Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Joint Channel Estimation and Device Activity Detection in Heterogeneous
  Networks   Internet of Things (IoT) has triggered a rapid increase in the number of
connected devices and new use cases of wireless communications. To meet the new
demands, the fifth generation (5G) of wireless communication systems features
native machine type communication (MTC) services in addition to traditional
human type communication (HTC) services. Some of the main challenges are the
heterogeneous requirements and the sporadic traffic of massive MTC (mMTC),
which makes the orthogonal allocation of resources infeasible. To overcome this
problem, grant free non-orthogonal multiple access schemes have been proposed
alongside with sparse signal recovery algorithms. While most of the related
works have considered only homogeneous networks, we focus on a scenario where
an enhanced mobile broadband (eMBB) device and multiple MTC devices share the
same radio resources. We exploit the approximate message passing (AMP)
algorithm for joint device activity detection and channel estimation of MTC
devices in the presence of interference from eMBB, and evaluate the system
performance in terms of receiver operating characteristics (ROC) and channel
estimation errors. Moreover, we also propose two new pilot sequence generation
strategies which improve the detection capabilities of the MTC receiver without
affecting the eMBB service.

14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph