The Hughes antenna design offers an opportunity to deduce total antenna diameter, based on shroud constraints on the maximum length of the vertical support struts. Unfortunately, the range of possible parameters is too great to do more than generally constrain plausible upper and lower limits on antenna diameter.

Two cases are considered, the 76-foot and 86-foot length Titan-4 Centaur payload shrouds. The maximum strut length in each case may be taken to be somewhere between the length that extends from the top of the Centaur upper stage to the base of the cone of the shroud [the **short** length] and the length that extends in a direct line from around the outer diameter of the Centaur into the shroud cone [the **long** length].

These dimensions are:

Shroud short long 76' 35.4' 44.2' 86' 43.7' 52.5'These dimensions bound the

The **depth (d)** and **Diameter (D)** of the parabolic reflector antenna are related to the **focal length (f)** is a function of

(Diameter)exp2 f = ----------- 16*(depth)Parabolic reflectors with a

Sources

- ANTENNAS, 2nd edition, John D. Kraus, McGraw-Hill, ISBN 0-07-0354 22-7
- THE ARRL ANTENNA HANDBOOK, The American Radio Relay League, many editions

Implemented by Charles P. Vick, Sara D. Berman, and

Christina Lindborg, 1997 Scoville Fellow

Maintained by Robert Sherman

Originally created by John Pike

Updated Sunday, March 09, 1997