Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cognitive MAC Protocols Using Memory for Distributed Spectrum Sharing
  Under Limited Spectrum Sensing   The main challenges of cognitive radio include spectrum sensing at the
physical (PHY) layer to detect the activity of primary users and spectrum
sharing at the medium access control (MAC) layer to coordinate access among
coexisting secondary users. In this paper, we consider a cognitive radio
network in which a primary user shares a channel with secondary users that
cannot distinguish the signals of the primary user from those of a secondary
user. We propose a class of distributed cognitive MAC protocols to achieve
efficient spectrum sharing among the secondary users while protecting the
primary user from potential interference by the secondary users. By using a MAC
protocol with one-slot memory, we can obtain high channel utilization by the
secondary users while limiting interference to the primary user at a low level.
The results of this paper suggest the possibility of utilizing MAC design in
cognitive radio networks to overcome limitations in spectrum sensing at the PHY
layer as well as to achieve spectrum sharing at the MAC layer.

27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int