Frequency Hopping Receiver Noise-Based Channel Selection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Frequency hopping communication systems face challenges in avoiding signal jamming due to high noise levels and interfering signals, which affect the receiver's ability to detect the transmitted signal effectively.

Innovation Solution

The method involves measuring noise levels on permissible channels, selecting a dwell channel with the lowest noise level based on historical data, and tuning the receiver to this channel during the search state to synchronize with the transmitter, while also considering dynamic noise estimation and biasing techniques to improve signal detection probability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the receiver uses a fixed frequency channel for signal acquisition, then the receiver can maintain stable operation, but the receiver is vulnerable to signal jamming and interference on that fixed channel

Engineering Contradiction:
Improvesignal detection reliabilityVSAvoidjamming and interference
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The system dynamically selects frequency channels based on real-time noise level measurements rather than using a fixed channel. The receiver measures noise levels on multiple permissible channels and selects the channel with the lowest noise level for signal acquisition, making the system adaptable to changing interference conditions

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the operating frequency parameter by selecting different frequency channels based on measured noise levels. The receiver measures noise on each channel and selects the channel with the most favorable noise characteristics, thereby changing the frequency parameter to avoid jamming and interference

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the receiver measures noise levels on all permissible channels before selecting a dwell channel, then the receiver can avoid jammed channels, but the time required for channel selection and synchronization increases

Engineering Contradiction:
Improvechannel selection accuracyVSAvoidsynchronization time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system performs noise level measurements on multiple channels but selects the channel with the lowest noise level without requiring exhaustive search of all possible channels. The receiver measures noise on permissible channels and selects the best one found, balancing measurement thoroughness with time constraints

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The system performs preliminary noise level measurements on permissible channels before final channel selection. By measuring noise levels in advance on multiple channels and selecting the best one beforehand, the system prepares the optimal channel for signal acquisition, reducing the time needed during actual synchronization

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP2005598B1Signal jamming avoidance method for a frequency hopping communication system
Publication Date: 2013.05.08 HARRIS CORP
  • EP2005598B1 patent drawingFigure 1
  • EP2005598B1 patent drawingFigure 2
  • EP2005598B1 patent drawingFigure 3

AI summary

To avoid signal jamming, a method is provided for selecting a dwell channel on a receiver in a frequency hopping communication system. The method includes: measuring a noise level on channels over which a data signal is received at the receiver; selecting a dwell channel based on the estimated noise levels, where the dwell channel having the lowest noise level amongst a group of permissible channels over which to acquire a signal from a transmitter; and tuning the receiver to the selected dwell channel during a search state in which the receiver attempts to synchronize with a transmitter.