All-Solid State Optical Terminal Using H-Tree Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical switch networks for LiDAR and laser communication systems are bulky, power-intensive, and require large numbers of emitters and phase shifters, making them impractical for applications like long-range laser communication.
Innovation Solution
An all-solid state optical transmit/receive terminal using a photonic chip with a nested array of binary optical switches in an H-tree pattern, where only a small subset of switches are operated at any given time, eliminating the need for mechanical components and phased arrays.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional optical switch networks use telescopes and gimbal systems for beam steering, then beam direction control is achieved, but the system becomes bulky and requires large moving systems with increased size, mass, and power consumption
Solution Approach 1:
The patent replaces mechanical gimbal systems and moving mirrors with an all-solid-state optical switch network implemented on a photonic chip. The beam steering function is achieved through optical switching between multiple fixed ports rather than mechanical movement, eliminating the need for heavy moving components while maintaining precise beam direction control
Solution Approach 2:
The patent transitions from one-dimensional mechanical rotation (gimbal) to two-dimensional port selection on a photonic chip. The H-tree optical switch network provides x-y plane beam steering by selectively activating different output ports, achieving angular control in both dimensions without mechanical complexity
2Measurement precision
If optical phased arrays are used for beam steering, then beam direction control is achieved, but a large number of emitters and phase adjusters are required, increasing system complexity and power consumption
Solution Approach 1:
The patent extracts the beam steering function from the emitter array itself and implements it separately through an optical switch network. Instead of controlling phases of many emitters, a single emitter feeds into an H-tree switch network that routes light to different output ports, achieving beam steering without requiring multiple phase-adjustable emitters
Solution Approach 2:
The patent combines multiple beam steering functions into a single optical switch network structure. The H-tree configuration integrates switching, routing, and beam direction control in one compact photonic chip, replacing the separate emitter arrays and phase shifters required by conventional phased arrays
3Adaptability or versatility
If conventional LiDAR and laser communication terminals use mechanical steering systems, then beam steering capability is achieved, but reliability decreases due to moving parts and power consumption increases
Solution Approach 1:
The patent replaces all mechanical steering components with solid-state optical switching. The photonic chip-based H-tree network provides beam steering through electronic control of optical switches rather than mechanical movement, eliminating wear, friction, and mechanical failure modes while improving reliability
Solution Approach 2:
The patent achieves dynamic beam steering capability without mechanical movement. The optical switch network can rapidly reconfigure beam directions by electronically controlling switch states, providing fast, reliable, and mechanically-free dynamic adaptation to different target positions
4Area of stationary object
If optical phased arrays with half-wavelength spacing are used for long-range laser communication, then required aperture size is achieved, but the number of emitters increases to 10^4, making the system impractical
Solution Approach 1:
The patent segments the aperture function from the emitter function. A single emitter feeds into an optical switch network that creates multiple virtual output channels. The H-tree structure divides the beam steering function into sequential switching stages, achieving large effective aperture without requiring proportionally large numbers of emitters
Solution Approach 2:
The patent implements a nested H-tree structure where switching stages are hierarchically arranged. Each stage divides the beam path into subsets, with inner stages handling finer angular resolution and outer stages providing coarser steering. This nested configuration achieves large aperture coverage with logarithmic scaling of switch numbers rather than linear scaling of emitter numbers
Data Source
Figure 1
Figure 2
Figure 3
AI summary
All-Solid State Optical Transmit/Receive Terminal An all-solid state optical transmit/receive terminal (100) includes binary optical switches (300-310) to steer an optical beam, without mechanical components, phased array of emitters/collectors or large number of phase shifters. A lens (102) optically couples a surface array of emitters/collectors to free space, giving each emitter/ collector a respective direction in free space. The emitters/collectors are also coupled, via an "H-tree" or other branched optical waveguide network, to a common input/output port (110), and from there to a receiver (112) and/or transmitter (114). The binary optical switches (300-310) are disposed at optical junctions of the optical waveguide network. ON switches pass an optical signal through the optical waveguide network, between the common input/output port and one or more selected emitter/collectors, thereby selecting a free space direction(s). Only a relatively small subset of the binary optical switches needs to be ON, therefore powered, simultaneously at any given time.