ClosedNetworks CEO warns of 4.9 GHz band issues
DENVER–Ed Vea, chief executive officer of ClosedNetworks, tempered the hype surrounding the prospects of the 4.9 GHz band, highlighting the fact that several cost and network considerations come into play that won’t make planning high-speed mobility networks easy.
“I get nervous when I read about a public-safety agency that wants to do mobile broadband that includes video, VoIP and other QoS applications,” said Vea during the APCO session, “Data, Video and Voice Application for 4.9 GHz.” “Their solution is to throw more bandwidth at it. You can’t throw more bandwidth.”
The first consideration for any 4.9 GHz network should be cost, he said. Because of the propagation characteristics of the 4.9 GHz band, a serial data network will require a significant amount of nodes, whether that is on the base station side or client end.
The simplest way to utilize the 4.9 GHz band is to construct a point-to-point link, which allows public-safety entities to save thousands on dedicated T-1 lines, said Vea. Serial data networks require more planning to manage signals because of bandwidth degradation. Metro-wide mesh networks offer some mobility without a true mobile IP core since the points tie back to an Internet cloud, he said. And mobility networks might not be cost effective enough to fill in the coverage holes.
“I get concerned about public-safety saying they want to use this for voice,” said Vea. “Right around the corner there could be a coverage hole. This may be good for hot spots that allow applications such as filing reports, but to really rely on these systems is questionable.”