Types of Satellite Antennas
Satellite antennas are made as solid / all-stamped, mesh and precast / sectional. The solid ones are made of a whole metal sheet and have a shape without technical holes and joints. Their signal reception quality is better than the others, and the design is less prone to kinks and defects during operation.
Mesh antennas are assembled from strips, forming a receiving grid. Their advantage is less windage, so mesh satellite dishes are preferred in areas with increased wind load.
Prefabricated antennas are made of petals and can be compactly packed for transportation and long-term storage. They, like sectional ones, are convenient for regular transfer, as they are easy to fold and allow you to quickly deploy the system. Cons of the design – in the weak joints of the petals, which are easily broken and require regular professional maintenance.
Mesh satellite dishes have slightly worse signal quality than all-metal antennas, but not due to technical holes. Since for the correct reflection of the beam the shape of the mirror must be strictly parabolic, it is planned to create a mesh antenna with a minimum deviation from the correct shape. But the grid lines are still located at the shortest distance from each other – in a straight line, thus, in fact, the paraboloid of the grid antenna is discrete, and not of a regular continuous shape.
If in the frequency range Ku only a deviation from the correct form by 6 mm is allowed, then in the C range, this level is already 19 mm due to the wavelength. This deviation is much easier to observe. Because of this, mesh satellite systems are much more often used in the C-band, their useful level of the received signal is sufficient for full broadcasting.
Materials for the manufacture of satellite dishes have different reflectivity. Plastic coated with a radio-reflective layer loses its shape under the influence of direct sunlight.
The steel satellite digital antenna is heavy and often rusts. Aluminum, it would seem, fits most of the requirements, but it bends and crackes very easily. Composite materials are expensive in production.
When installing a satellite dish, it is important to take into account and observe the suspension factor, which directly affects the periodic adjustment of the antenna, and also determines the protection against external factors: vibration, mechanical damage, wind load, etc. Brackets for satellite dishes are common in two forms: azimuthal and polar. In the first case, the satellite system is rigidly fixed at the necessary angles to the horizon and azimuth. In the second case, the suspension takes into account the possibility of rotation of the suspension in azimuth, taking into account the location of the satellites.
A key factor in assembling a satellite dish kit is the focal length. If the equipment is selected for you by a qualified specialist, you can do without studying the physics of the process.
In general, satellite systems are divided into short-focus and long-focus. It is up to you to decide which satellite dish to choose, however, in each case, depending on the tasks, it is worth checking the necessary focus and the ratio of the diameter of the antenna to the focus. This parameter directly depends on the radiation pattern; in addition, it is affected by both the satellite and the required signal level.
In short, for easy viewing of TV channels or for not very active use of Internet access, select long-focus antennas with pre-installed irradiation mount brackets. Otherwise, it is better to contact a specialist to calculate all the data. Otherwise, there is a high probability of a mistake, and instead of an expensive satellite system, get an idle set of puzzles.
If you decide to make a satellite dish with your own hands, note that the main difficulty is not in the production of a mirror, but in the converter. It is difficult to make the converter yourself because of the technological filling. But as a mirror, almost any paraboloid of the desired geometry, directed in the right direction and fixed in the right place to the irradiator with a converter, is suitable. Such a design is quite capable of providing stable communication in one direction, for example, receiving a television signal. Two-way satellite communications will require precise settings both in range and in the received signal, one can not do without a specialist here.
But with the current saturation of the market with inexpensive satellite dishes, it is advisable to purchase a finished product of a satellite dish system and get full functionality.