Ethernet isolator for microphonics security and method thereof

Abstract

A system and method for providing microphonic isolation on a transmission line. The transmission line has a first part and a second part. The first part of transmission line carries a data signal and a microphonic signal. The microphonic signal has frequencies that include those in a range of substantially 20 Hz to substantially 20 kHz. The system includes an isolation apparatus. The isolation apparatus has an input in electrical communication with a first part of the transmission line, an output in electrical communication with the second part of the transmission line, and a filter in electrical communication with the input and the output. The filter is arranged to substantially remove the microphonic signal received at the input from first part of transmission line and pass the data signal to the output.

1 . A method for providing microphonic isolation on a transmission line, the transmission line having a first part and a second part, the first part of the transmission line carrying a data signal and a microphonic signal, the microphonic signal having frequencies that include those in a range of substantially 20 Hz to substantially 20 kHz, the method comprising:
 receiving the data signal and the microphonic signal from the first part of the transmission line;   substantially removing the microphonic signal received from the first part of the transmission line using an isolation apparatus having a filter; and   outputting the data signal on the second part of the transmission line.   
     
     
         2 . The method according to  claim 1 , wherein the transmission line is an Ethernet transmission line. 
     
     
         3 . The method according to  claim 2 , wherein the isolation apparatus substantially removes the microphonic signal at least in part by optically isolating the first part of the transmission line from the second part of the transmission line. 
     
     
         4 . The method according to  claim 2 , wherein the filter is a high pass filter. 
     
     
         5 . The method according to  claim 2 , further comprising preventing the data signal from being output when the isolation device is not powered. 
     
     
         6 . The method according to  claim 5 , wherein the data signal is prevented from being output when the isolation device is not powered by using a signal interrupt mechanism to disconnect an electrical signal path from the first part of the transmission line to the second part of the transmission signal line. 
     
     
         7 . The method according to  claim 6 , wherein the signal interrupt mechanism is a relay. 
     
     
         8 . The method according to  claim 6 , wherein the relay is energized based on a power signal received from an electronic device, the electronic device transducing the microphonic signal.