Utilizing a fast Fourier transform to cancel a non-linear phase response of a digital infinite impulse response lowpass filter to facilitate removal of interference from time domain orthogonal frequency-division multiplexing based digital input values

A method, comprising:

• obtaining, by an apparatus, time domain based digital input values corresponding to respective wireless communication channels;
• based on the time domain based digital input values, generating, by the apparatus via a digital infinite impulse response (IIR) lowpass filter comprising a first non-linear phase response, respective groups of discrete time domain based output values comprising non-linear phase distortion corresponding to the first non-linear phase response;
• removing, by the apparatus, cyclic prefix values corresponding to the respective groups of discrete time domain based output values;
• generating, by the apparatus based on the respective groups of discrete time domain based output values using a digital fast Fourier transform, frequency domain based digital output values comprising a second non-linear phase response corresponding to the non-linear phase distortion of the discrete time domain based output values;
• based on the first non-linear phase response of the digital IIR lowpass filter, determining, by the apparatus, respective phase compensation factors for the frequency domain based digital output values to facilitate correction of the second non-linear phase response corresponding to the non-linear distortion of the discrete time domain output values;
• and
• based on the respective phase compensation factors and the frequency domain based digital output values, determining, by the apparatus, complex frequency domain based digital output values comprising a linear phase response that satisfies a defined linearity condition with respect a defined amount of correction of the second non-linear phase response corresponding to the non-linear distortion of the discrete time domain output values.

A non-transitory machine-readable medium comprising instructions that, in response to execution, cause a system comprising a processor to perform operations, the operations comprising:

• in response to receiving orthogonal frequency-division multiplexing (OFDM) analog input values, generating, based on the OFDM analog input values, time domain based OFDM digital input values;
• filtering, via a digital infinite impulse response (IIR) low-pass filter, interference signals from the time domain based OFDM digital input values to obtain time domain based OFDM digital output values, wherein the digital IIR low-pass filter introduces first non-linear phase distortion into the time domain based OFDM digital output values;
• converting, via a digital fast Fourier transform, the time domain based OFDM digital output values into frequency domain based OFDM digital output values comprising second non-linear phase distortion corresponding to the first non-linear phase distortion that has been introduced via the digital IIR low-pass filter;
• and
• based on the first non-linear phase distortion that has been introduced via the digital IIR low-pass filter, correcting the second non-linear phase distortion to obtain a linear phase response of the frequency domain based OFDM digital output values, the linear phase response represented by a defined amount of phase correction of the second non-linear phase distortion.