ARCH: Adaptive Resource Allocation for Cooperative Transmission in Hybrid SWIPT-Enabled Wireless Powered Sensor Networks

This paper adopts the Simultaneous Wireless Information and Power Transfer (SWIPT) concept in designing an adaptive optimal resource allocation algorithm for cooperative transmission in hybrid SWIPT-enabled wireless power sensor networks. The SWIPT concept enables the sensor nodes to utilize the radio-frequency signals to transmit energy along with their sensed data to the cluster heads. We consider having a hybrid access point (HAP) that acts as both power transmitter and a communication gateway. Hence, a cluster head that is two-hops away from the HAP sends its aggregated data along with its harvested energy to its neighboring cluster head that is one-hop away from the HAP. The presented ARCH algorithm is an energy efficient iterative scheme proposed for energy efficiency optimization for cooperative transmission in a hybrid SWIPT-enabled wireless powered sensor network. For the intra-cluster and inter-cluster communication, sensor nodes adaptively choose time switching or power splitting mode based on their energy dispersed value. Also, we present a frame structure for enabling the hybrid SWIPT operation and we formulate the optimization problem by jointly optimizing the transmit powers, the SWIPT ratios, achievable rates, and time for transmission. Simulation results show that the proposed ARCH algorithm is superior to benchmark schemes in terms of energy efficiency, achievable rate, and dispersed energy.