Multichannel Photonic Receiver Using Master Oscillator Injection Locking

Solution Overview

Problem

Existing single channel photonic modules are not suitable for multichannel applications due to size, cost, and performance constraints, particularly in space and airborne environments where compactness, reduced mass, and lower costs are required while maintaining optical power and frequency performance.

Innovation Solution

An integrated multichannel photonic receiver system that uses a single master oscillator to drive multiple channel lasers, reducing the number of active elements and passive filters, and employs injection locking and optical combiners to generate down-converted or up-converted signals, avoiding fiber coupling for improved compactness and redundancy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple independent laser sources and modulators are used for each channel, then channel performance and reliability are improved, but system size, mass, and cost increase significantly

Engineering Contradiction:

Improvechannel performanceVSAvoidsystem mass

Core Design Contradiction:

ReliabilityVSWeight of stationary object

Solution Approach 1:

Multiple channel lasers are merged into a single laser source that is injection-locked to generate multiple wavelength channels. This consolidation reduces the number of independent laser sources from N (one per channel) to just one master laser, significantly reducing system mass while maintaining all required channel functions

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

A single master laser source performs multiple functions by generating wavelengths for all N channels through injection locking. The master laser universally serves all channels instead of each channel having its own dedicated laser, reducing overall system mass while maintaining channel performance

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If multiple independent laser sources and modulators are used for each channel, then channel performance and reliability are improved, but system cost increases significantly

Engineering Contradiction:

Improvechannel performanceVSAvoidsystem cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

Multiple channel lasers are merged into a single laser source that is injection-locked to generate multiple wavelength channels. This consolidation reduces the number of independent laser sources from N (one per channel) to just one master laser, significantly reducing system mass while maintaining all required channel functions

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

A single master laser source performs multiple functions by generating wavelengths for all N channels through injection locking. The master laser universally serves all channels instead of each channel having its own dedicated laser, reducing overall system mass while maintaining channel performance

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If traditional fiber coupling is used to combine multiple channels, then channel isolation is maintained, but system compactness is reduced

Engineering Contradiction:

Improvechannel isolationVSAvoidsystem volume

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

Traditional mechanical fiber coupling systems are replaced with an integrated photonic circuit approach where waveguides and optical components are fabricated on a single chip. This substitution eliminates the need for precise mechanical fiber alignment and coupling, achieving channel isolation through integrated waveguide design while dramatically reducing system volume

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

The solution enables a compact, cost-effective, and mass-efficient multichannel receiver system with redundancy, meeting performance requirements for space and airborne applications by using fewer laser and modulator components and eliminating fiber coupling issues, thus reducing size and cost while maintaining performance.

Implementation Method 1

The subject technology uses an injection locking approach in which several individual channel lasers, driven by a single oscillator laser, can drive each channel, all with the same wavelength

Methodology Applied

Scientific EffectInjection locking:

Implementation Method 2

A combiner performs a heterodyne process by mixing the LO signal with the M filtered RF-modulated optical signals

Methodology Applied

Scientific EffectHeterodyne: Heterodyne

Data Source

PatentUS9876582B2Integrated multichannel photonic receiver

Publication Date: 2018.01.23 LOCKHEED MARTIN CORP

AI summary

An integrated multi-channel photonic radio-frequency (RF) receiver system includes a master oscillator including a laser source configured to generate laser light. A local oscillator (LO) path may include an LO generator, an LO modulator, an optical LO filter, and an optical amplifier optically coupled to one another to generate an LO signal. Multiple RF-modulation channels are coupled through an optical switch to a number of channel filters and configured to produce a number of filtered RF-modulated optical signals. An optical combiner may combine the LO signal with each filtered RF-modulated optical signal to generate down-converted optical signals. Each channel of the plurality of RF-modulation channels includes a channel laser coupled to a channel modulator, and the LO generator and channel lasers of the RF-modulation channels are fed by the laser light of the master oscillator.