Ladar Receiver Amplifier Circuit for Signal-to-Noise Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing compact LADAR systems face challenges with low signal-to-noise ratio, insufficient bandwidth, and large size due to complex alignments and high power consumption, making them inefficient for detecting non-metallic objects and achieving high spatial resolution.
Innovation Solution
A compact LADAR receiver design utilizing a tapered fiber bundle, large area photodetectors, and a novel amplifier circuit with a negative feedback mechanism to enhance signal-to-noise ratio and bandwidth, allowing for improved detection of targets at ranges up to 1000 meters with reduced power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a wide bandwidth photo detector/amplifier system with a small detector is used, then bandwidth is improved, but signal-to-noise ratio deteriorates
Solution Approach 1:
The patent transitions from a one-dimensional small detector to a two-dimensional large area photodetector array, enabling simultaneous capture of more photons (improving signal-to-noise ratio) while maintaining high bandwidth through the array architecture and associated amplifier circuitry
2Device complexity
If a co-axial or mono-static optical system is used, then system integration is improved, but device complexity and alignment difficulty worsen
Solution Approach 1:
The patent divides the optical system into separate transmit and receive paths, eliminating the need for complex beam splitters and polarizers required in co-axial systems. This segmentation allows independent optimization of each path and simplifies alignment procedures
3Measurement precision
If a large area photodetector is used, then signal-to-noise ratio is improved, but bandwidth deteriorates
Solution Approach 1:
The large area photodetector is divided into an array of smaller detector elements, each with its own amplifier circuit. This segmentation maintains high bandwidth for each element while the collective array captures more photons, achieving both high signal-to-noise ratio and high bandwidth
Solution Approach 2:
The patent uses a two-dimensional photodetector array where multiple small detectors work in parallel, effectively transitioning from a single large detector to a distributed array architecture that preserves bandwidth while improving signal-to-noise ratio
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 significantly improves the signal-to-noise ratio and bandwidth, enabling the detection of targets at extended ranges with reduced power consumption and compact size, suitable for applications in autonomous robots and UAVs, while maintaining image quality and eye safety.
Implementation Method 1
a sensor operatively connected to the tapered fiber bundle or light concentrator, the sensor comprising a photosensitive region and outputting a photocurrent
Implementation Method 2
a novel amplifier circuit with a negative feedback mechanism to enhance signal-to-noise ratio and bandwidth
Data Source
AI summary
A laser receiver comprising a sensor; a first amplifier operatively connected to the sensor comprising a first gate, a first source and a first drain; a first subcircuit operatively connected between the first drain and the first gate comprising a first resistor, a first inductor and a decoupling capacitor configured to allow the first amplifier bias to be established by the at least one first biasing resistor; the impedance of the first gate being sufficient such that only a small proportion of the current from the sensor passes into the first gate; an inductor connecting the first gate to the at least one biasing resistor with high impedance at the receiver operating frequency; a second amplifier comprising a second gate operatively connected to the first drain; and an output configured to be operatively connected to a processing unit and a display unit configured to displaying output and method thereof.