No abstract

No abstract

Next generation networks are expected to be ultradense and aim to explore spectrum sharing paradigm that allows users to communicate in licensed, shared as well as unlicensed spectrum. Such ultra-dense networks will incur significant signaling load at base stations leading to a negative effect on spectrum and energy efficiency. To minimize signaling overhead, an adhoc approach is being considered for users communicating in the unlicensed and shared spectrums. For such users, decisions need to be completely decentralized as: 1) No communication between users and signaling from the base station is possible which necessitates independent channel selection at each user. A collision occurs when multiple users transmit simultaneously on the same channel, 2) Channel qualities may be heterogeneous, i.e., they are not same across all users, and moreover, are unknown, and 3) The network could be dynamic where users can enter or leave anytime. We develop a multi-armed bandit based distributed algorithm for static networks and extend it for the dynamic networks. The algorithms aim to achieve stable orthogonal allocation (SOC) in finite time and meet the above three constraints with two novel characteristics: 1) Low complexity narrowband radio compared to wideband radio in existing works, and 2) Epoch-less approach for dynamic networks. We establish convergence of our algorithms to SOC and validate via extensive simulation experiments.Index Terms-Multi-player multi-armed bandit, ad-hoc networks, dynamic networks, distributed learning.

Wireless transmissions are inherently broadcast and are vulnerable to jamming attacks. Frequency hopping (FH) and transmission rate adaptation (RA) have been used to mitigate jamming. However, recent works have shown that using either FH or RA (but not both) is inefficient against smart jamming. In this paper, we propose mitigating jamming by jointly optimizing the FH and RA techniques. We consider a power constrained "reactive-sweep" jammer who aims at degrading the goodput of a wireless link. We model the interaction between the legitimate transmitter and jammer as a zero-sum Markov game, and derive the optimal defense strategy. Numerical investigations show that the new scheme improves the average goodput and provides better jamming resiliency.

No abstract