The first of two Best Paper Awards from INISCom 2015

The First edition of the International Conference on Industrial Networks and Intelligent Systems (INISCom 2015), which took place in Tokyo, Japan on March 2–4, 2015, awarded two studies with the Best Paper Award.

One of them has been written by Shashi Shah and Somsak Kittipiyakul, two researchers from the Thammasat University (Thailand).

The research, entitled “Best-Response Distributed Subchannel Selection for Minimizing Interference in Femtocell Networks” studies the problem of distributed subchannel selection of non-cooperative OFDMA femtocells in two-tiered macro-femto networks. Using a physical channel model, the researchers consider a decentralized subchannel allocation of femtocell networks and a total throughput objective, which is the total throughput of uplink macro users and femto users. They assume a time-slotted system, a time-invariant channel model (no fading), each user knows the signal-to-interference-plus-noise ratio (SINR) of all candidate subchannels, and subchannel re-selection happens only at the beginning of each timeslot. They study the performance of a best response strategy when each user chooses to transmit in the lowest-SINR subchannel, i.e., each user’s action is a best-response to the current SINRs in the subchannels. If all users update their actions every timeslot (i.e., all users make simultaneous moves), an oscillation can occur and result in a suboptimal performance.

What are the outcomes? Researchers proposed a decentralized algorithm for sub-channel allocation by femtocell users in macro works. They found that each user regularly sensed the SINRs on all sub-channels and selected the best sub-channel with some selection probability. The sub-channel allocation for small value of the selection probability reacheed the steady state faster and at a higher steady with oscillations is seen when all users make a simultaneous channel selection.

You can read the whole research here.