Demonstration of a new degree of freedom in wireless routing
Yong Jun Chang, Haejoon Jung, Mary Ann Ingram · 2010
Cluster transmission, also called Concurrent Cooperative Transmission (CCT) in this paper, enables a collection of power-constrained embedded sensors to transmit as a group and achieve a transmit range that is much greater than the range of a single device. CCT brings a new flexibility to the network layer; for example, CT can be used for load balancing or for overcoming a partition. CCT is also the basis for a fast, contention-free method of broadcasting. A method for achieving cluster transmit time synchronization is described for the non-coherent FSK type of modulation. In this method, nodes derive their synchronization from a received packet. Experimental results are presented for an indoor office environment at 2.4 GHz. Root mean squared (rms) transmit time spreads are reported for a two-hop network as well as for a "ping pong" experiment, which has ten consecutive CCT hops. Examples of CCT range extension are also presented.