Residual Energy Maximization in RIS Aided Cooperative Spectrum Sensing With PUEA: Relative Performance in PS and TS Mode
Avik Banerjee, Santi P. Maity, Veerapu Goutham · IEEE Access · 2025
In this work, a performance comparison on radio frequency (RF) energy harvesting (EH) in power splitting (PS) and time switching (TS) modes in reconfigurable intelligent surfaces (RIS) aided cooperative spectrum sensing (CSS) is made. CSS model considers multiple primary users (PUs), however, one of them seems to be operative or not at a time along with a single PU emulation attacker (PUEA) node. Time frame comprises of sensing-reporting slots in CSS accompanied by EH. A distant dependent model of channel gain in RIS reflector is developed for calculating the harvested residual energy (RE). The primary objective is to maximize the total RE while meeting a predefined detection and false alarm probabilities of PU along with the individual secondary user’s (SU’s) energy causality constraint. The optimal values of sensing duration, power splitting factor (in PS) and amplifying gain are calculated through Lagrange method. Simulation results show the efficacy of the proposed work due to RIS on total RE highlighting a gain of 45% and 38.97% for PS and TS mode compared to the existing work while maintaining the above mentioned constraints. Performances of RE with the change in the placement of RIS near/far to PU (in presence or absence of PUEA) and the same near/far to PUEA are analyzed for both PS and TS mode. If PU transmit power is increased, the maximum value of RE for PS mode (both in presence and absence of PUEA) is achieved when RIS is placed near to the SU transmitter. The maximum value of RE for both PS and TS modes are found to be at the middle when RIS is moved from the latter position to nearer to the PUEA.