Publica
Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Robust analog function computation via wireless multipleaccess channels
 IEEE transactions on communications 61 (2013), Nr.9, S.38633877 ISSN: 00906778 

 Englisch 
 Zeitschriftenaufsatz 
 Fraunhofer HHI () 
Abstract
Wireless sensor network applications often involve the computation of predefined functions of the measurements such as for example the arithmetic mean or maximum value. Standard approaches to this problem separate communication from computation: digitized sensor readings are transmitted interferencefree to a fusion center that reconstructs each sensor reading and subsequently computes the sought function value. Such separationbased computation schemes are generally highly inefficient as a complete reconstruction of individual sensor readings at the fusion center is not necessary to compute a function of them. In particular, if the mathematical structure of the channel is suitably matched (in some sense) to the function of interest, then channel collisions induced by concurrent transmissions of different nodes can be beneficially exploited for computation purposes. This paper proposes an analog computation scheme that allows for an efficient estimate of linear and nonlinear functions over the wireless multipleaccess channel. A match between the channel and the function being evaluated is thereby achieved via some preprocessing on the sensor readings and postprocessing on the superimposed signals observed by the fusion center. After analyzing the estimation error for two function examples, simulations are presented to show the potential for huge performance gains over time and codedivision multipleaccess based computation schemes.