Relay antennas - transmitters
How can there be more transmitters than antennas?
Antennas used by telecom operators can transmit signals used by different technologies (2G, 3G, 4G and 5G) in several frequency bands. The same antenna can therefore, for example, "carry" a GSM transmitter in the 900 MHz band, a 3G UMTS transmitter in the 2100 MHz band and a 4G LTE transmitter in the 1800 MHz band.imprimer
Are there antennas that don’t appear on Cartoradio?
Only antennas with an equivalent isotropic radiated power (EIRP) greater than 5 watts are shown in Cartoradio, with some exceptions:
- the antennas used by the Civil Aviation and the Ministries of Defence and the Interior are not displayed for security reasons;
- antennas, and more generally equipment used only for reception, such as rake antennas and satellite dishes, are not displayed.
Furthermore, antennas with an EIRP of more than 5 watts may have been installed before an authorisation file was received by ANFR. They do not appear in Cartoradio and must not be operational.
Why is a measurement not on Cartoradio?
First make sure you have selected "All" in the "Measurements" menu. This means that you want to see all measurements since 2001 - not just those less than two years old. Once that is done, check that the measurement was made by an accredited laboratory. ANFR only displays measurements sent by accredited laboratories. Finally, there may be a display error: please report it to us.imprimer
What is the framework in which relay antenna measurements are made?
Measurements are not systematic when transmitters are installed. They are made at the request of local residents. Moreover, a measurement is never the measurement of a specific transmitter but the "sum" of the contributions of the various radio devices in the neighbourhood at a given location.
What are the purple squares? I can't find them in the key.
The ANFR uses the national geographic institute map background which is very rich in information - the purple square you mention is such information and therefore is neither a transmitter nor a measurement.
Why is a site on the map when it isn’t visible?
The figurative symbols on Cartoradio correspond to the authorisations issued by ANFR after consultation with the Commission des Sites et Servitudes (COMSIS). Once this agreement has been obtained, the operator has one year to proceed with its installation project. A certain amount of time may therefore pass between the authorisation and the actual implementation of the site.
There are numbers on the squares. What do they mean?
A square (blue or red) usually represents a set of objects, either several radio sites, or a series of electromagnetic field measurements. The number therefore corresponds to the number of sites or the number of measurements at the indicated location. The higher the number, the more you need to zoom in to view the different objects separately.
Why do the numbers in the grouping squares of nearby sites vary depending on the map scale?
The square symbol represents a group of sites close to each other. The definition of proximity varies depending on the map scale. The purpose is to eliminate illegible clusters of symbols by replacing them by a single square symbol with an indication of the number of sites in close proximity to each other that it represents. You must zoom in to view the different sites separately. To zoom in quickly, keep the SHIFT pressed, click on the map and draw the rectangle to zoom in on using the mouse.
When I enlarge the map, why do the squares indicating the sites disappear?
This is normal, no information has been lost. When you successively enlarge the map, the level of detail is better and it becomes possible to gradually isolate each site at its exact location; the square symbols gradually disappear to be replaced by the symbols associated with television, mobile phones, etc.
Why doesn't the address I typed in the search field appear?
If your address is a private road, then it is not listed in the national geographic institute database.
Why are only field measurements displayed and not sites?
When sites are densely populated, it may be necessary to zoom in to see the measurements and sites together. In that case, a "Please zoom in" alert window with a blue square symbol appears at the centre of the lower edge of the screen.
Why does an error message appear when I enter the postal code of my town?
You must write the name of your municipality in full, otherwise the error message is displayed.