Abstract: The invention provides a method of manufacturing piezoelectric wafers of surface acoustic wave (SAW) identification tags. In one embodiment, the method includes: (1) using a master reticle to form, on each of the piezoelectric wafers, wafer-independent patterns that encode digits of a first significance for SAW identification tags; and (2) using different ones of a library of coding reticles to form, on each of the piezoelectric wafers, wafer-dependent patterns that encode digits of a second significance for SAW identification tags.

Abstract: The present invention provides a system for avoiding code collisions from multiple SAW identification tags and a method of operating such system. In one embodiment the invention provides for (1) focusing an interrogation pulse to within a defined space; and (2) discriminating between coded responses returned from tags located within such defined space.

Abstract: A surface acoustic wave (SAW) identification tag and methods of operating and manufacturing the tag. In one embodiment, the tag includes: (1) a piezoelectric substrate having a SAW transducer located thereon, (2) a group of slots arranged by both pulse position and phase position on said substrate; and (3) a number of reflectors distributed among the slots such that the reflectors encode a number by both pulse position and phase position.

Abstract: A unidirectional transducer for a surface acoustic wave (SAW) device. In one embodiment the device includes (1) a defined area on a piezoelectric substrate within which is located an open circuit reflector perpendicular to the SAW direction of propagation; and a pair of low reflectivity transducer electrodes located within the defined area and connected to opposing bus bars, the electrodes perpendicular to the direction of the SAW propagation and positioned with the excitation center of the pair of electrodes located about seven-eighths of a Rayleigh wavelength at a center frequency of the SAW from the reflector.

Abstract: Surface acoustic wave (SAW) identification tag discrimination methods including, in one embodiment (1) detecting a signal emanating from an electronic device operating within a SAW tag frequency band; (2) identifying a null period in a transmission pattern in the signal; and (3) effecting communication of information during the null period.

Abstract: A method of accommodating code collisions from multiple SAW identification tag coded response pulses. In one embodiment, the method includes: (1) separating probable candidates by time-domain; (2) classifying the probable candidates by code-division separation; (3) employing known coded identification signals to adjust the probable candidates; and (4) correlating the multiple SAW identification tag coded response pulses to identify the probable candidates for further processing.

Abstract: A system for discriminating between coded responses from multiple SAW identification tags and a method of operating such system. In one embodiment the system provides for a SAW tag reader subsystem that detects coded responses from the tags to an interrogation pulse; and a coded response analyzing subsystem, coupled to the SAW tag reader subsystem, that employs signal processing techniques to separate portions of the coded responses and generates possibilities for remaining portions of the coded responses.

Abstract: The present invention provides a system for discriminating between coded responses from multiple SAW identification tags and a method of operating such system. In one embodiment the system provides for (1) a SAW tag reader subsystem that detects coded responses from the tags to an interrogation pulse; and (2) a coded response analyzing subsystem, coupled to the SAW tag reader subsystem, that employs signal processing techniques to separate portions of the coded responses and generates possibilities for remaining portions of the coded responses.

Abstract: A transfer function system for determining an identifier on a surface acoustic wave (SAW) identification tag and a method of operating the same. In one embodiment the system provides for (1) generating a radio frequency (RF) interrogation signal that causes a transducer located on a piezoelectric substrate to produce an initial acoustic pulse that reflects off of a plurality of reflectors arranged according to time and phase position on the substrate to yield response acoustic pulses, the transducer generating an RF response signal from the response acoustic pulses; and (2) determining the identifier by decoding the RF response signal in view of predefined time, phase and amplitude parameters.

Abstract: A surface acoustic wave (SAW) identification tag having a coded transducer and methods of operating and manufacturing the tag. In one embodiment the tag includes: (1) a piezoelectric substrate having a number of reflectors distributed among a group of slots arranged by both pulse position and phase position on the substrate for encoding a number by pulse and phase position; and (2) a SAW transducer located on the substrate for generating a coded interrogation pulse.

Abstract: The present invention provides a system for discriminating between coded responses from multiple SAW identification tags and a method of operating such system. In one embodiment the system provides for (1) a SAW tag reader subsystem that detects coded responses from the tags to an interrogation pulse; and (2) a coded response analyzing subsystem, coupled to the SAW tag reader subsystem, that employs signal processing techniques to separate portions of the coded responses and generates possibilities for remaining portions of the coded responses.

Abstract: The present invention provides a system for avoiding code collisions from multiple SAW identification tags and a method of operating such system. In one embodiment the invention provides for (1) focusing an interrogation pulse to within a defined space; and (2) discriminating between coded responses returned from tags located within such defined space.

Abstract: The present invention provides a system for avoiding code collisions from multiple SAW identification tags and a method of operating such system. In one embodiment the invention provides for (1) focusing an interrogation pulse to within a defined space; and (2) discriminating between coded responses returned from tags located within such defined space.

Abstract: The present invention provides for a propagated signal using multiple pulse per group keying and a method of using the same. In one embodiment the propagated signal includes: (1) an element of data contained within a time period of the propagated signal, the time period divided into a group of time slots; and (2) multiple pulses distributed in a predetermined manner among the time slots by pulse group keying to encode the data.

Abstract: The present invention provides for a propagated signal modulated by phase and time shift keying and a method of using the same. In one embodiment the propagated signal includes: (1) a period of time spanned by a pulse, the period of time divided into a group of time slots, each of the time slots having a unique phase/time position; and (2) the pulse encoding a data element by the phase/time position.

Abstract: The present invention in one embodiment provides for a propagated signal of (1) a time period divided into a group of time slots each having a unique phase/time position; and (2) multiple pulses distributed among the time slots encoding a data element by such unique phase/time position.

Abstract: An object-naming network infrastructure and a method of responding to queries for object names. In one embodiment, the infrastructure includes: (1) a central object name server coupled to a computer network and constituting a first hierarchical level and (2) peripheral object name servers coupled to the computer network and constituting a second hierarchical level, the central object name server responding to an object name query received from a querying system by directing the querying system to query instead one of the peripheral object name servers in the second hierarchical level, the one of the peripheral object name servers either responding to the query with an object name or directing the querying system to query instead further peripheral object name servers constituting a third hierarchical level.

Abstract: The present invention provides for a surface acoustic wave (SAW) identification tag reader and for methods of operating and manufacturing the same. In one embodiment, the SAW identification tag reader includes: (1) a transmitter capable of sending an interrogation signal that excites a SAW transducer located on a piezoelectric substrate, the piezoelectric substrate having a group of slots arranged by both pulse position and phase position, and a number of reflectors distributed among the slots such that the reflectors return to the transducer a return signal containing a number encoded by both pulse position and phase position; and (2) a receiver for detecting the return signal and decoding the number.

Abstract: A surface acoustic wave (SAW) identification tag and methods of operating and manufacturing the tag. In one embodiment, the tag includes: (1) a piezoelectric substrate having a SAW transducer located thereon, (2) a group of slots arranged by both pulse position and phase position on said substrate; and (3) a number of reflectors distributed among the slots such that the reflectors encode a number by both pulse position and phase position.