What is the maximum recommended length for an antenna cable connected to your wireless modems?If you want a simple answer, you should try to keep the cable under 10 feet.
In reality, there is not a simple answer to the question. The maximum length depends on the attenuation characteristics of the cable, the frequency band in use, and the local received signal strength.
Here is a rough example. Assume there is about 40dB variation in signal strength between maximum and minimum signal levels encountered in the field. One hundred feet of a typical coaxial cable might have 40dB of loss, so if you are located very near the base station, you could use a 100' cable and just get by. If your received signal strength is weaker, then you would need to shorten your cable.