Citation
Abstract
A new type of dichroic plate is described that can be completely transparent at lower frequencies and can reflect the higher frequencies without the use of a dielectric substrate. The basic concept of the new design is to use slots in a moderately thick metallic plate for the transmit band and to use chokes in the slot to reflect the upper frequency bands. Thus, the dichroic plate is transparent at the lower frequency band and reflective at the upper frequency bands without using a dielectric. An experimental plate designed to be transparent at 8.4 to 8.45 GHz (X-band) and reflective at 31 to 35 GHz (Ka-band) using a single-depth choke was fabricated and tested. For X-band, the calculated and measured resonance frequency for the transverse magnetic (TM) mode and the transverse electric (TE) mode differed by less than 0.3 percent. The transmission coefficient at Ka-band (measure of reflectivity) was better than -30 dB for TE and -40 dB for TM.
Details
- Volume
- 42-129
- Published
- May 15, 1997
- Pages
- 1–11
- File Size
- 242.9 KB