Radar interference detection

1. A data processing device for detecting interference in frequency modulated continuous wave, FMCW, radar signals received by a radar receiver of a radar system, wherein the data processing device is configured to:

obtain a plurality of samples forming a beat signal;

determine a magnitude of each sample;

group the plurality of samples into a plurality of subsets wherein each subset corresponds to a given time segment of the beat signal;

determine a maximum magnitude of each subset;

extract an n th lowest maximum magnitude of the plurality of subsets to determine an adaptive threshold;

apply the adaptive threshold to each sample of the plurality of samples to generate a mask, wherein if the magnitude of a sample is higher than the adaptive threshold the mask has a first value for that sample and if the magnitude of the sample is lower than the adaptive threshold the mask has a second value for that sample; and

apply the mask to the beat signal to remove any samples detected as comprising interference,

wherein the first value is indicative of a sample comprising interference and the second value is indicative of a sample without interference.

2. The data processing device of claim 1 , further configured to multiply the extracted n th lowest maximum magnitude by an upscaling factor to determine the adaptive threshold.

3. The data processing device of claim 1 , wherein the n th lowest maximum magnitude is the 3 rd lowest maximum magnitude, or the 2 nd lowest maximum magnitude, or the lowest maximum magnitude.

4. The data processing device of claim 1 , wherein prior to determining the magnitude of each sample, the data processing device is configured to:

apply a high-pass filter to each sample of the plurality of samples.

5. The data processing device of claim 1 , further configured to:

apply a moving average filter followed by a fixed threshold to the mask.

6. The data processing device of claim 1 , wherein the plurality of subsets is a first plurality of subsets, the adaptive threshold is a first adaptive threshold and the mask is a first mask, and the data processing device is further configured to:

apply a high-pass filter to each sample of the plurality of samples;

determine the modulus of each high-pass filtered sample to produce a plurality of modulus high-pass filtered beat samples;

group the plurality of modulus high-pass filtered beat samples into a second plurality of subsets, wherein each subset of the second plurality of subsets corresponds to a given time segment of the modulus of the high-pass filtered beat signal;

determine a maximum magnitude of each subset of the second plurality of subsets;

extract an n th lowest maximum magnitude of the second plurality of subsets to determine a second adaptive threshold;

apply the second adaptive threshold to each modulus high-pass filtered beat sample of the plurality of modulus high-pass filtered beat samples to generate a second mask, wherein if the magnitude of a sample is higher than the second adaptive threshold the second mask has a first value for that sample and if the magnitude of the sample is lower than the second adaptive threshold the second mask has a second value for that portion; and

multiply the first mask and the second mask together to generate a combined mask.

7. The data processing device of claim 6 , further configured to:

apply a moving average filter followed by a fixed threshold to at least one of the first mask and the second mask.

8. The data processing device of claim 1 , further configured to:

determine the number of first values in the mask; and

in response to determining that the number of first values exceeds a predetermined limit, set an interference flag.

9. The data processing device of claim 1 , further configured to:

generate a plurality of masks or a plurality of combined masks, each mask or combined mask associated with a respective beat signal; and

aggregate the plurality of masks or the plurality of combined masks to form a first one-dimensional vector and a second one-dimensional vector,

wherein each variable in the first one-dimensional vector is a summation of the number of first values in the plurality of masks or the plurality of combined masks in the time dimension, and

wherein each variable in the second one-dimensional vector is a summation of the number of first values in the plurality of masks or the plurality of combined masks in the frequency dimension.

10. The data processing device of claim 9 , further configured to:

set an interference flag if a variable in either the first one-dimensional vector or the second one-dimensional vector exceeds a predetermined limit.

11. A package including an integrated circuit, wherein the integrated circuit is configured to provide the data processing device of claim 1 .

12. A frequency modulated continuous wave, FMCW, radar system including the data processing device of claim 1 .

13. A method of detecting interference in a frequency modulated continuous wave, FMCW, radar system, the method comprising:

obtaining a plurality of samples forming a beat signal;

determining a magnitude of each sample;

grouping the plurality of samples into a plurality of subsets, wherein each subset corresponds to a given time segment of the beat signal;

determining a maximum magnitude of each subset;

extracting an n th lowest maximum magnitude of the plurality of subsets to determine an adaptive threshold;

applying the adaptive threshold to each sample of the plurality of samples to generate a mask, wherein if the magnitude of a sample is higher than the adaptive threshold the mask has a first value for that sample and if the magnitude of the sample is lower than the adaptive threshold the mask has a second value for that sample; and

further comprising applying the mask to the beat signal to remove any samples detected as comprising interference,

wherein the first value is indicative of a sample comprising interference and the second value is indicative of a sample without interference.

14. The method of claim 13 , wherein the plurality of subsets is a first plurality of subsets, the adaptive threshold is a first adaptive threshold and the mask is a first mask, and the method further comprises:

applying a high-pass filter to each sample of the plurality of samples;

determining the modulus of each high-pass filtered sample to produce a plurality of modulus high-pass filtered beat samples;

grouping the plurality of modulus high-pass filtered beat samples into a second plurality of subsets, wherein each subset of the second plurality of subsets corresponds to a given time segment of the modulus of the high-pass filtered beat signal;

determining a maximum magnitude of each subset of the second plurality of subsets;

extracting an nth lowest maximum magnitude of the second plurality of subsets to determine a second adaptive threshold;

applying the second adaptive threshold to each modulus high-pass filtered beat sample of the plurality of modulus high-pass filtered beat samples to generate a second mask, wherein if the magnitude of a sample is higher than the second adaptive threshold the second mask has a first value for that sample and if the magnitude of the sample is lower than the second adaptive threshold the second mask has a second value for that portion; and

multiplying the first mask and the second mask together to generate a combined mask.

15. The method of claim 14 , further comprising applying a moving average filter followed by a fixed threshold to at least one of the first mask and the second mask.

16. The method of claim 13 , further comprising multiplying the extracted n th lowest maximum magnitude by an upscaling factor to determine the adaptive threshold.

17. The method of claim 13 , wherein the n th lowest maximum magnitude is the 3 rd lowest maximum magnitude, or the 2 nd lowest maximum magnitude, or the lowest maximum magnitude.

18. The method of claim 13 , further comprising:

prior to determining the magnitude of each sample, applying a high-pass filter to each sample of the plurality of samples.

19. A data processing device for detecting interference in frequency modulated continuous wave, FMCW, radar signals received by a radar receiver of a radar system, wherein the data processing device is configured to:

obtain a plurality of samples forming a beat signal;

determine a magnitude of each sample;

group the plurality of samples into a plurality of subsets wherein each subset corresponds to a given time segment of the beat signal;

determine a maximum magnitude of each subset;

extract an n th lowest maximum magnitude of the plurality of subsets to determine an adaptive threshold;

apply the adaptive threshold to each sample of the plurality of samples to generate a mask, wherein if the magnitude of a sample is higher than the adaptive threshold the mask has a first value for that sample and if the magnitude of the sample is lower than the adaptive threshold the mask has a second value for that sample; and

determine the number of first values in the mask; and

in response to determining that the number of first values exceeds a predetermined limit, set an interference flag,

wherein the first value is indicative of a sample comprising interference and the second value is indicative of a sample without interference.