Frequency Domain Multi-Channel Equalizer for Interference Rejection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current multichannel equalization methods for radio communications, particularly in military radiocommunications, face challenges in efficiently handling interference and multipath propagation in complex environments, leading to suboptimal performance and high computational complexity.
Innovation Solution
A method for anti-scrambled multi-channel equalization in the frequency domain is proposed, which involves calculating the noise and interference correlation matrix using specific formulas and applying a spatial filter to optimize signal reception, reducing computational complexity while maintaining interference rejection and path exploitation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If current multichannel equalization methods are used to handle interference and multipath propagation, then signal reception performance is improved, but computational complexity increases significantly
Solution Approach 1:
The patent transforms the equalization problem from the time domain to the frequency domain by applying FFT (Fast Fourier Transform). This parameter change in the domain of processing allows complex convolution operations to be replaced by simple multiplication operations, significantly reducing computational complexity while maintaining equalization performance in multipath environments
Solution Approach 2:
The patent replaces traditional time-domain equalization algorithms (such as LMS, RLS) with a frequency-domain approach using FFT-based processing. This substitution changes the fundamental mechanism from iterative time-domain adaptation to direct frequency-domain transformation, reducing the number of computations required while achieving the same interference and multipath mitigation effects
2Object-affected harmful factors
If traditional time-domain equalization methods are used, then interference rejection is achieved, but computational power requirements are high
Solution Approach 1:
The patent changes the processing domain from time to frequency using FFT, which transforms complex time-domain filtering operations into simpler frequency-domain multiplications. This parameter change reduces the computational power required while maintaining the ability to reject interference and suppress multipath effects through frequency-selective processing
3Measurement precision
If learning sequences are inserted periodically to monitor channel variations, then channel estimation accuracy is improved, but transmission efficiency decreases
Solution Approach 1:
The patent uses partial learning sequences (pilot symbols) inserted periodically in the transmission stream to perform channel estimation only where necessary. This partial action approach balances the need for accurate channel monitoring with the requirement to maintain high transmission efficiency by minimizing the overhead associated with training sequences
Data Source
Figure 1a~1b
Figure 2a~2b
Figure 2c~2d
AI summary
The invention relates to a method for receiving and anti-interference equalizing a signal comprising at least one training sequence and at least one useful data sequence, as well as to the receiver implementing the method. It includes the steps of: • receiving the signal on a plurality of channels of the receiver, transposition and discretization into a discretized multichannel signal, • synchronization of the multichannel signal, • calculation (150) of an impulse response of the multichannel channel ĥ(f) and of a correlation matrix R̂ of noise and interference, from at least one part corresponding to a learning sequence of said synchronized multichannel signal, • transposition in the frequency domain (231) of at least one part corresponding to a useful data sequence of the synchronized multichannel signal, and filtering (232) by the vector w(f), with wf=R^−1h^f1+h^fHR^−1h^f, • transposition (233) in the time domain of the filtered signal.