Wireless, battery-less, asset sensor and communication system: apparatus and method

5- A battery-less sensor for an asset sensing and communication system, said battery-less sensor comprising in combination:

• a transducer operatively coupled to an asset for sensing physical asset parameters and outputting analog signals correlative to said sensed physical asset parameters;
• a coil for receiving a transmitted signal;
• power means connected to said coil for deriving power from said received transmitted signal;
• circuit means, connected to and powered by said power means, said circuit means including sampling means and modulating means;
• said sampling means, connected to said transducer, for sampling and digitizing said analog signals into digitized signals correlative to said sensed physical asset parameters;
• said modulating means, connected to said sampling means and said coil, for modulating said received transmitted signal for transmitting data that is correlative to said sensed physical asset parameters of the asset, and
• wherein said battery-less sensor receives power from said wirelessly transmitted signal for powering said battery-less sensor and modulates said wirelessly transmitted signal with data correlative to said sensed physical asset parameters of the asset.

10- An asset parameter sensing and communication system comprising in combination:

• a reader device comprising in combination:
• means for transmitting a signal through free space;
• means, operatively coupled to said transmitting means, for detecting changes in said transmitted signal, converting said detected changes into digital values and transmitting said digital values to a portable data collector;
• a battery-less sensor comprising in combination:
• a transducer operatively coupled to an asset for measuring physical asset parameters and outputting analog signals correlative thereto;
• means for receiving and deriving power from said transmitted signal;
• means, operatively coupled to both said power deriving means and said transducer, for sampling and digitizing said analog signals into digitized signals correlative to said measured physical asset parameters;
• means, connected to said sampling and digitizing means, for modulating said received transmitted signal as a function of said digitized signals correlative to said measured physical asset parameters for creating a modulated transmitted signal by changing said transmitted signal transmitted from said reader;
• and
• wherein said detecting means of said reader detects and converts said modulated transmitted signal into digital values and transmits said digital values to the portable data collector for further processing.

14- An asset parameter sensing and communication system comprising in combination:

• two tuned coils using an open air interface for transmitting a signal through free space for wirelessly transmitting data correlative to measured physical asset parameters and power across an open air interface, said two tuned coils comprised of a sensor coil and a reader coil;
• a transducer operatively coupled to an asset for measuring physical asset parameters and outputting analog signals correlative thereto;
• means, operatively coupled to said sensor coil, for deriving power from said transmitted signal;
• means, operatively coupled to both said power deriving means and said transducer, for sampling and digitizing said analog signals into digitized signals correlative to said measured physical asset parameters;
• means, connected to said sampling and digitizing means, for modulating said transmitted signal as a function of said digitized signals correlative to said measured physical asset parameters such that said modulating means causes changes in said transmitted signal;
• and
• means, operatively coupled to said reader coil, for detecting said changes in said transmitted signal, converting said detected changes into digital values and transmitting said digital values to a portable data collector for monitoring the asset as a function of said measured physical asset parameters.

17- An asset parameter sensing and communication system comprising in combination:

• a battery-less sensor and a reader device;
• said reader device comprising in combination:
• an oscillator means for creating a time varying waveform having generally a constant frequency;
• a reader coil operatively coupled to said oscillator means for transmitting a signal through free space;
• a demodulator means operatively coupled to said reader coil for detecting changes in amplitude of the said transmitted signal;
• a signal conditioning circuit operatively coupled to said demodulator for transforming said detected changes in amplitude of said transmitted signal a series of digital pulses;
• a first microprocessor operatively coupled to said signal conditioning circuit for converting said series of digital pulses from said signal conditioning circuit into digital words and transmitting said digital words to a portable data collector operatively coupled to said first microprocessor;
• a battery-less sensor comprising in combination:
• a transducer operatively coupled to an asset for measuring physical asset parameters and outputting analog signals correlative thereto;
• a sensor coil for receiving said transmitted signal from said reader coil;
• power means connected to said sensor coil for deriving power from said received transmitted signal;
• circuit means, connected to and powered by said power means, said circuit means including sampling means and modulating means;
• said sampling means, connected to said transducer, for sampling and digitizing said analog signals into digitized signals correlative to said measured physical asset parameters;
• said modulating means, connected to said sampling means and said sensor coil, for modulating said received transmitted signal as a function of said digitized signals for creating a modulated signal transmitting data to said reader correlative to said measured physical asset parameters such that said battery-less sensor employs said transmitted signal for wirelessly receiving power from said reader and wirelessly transmitting information to said reader, and
• wherein said modulated signal causes said changes in amplitude of said transmitted signal which are detected by said demodulator means, transformed by said signal conditioning circuit, converted by said microprocessor, and transmitted to the portable data collector by said microprocessor for monitoring the asset as a function of said measured physical asset parameters.

19- A method for sensing and communicating asset parameters, the steps including:

• mounting a battery-less sensor to an asset for sensing physical asset parameters;
• powering said battery-less sensor by holding a reader device adjacent said battery-less sensor and wirelessly transmitting a signal from said reader device to said battery-less sensor;
• sensing and digitizing physical asset parameters with said battery-less sensor;
• modulating, with said battery-less sensor, said wirelessly transmitted signal as a function of said digitized physical asset parameters;
• transmitting, with said battery-less sensor, data to said reader correlative to said sensed physical asset parameters such that said battery-less sensor is wirelessly powered by said wirelessly transmitted signal from said reader and wirelessly transmits information to said reader by modulating said wirelessly transmitted signal from said reader.