Elliptical satellite dish

In satellite communications, elliptically shaped dishes are often used in order to achieve a narrow main beam pattern and low side lobe levels in a particular directions. The alternative is to use larger circular dishes, but smaller dishes are preferred as they less obstrusive.

It is desired to minimise the side lobes in the direction towards other satellites, adjacent either side along the geostationary orbit. This minimises interference to and from those satellites. In the case of exceptionally small satellite dishes, as used for satellite TV, the width of the main beam itself and the locations of the adjacent satellite are of importance and it may be possible to make the width of the elliptical dish such that the locations of the probable adjacent satellites fall in the null between the main beam and the first sidelobes.

When installing an elliptical dish it may be possible to alter the orientation of the ellipse by tilting the entire dish clockwise or anticlockwise while facing the satellite.

In the case where the wanted satellite is on approximately the same longitude as the satellite, the satellite is at the top of the geo orbit arc as seen across the sky. The top of the geo orbit is horizontal and it is appropriate in this case that the wide dimension of the elliptical dish be sideways. The broad width of the dish is thus aligned parallel with the orbit.

This image illustrates the case of a satellite some way away from the highest point on the geo arc. The dish needs tilting so that its minimum sidelobes line up with the adjacent satellite.

The dish is tilted clockwise, viewed in the direction towards the satellite and its larger diameter is roughly parallel with the line of the nearby satellites.

The diameter of the main beam is smaller with large diameter dishes. In the case of an elliptical dish the main beam shape is normally also elliptical with the narrow dimension sideways, if the broad dimension of the dish is also sideways.

Speakers (DIRECTV)
  • One(1) DIRECTV DUAL LNB 18
  • Genuine DirecTV Product
  • Excellent isolation with Superior Low Noise
  • Compatible with DirecTV system
  • For use with one or two receivers
Direct TV 46DTVDE218 Round Dish W/dual Lnb
CE (Direct TV)
  • 18 inches directv dish
  • dual lnbf for satellite 101w directv. connect two receivers
  • it doesnot work with Directv genie receivers or h25 receivers
  • long foot mast for wall or roof mount.
  • standard definition only
Sharp Electronics DishPro Plus LNB
CE (Sharp Electronics)
  • DishPro Plus LNB. Dual outputs to two single-tuner receivers or two-dual tuner receivers.
  • Third orbital location can be fed into this LNBF
DMS International DSS922 DSS Dual LNBF for Anik F3 118.7 & 119 Satellite Dish
CE (DMS International)
  • Designed to receive 119 & 118.7 at the same time
  • Dual output allows you to use 2 receivers at the same time and recieve all the channels from both 119 and 118.7 at the same time.
  • Works on Echostar 3 at 61.5, Echostar 6/8 at 110, Echostar 7 at 119, Anik-F3 at 118.7W, Echostar 1/2 at 148,
  • And other DSS satellites including DirecTV and Bell ExpressVu
  • Works with Dish Network Dish 500 to Receive 110/118/119 Satellites when used with another Legacy LNB
  • Works with Dish Network Receivers and FTA
DirecTV DirecTV 18" Round Satellite Dish with Dual LNB (18SINGLEDISH)
Speakers (DirecTV)
  • Rectangular style Feed Tube
  • Reflector Material: 0.033 Galvanized Steel
  • 2 dia. Universal Wall/Roof mount

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