A multisource antenna includes at least two excitation sources and for spatially channeling energy picked upradiated by the excitation sources and providing for frequency decoupling between the bands respectively corresponding to the waves receivedtransmitted by the sources. The mechanisms determine a number of data elements to be included in each set of data elements to be sent to each processing element of a data processing system, and perform a comparison operation on at least one set of data elements. Modifications are possible within the scope of this invention. The lower end of the first arm and the upper end of the second arm are hingedly attached. Therefore, the complexity of the vector quantization could be decreased effectively.