  In this paper we propose a new method for training neural networks (NNs) for
frequency modulated continuous wave (FMCW) radar mutual interference
mitigation. Instead of training NNs to regress from interfered to clean radar
signals as in previous work, we train NNs directly on object detection maps. We
do so by performing a continuous relaxation of the cell-averaging constant
false alarm rate (CA-CFAR) peak detector, which is a well-established algorithm
for object detection using radar. With this new training objective we are able
to increase object detection performance by a large margin. Furthermore, we
introduce separable convolution kernels to strongly reduce the number of
parameters and computational complexity of convolutional NN architectures for
radar applications. We validate our contributions with experiments on
real-world measurement data and compare them against signal processing
interference mitigation methods.
