On 2/6/15 11:32 AM, Donn Lasher wrote:

Properly engineered, however, is the key. Make sure whom-ever is building your links looks at vendor specs, builds a real link budget (including losses from connectors, cable, grounding, etc) properly weather seals everything, and try to get at least a a 20db fade margin if you can. If the things I just mentioned are confusing to your RF guy, you might want to get outside help.

Make sure they can know the models for propagation as well. At lower bands fading caused by K factor change can be a bitch and is the predominant mode of fading. on the higher bands (>11GHz) rain fade is the predominant mode of fading. If you want your network to have 99.999% uptime, the links need to be engineered for 99.9999% uptime. Make sure the consultant knows Pathloss5 and is not using a vendor's program for that (orthogon/motorola/cambium/whatever they call them now) loves to push their own shitty program. If you're using a dynamic data rate radio (most are), ensure you engineer for highest data rate you need. If you run the calcs and it shows 99.9999999% at bfsk but you need 128qam to get your full data rate, what good is it? congestion do to link down modulation is still an outage. -- Bryan Fields 727-409-1194 - Voice 727-214-2508 - Fax http://bryanfields.net