  To achieve a reliable communication with short data blocks, we propose a
novel decoding strategy for Kronecker-structured constant modulus signals that
provides low bit error ratios (BERs) especially in the low energy per bit to
noise power spectral density ratio $(E_b/N_0)$. The encoder exploits the fact
that any M-PSK constellation can be factorized as Kronecker products of lower
or equal order PSK constellation sets. A construction of two types of schemes
is first derived. For such Kronecker-structured schemes, a conceptually simple
decoding algorithm is proposed, referred to as Kronecker-RoD (rank-one
detector). The decoder is based on a rank-one approximation of the "tensorized"
received data block, has a built-in noise rejection capability and a smaller
implementation complexity than state-of-the-art detectors. Compared with
convolutional codes with hard and soft Viterbi decoding, Kronecker-RoD
outperforms the latter in BER performance at same spectral efficiency.
