Injection-Locked Oscillators

“…The higher external resonator or longer delay line can produce lower output phase noises for the fixed self-injection power. However, it is not an easy task to realize a long delay line with RF cables due to their large loss and high-devices are not easily available especially at very high frequencies [3].…”