Beam Forming Antenna Configurations for Use within a Screen-Type CDAA.
Technical rept. no. 44,
ILLINOIS UNIV AT URBANA RADIO RESEARCH LAB
Pagination or Media Count:
Circularly disposed antenna arrays CDAA are used to form highly directional beams for HF transmission, reception and radio direction finding purposes. Concurrent with these applications may be the need to survey preassigned wide angular sectors to the exclusion of other preassigned sectors selective notching. Circularly disposed antenna arrays of the Wullenweber type have large, vertical, circular, backup screens for omnidirectional working without ambiguity. The interior of this screen has cylindrical reflector properties whrerin paraxial rays along any line of arrival come to focus in a region located approximately D4 inside the array, where D is the diameter. Because of this fact it should be possible to obtain controlled sector beam forming using combinations of single vertical monopole antennas to achieve inherent directivity with gain. However, because wave interference is a limiting factor its constructive and destructive effects must be taken into account. A study of these possibilities, capabilities and limitations is considered in this report. Author
- Electrical and Electronic Equipment
- Direction Finding
- Radio Communications