This paper presents a novel method to construct a heterogeneous wireless sensor network with small world effect, which is built on super links to a sink as short cut consisting of super nodes with more energy, memory and processing capability.

Energy efficiency strategies in link level between sensor nodes are important because most energy consume in transmit and receive.

Research and Realization of LLC Advanced Link in TETRA Digital Trunk Base Station;

Design of optical fiber link ethernet for a port material transportation system;

We take the transmitting and receiving power of the optical communications equipment as the main discussion object and combine with practical project construction,the solution to the attenuation and amplification in optical fiber links with different distances are described.

This article analyses in theory the factors that affect the specifications of noise and nonlinearity in optical fiber link, gives the expressions of CNR、CSO and CTB as well as the results measured in practical optical fiber link from the headend of WHCATV to Jinghan Garden.