Abstract: The communication system comprises amplification units coupled to the radiating transmission line at periodic locations for amplifying communication signals radiating and traveling upstream and downstream on the transmission line. During normal operation, mobile communication units near the radiating transmission line can communicate with other mobile communication units near the transmission line as well as with a base station by transmitting communication signals at a first and second frequency. The amplification units also comprise degradation detection units which detect when the communication system has been degraded between any two amplification units. Upon detection of a degradation, the amplification units commence to amplify, transmit and receive the communication signals across the location of the detected degradation at a first fault frequency and a second fault frequency, rather than the first frequency and second frequency, respectively.

Abstract: A radio frequency communication system utilizing a radiating transmission line for communicating data signals is disclosed. The data signals convey digital data to remotely located data devices, including computers, equipment control systems and digital video cameras. The data signals have a wide bandwidth of about 0.5 MHz to 32 MHz. In this way, the communication system creates a local area network by means of the radiating communication line. The communication system is intended to be used in environments where radio waves do not propagate well, such as in underground environments, and in particular mines. The communication system comprises at least one amplifier connected to the radiating transmission line for periodically amplifying the data signals by demodulating the data signals to recover the data contained therein and then modulating the recovered data into a regenerated radio frequency at a power level permitting transmission and radiation of the regenerated radio frequency data signal.