Experimental demonstration of a 35 GHz holographic antenna
We have developed a novel two-dimensional grating antenna based on microwave holography. The two-dimensional grating (hologram) is formed on a dielectric substrate and fed by an integrated surface wave exciter. Various design issues will be presented, as will a 35 GHz demonstration prototype antenna designed, fabricated, and tested. Measured radiation patterns closely agreed with the theoretical prediction.
Volume-type holographic antenna
A new type of holographic antenna based on the principle of the volume hologram is proposed. The characteristics of the prototype are examined. The antenna has a unidirectional beam with a front-to-back ratio of 20 dB. The practical frequency handwidth is about 10 percent of the center frequency. The antenna is unique in that the feed point is placed in the plane of the holographic plate so that both feeder and the holographic plate could be made out of one printed circuit board for easy flush mount installation or mass production, although the feeder of the prototype antenna was a pyramidal horn.
Visualization of internal structure by microwave holography
Microwave holography was used for the visualization of an internal structure within a dielectric. Descriptions are given of 1) the preparation of the liquid crystal film to be used for mapping the microwave field, and 2) the application of the liquid crystal film in the fabrication of a microwave hologram to visualize the internal structure within a dielectric.