Patent
Method, system and apparatus for initiating and maintaining synchronization of a pulse position modulation (ppm) decoder with a received ppm signal
Lee Youbok,Lee Furey,William F. Gallagher,Ronald Salesky,Samuel E. Alexander,Inui Shinichiro +5 more
TLDR
In this paper, a radio frequency identification (RFID) tag device having a pulse position modulation (PPM) decoder circuit calculates a relative frequency relationship between an internal clock-oscillator of the tag device and an external PPM source such as a RFID tag reader.Abstract:
A radio frequency identification (RFID) tag device having a pulse position modulation (PPM) decoder circuit which calculates a relative frequency relationship between an internal clock-oscillator of the RFID tag device and an external PPM source such as a RFID tag reader, and then synchronizes the RFID tag device PPM decoder circuit to the required precision for reliable PPM symbol decoding. The PPM decoder is synchronized by measuring the “counts per pulse” (CPP) from a calibration cycle having a plurality of pulses in a single symbol frame.read more
Citations
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Patent
Radio frequency identification architecture
TL;DR: In this article, a radio frequency identification (RFID) architecture is described, where RFID tags are interrogated by a reader, which may be located in a network of readers.
Patent
Mobile RFID reader with integrated location awareness for material tracking and management
Sujeet Chand,Vivek R. Bapat,Kenwood H. Hall,Richard A. Morse,Joseph P. Owen,Arthur P. Pietrzyk,Andreas Somogyi,Kenneth A. Tinnell +7 more
TL;DR: A portable RFID reader (or reader/writer) that also employs a location determination subsystem that facilitates determination of the reader's location can be found in this paper, where the location subsystem can employ a satellite-based GPS (Global Positioning System) location technology where such signals are unimpeded by structures.
Patent
Method, system, and apparatus for remote data calibration of a RFID tag population
TL;DR: In this paper, a method, system, and apparatus for remotely calibrating data symbols received by a radio frequency identification (RFID) tag population are described, where tags are interrogated by a reader, which may be located in a network of readers.
Patent
Method and apparatus for preparing an item with an rfid tag
TL;DR: In this paper, an automated reading system for associating an RFID tag and product information includes a conveyor belt for moving a product having an RIB tag and a bar code.
Patent
Systems and methods that integrate radio frequency identification (RFID) technology with industrial controllers
TL;DR: In this paper, the authors describe systems and methods that provide electronic data (e.g., Electronic Product Code (EPC) data) obtained from Radio Frequency Identification (RFID) tags by RFID readers and/or from servers to one or more industrial components.
References
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Patent
Apparatus and method of use of radiofrequency identification tags
Bruce B. Roesner,Ronald M. Ames +1 more
TL;DR: In this paper, a method of programming or writing to an RFID tag with a transient pulse at both high and low frequencies is described, i.e. in the GHz and KHz ranges.
Journal ArticleDOI
Trellis-coded pulse-position modulation for indoor wireless infrared communications
TL;DR: It is shown that maximum-likelihood sequence detection (MLSD) of trellis-coded PPM is very effective in mitigating the multipath dispersion on indoor, wireless infrared channels.
Patent
Method and apparatus for improving the resolution of pulse position modulated communications between an implantable medical device and an external medical device
TL;DR: In this paper, the phase uncertainty between an external signal and an internal signal is measured by a dual slope circuit that varies a state variable (which can be a digital timer, a capacitor voltage, or the like) with either a positive or negative slope.
Patent
Combined OOK-FSK/PPM modulation and communication protocol scheme providing low cost, low power consumption short range radio link
TL;DR: In this article, a communication system provides robust, short range radio communications between battery operated devices by using ON-OFF-KEYED (OOK) modulation and either frequency shift keyed (FSK) modulation or pulse position/width modulation (PPM/PWM) in combination with a prescribed communications protocol.
Patent
Phase locked loop apparatus for pulse signal demodulation
TL;DR: In this article, a phase relationship between the motion clock and the information pulse to be demodulated is classified into six kinds of patterns, and in case the relationship is outside the patterns, it is to be excluded as being under effect of noise.