Distributed Pseudorandom Ranging for Detection Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ranging systems, such as sonar and radar, face challenges in detecting reflections from objects when surface conditions or orientations are not properly aligned with the transmitted signals, leading to reduced detection efficiency.
Innovation Solution
The use of pseudorandom signals transmitted from distributed sources, where each transmitter is assigned a unique pseudorandom sequence with strong auto-correlation and weak cross-correlation qualities, increases the likelihood of reflections being received by the receiver, even under adverse conditions, by ensuring that signals can be specifically identified and their times of flight calculated for determining object distances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single transmitting element and single receiving element are used in synthetic aperture operation, then the system structure is simple, but the detection reliability deteriorates when object surfaces are not properly aligned with transmitted signals
Solution Approach 1:
The patent divides the single transmitting element into multiple distributed transmitting elements, each assigned a unique pseudorandom sequence. This segmentation allows the system to transmit signals from multiple spatial locations simultaneously, increasing the probability that at least one signal will reflect off the object surface toward the receiver, thereby improving detection reliability without requiring complex coordinated control of a phased array.
Solution Approach 2:
The patent changes the signal parameter by assigning unique pseudorandom sequences to each transmitting element. This allows the receiver to distinguish between signals from different transmitters through correlation processing, enabling reliable detection even when individual signals are weak or reflected at unfavorable angles. The pseudorandom sequences provide strong autocorrelation properties that enhance signal identification.
2Reliability
If signals are transmitted from distributed sources with unique pseudorandom sequences, then the probability of signal reflection and accurate detection is improved, but the device complexity increases
Solution Approach 1:
The pseudorandom sequences are designed to have strong autocorrelation properties, allowing each transmitted signal to identify itself through correlation processing at the receiver. This self-identification capability simplifies the receiver design, as it can autonomously distinguish between different transmitted sequences without requiring complex external synchronization or coordination mechanisms.
Solution Approach 2:
By encoding unique pseudorandom sequences in each transmitter's signal, the system transforms the complexity from spatial coordination to signal processing. The receiver uses correlation with the known pseudorandom sequences to identify and measure signals from specific transmitters, converting a potentially complex multi-element coordination problem into a more manageable signal recognition task.
3Measurement precision
If pseudorandom sequences with strong auto-correlation and weak cross-correlation are used, then the precision of time of flight calculation is improved, but the manufacturing precision requirements increase
Solution Approach 1:
The patent uses computationally generated pseudorandom sequences rather than physically manufactured precise timing signals. These sequences can be generated digitally with high precision using standard algorithms, avoiding the need for complex physical synchronization hardware. The sequences are essentially disposable software constructs that can be regenerated identically without degradation.
Solution Approach 2:
The patent replaces mechanical or physical precision timing mechanisms with electronic pseudorandom sequence generation and correlation. Instead of relying on precise physical clock synchronization across distributed transmitters, the system uses digital signal processing with pseudorandom codes to achieve precise time of flight measurements, substituting mechanical precision requirements with computational methods.
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 enhances the probability of signal reflection and accurate distance calculation, regardless of surface conditions or interference, allowing for improved object detection and mapping in various environments.
Implementation Method 1
capturing a plurality of reflections of the plurality of pseudorandom signals from a plurality of objects
Implementation Method 2
determining a plurality of distances to the plurality of objects based on respective times of flight of the plurality of pseudorandom signals
Data Source
AI summary
Ranging systems operate based on the transmission and receipt of pseudorandom sequences. Pseudorandom sequences may be generated and assigned to specific transmitters, which may operate simultaneously to transmit signals including the pseudorandom sequences. A receiver may be programmed to recognize the specific pseudorandom sequences within data captured by the receiver, and to associate the pseudorandom sequences with the transmitters that transmitted them. Upon identifying the pseudorandom sequences, the receiver or one or more associated components may calculate times of flight of signals transmitted by the respective transmitters. Such times of flight may be used to calculate distances to one or more objects from which the signals were reflected.