Amtech Corporation

Amtech Technology Corp.

The United States of America As Represented by the United States

Intermec IP Corporation

Jeremy A Landt

Alfred R Koelle

Donald F Speirs

David A Eckhardt

Curt L Carrender

Curtis Lee Carrender

Richard L Veghte

G Russell Mortenson

Vickram Sondhi

Ivan Berka

An apparatus for object identification including a multi-meter terminal having a plurality of data modules, a triggering device for initiating one of the plurality of data modules to retrieve object identification data from an object, a radio module for downloading the retrieved object identification data to a host and a housing containing the data modules, triggering device and the radio module.

Integrated multi-meter and wireless communication link

A method and apparatus for object identification which includes a portable electronic tag reader having a transceiver capable both of reading identification information from electronic tags and transmitting collected information to a base unit for remote analysis. The system of the present invention utilizes the same transceiver to receive information from the base unit and write data to read/write electronic tags. The system of the present invention includes a transceiver for generating a modulated or unmodulated radio frequency interrogation signal, a receiver for detecting a return signal from an electronic tag and a signal processor for processing the return signal. A modulator within the portable unit combines the identification data with the radio frequency interrogation signal for transmission to a base unit through a wireless local area network. A demodulator within the portable unit extracts data and commands received from a base unit for local processing or transfer to a read/write electronic tag. In one embodiment, the portable electronic tag reader includes a user interface for initiating commands and a user display for displaying status information associated with the reading, downloading, or uploading processes.

Integrated electronic tag reader and wireless communication link

A reader interrogates a transponder attached to a remote object. The transponder includes a microstrip patch antenna having two segments connected together by a switch, each segment being one-half wavelength, the antenna being a full wavelength at the frequency of the interrogating signal. In response to a control signal, the switch is opened and closed, thereby coupling and decoupling the two segments of the microstrip antenna. When the switch is in the closed position, the two segments are out-of-phase with one another, thereby producing a maximum reflected signal. When the switch is in the open position, the two segments act in concert to produce a minimum backscattered signal. The backscatter signal is thus modulated in accordance with the control signal and is received at the reader where it is subsequently decoded to identify the remote object.

Transponder employing modulated backscatter microstrip double patch

The invention provides a reader-transponder system that prevents reading of undesired transponder signals. The reader generates a low-frequency signal that is used to supply power to the transponder. The same low-frequency signal also is used to generate a clock signal for the transponder. The reader varies the frequency of the low-frequency power signal according to a code that is unique to the reader. Because the transponder clock signal is derived from the encoded low-frequency power signal, it also varies in accordance with the reader's code. The coded transponder clock signal is contained in the modulation of the RF signal produced by the transponder. When the reader receives and decodes the RF signal, it also extracts the transponder clock signal from the received RF signal and compares variations in the extracted transponder clock signal to the code that was applied to the low-frequency power signal transmitted by the reader. If the pattern of variations in the transponder clock signal matches the reader's code, then the reader senses that the RF signal it has received is from a transponder being powered by that reader and no other.

System for preventing reading of undesired RF signals

The subject invention relates to a system for identifying, for writing data into and reading data out of electronic tags which may be attached to moving and moveable objects. An interrogator sends an RF signal to a remote tag, the signal including data intended to be received and stored in the tag. The tag backscatter-modulates the received signal with data temporarily and permanently stored in the tag, including data indicating the identity of the object to which the tag is attached. The interrogator has the capability of (1) recognizing the identity of the tagged object from the returned backscatter-modulated signal and (2) transmitting data to the tag only if it has data to be transmitted to that particular tagged object. This permits data to be selectively transmitted to a tag and received and stored by that tag only after the tag has been identified as a correct one to receive that data. The tag, in addition, may have the capability of increasing its sensitivity to the receipt of transmitted data after receiving a signal from the interrogator of sufficient strength to be capable of transmitting data to that tag.

System for reading and writing data from and into remote tags

Briefly, the range limiting system of the invention is capable of differentiating desired received signals having an amplitude above a predetermined threshold level and at least one other recognizable predetermined characteristic, from other received signals below that predetermined threshold amplitude. The system has a means for combining the received signal, which is of unknown amplitude which may be above or below the predetermined threshold amplitude, with a known signal of the predetermined threshold amplitude having at least one other predetermined characteristic which is distinguishable from the other recognizable characteristic of the received signal. The output of the combining means passes to a signal processing means which produces an output signal whose other recognizable characteristic is determined by the received signal only when the received signal is above the predetermined threshold amplitude, and by the known signal when the received signal is below the predetermined threshold amplitude. The presence or absence of the desired signal is determined on the basis of analysis of the other predetermined characteristic of the output signal of the signal processing means.

Range limiting system

The invention provides a system for discriminating between modulated backscattered signals based upon transmission-to-reception time delay. The system employs a carrier, phase-modulated with a modulating signal, having characteristics which provide unity output when correlated with itself with zero time shift and a substantially lower output level when correlated with itself with a significant time shift. The system works with a backscatter-modulator located a finite distance from the transmitter for receiving and modulating the backscatter of the carrier. A receiver/detector receives and detects the modulated backscattered phase-modulated signal, the detector being phase-sensitive and having as a reference signal the transmitted phase-modulating carrier signal, and having as an input signal the phase modulated backscattered carrier. The detector provides an output signal whose averaged amplitude is substantially dependent upon the degree of phase correlation between the phase of the modulation returned input signal and the reference signal. Finally, the output signal from the detector is selectively processed only when its averaged amplitude is above a threshold level. In a preferred embodiment, the transmitted signal is a spread spectrum signal.

Signal discrimination system

The invention relates to an antenna for receiving and modulating transmitted signals having a very low power density on the order of below 1 watt per meter squared, at a selected center frequency above 2,000 MHz. The antenna uses a folded planar dipole section having two separated oppositely disposed U-shape elements, each of said elements having a pair of ends. A capacitor is series-coupled between two of the oppositely disposed ends of the elements, and a diode having a high impedance at the selected center frequency is series-coupled between the other two oppositely disposed ends of the U-shape elements. A metallic backplane is mounted parallel to the planar folded dipole section and spaced from the dipole section a predetermined distance selected to reduce the antenna impedance. The impedance of the diode, the shape of the folded planar diode section and the predetermined amount of spacing of the backplane from the planar folded dipole section are all selected to increase the d.c. power output of the antenna.

Beam powered antenna

An antenna in a transponder receives signals from a reader, modulates them, and reflects them back to a reader to pass the information contained in the transponder to the reader. The system includes a thin planar dielectric material having first and second opposite surfaces, preferably with the approximate dimensions of a credit card. First conductive material is disposed on the first surface of the dielectric member at a first end of the member. Second conductive material on the second opposite surface of the dielectric member at the second end of the member defines a dipole with the first material. The second material, preferably triangular in configuration, extends from the second end to a median position between the opposite ends. An electrical circuitry module on the dielectric member produces reflected signals modulated at a particular frequency from the signal transmitted by the reader to pass information contained in the transponder to the reader. The third conductive material on the second surface of the member is electrically coupled with the second conductive material and extends from the triangular apex toward the first end to enhance an impedance match between the dipole and electrical circuitry. The third material has a first low impedance portion split into two parts connected in parllel to provide an extended effective length in a relatively small distance, and has a second portion, preferably a 'pigtail', of substantially higher impedance than the first portion connected in series with the first portion.

Transponder antenna

A dielectric member may be thin and planar and may have first and second opposite surfaces. An electrically conductive material is disposed on the first surface at one end of the first surface and an electrically conductive material is disposed on the second surface at the opposite end of the second surface. The conductive materials in the first and second surfaces define a first antenna operative at a first frequency. Slots are provided in the conductive material in the first surface. The slots define a second antenna operative at a second frequency greater than the first frequency. The slots include first and second slots extending in a direction transverse to the relative direction of the conductive materials on the first and second surfaces. The first and second slots may have substantially equal lengths and may be aligned with each other. The slots also include third and fourth slots extending in such relative direction and respectively communicating with the first and second slots. The third and fourth slots are in spaced and parallel relationship to define a conductive portion. The lengths of the first and second slots define the frequency of the signals from the second antenna and the lengths of the third and fourth slots define the impedance of the second antenna. Additional conductive material is disposed on the first surface of the dielectric member in electrical communication with the conductive portion. The additional conductive material is disposed opposite the conductive material on the second surface and is provided with a length defining the impedance of the first antenna.

A reader interrogates an object. The object has a tag with a data source such as a read-only memory (ROM) which produces an identifying sequence of binary 1's and 0's in an individual pattern and transmits these signals to the reader. Each '1' or '0' is converted to a plurality of signal cycles at first and second harmonic frequencies. For example, a '1' may be identified by two signal cycles at the second frequency (e.g. 40 kHz) and then one signal cycle at the first frequency (e.g. 20 kHz) and a '0' may be identified by a signal cycle at the first frequency and then two signal cycles at the second frequency. The transponder also produces a plurality of signal cycles in an individual code (different from any combination of '1's' and '0's') to indicate the end of the transmission of the signal cycles identifying the object and the start of another transmission. The reader receives the signal cycles identifying the object and delays these signal cycles by (a) a first time such as 1/4 period of a cycle at the second frequency, (b) a second time such as 1/2 of such period and (c) a third time corresponding to such period. The reader compares the received signals and the first delayed signals to produce first phase-locked signals. The reader compares the received signals and the second delayed signals to produce additional phase-locked signals at the times that the first phase-locked signals are not produced. The reader then produces clock signals from the first and additional phase-locked signals. The reader produces information signals from a comparison of the received signals and the third delayed signals. The reader synchronizes the information signals with the lock signals to identify the object.

System for identifying particular objects

A homodyne radar transmitter/receiver device which produces a single combined output which contains modulated backscatter information for all phase conditions of both modulated and unmodulated backscatter signals. The device utilizes taps along coaxial transmission lines, strip transmission line, and waveguides which are spaced by 1/8 wavelength or 1/6 wavelength, etc. This greatly reduces costs by eliminating separate transmission and reception antennas and an expensive arrangement of power splitters and mixers utilized in the prior art.

Multichannel homodyne receiver

An instrument is disclosed for mapping vertical conductive fractures in a resistive bedrock, magnetically inducing eddy currents by a pair of vertically oriented, mutually perpendicular, coplanar coils. The eddy currents drive magnetic fields which are picked up by a second, similar pair of coils.

Growing community of inventors

Los Alamos, NM, United States of America

Jeremy A Landt