Cassegrain - 1

Gs = 41.9dB, SLL= -19dB, Gdel = 35.9dB, SLL = -15dB

Dm = 160, Ds = 20, FmFs =100, Feed angle = 20 deg

1. Structure

Five Deielectric Rod Feed

16.03.2018

1. Structure view

Dielectric: er=2.73, tand=0.001 (Rexolite)

z=0 port plane

Rod diameter

Square waveguide width

Full length of structure 43.43mm

Central dielectric rod length 24.50mm

Side dielectric rods length 18.60mm

Phase center z= 35.66 mm (7.77mm away from sum element tip toward square wg)

phase center-to-rod ground plane = 16.73

Waveguide’s size 2.1x2.1mm

Start diameter of the rod 2.1mm; end diameter of the rod 0.79mm

Full diameter 10.16mm

2. Results

2.1 Farfield of the original size of the rods

2.2 Farfield of the feed with 50% rod’s length increased

Feed for Cassegrain-1

2.3 Farfield with increased spacing between rods from 0.6mm to 1mm

Feed for Cassegrain-2

2.4 Farfield for not lofted dielectric rod in the waveguide

2.5 Reflection coefficient

2. Results Farfield results with sum farfield pattern of the feed system

Cross polar

Scan 9.6deg

Cross-polar scan 9.6deg

∆-Elevation pattern

Cross-polar of ∆-Elevation pattern

∆-Elevation pattern 9.6deg

Cross-polar of ∆-Elevation pattern 9.6deg scan

Cassegrain-2

Dm = 160, Ds = 24, FmFs =120, Feed angle = 22.5 deg