Dilemma at RF Energy Harvesting Relay: Downlink Energy Relaying or Uplink Information Transfer?

Abstract

Performance of RF powered communication network is bottlenecked by short downlink energy transfer range and doubly-near-far problem faced in uplink information transfer to Hybrid Access Point (HAP). These problems can be resolved by cooperation of an RF energy harvesting node R present between HAP and RF energy harvesting information source S. However, there lies a dilemma at R on whether to transfer its harvested energy to S or to act as an information relay for transferring its data to HAP in a two-hop fashion. This paper resolves this dilemma at R by providing insights on its optimal positions suited for either energy relaying (ER) or information relaying (IR). It also investigates the possibilities of integrated ER and IR along with the regions where neither ER nor IR will be useful. In this regard, while considering Rician fading channels and practical nonlinear RF energy harvesting model, the expression for mean harvested dc power at S via energy transfer from HAP and ER from R is first derived. The closedform outage probability expression is also derived for decodeand-forward relaying with maximal-ratio-combining at HAP over Rician channels. Using these expressions insights on optimal relaying mode is obtained along with global-optimal utilization of harvested energy at R for ER and IR to maximize the delaylimited RF-powered throughput. Numerical results validate the analysis and provide insights on the optimal relaying mode. Index Terms-Integrated information and energy relaying, practical RF energy harvesting model, Rician fading, outage analysis, throughput maximization, generalized convexity

Optimal Green Hybrid Attacks in Secure IoT

“…The default simulation parameters are: P S = 10 dBm, P J m = 13 dBm, P m = 13 dBm, g SU = −60 dB, g SA = g AU = −70 dB, σ 2 = −100 dBm, ν = 0.7, P ft = P fr = −0.33 dBm, ρ d = −10.33 dBm/bps/Hz as the decoding power consumption per unit rate at A considering Mica2 mote and CC-1000 transceiver to represent low power IoT system [9], [10] and references therein.…”

“…It may be noted here the decoding rate r A chosen at A has to satisfy the constraint r A ≤ R A , because R A is the maximum rate over S-A link as available for eavesdropping. Similarly, as a jammer, A transmits a jamming signal at power P J , adopting conventional power consumption model for transmitter [9], [12]. Therefore, the power consumption in jamming mode is modelled as: P ft + (P J /ν).…”

Optimal Channel Estimation for Hybrid Energy Beamforming Under Phase Shifter Impairments

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