Filtering inclined incident microwave by composite structure of single-negative materials

Transmission as functions of the incident angles of microwave through an SRRs (split ring resonators) array, a metal wire array, and their assembly are calculated. It is shown that the transmission varies greatly with the incident angles. The assembly filters incline-incident microwave effectively, and the transmission through the assembly is high only when the incident direction is along the normal of the assembly surface. The assembly may be used as filter of incident direction, and has potential application in transmission imaging of microwave.