Spectrum Sharing-based Multi-hop Decode-and-Forward Relay Networks under Interference Constraints: Performance Analysis and Relay Position Optimization

TL;DR

This paper derives analytical expressions for outage probability, bit error rate, and ergodic capacity of spectrum sharing multi-hop relay networks, and proposes an optimal relay placement scheme to enhance performance under interference constraints.

Contribution

It provides the first closed-form expressions for key performance metrics and introduces a relay position optimization method for cognitive multi-hop relay networks.

Findings

Optimal relay placement improves SNR by over 1 dB.

Analytical formulas are validated by Monte-Carlo simulations.

Multi-hop DF relaying offers advantages in cognitive radio environments.

Abstract

The exact closed-form expressions for outage probability and bit error rate of spectrum sharing-based multi-hop decodeand- forward (DF) relay networks in non-identical Rayleigh fading channels are derived. We also provide the approximate closed-form expression for the system ergodic capacity. Utilizing these tractable analytical formulas, we can study the impact of key network parameters on the performance of cognitivemulti-hop relay networks under interference constraints. Using a linear network model, we derive an optimum relay position scheme by numerically solving an optimization problem of balancing average signal-to-noise ratio (SNR) of each hop. The numerical results show that the optimal scheme leads to SNR performance gains of more than 1 dB. All the analytical expressions are verified by Monte-Carlo simulations confirming the advantage ofmultihop DF relaying networks in cognitive environments.