Energy distribution and communication system and method utilizing a communication message frame for a multi-device vehicle occupant protection system

An occupant protection system for protecting a vehicle occupant, said system comprising:

• an actuatable occupant protection device for protecting the vehicle occupant;
• a central unit for controlling actuation of said protection device and for providing power for use by said protection device, said protection device being located remote from said central unit;
• and
• an electrical conductor interconnecting said central unit and said protection device for conducting electrical energy;
• said central unit including energy supply means for providing electrical energy, having a voltage, onto said conductor;
• said central unit including voltage messaging means for adjusting voltage of the electrical energy past a predetermined threshold to provide a message frame and for modulating voltage of the electrical energy during the message frame to convey messages from said central unit to said protection device via said conductor;
• said protection device including voltage receiver means for monitoring the voltage of the electrical energy during the message frame and for detecting the voltage modulations to discern messages from said central unit;
• said protection device including current messaging means for modulating current of the electrical energy during the message frame to convey messages to the central unit via said conductor, including means for utilizing the modulation of voltage of the electrical energy to clock current modulation;
• and
• said central unit including current receiver means for detecting current modulations to discern messages from the protection device.

A method of distributing energy and communicating between a central unit and a plurality of remote units, said method comprising:

• providing electrical energy, having a voltage, onto a conductor from the central unit to power the remote units;
• adjusting the voltage of the electrical energy past a predetermined threshold to provide a message frame;
• modulating voltage of the electrical energy during the message frame to convey messages from the central unit to the remote units;
• detecting the voltage modulations at the remote units to discern messages from the central unit;
• modulating current during the message frame to convey messages from the remote units to the central unit;
• and
• detecting the current modulations at the central unit to discern messages from the remote units;
• wherein said step of modulating current includes utilizing the modulation of voltage of the electrical energy to clock modulation of current.

An energy distribution and communication system between a central unit and a plurality of remote units, said system comprising:

• an electrical conductor interconnecting the central unit and the remote units for conducting electrical energy;
• energy supply means for providing electrical energy, having a voltage, onto said conductor to power the remote units;
• voltage messaging means, associated with the central unit, including means for adjusting voltage of the electrical energy to remain past a predetermined threshold to provide a message frame and means for modulating voltage of the electrical energy, without the voltage of the electrical energy proceeding past the threshold, during the message frame to convey messages from the central unit to the remote units via said conductor;
• voltage receiver means, at each remote unit, including means for monitoring the voltage of the electrical energy during the message frame and means for detecting the voltage modulations to discern messages from the central unit;
• current messaging means, at each remote unit, for modulating current of the electrical energy during the message frame, and concurrent with the modulation of voltage of the electrical energy, to convey messages to the central unit via said conductor, including means for utilizing the modulation of voltage of the electrical energy to clock current modulation;
• and
• current receiver means, associated with the central unit, for detecting current modulations to discern messages from the remote units.