Power Allocation Optimization of OFDM-Based In Cognitive Multi-Node Relay Networks sobject to Power Amplifier Nonlinearity

Power Allocation Optimization of OFDM-Based In Cognitive Multi-Node Relay Networks sobject to Power Amplifier Nonlinearity

Power allocation optimization of orthogonal frequency-division multiplexing (OFDM)-based for cognitive multi-node relay networks subject to power amplifier (PA) nonlinearity is studied. Here the nonlinear effects of the PA base station on the received signal to interference and noise ratio (SINR) for each subcarrier in frequency selective fading channel at the secondary receiver is of concern. The adjacent channel interference (ACI) to the PRs should not exceed the interference temperature limit. Interference on the primary user and the maximum transmission power constraint is considered as well. It is also assumed that the base station has a non-linear PA and the relays of linear PA. The power allocation optimization problem is solved through interior point method (IPM). This proposed power allocation scheme is based on IPM, which outperforms equal power allocation (EPA) scheme and is better than without relay scheme. The numerical results are verified through simulation studies.