Sparse Superimposed Codes for Vehicular Communications with Low-Resolution ADCs

Sparse superimposed codes (SSC) are a promising short-packet transmission scheme in next generation communication systems. This paper presents a quantized SSC (Q-SSC) based short-packet scheme for sensing data transmission in vehicular communication systems with low-resolution analog-to-digital converters. The core idea behind Q-SSC is to transmit short-packet data by mapping information bits to multiple superimposed sparse vectors. The superimposed sparse vectors are then mapped onto subcarriers for transmission after pseudo-random spreading. At the receiver, the decoding process is transformed into a sparse signal recovery problem, and a conjugate gradient hard thresholding pursuit algorithm is proposed for accurate decoding from quantized measurements. Extensive simulation results show that the proposed Q-SSC scheme outperforms existing schemes in terms of block error rate over doubly selective channels.