Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Deep Learning-Based Blind Multiple User Detection for Grant-free SCMA
  and MUSA Systems   Grant-free random access and uplink non-orthogonal multiple access (NOMA) are
techniques to increase the overload factor and reduce transmission latency with
signaling overhead in massive machine-type communications (mMTC). Sparse code
multiple access (SCMA) and Multi-user shared access (MUSA) are introduced as
advanced code domain NOMA schemes. In grant-free NOMA, machine-type devices
(MTD) transmit information to the base station (BS) without a grant, creating a
challenging task for the BS to identify the active MTD among all potential
active devices. In this paper, a novel deep neural network (DNN)-based
multi-user detection (MUD) scheme for the grant-free SCMA and MUSA system in an
mMTC uplink framework is proposed to jointly identify the received signal's
sparsity and the active MTDs in the absence of channel state information. The
proposed scheme learns the correlation between the received signal and the
multi-dimensional codebook for SCMA and spreading sequences for MUSA schemes
and is able to identify the active MTDs from the received signal without any
prior knowledge of the device sparsity level. The application of the proposed
MUD scheme is further investigated in an indoor factory setting using four
different mmWave channels. Numerical results show that when the number of
active MTDs in the system is large, DNN-MUD has a significantly higher
probability of detection compared to existing approaches over the
signal-to-noise ratio range of interest.

11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga