Is it correct that some automated gates can be activated by mobile phone?
GSM Gate Openers allow you to open gates, doors, shutters and barriers through your mobile phone. You can simply dial a number to open your gates.
The unit itself is is fitted with a SIM Card. When access is required, a call is made to the phone number of the SIM Card within the GSM Gate Opener.
The unit allows to call to ring once, to acknowledge the call and to allow the unit to read the number calling it - Caller ID
If the unit is set to allow any caller, or to use Caller ID access, it looks for a match of phone numbers in its database and if found activates the on-board relay. If there is no match the call is simply ignored.