System for communicating with electronic equipment

A system for communicating information on a network having a piece of equipment connected thereto over data lines normally carrying high frequency data communications, said system comprising:

• a central module including a signal receiver and a signal demodulator;
• at least one remote module associated with a piece of equipment, said remote module including:
• a signal modulator and a signal transmitter for transmitting a modulated signal having a bit rate over the data lines;
• wherein said signal receiver and signal demodulator in the central module serve to receive and demodulate the modulated signal to detect information sent from the remote module over the same data lines without disturbing normal network high frequency data communication;
• and
• wherein said system further comprises a blocking circuit coupled to the data lines for selectively disabling communication by the associated piece of equipment to the network.

A system for communicating information on a network having a plurality of electronic equipment connected thereto over data lines normally carrying high frequency information, said system comprising:

• a central module including:
• a first power source for coupling a signal to the data lines;
• and
• a signal demodulator;
• a plurality of remote modules, one remote module being connected to each piece of equipment, each remote module including a signal modulator for modulating the signal from the first power source at a predetermined bit rate and returning a modulated signal to the data lines;
• said signal demodulator in the central module demodulating the modulated signal to detect information sent from each remote module on the network without disturbing normal network high frequency data communication;
• and
• wherein said system further comprises a blocking circuit coupled to the data lines for selectively disabling communication by a selected piece of equipment to the network.

A system for communicating information on a network having a plurality of electronic equipment connected thereto over data lines normally carrying high frequency information, said system comprising:

• a central module including:
• a source for supplying DC power;
• a power modulator for modulating the supplied DC power and transmitting a modulated power signal to the data lines;
• a signal receiver having an interface amplifier connected to the data lines;
• and
• a signal demodulator connected to the signal receiver;
• a blocking circuit connected to the data lines for disabling communication by the associated piece of equipment;
• a remote module connected to an associated piece of equipment, said remote module including;
• a signal modulator having:
• a resistor network;
• and
• a fixed frequency encoder for generating encoded signals connected to the resistor network, said resistor network connected between the data lines for coupling a modulated signal representative of the encoded signals to the data lines;
• a power demodulator for demodulating the modulated power signal to detect information sent from the central module to the associated piece of equipment without disturbing normal network high frequency communication;
• and
• a voltage regulator for filtering the supplied power from the source;
• wherein said central module signal demodulator serves to demodulate the modulated signal sent from the remote module to detect information sent from each piece of equipment on the network without disturbing normal network high frequency communication.

A system for communicating information on a network having pieces of electronic equipment associated therewith, said system comprising:

• a central module including a receiver;
• remote modules connected to the pieces of equipment, each remote module including a transmitter for transmitting multi-bit information to the receiver, the information being a unique identification signal related to the piece of equipment to which each module is associated, and wherein the bit rate of the multi-bit information is less than about 1% of the bit-rate of the high frequency data communication,
• a database having information that identifies each piece of equipment and its location on the network, along with an identification signal for each piece of equipment provided by its associated remote module;
• wherein the system periodically updates the database as a function of the identification signals transmitted by the remote modules to thereby track the identity and location of the equipment on the network;
• wherein the multi-bit information is transmitted from the remote module to the receiver over a network cable that also normally carries high frequency data communications over the network to the electronic equipment;
• the central module including a first power source for supplying power to the remote modules and further includes a second power source for coupling a current to wires in the network cable;
• wherein the transmitter in the remote module transmits a variable impedance across the wires in the network cable at a predetermined bit rate such that the multi-bit information is embedded into the current from the second power source;
• and
• wherein the current returns to the central module and the receiver therein detects the multi-bit information embedded in the current received from the remote module over the same network cable.