Using the somewhat old-fashioned coaxial cable to transmit digital signals from network cameras may sound illogical. However, this can be an excellent solution in practice.
Until 1990, data traffic between computers was transmitted via coaxial cables. The signals from analog security cameras were also typically transmitted through this cable network. Nowadays, many analog cameras are being replaced with digital versions, network cameras. These cameras transmit their digital signals over network cables, either directly to a recorder or to a switch in the network. When you replace an analog camera system with a digital one, you would typically need to replace both the cameras and the cabling. At least, that seems like the most straightforward solution.
However, that’s not always necessary. There are two reasons why it can sometimes be better to reuse the existing coaxial cabling for transmitting digital camera signals. This is known as ‘IP over coax.’
Achieving cost savings
The first reason is the cost of replacement work. If the cables are laid through complex cable trays, embedded in walls or floors, or buried underground, the total replacement cost could be quite high. This is true even though network cables are cheaper than coaxial cables.
For IP over coax, you will need converters on both ends of the coaxial cable. These convert the network signal into a format that can be transmitted over the 2-wire coaxial cable. This technology isn’t new. Internet providers have been using it for years to transmit TV and internet signals to homes. However, while this involves just one connection, a camera system often requires multiple connections. This means you’ll need multiple converters or multi-converters, which brings extra costs. You should consider whether these costs outweigh the expense of replacing the coaxial cabling.
When distance poses a problem
The second reason to reuse the existing coaxial cabling is that network cables can only cover a limited distance. If the distance is greater than 100 meters, network cables are no longer suitable. With coaxial cables, you can cover long distances – up to 1,500 meters – in one go. If such long distances are involved, keeping the coaxial cabling is definitely the better option. In this case, the decision isn’t driven by cost, but because IP over coax is simply the right solution. You should be aware that converters for these long distances require power, sometimes on both ends. Fortunately, analog cameras were often powered locally, so this shouldn’t be a problem. With the right converters, your new cameras can also be powered using Power over Ethernet, or more accurately, Power over Coax.
Coax – not such a bad option after all
Therefore, it’s not always necessary to replace existing coaxial cabling when switching to a digital camera system. The total replacement cost or the distances to be covered may be reasons to reuse the coaxial cabling. Of course, this is only possible if the existing cabling is still in good condition. Additionally, there should be no analog amplifiers used in the connection IP over coax can be cost-effective and, in some cases, is even a necessary solution due to the long distances that need to be covered. Reusing an existing infrastructure that is still in good condition is also better for the environment.