Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: ML and MAP Device Activity Detections for Grant-Free Massive Access in
  Multi-Cell Networks   Device activity detection is one main challenge in grant-free massive access,
which is recently proposed to support massive machine-type communications
(mMTC). Existing solutions for device activity detection fail to consider
inter-cell interference generated by massive IoT devices or important prior
information on device activities and inter-cell interference. In this paper,
given different numbers of observations and network parameters, we consider
both non-cooperative device activity detection and cooperative device activity
detection in a multi-cell network, consisting of many access points (APs) and
IoT devices. Under each activity detection mechanism, we consider the joint
maximum likelihood (ML) estimation and joint maximum a posterior probability
(MAP) estimation of both device activities and interference powers, utilizing
tools from probability, stochastic geometry, and optimization. Each estimation
problem is a challenging non-convex problem, and a coordinate descent algorithm
is proposed to obtain a stationary point. Each proposed joint ML estimation
extends the existing one for a single-cell network by considering the
estimation of interference powers, together with the estimation of device
activities. Each proposed joint MAP estimation further enhances the
corresponding joint ML estimation by exploiting prior distributions of device
activities and interference powers. The proposed joint ML estimation and joint
MAP estimation under cooperative detection outperform the respective ones under
non-cooperative detection at the costs of increasing backhaul burden, knowledge
of network parameters, and computational complexities.

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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: cond-mat
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg