• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

Satellite Secret's (EIRP in dB) Dish Size Formula

Messages
13
Likes
0
My Satellite Setup
Satellite
My Location
ksa
#1
:eek: When you are looking at satellite footprints, you will often find ones which give a power reading in dB rather than a dish size required.
Does anyone know the exact formula for the relationship between EIRP (dbW), dish size (m) and LNB noise figure (d:cool:, assuming clear weather conditions.
 

Analoguesat

Administrator
Staff member
Messages
44,793
Likes
7,557
Location
Scottish Borders
My Satellite Setup
TM 5402HD
Skybox F3
Sky+ UK.
My Location
Scottish Borders
#2
This page should give you a reasonable idea.

http://www.flysat.com/dish.php
 

Orthoclipse

Regular Member
Messages
127
Likes
0
My Satellite Setup
Various
#3
Following on from that, does anyone have a list of 'EIRP vs Dish Gain' figures?

The reason I ask is that different dishes of the same size can have different gain numbers and it's never clear from the 'EIRP vs Dish size' tables what the gain of the dish is supposed to be.
 

Orthoclipse

Regular Member
Messages
127
Likes
0
My Satellite Setup
Various
#5
Dish gain @ 11GHz with 60% efficiency

47 dBW 75 cm (36.5 d:cool:
46 dBW 80 cm (37.1 d:cool:
45 dBW 90 cm (38.1 d:cool:
44 dBW 90 cm (38.1 d:cool:
43 dBW 100 cm (39.0 d:cool:
42 dBW 110 cm (39.8 d:cool:
41 dBW 120 cm (40.6 d:cool:
40 dBW 120 cm (40.6 d:cool:
39 dBW 135 cm (41.6 d:cool:
38 dBW 150 cm (42.5 d:cool:
37 dBW 180 cm (44.1 d:cool:
36 dBW 240 cm (46.6 d:cool:
35 dBW 300 cm (48.6 d:cool:
34 dBW 355 cm (50.0 d:cool:
33 dBW 400 cm (51.0 d:cool:
32 dBW 450 cm (52.1 d:cool:
 

izefisherman

Regular Member
Messages
72
Likes
0
My Satellite Setup
Ku: 2.4m Aerial PFA / Invacom SNF-031,
C: 1.2m Aerial PFA / MTI 15k,

DM7020-S, DM500S, C-Tech 2100, VBOXII
My Location
Finland
#6
The FEC of the transmitted signal is also a major factor here. The difference for error free reception between 2/3 and 7/8 FEC is in the order of 2dB. That is quite much when translated into dish size.
 

member91040

Regular Member
Messages
1,482
Likes
0
My Satellite Setup
DISH TV,DIRECT DD+,
TATA SKY,HATHWAY,
NOKIA 9660S,
PCI SAT CARD TWINHAN NSS6, PAS7/10, ASIASAT3S, INSAT,INETEL SAT, EUROSTAR, DremBox, & Multi LNB'S
My Location
INDIA
#7
Here you will find , how to cal...!

h**p://w**.tutorialsweb.com/satcom/link-power-budget/link-power-budget-index.htm