That would depend on the frequency. All coaxial cables including radiax type cables have specific attenuation loss figures per 100 feet published...You need to determine the initial power, the amount of loss allowed before re-amplifying, then the amplifier gain added and losses to the next hop. The other parameter is how much energy you need outside the cable for how far as this will determine the initial launch power needed.
It is all a mathematical balance based on needed signal and loss in cable vs gain of the amps... I do not think there is one answer.... Cable diameters are also chosen based on acceptable loss per mile/km. These are all engineering choices, not cast in stone.. Doug KD8B At 08:08 AM 2/16/2009, you wrote: >Dear all, >I am a student currently researching on radiating leaky coaxial cables. >I do understand that in long tunnels where radiating leaky coaxial >cables are used, repeaters are placed at various points of the cable. > >I want to know what is the average distance between the repeaters. >I will be glad if somone tell me or share a link with information as >regards to this. > >I will also like to know the acceptable signal degradation per km? >for example is it 15dB/km or 13dB/km? > >Thanks in advance. >Bansoboy. > >
