A network communications system is provided for allowing a group of computer users in a conference room or similar small work environment to access an Ethernet local area network and to provide peer-to-peer group networking without connection to a backbone network. The filter includes at least one cavity in perpendicular short circuit to the substrate, the positioning and the dimensions of the cavity determining a transmission zero on the filter response curve for attenuating the frequencies situated around this zero. An out of phase condition between the target and reference signals is used to place a timing means in a reset state. The detection optics include a micro-mirror array that redirect the image to a detector. Both bulk semiconductor and silicon-on-insulator embodiments are provided. The polymer composition is particularly suitable for the manufacture of rubber tires with improved rolling resistance.