Communication on mines is often impeded by the large areas over which the mining operations are spread. Added to that, cellular signals are often patchy in the absence of sufficient tower coverage. Two-way radios provide a cost-effective and, generally, reliable means of communicating with employees.

“The rub, though, is that the Received Signal Strength Indication (RSSI), which is a direct indication of signal performance, is negatively affected by extremes in temperature. Since many mines are located in remote, extremely hot and humid areas, this can pose a major problem for effective, uninterrupted communication. A receiver is rated for a certain sensitivity, and if thermal noise exceeds it, you will have a reduction in signal-noise ratio as thermal noise contributes to the overall noise floor,” says Sean Mervitz, Sales Manager at Global Communications an Elvey Group company and part of the Hudaco Group of companies), Kenwood’s distributor for Sub-Saharan Africa.

“In fact, in research published in the Proceedings of the Federated Conference on Computer Science and Information Systems, there is a clear relationship between temperature and signal strength. In general, when temperature rises signal strength (RSSI) falls,” he adds.

Selected two-way radios from the Kenwood NX1000 range are now offered by Global Communications with an unprecedented five-year warranty (subject to terms and conditions). These radios have been subjected to arduous temperature conditions and have been proven to successfully and reliably operate at temperatures as low as -30°C and up to temperatures as high as a sweltering +60°C.

Global Communication has deployed these radios on a number of large South African mines and the feedback on their performance has been extremely encouraging. “Given the fact that the repeaters are also placed in a metal housing, which naturally increases the ambient temperature, it’s very heartening that we have not had one failure to date. Perhaps a good way of illustrating performance is to consider the radios we have provided to the South African National Defence Force who protect the national borders around the Kruger National Park whilst also supporting the SAN Parks game rangers in their vital operations against rhino poachers crossing into the park from Mozambique. Heat is a large factor in this environment with temperatures regularly soaring into the mid-forties,” says Mervitz.

Read more the NEXEDGE system deployed in the park. https://www.globalcomms.net/news/kenwood-nexedge-protecting-borders-and-wildlife-at-kruger-national-park

On the opposite end of the scale, in April 2015, adventurer Sean Wisedale relied on the Kenwood Nexedge radios to provide a vital communication tool in the high-altitude rescue of one of his Sherpa crew – Angkami Sherpa in the freezing conditions on Mount Everest.

According to Wisedale: “Angkami Sherpa was airlifted from 6 300 metres after he fell and fractured his leg. Rob Bentley – Base Camp manager and Pasang Sherpa – Nepalese Liaison Officer were in constant communication (using the Kenwood radios) and successfully coordinated a risky high-altitude rescue from Base Camp.”

For more information contact Global Communications, +27 (0) 12 621 0400, info@globalcomms.net, www.globalcomms.net