Abstract: An RFID system using encoded digital information utilizing pulsed linear frequency modulation (LFM). The LFM waveform is sent from an24 aircraft or satellite and is received by a transponder. The LFM waveform is demodulated using both, an AM and an FM receiver. The demodulated data is compared to preprogrammed criteria tables, and after validation is decoded and utilized. Algorithms in the transponder are used to determine the frequency deviation and for calculating the direction of the slope of the LFM input signal. The valid RF signal is stored in a delay element, encoded with the transponder data using phase modulation (PM), and frequency modulation (FM). The tag transmission is synchronized to the input LFM waveform. The transmit/receive chopping signal prevents unwanted oscillations and is capable of randomization.

Abstract: An RFID system using encoded digital information utilizing pulsed linear frequency modulation (LFM). The LFM waveform is sent from an aircraft or satellite and is received by a transponder. The LFM waveform is demodulated using both, an AM and an FM receiver. The demodulated data is compared to preprogrammed criteria tables, and after validation is decoded and utilized. Algorithms in the transponder are used to determine the frequency deviation and for calculating the direction of the slope of the LFM input signal. The valid RF signal is stored in a delay element, encoded with the transponder data using phase modulation (PM), and frequency modulation (FM). The tag transmission is synchronized to the input LFM waveform. The transmit/receive chopping signal prevents unwanted oscillations and is capable of randomization.

Abstract: A method for accounting for individual ones of a plurality of items based upon random times that occur as a function of a first specified time interval, and a random interval inventory system that operates in accordance with the method. The method includes a first step of transmitting information signals based upon random times from individual ones of a plurality of tags (5a1-5xx) to at least one of at least one master transceiver and at least one transceiver (4a-4n). The individual tags (5a1-5xx) are affixed to respective individual ones of a plurality of items. The information signals transmitted from each tag (5a1-5xx) correspond at least to the respective item to which the tag (5a1-5xx) is affixed. The random times occur as a function of a first specified time interval.

Abstract: A method for accounting for individual ones of a plurality of items based upon random times that occur as a function of a first specified time interval, and a random interval inventory system that operates in accordance with the method. The method includes a first step of transmitting information signals based upon random times from individual ones of a plurality of tags (5a1-5xx) to at least one of at least one master transceiver and at least one transceiver (4a-4n). The individual tags (5a1-5xx) are affixed to respective individual ones of a plurality of items. The information signals transmitted from each tag (5a1-5xx) correspond at least to the respective item to which the tag (5a1-5xx) is affixed. The random times occur as a function of a first specified time interval.