Opto-Electronic Oscillator with Mach-Zender Modulator

Abstract

The non-standard opto-electronic oscillator (OEO) operation is discussed in the generation mode of a single-side optical harmonic on the base of external and internal modulation of the laser signal. The OEO mathematical model is formed basing on laser differential equations for the closed radiofrequency network. With the help of the model offered, the phase noise of OEO radiofrequency oscillations is analyzed. It is shown that phase noise reduction in the circuit with external modulation depends not only on the increased laser power and growth of the geometric length of the optical fiber, but on reduction of the laser phase noise.

Phase and amplitude fluctuations of oscillations in laser optoelectronic oscillator

“…Several experimental direct modulation the LOEO images were investigated, which worked at frequencies of 8 to 10 GHz and had quantum-sized lasers as a laser source, which worked at a wavelength of 1300 and 1550 nm, the optical fiber lengths were 60 to 4400 m. 14,15,17,18 The maximal output power of optical emission for used laser diodes formed about 10 to 30 mW. Using in OEO of the highly coherent laser with the phase noise less than −50 to 70 dB∕Hz (at the 10 kHz offset) is the condition of OEO small phase noises less than −110 dB∕Hz at the 10 kHz offset.…”

“…LOEO is capable of generating stable oscillations in the frequency range from 10 to 100 GHz with ultralow noise 8 – 15 LOEO is a promising small-sized device for navigation, radar, quantum informatics and quantum location, metrology, radio communications, gyroscopy, for Internet systems, precision radio frequency (RF) oscillations formation systems at frequencies 10 to 100 GHz at the low power of transmitters 4 – 14 Important is the creation of integral LOEOs small in size with a volume of 1×1×1 mm, with a short-term frequency instability of <10−14, resistant to large mechanical loads and acceleration (10−11 1/g).…”

“… – 15 LOEO is a promising small-sized device for navigation, radar, quantum informatics and quantum location, metrology, radio communications, gyroscopy, for Internet systems, precision radio frequency (RF) oscillations formation systems at frequencies 10 to 100 GHz at the low power of transmitters 4 – 14 Important is the creation of integral LOEOs small in size with a volume of 1×1×1 mm, with a short-term frequency instability of <10−14, resistant to large mechanical loads and acceleration (10−11 1/g). The development and implementation of low-cost integrated oscillators LOEO based on heterogeneous technologies will create the conditions for a technical revolutionary leap in various fields 8 …”

“…1(a)], LOEO phase noise reduction issues remain unresolved and poorly explained. The main advantage of the LOEO direct modulation circuit (or the coupled LOEO), unlike the LOEO external laser modulation circuit, for example, with a Mach–Zender modulator, 14 , 22 is the higher output power of the modulated radiation and the relative ease of implementation of the synchronization mode. To optimize the parameters of the LOEO scheme and establish the factors affecting the formation of fluctuations, the development of a special noise theory in LOEO is required.…”

“…In Refs. 12, 14, and 15, LOEO analysis was performed when considering a system of semiclassical laser equations with fluctuation sources. A feature of this work is the use of laser operator equations for analyzing noise properties, which make it possible to accurately describe fluctuations in the laser field strength in two level models above the threshold and justify the sources of fluctuations.…”