Drone RF Frequency Hopping Estimation With RANSAC Outlier Rejection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current drone detection systems face challenges in accurately identifying frequency hopping parameters from noisy time-frequency samples, especially in multi-target scenarios, due to high implementation complexity and sensitivity to errors, which hinders real-time detection and mitigation capabilities.

Innovation Solution

The implementation of a frequency hopping parameter estimation method based on the random sample consensus (RANSAC) algorithm, which estimates parameters with high accuracy using a small set of samples, effectively classifying inliers and outliers to identify drones, even under conditions of gross errors and timing errors, and supports real-time operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If traditional frequency hopping parameter estimation methods are used, then detection accuracy may be maintained, but implementation complexity increases and sensitivity to errors worsens

Engineering Contradiction:
Improveimplementation complexityVSAvoidparameter estimation accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent segments the frequency hopping signal analysis into distinct parameter estimation tasks (frequency, timing, code rate) and processes them sequentially using RANSAC iterations. Each iteration focuses on estimating a subset of parameters from randomly selected samples, breaking down the complex estimation problem into manageable segments that reduce overall implementation complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies partial action by using a small random subset of samples rather than processing the entire signal dataset. The RANSAC algorithm iteratively selects random subsets of frequency-time samples to estimate parameters, performing only the necessary computations on these partial sets, which significantly reduces computational complexity while maintaining robustness through multiple iterations.

Inventive Principle:
Principle #16Partial or excessive action

2Measurement precision

If more samples are used for parameter estimation, then accuracy improves, but processing time increases and real-time capability deteriorates

Engineering Contradiction:
Improveparameter estimation accuracyVSAvoidreal-time detection speed
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent uses partial action by processing only random subsets of samples in each RANSAC iteration rather than the complete dataset. This partial processing approach maintains accuracy through statistical robustness while dramatically reducing processing time, enabling real-time drone detection and parameter estimation.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent implements periodic action through iterative RANSAC cycles that repeatedly sample and estimate parameters. Multiple iterations over different random subsets provide robust accuracy, while the periodic nature of these iterations allows for efficient parallel processing and maintains real-time detection capability through structured repetition.

Inventive Principle:
Principle #19Periodic action

3Reliability

If robust error tolerance is implemented, then reliability improves, but computational complexity increases

Engineering Contradiction:
Improveerror toleranceVSAvoidcomputational complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by pre-selecting random subsets of samples before parameter estimation. The RANSAC framework prepares multiple random sample sets in advance, and the robust error tolerance is built into this preliminary sampling structure. This preliminary organization reduces the complexity of handling errors during the actual estimation process.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements self-service through the iterative RANSAC process that automatically identifies and rejects outlier samples. The algorithm serves itself by using the majority of consistent samples to estimate parameters and automatically filtering out erroneous measurements, providing robust error tolerance without requiring complex external error correction mechanisms.

Inventive Principle:
Principle #25Self-service

4Measurement precision

If comprehensive signal processing is performed, then detection accuracy improves, but energy consumption increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidpower efficiency
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent reduces energy consumption by performing partial signal processing only on randomly selected sample subsets rather than processing the entire received signal. The RANSAC approach processes only the necessary minimum samples required for robust parameter estimation, significantly reducing computational load and energy consumption while maintaining detection accuracy.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentUS11552674B2Systems and methods for detecting, monitoring, and mitigating the presence of a drone using frequency hopping
Publication Date: 2023.01.10 SKYSAFE INC
  • US11552674B2 patent drawing
  • US11552674B2 patent drawing
  • US11552674B2 patent drawing

AI summary

Systems and methods for detecting, monitoring, and mitigating the presence of a drone are provided herein. In one aspect, a system for detecting presence of a one or more drones includes a radio-frequency (RF) receiver configured to receive an RF signal transmitted between a drone and a controller. The system can further include a processor and a computer-readable memory in communication with the processor and having stored thereon computer-executable instructions to cause the at least one processor to receive a set of samples from the RF receiver for a time interval, the set of samples comprising samples of the first RF signal, obtain a parameter model of the first frequency hopping parameters, and fit the parameter model to the set of samples.