90 research outputs found
Sum-Capacity of Ergodic Fading Interference and Compound Multiaccess Channels
The problem of resource allocation is studied for two-sender two-receiver
fading Gaussian interference channels (IFCs) and compound multiaccess channels
(C-MACs). The senders in an IFC communicate with their own receiver (unicast)
while those in a C-MAC communicate with both receivers (multicast). The
instantaneous fading state between every transmit-receive pair in this network
is assumed to be known at all transmitters and receivers. Under an average
power constraint at each source, the sum-capacity of the C-MAC and the power
policy that achieves this capacity is developed. The conditions defining the
classes of strong and very strong ergodic IFCs are presented and the multicast
sum-capacity is shown to be tight for both classes.Comment: Proceedings of the 2008 IEEE International Symposium on Information
Theory, Toronto, ON, Canada, July 6 - 11, 200
Coalitions in Cooperative Wireless Networks
Cooperation between rational users in wireless networks is studied using
coalitional game theory. Using the rate achieved by a user as its utility, it
is shown that the stable coalition structure, i.e., set of coalitions from
which users have no incentives to defect, depends on the manner in which the
rate gains are apportioned among the cooperating users. Specifically, the
stability of the grand coalition (GC), i.e., the coalition of all users, is
studied. Transmitter and receiver cooperation in an interference channel (IC)
are studied as illustrative cooperative models to determine the stable
coalitions for both flexible (transferable) and fixed (non-transferable)
apportioning schemes. It is shown that the stable sum-rate optimal coalition
when only receivers cooperate by jointly decoding (transferable) is the GC. The
stability of the GC depends on the detector when receivers cooperate using
linear multiuser detectors (non-transferable). Transmitter cooperation is
studied assuming that all receivers cooperate perfectly and that users outside
a coalition act as jammers. The stability of the GC is studied for both the
case of perfectly cooperating transmitters (transferrable) and under a partial
decode-and-forward strategy (non-transferable). In both cases, the stability is
shown to depend on the channel gains and the transmitter jamming strengths.Comment: To appear in the IEEE Journal on Selected Areas in Communication,
Special Issue on Game Theory in Communication Systems, 200
False Data Injection Attacks on Phasor Measurements That Bypass Low-rank Decomposition
This paper studies the vulnerability of phasor measurement units (PMUs) to
false data injection (FDI) attacks. Prior work demonstrated that unobservable
FDI attacks that can bypass traditional bad data detectors based on measurement
residuals can be identified by detector based on low-rank decomposition (LD).
In this work, a class of more sophisticated FDI attacks that captures the
temporal correlation of PMU data is introduced. Such attacks are designed with
a convex optimization problem and can always bypass the LD detector. The
vulnerability of this attack model is illustrated on both the IEEE 24-bus RTS
and the IEEE 118-bus systems.Comment: 6 pages, 4 figures, submitted to 2017 IEEE International Conference
on Smart Grid Communications (SmartGridComm
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