Location-Based Optimum Relay Selection in Random Spatial Networks

Abstract

This paper investigates the location-based relay selection problem, where the source node chooses its relay from a set of spatially deployed decode-and-forward relays. The advantages of location-based relay selection are the elimination of excessive relay switching rate and the feedback reduction avoiding the requirement of having full channel state information at the source node. For a homogeneous Poisson point process of candidate relays, we first derive the distribution for the distance of the relay (relative to the source and destination nodes) selected by the optimum location-based relay selection policy. This result is independent of the functional form of the path-loss function as long as it is a non-increasing function of the transmitter-receiver separation. By utilizing the derived optimum relay distance distribution, we then obtain analytical expressions for the average rate and outage probability by considering the powerlaw decaying path-loss function for the no-fading and Rayleigh fading communication scenarios. It is observed that the optimum relay selection policy outperforms the other common selection strategies notably, including the ones choosing the relay closest to the source, the relay closest to the destination and the relay closest to the mid-point between source and destination. Index TermsOptimal relay communication, Poisson point process (PPP), stochastic geometry.S. Atapattu and J. Evans are with the

Limited-Feedback Distributed Relay Selection for Random Spatial Wireless Networks

“…Therefore, µ (T ) = lim τ →∞ µ (T, τ ) = 0 for T < d. For other cases of this lemma where T ≥ √ d 2 + τ 2 , the threshold value grows without any bound when τ tends to infinity, which is equivalent to the all-feedback case investigated in [16].…”

“…for each φ ∈ Σ, where Σ is the collection of all countable locally finite subsets of R 2 and s (x) = max {∥x s − x∥ , ∥x − x d ∥} [16]. The optimum relay selection policy, which we denote by P opt , is the one that solves (1) for all φ ∈ Σ.…”

“…The optimum relay selection policy, which we denote by P opt , is the one that solves (1) for all φ ∈ Σ. It is shown in [16] that the outage probability P out (P opt ) and the average rate R ave (P opt ), respectively, satisfy…”

Optimum Reconfigurable Intelligent Surface Selection for Wireless Networks

“…We note that the results in [24] focus on the node distance distribution given the min-max optimum selection criteria, and cannot be directly applied to this paper. The key technical challenges in this paper are to solve the node distance distribution given the min-product and min-sum optimum selection criteria.…”

“…The key technical challenges in this paper are to solve the node distance distribution given the min-product and min-sum optimum selection criteria. These are fundamentally different problems with their own particular technical challenges requiring new solution approaches when compared to those investigated in [24]. Moreover, there are also fundamental differences between RIS-aided networks and relayaided networks in terms of their performance analysis and behaviors, i.e., see [25].…”