Efficient and rational spectrum utilization in opportunistic OFDMA networks with imperfect CSI: a utility‐based top‐down approach

Abstract

In this paper, we consider the Orthogonal Frequency Division Multiple Access (OFDMA)‐based Opportunistic Radio (OR) networks, in which the nodes are able to adopt a subset of subcarriers (SCs) available in the considered network area, as well as the transmission rate and power associated with these SCs either for their uplink or downlink transmission. The idea of our top‐down approach to the efficient and rational spectrum utilization is to allow each node to first optimize the resources acquisition at OSI‐layer 2 (top), where the competition of nodes for available common resources is observed, and then to autonomously optimize the transmission parameters accounting for the radio channel conditions at the physical (down) layer. We assume that the nodes act independently based on their local channel quality information, which contains an error. In these optimization tasks, the efficiency and rationality mechanisms have been introduced in the objective (utility) functions, which reflect the throughput achieved, the network potential to serve multiple nodes, as well as pricing of resources and the power economy. Copyright © 2010 John Wiley & Sons, Ltd.

Dynamic decentralised algorithms for cognitive radio relay networks with multiple primary and secondary users utilising matching theory

“…These papers include combining different parameters, such as price, delay, signal-to-interference and noise ratio, power, rate, error performance, into a single number. Specifically in cognitive radio, the utility function have been used in [1,4,9,[39][40][41].…”

Optimal Pricing of Spectrum Resources in Wireless Opportunistic Access

“…In [17] we have proposed a noncooperative completeinformation two-dimensional game, where the payoffs of both players (player k and the NCC at the kth game stage) reflect their decisions. In such a case, being the alternative to the framework discussed above, the strategy space of the considered kth player is the same (consists of possible number of the orthogonal channels the player acquires).…”

“…In such a case, the integrations in (5), (10), (15), (16), (20), and (21) should be replaced by summations, and the value of b k and b * k should be approximated by the discrete number of channels i k of a particular bandwidth Δ f (with a particular resolution). Moreover, as shown in [17], there exists the NE for the discrete orthogonal channels (like in OFDMA). Below, for such a case of the available bandwidth discretization, we present the optimal tax-ratesearching algorithm with reduced complexity tracing the instantaneous variations of the network-objective function η ST around its maximal value.…”

“…In our earlier work [17], we have presented distributed SCs allocation interference-free method in a network of the OFDMA-based opportunistic radios. It aimed at rational and efficient spectrum utilization in both the uplink or downlink transmission.…”