It is much less expensive to monitor individual transmission lines for slight degradation and fix the problem early, before serious damage occurs. Transmitter performance is optimized by eliminating poorly performing components. Hand off anomalies are reduced by eliminating ping-ponging between weak/strong base stations.Preventative maintenance has another set of benefits even more important than cost. Overall quality is improved giving greater customer satisfaction.Sunlight exposure can change the dielectric properties of the antenna housing, causing the antenna bandwidth to drift.Antennas and transmission lines used on-board ships and aircraft may be degraded due to salt water corrosion.Eventually these problems cause intermittent outage and failures at exactly the times they are least welcome, such as during storms or during extreme periods of cold.With DTF available, the root causes of RF problems can be identified.
An inverse FFT (Fast Fourier Transform) is performed on the reflected signals transforming this information into the time domain.
The FDR technique uses a swept RF signal instead of TDR DC pulses.
FDR is far more sensitive than TDR and can precisely locate faults and degradation in system performance, not just DC open or short circuit conditions.
In a Wireless Communication System, tower mounted transmission lines and cables are replaced frequently, perhaps every five to ten years, in some cases.
Usually, all the site’s cables are replaced based upon the assumption that maintenance calls are imminent on other feeds in addition to the problem cable.
For the majority of transmission lines and antennas, the absence of DTF capability severely impacts the time to repair transmission lines and renders preventative maintenance procedures impractical.