How to connect a gate intercom or external CCTV without excavation of the yard or driveway.
As a society we are becoming more security conscious as we look to provide safety to our families and property. It is common for new homes to be built with intercom and cctv in mind with at least the cables being laid allowing for installation at a later date.
What about older homes? How do we upgrade our security without digging up the lawn?
Retrofitting surveillance or intercom into older properties may require installation of suitable cables. Where old systems are being replaced it is possible to reuse the old cables by connecting a 2-wire intercom system or upgrading old analogue cameras to HDCVI (for up to 4K rersolution) using the old coaxial cable. But what about where there are no cables and you want to add intercom and cctv to your new front fence and electric gate? How can you achieve connectivity without digging up the lawn or worse, the concrete or paving? The answer is to use wireless but not how you might think.
A word about WiFi built-in to intercoms
WiFi is ubiquitous which is to say it is everywhere. This sounds like it should be an advantage but with Video intercom it actually works the other way. Video requires a good clean strong signal for realtime transfer (seeing a delayed or broken video stream is not very useful when trying to communicate). Intercom devices with WiFi tend to use the 2.4GHz band as it has best performance through walls which is needed for intercom systems. 2.4GHz also is the most commonly used band and the ability to penetrate walls means that all your neighbours are broadcasting WiFi into your home as well as your own WiFi. The signals are encrypted (they should be!) so this just becomes noise that the WiFi system then has to listen through to pickup your intercom signal. If you add in repeaters / extenders, microwave ovens, reflections from walls, and the sheer number of portable devices all connecting to WiFi, it becomes a very noisy environment for intercom. Expecting a WiFi intercom mounted on the other side of the fence / wall with a small antenna and low power to provide a clear strong signal to the router is wishful at best. Even with range extenders, the latency and noise works against the system and it becomes unreliable. Cable is always the most reliable way to connect and outdoors a wireless bridge can give similar connectivity at a fraction of the price of laying cables.
A better way with a Wireless bridge
Before considering a wireless bridge it is important to ensure there is clear line of sight between the 2 ends of the link. The options to use poles and roof mounts will raise the link path above obstacles so there is some flexibility in installing the system.
A wireless bridge uses WiFi technology but as a point to point system with high gain directional antennas. If using the 5GHz band there is less interference although there is also less penetration of walls or other clutter (trees). A 2.4GHz wireless bridge is best where some clutter exists. The wireless bridge is essentially a cable through the air and does not suffer from the same issues as WiFi on the intercom.
Here is a diagram showing a customers recent requirements. Note that the customer already had an electric gate with power and a 7″ Android Touch panel in use for their air-conditioner control. With this system the Android panel had a new intercom App installed and became the indoor station for the intercom system.
The electrician supplied the utility box and power and installed the intercom system and wireless bridge with our guidance. The costs were minimal in comparison with excavation of the driveway and front yard and laying of conduit and cable. The system is expandable by adding a poe switch in the utility box and adding additional cctv cameras to cover inside and outside the yard.
If you are interested in a similar system please contact us for a no obligation discussion of your requirements.