Jarosław Michalak

An efficiency of broadcast mechanisms based on Cluster Heads in clusterized radio network

Efficiency of broadcast transmission based on Cluster Heads in clusterized wireless network has been assessed in this paper. The proposed algorithm uses MPR (Multi Point Relay) method based on Cluster Heads (CH-MPR-BC). Most results were compared with classical solution which uses GateWay nodes at the edge of clusters as retransmitters. It is shown that for clustered network, CH-MPR-BC can be reliable and effective energetically. Tests have been done for static network assuming Free Space Path Loss propagation model with assumed reliability of information delivery in radio link. Energy results were additionally compared with Classical Flooding and MPR algorithms.

WINE: A weighted interconnection node election algorithm for MANET

The concept of Weighted Interconnection Node Election algorithm (WINE) was presented in this article using GateWay nodes and clustered network as an example. The solution uses priorities and level limits for taken weight components connected with mobility, battery level and received signal to noise power ratio for every node. Moreover, account was taken of possible restrictions connected with chosen policy and objective function. As a result of WINE algorithm we can have the clustered network with GW set minimizing energy consumed for retransmission, simultaneously maximizing network living time and probability of information delivery.

COOJA testbed for assessment of broadcast mechanism efficiency in clustered Wireless Sensor Networks

A Wireless Sensor Network (WSN) in definition, is a self-configuring network consisting of small wireless nodes. Sensor nodes are essentially small computers with extremely basic functionality deployed to sense the physical world. The processing unit of each node has limited computational power, a memory and capacity of battery. The WSN are applied in a wide range of scenarios. Some of the application areas are environmental monitoring, agriculture, health and security.

Selection of 5 kW converter leg for power electronic system for residential buildings

Three converter leg variants are analyzed for low power converter used for power electronic system for residential buildings. The two-level Si-IGBT and SiC-MOSFET converters are compared with Si-IGBT three-level T-type converter. Power losses generated in each of these converters over a predicted period of 20 years of operation are contrasted with the cost of converter options. The detailed selection procedure for output inductor is presented in this paper. This procedure shows the influence of the inductor parameters like number of turns, air gap length on its losses, cost and size. Theoretical approach is verified with simulations and experimental results.

Power loss evaluation for medium voltage drive system based on back-to-back three-level NPC converter integrated with induction machine

The paper deals with loss issues in an experimental 3.3 kV drive system consisting of back-to-back three-level NPC converter integrated with an induction machine. This integration significantly reduces the size and weight of the whole drive system. It also allows for a better understanding of loss generation and verifying the effect of operational conditions on such losses e.g. the effect of the converter switching frequency on drive system losses distribution.