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.The FDR measurement technique requires a swept frequency input to the transmission line.An inverse FFT (Fast Fourier Transform) is performed on the reflected signals transforming this information into the time domain.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.
Anritsu Handheld products incorporating DTF include tables of many standard cables and waveguides to simplify DTF measurements. If this specification is not available, it can easily be determined by measuring a known length of cable.For example, connector corrosion can be detected early and weather seals replaced before moisture destroys expensive cables.DTF finds these problems because the FDR technique can accurately detect very small performance changes within the transmission line.These common problems can cause unwanted signal reflections.
Poorly tightened connectors and poor environmental seals are exacerbated by acid rain corrosion.
In a Wireless Communication System, tower mounted transmission lines and cables are replaced frequently, perhaps every five to ten years, in some cases.