Garage door opener
The first garage door Opening had the remote which acted as the transmitter and an opener which acted as the receiver.The function of the remote was to transmit within a limited frequency and the function of the opener was to notice a change in the amplitude and after that the door was opened or closed, depending on the position of the door. Therefore the mechanism of the garage door opener in the beginning was quite simple. Even if the power and range of the garage door opener was low but still it was powerful enough to interfere with the other receivers in the vicinity.
Then the wireless garage door openers evolved. It came in to the market because a large number of garage door opener had started operating at the same frequency. In order to overcome this problem, a more advanced form of garage door opener was developed in form of wireless. This was developed so that the receiver doesn't interfere with other garage door opener.
Present Day Garage Door Opener
In the present market of garage door openers, they offer a wide variety. Most of the garage door openers these days depend on the technology of rolling code.The encoders in the transmitter and decoder in the receiver work on this technology in order to avoid recording of a code and replaying it while opening the car door. A new code is generated using an encoder, when the transmitter sends a code. After receiving the right code, the receiver makes a new code that will be accepted in the future, with the help of the encoder.
There have been a lot of expectations of the garage door opener which were not really required. The expectations were like a light that turns on when the door is opened and is automatically switched off when the door closes and motion sensors if any one enters the garage premises, a feature called remote lock out which turns off the radio receiver when you are on vacation.
Due to safety measures some of the features must be declined or refused:
- The carbon monoxide sensor to open the door lowers security and might lead to loss of life, if it doesn't perform perfectly.
- Door activation over the internet by the owners to open their garage doors for delivery from their office would infringe the rule of safety that suggests that the door must be in the line of sight of the person who controls the door for safety measures.