Adaptive Digital Filtering for FHSS Interference Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for mitigating interference in wireless communications, particularly in Frequency Hopping Spread Spectrum (FHSS) and multipath propagation scenarios, require significant computational resources due to the need for multiple adaptive filters and digital down converters, leading to high resource utilization.
Innovation Solution
The method optimizes the use of computational resources by sharing them between multiple receive frequencies and multipath copies, allowing a single weight generator to generate weights for multiple frequencies and using a single scrubber for each frequency, reducing the number of required weight generators and digital down converters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate adaptive filters and digital down converters are dedicated to each receive frequency and multipath copy, then interference suppression performance is improved, but computational resource utilization increases
Solution Approach 1:
The patent merges multiple separate adaptive filters into a single shared adaptive filter that processes multiple receive frequencies and multipath copies simultaneously. The digital down converters are also consolidated to share computational resources across different frequency channels, reducing the total number of separate processing units while maintaining interference suppression capability through centralized weight generation and filtering.
Solution Approach 2:
The adaptive filter is designed to perform multiple functions by generating a single set of weights that are applied across multiple receive frequencies and multipath copies. The digital down converters are configured to serve multiple frequency channels, making them universal components that handle different signal paths without requiring dedicated units for each frequency or path.
2Measurement precision
If multiple weight generators are used for multiple frequencies, then filtering accuracy is improved, but computational resource requirements increase
Solution Approach 1:
A single weight generator is designed to produce filter weights that are universally applicable across multiple receive frequencies and multipath copies. The generated weights are shared by all frequency channels and path combinations, eliminating the need for multiple separate weight generators while maintaining filtering accuracy through centralized optimization of the weight set.
Solution Approach 2:
The patent combines multiple weight generation functions into a single unified weight generator that serves all receive frequencies and multipath copies. By merging these functions, the system reduces the total computational burden of generating separate weight sets for each frequency and path, while the shared weights ensure consistent filtering performance across all channels.
3Productivity
If multiple digital down converters are deployed for multiple frequencies and multipath copies, then signal processing capability is improved, but device complexity increases
Solution Approach 1:
The patent merges multiple digital down converter functions into a smaller number of shared converters that serve multiple frequency channels and multipath copies. By consolidating these converters, the system reduces the total number of separate processing units while maintaining the ability to process multiple signals simultaneously through time-division or frequency-division multiplexing of the shared converters.
Solution Approach 2:
The digital down converters are designed as universal components capable of processing multiple frequency channels and multipath copies. Each converter is configured to handle different signal paths and frequency ranges, making them multi-functional units that replace multiple dedicated converters while preserving signal processing capability across all channels.
Data Source
AI summary
A method of mitigating interference in a received wireless signal by adaptive digital filtering efficiently deploys computational resources by using at least one of a DDC, weight generator, and scrubber to perform calculations necessary to generate a plurality of output streams. Embodiments transition a weight generator and scrubber between receiver frequencies according to a known frequency hopping pattern of an FHSS transmission. Other embodiments dedicate scrubbers to receiver frequencies while transitioning a weigh generator between the frequencies to generate sets of weights that can be persistently used by the scrubbers. Embodiments generate sets of weights according to one received multipath signal copy, and then apply the generated weights to filter additional multipath copes received at the same frequency. Various embodiments dedicate a DDC to each receive frequency to form a bank of down-converted outputs, from among which each weigh generator can select primary and reference inputs.