Formula for dB down off axis

(Read 4683 times)

chumleymobile Member ★★ Offline Posts: 2	Sep 13^th, 2009 at 9:20pm Sirs/Ma'ams, I've got the formula for dB down off axis for 3 db beamwidth ie (theta/3db beamwidth)^ x 12, anyone have the formula for dB down ref to 10 dB beamwidth? Many thanks. Chumleymobile
Back to top	IP Logged

Admin1

YaBB Admin
★★★★★
Offline

Posts: 1215

Reply #1 - Sep 14^th, 2009 at 11:17pm

You may try this beamwidth calculator but please be aware that the result is approximate.

The shape of the main beam is affected by the power illumination distribution across the dish. The feed has higher gain towards the centre of the dish and lower gain towards the edge of the dish. The effect is to greatly reduce the off-axis sidelobe levels with some limited on-axis gain reduction.

Best regards, Eric.

WWW

IP Logged

chumleymobile Member ★★ Offline Posts: 2	Reply #2 - Sep 15^th, 2009 at 3:24pm Eric, Good stuff, thanks. Br's, C'mobile
Back to top	IP Logged

Pages: 1

Send Topic | Print

Disclaimer, Terms of Use and Privacy Forum User Agreement Forum rules Cookie policy.