  We present a novel autoencoder-based approach for designing codes that
provide unequal error protection (UEP) capabilities. The proposed design is
based on a generalization of an autoencoder loss function that accommodates
both message-wise and bit-wise UEP scenarios. In both scenarios, the
generalized loss function can be adjusted using an associated weight vector to
trade off error probabilities corresponding to different importance classes.
For message-wise UEP, we compare the proposed autoencoder-based UEP codes with
a union of random coset codes. For bit-wise UEP, the proposed codes are
compared with UEP rateless spinal codes and the superposition of random
Gaussian codes. In all cases, the autoencoder-based codes show superior
performance while providing design simplicity and flexibility in trading off
error protection among different importance classes.
