Capacity gain through power enhancement in multi-radio multi-channel wireless networks

The main focus of this paper is to show theoretically that power is a crucial factor in multi-radio multi-channel (MR-MC) wireless networks and hence by judiciously leveraging the power, one can realize a considerable gain on the capacity for MR-MC wireless networks. Such a capacity gain through power enhancement is revealed by our new insights of a co-channel enlarging effect. In particular, when the number of available channels (c) in a network is larger than that necessary for enabling the maximum set of simultaneous transmissions (c̃), allocating transmissions to those additional c-c̃ channels could enlarge the distance between the co-channel transmissions; the larger co-channel distance then allows a higher transmission power for higher link capacity. The finding of this paper specifically indicate that by exploiting the co-channel enlarging effect with power, one can realize the following gain on the capacity for MR-MC wireless networks: (i) In the channel-constraint region (c̃ <; c <; nφ/2), if each node augments its power from the minimum P_min to P_min c/c̃^α/2, then a gain of Θ(log(c/c̃)^α/2) is achieved; (ii) In the power-constraint region (c ≥ nφ/2), if each node sends at the maximum power level, P_max = P_min.n^K or P_min.2nφ/2, depending on the power availability at a node, then a gain of Θ(log n) or Θ(n) is achieved, respectively.