One of BFR Digital’s specialised areas of expertise is the transmission of composite video over fibre-optic cables. The company says with the introduction of video over IP it started to look for a partner that could provide it with product as robust as its own.
BFR Digital: “Our products are designed and manufactured for real-world field applications. For instance, a close circuit camera installed on a perimeter fence is a simple, common application, but let us take a closer look at the environment. Typically, we install our fibre-optic transmitter in a field enclosure on the same pole as the camera. The temperatures within this field enclosure range for -20 to 70°C but the challenge does not end there. Because the camera is installed on the perimeter, usually in very close proximity to an electric fence, our equipment must also offer resistance to EMI. The last thing an end-user wants is a poor quality image because of interference.
“We set out on a mission to find product as hardy as our own and being an engineering company, we set up a simple bench test to subject hardened Ethernet devices to these extreme conditions. This is how we went about it.
“We set up three different environments; the first was very hot, second was extreme EMI, and last came the very cold environment. The very hot was simple; we purchased a standard off-the-shelf oven and modified it to operate at a constant 70°C. The EMI test was a little more difficult; we configured a car’s coil to continuously arc across a 10 mm gap. The third was simple; we put dry ice in an enclosure and achieved a temperature of -16°C. With these harsh conditions set-up, we needed a continuous data source – what better than streaming video?
“We connected a composite video camera to a video streamer; a device that converts the composite video image to a digital format suitable for streaming over an IT network infrastructure. The output of the video streamer was then fed through an Ethernet switch which was placed in the modified convection oven at 70°C. Out of the oven and in to another switch placed in our EMI enclosure housing the car’s coil that was arcing continuously across its 10 mm gap. Then, out of the EMI enclosure and into the cold where a third switch was operating at -16°C. Out of the cold enclosure the video was streamed into a PC for display. (Visit http://www.bfrdigital.co.za/switches.html to view the experiment.)
“Of the equipment that we tested, EtherWAN proved to be the best performing hardened Ethernet switch under the conditions. Subsequent to our bench experiment EtherWAN has supplied a solution for the Mt. Fuji Weather Station in Japan, which convinced us that we had found the range of Ethernet products we were looking for to support our offering.”
Rising to an altitude of 3776 metres, Mt. Fuji is Japan’s highest mountain. For many years, the Mt. Fuji Weather Station located at its summit has played a significant role as a base for weather observation. In recent years, the station has been made available for use by general scientists; this has led to a host of new research taking advantage of the benefits of Mt. Fuji’s high attitude. Meteorological data at the summit is collected automatically by the meteorological equipment installed in the weather station.
New weather observation infrastructure will be used to connect remote web cameras and detectors, to gather sensor data, process it and distribute reports of current weather at the Mt. Fuji station to a worldwide weather information network.
The weather observation infrastructure structure is used to connect remote web cameras and detectors to gather sensor data, process it and distribute reports of current weather at the Mt. Fuji station to a worldwide weather information network. The new system was integrated with existing weather sensors and data collection systems within Mt. Fuji. A reliable network environment was required to connect the field meteorological equipment to a centralised workstation.
Reliability of the networking equipment was of priority, as all data transmission relies on the network. Equipment needs to remain resistant to the severe climatic conditions, where the average temperature is -15°C and wind speeds reach 15 m/sec. In some areas, the geographic conditions did not allow fibre-optic cable installation, the only available communication line was a phone wire buried a long time ago. However, Ethernet transmission could not be compromised.
Sensors and data acquisition devices were installed on utility towers; signals are converted to IP and then transmitted to a remote centralised room. In between, the EL900 hardened media converter was chosen for fibre-optic connections connected to a hardened unmanaged switch. Data is then transmitted to a local control, via phone wire, using EtherWAN’s ED3141 hardened Ethernet Extender.
A complete networking structure was built with EtherWAN’s hardened unmanaged and managed switches and media converters to provide a realtime weather observation system. EtherWAN also provided a rack-mount commercial grade managed switch, EX3224 (with 24 fibre-optic connections) located in the local IT room aggregating the remote connections and connecting monitoring stations. The use of the EX3141 hardened Ethernet Extender over phone wire, provided the low cost alternative the solution providers were looking for to realise the network requirements.
As a leader in locally designed and manufactured fibre-optic and UTP transmission equipment, BFR Digital says that with EtherWAN it is now even better able to link up South Africa’s most sophisticated CCTV networks.
For more information contact BFR Digital, +27 (0)11 786 5575, brunof@bfrdigital.co.za, www.bfrdigital.co.za
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