Integrated Optoelectronic Oscillator for Low Phase Noise Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optoelectronic oscillators (OEOs) are bulky, power-intensive, and vibration-sensitive, limiting their application due to discrete component assembly and high cost, which hinders the development of stable, low-phase-noise frequency synthesizers for commercial and military use.
Innovation Solution
The development of a monolithically integrated optoelectronic oscillation circuit using Silicon CMOS and BiCMOS technology, incorporating fiber optic delay lines, phase lock loops, and voltage-controlled oscillators to reduce phase noise and power consumption, with components such as optical Mach-Zehnder modulators and whispering gallery-mode resonators, integrated on a compact substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional discrete component assembly is used to build OEO, then the oscillator can be assembled with available components, but the device becomes bulky, power-intensive, and vibration-sensitive
Solution Approach 1:
The patent merges multiple discrete components (laser, modulator, photodetectors, delay lines, filters, and oscillators) into a single integrated optoelectronic chip. This integration eliminates the need for discrete component assembly, reducing the device size from bulky to compact, lowering power consumption, and improving vibration resistance while maintaining oscillation stability.
Solution Approach 2:
The patent implements a nested structure where multiple functional components are embedded within a hierarchical architecture: photodetectors and delay lines are integrated within the optoelectronic chip, which itself is part of a larger feedback loop system. This nesting allows compact packaging while preserving the functional complexity needed for stable oscillation.
2Object-generated harmful factors
If multiple discrete components are assembled to achieve low phase noise, then phase noise reduction is possible, but the device size, power consumption, and cost increase
Solution Approach 1:
The patent combines multiple phase noise reduction mechanisms (self-injection locking, self-phase locked looping, and self-mode locking) into a single integrated circuit. This merging achieves low phase noise performance previously requiring multiple discrete components while dramatically reducing device volume and power consumption.
Solution Approach 2:
The patent changes the physical parameters of the system by transitioning from discrete to integrated components. This parameter change enables the same phase noise reduction functionality to be achieved in a compact form factor with lower power consumption and reduced cost.
3Object-generated harmful factors
If discrete components are used to implement self-ILPLL, then phase noise reduction can be achieved, but the device becomes sensitive to vibration and G-forces
Solution Approach 1:
The patent merges all vibration-sensitive discrete components into a rigid integrated optoelectronic chip structure. This integration eliminates relative motion between components during vibration, making the device resistant to G-forces and mechanical shock while maintaining the phase noise reduction capabilities of self-ILPLL.
Solution Approach 2:
The patent uses a rigid integrated chip structure that acts as a protective shell, eliminating the need for fragile discrete component mounting. This integrated structure naturally resists vibration and G-forces that would otherwise affect loosely coupled discrete components.
4Ease of manufacture
If conventional OEO design is used, then the oscillator can be built with discrete parts, but manufacturing cost and real estate requirements increase
Solution Approach 1:
The patent merges all discrete components into a single integrated optoelectronic chip that can be manufactured using standard semiconductor fabrication processes. This eliminates the need for manual assembly of multiple discrete parts, reducing both manufacturing cost and real estate requirements while maintaining the functional complexity of self-ILPLL.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach results in a compact, low-power, and cost-effective OEO with significantly reduced phase noise, enabling stable frequency synthesis and improved temperature stability, suitable for various applications including cellular technologies and radar systems.
Implementation Method 1
an optical source, such as a laser
Implementation Method 2
an optical Mach-Zehnder modulator
Implementation Method 3
The energy is converted into radio frequency (RF) and microwave signals
Implementation Method 4
at least one fiber optic delay line configured to receive a first portion of the optical signal
Implementation Method 5
whispering gallery-mode resonators
Data Source
Figure 1a
Figure 1b
Figure 2
AI summary
The present invention details fabrication guidelines of integrated optoelectronic oscillators (100) with frequency and phase stability, having higher frequency selectivity in a relatively small size (compared to the larger size of a higher order electrically realized RF filter), reduced temperature sensitivity, and minimized frequency drift. The integrated photonic components (101, 103, 105, 107) and RF oscillator (140) may use Silicon photonics and microelectronic integration using CMOS and BiCMOS technology, eliminating the need for bulky and/or discrete optical and microwave components.