Doppler-Range Interference Mitigation in DDMA Radar Chirps
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Solution Overview
Problem
Doppler division multiple-access (DDMA) systems face interference issues in Doppler-range representations due to overlapping chirps from multiple transmitters, which can impair the performance of radar systems.
Innovation Solution
Implement programmable circuitry to reconstruct corrupted samples by determining a reconstructed chirp for a frame of chirps, performing a range Fourier transform (FT) representation, and generating a second Doppler-range representation as an element-wise minimum between the first and third representations, effectively mitigating interference along both the range and Doppler dimensions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple transmitters are enabled simultaneously in DDMA systems, then the productivity of radar systems is improved, but interference in Doppler-range representations occurs
Solution Approach 1:
The patent extracts and removes corrupted samples from the chirp signals before processing. By identifying and taking out the harmful corrupted portions that cause interference in Doppler-range representations, the system maintains multi-transmitter productivity while eliminating the specific interference problem
Solution Approach 2:
The patent introduces an intermediary processing step between signal reception and Doppler-range representation generation. This intermediary stage reconstructs corrupted samples using adjacent samples as mediators, preventing the interference from propagating to the final representation while preserving the benefits of simultaneous multi-transmitter operation
2Device complexity
If corrupted samples are not reconstructed, then the device complexity is reduced, but measurement precision of radar targets deteriorates
Solution Approach 1:
The patent performs preliminary reconstruction of corrupted samples before generating Doppler-range representations. By taking preliminary action to repair corrupted data points using adjacent samples, the system ensures measurement precision is maintained without requiring complex post-processing or advanced reconstruction algorithms
Solution Approach 2:
The patent changes the parameter values of corrupted samples by replacing them with reconstructed values derived from adjacent samples. This parameter substitution approach maintains measurement precision while avoiding the complexity of sophisticated reconstruction techniques, as it simply replaces problematic parameter values with corrected ones
Data Source
AI summary
An example apparatus includes interface circuitry to receive digital samples representative of a frame of chirps. The apparatus includes programmable circuitry, which may be programmed by instructions, to: for a range Fourier transform (FT) representation of the frame of chirps, determine a reconstructed chirp for a chirp of the frame of chirps that includes a corrupted sample; determine a first Doppler-range representation of the frame of chirps based on the range FT representation, the range FT representation including the reconstructed chirp; and determine a second Doppler-range representation as an element-wise minimum between the first Doppler-range representation and a third Doppler-range representation of the frame of chirps, the third Doppler-range representation based on the digital samples, the digital samples including a reconstructed sample substituted for the corrupted sample of the chirp. Other examples are described.