8 research outputs found
Joint Data Routing and Power Scheduling for Wireless Powered Communication Networks
In a wireless powered communication network (WPCN), an energy access point
supplies the energy needs of the network nodes through radio frequency wave
transmission, and the nodes store the received energy in their batteries for
their future data transmission. In this paper, we propose an online stochastic
policy that jointly controls energy transmission from the EAP to the nodes and
data transfer among the nodes. For this purpose, we first introduce a novel
perturbed Lyapunov function to address the limitations on the energy
consumption of the nodes imposed by their batteries. Then, using Lyapunov
optimization method, we propose a policy which is adaptive to any arbitrary
channel statistics in the network. Finally, we provide theoretical analysis for
the performance of the proposed policy and show that it stabilizes the network,
and the average power consumption of the network under this policy is within a
bounded gap of the minimum power level required for stabilizing the network
An Energy-Efficient Controller for Wirelessly-Powered Communication Networks
In a wirelessly-powered communication network (WPCN), an energy access point
(E-AP) supplies the energy needs of the network nodes through radio frequency
wave transmission, and the nodes store their received energy in their batteries
for possible data transmission. In this paper, we propose an online control
policy for energy transfer from the E-AP to the wireless nodes and for data
transfer among the nodes. With our proposed control policy, all data queues of
the nodes are stable, while the average energy consumption of the network is
shown to be within a bounded gap of the minimum energy required for stabilizing
the network. Our proposed policy is designed using a quadratic Lyapunov
function to capture the limitations on the energy consumption of the nodes
imposed by their battery levels. We show that under the proposed control
policy, the backlog level in the data queues and the stored energy level in the
batteries fluctuate in small intervals around some constant levels.
Consequently, by imposing negligible average data drop rate, the data buffer
size and the battery capacity of the nodes can be significantly reduced
Adaptive Molecule Transmission Rate for Diffusion Based Molecular Communication
In this paper, a simple memory limited transmitter for molecular
communication is proposed, in which information is encoded in the diffusion
rate of the molecules. Taking advantage of memory, the proposed transmitter
reduces the ISI problem by properly adjusting its diffusion rate. The error
probability of the proposed scheme is derived and the result is compared with
the lower bound on error probability of the optimum transmitter. It is shown
that the performance of introduced transmitter is near optimal (under certain
simplifications). Simplicity is the key feature of the presented communication
system: the transmitter follows a simple rule, the receiver is a simple
threshold decoder and only one type of molecule is used to convey the
information
On Energy Allocation and Data Scheduling in Backscatter Networks with Multi-antenna Readers
In this paper, we study the throughput utility functions in buffer-equipped
monostatic backscatter communication networks with multi-antenna Readers. In
the considered model, the backscatter nodes (BNs) store the data in their
buffers before transmission to the Reader. We investigate three utility
functions, namely, the sum, the proportional and the common throughput. We
design online admission policies, corresponding to each utility function, to
determine how much data can be admitted in the buffers. Moreover, we propose an
online data link control policy for jointly controlling the transmit and
receive beamforming vectors as well as the reflection coefficients of the BNs.
The proposed policies for data admission and data link control jointly optimize
the throughput utility, while stabilizing the buffers. We adopt the
min-drift-plus-penalty (MDPP) method in designing the control policies.
Following the MDPP method, we cast the optimal data link control and the data
admission policies as solutions of two independent optimization problems which
should be solved in each time slot. The optimization problem corresponding to
the data link control is non-convex and does not have a trivial solution. Using
Lagrangian dual and quadratic transforms, we find a closed-form iterative
solution. Finally, we use the results on the achievable rates of finite
blocklength codes to study the system performance in the cases with short
packets. As demonstrated, the proposed policies achieve optimal utility and
stabilize the data buffers in the BNs
Joint Data Routing and Power Scheduling for Wireless Powered Communication Networks
In a wireless powered communication network, an energy access point (EAP) supplies the energy needs of the network nodes through radio frequency wave transmission, and the nodes store the received energy in their batteries for their future data transmission. In this paper, we propose an online stochastic policy that jointly controls energy transmission from the EAP to the nodes and data transfer among the nodes. Our proposed policy is designed using a quadratic Lyapunov function to capture the limitations on the energy consumption of the nodes imposed by their battery level. The proposed policy is adaptive to different channel statistics of the network. We provide theoretical analysis for the performance of the proposed policy and show that it stabilizes the network. Moreover, the average energy consumption of the network under this policy is within a bounded gap of the minimum energy level required for stabilizing the network
An Energy-Efficient Controller for Wirelessly-Powered Communication Networks
In a wirelessly-powered communication network (WPCN), an energy access point (E-AP) supplies the energy needs of the network nodes through radio frequency wave transmission, and the nodes store their received energy in their batteries for possible data transmission. In this paper, we propose an online control policy for energy transfer from the E-AP to the wireless nodes and for data transfer among the nodes. With our proposed control policy, all data queues of the nodes are stable, while the average energy consumption of the network is shown to be within a bounded gap of the minimum energy required for stabilizing the network. Our proposed policy is designed using a quadratic Lyapunov function to capture the limitations on the energy consumption of the nodes imposed by their battery levels. We show that under the proposed control policy, the backlog level in the data queues and the stored energy level in the batteries fluctuate in small intervals around some constant levels. Consequently, by imposing a negligible average data drop rate, the data buffer size and the battery capacity of the nodes can be significantly reduced