The battery lifetime of wireless devices is crucial for maintaining the communication. Wireless powered communication (WPC) is an important paradigm to meet energy needs for wireless devices. In this study, a WPC system which consists of a user equipment (UE), a power transfer station (PTS) and a receiver node (RN) is considered and it operates according to harvest-then-transmit protocol. In this system, we assume that the UE does not have its own power source. All terminals operate in half duplex mode and have single antenna. In the first transmission period, the UE harvests energy from the PTS over Fisher-Snedecor F fading channels. Then, the UE sends message signal to the RN by using the harvested energy over κ-µ/shadowed fading channels in the second transmission period. Since the wireless transmission channels between communicating terminals can be subject to different fading characteristics due to the nature of wireless mediums, we assume two different composite fading conditions for the first and second transmssion periods. For the considered system, we obtain an approximate outage probability (OP) expression since the exact OP integral has an intractable form. Finally, we illustrate numerical results by evaluating the derived approximate OP expression for different values of fading parameters, time splitting factor (α) and energy conversion efficiency (η). Besides, the exact results are also calculated based on numerical evaluation of the exact OP integral and the exact results are also included in the numerical results. It is observed that the approximate results are close to the exact results.
Anahtar Kelimeler: Outage Probability, Wireless Power Transfer, Composite Fading