Portable field-programmable detection microchip

• US 5,218,343 A
• Filed: 02/05/1991
• Issued: 06/08/1993
• Est. Priority Date: 02/05/1990
• Status: Expired due to Term

• Current Assignee: Anatoli Stobbe
• Original Assignee: Anatoli Stobbe
• Inventors: Stobbe, Anatoli, Herrmann, Wilfried
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US07/650,490
• Time in Patent Office: 854 Days
• Field of Search: 340/572, 340/505, 340/825.34, 340/870.24, 340/870.31
• US Class Current: 340/573.4
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

A read/write device includes a transmitter for producing an RF signal and a modulator coupled to said transmitter for modulating the RF signal and, finally a data receiver for receiving RF data signals from a portable microchip. The microchip includes a resonant circuit tuned to the RF frequency of the read/write transmitter and a receiver that is coupled to the resonant circuit for detecting the RF signal. There is also provided a charging capacitor capable of storing the electrical energy from the RF signal so that the microchip can be powered during pulse pauses of the RF signal. The microchip includes a memory circuit for storing the identification code of the microchip, and a code generator that is coupled to the memory circuit for generating an RF signal that is modulated with the identification data. A switching element that couples the resonant circuit to the code generator de-tunes the resonant circuit when the identification data is transmitted back to the read/write device. The same resonant circuit also serves to field program the memory circuit of the microchip by receiving pulse pause modulation signals (PPM) of the RF carrier signal thus allowing the identification code of the microchip to be altered by the read/write device.

Claims

1. The combination of a portable, field-programmable detection microchip for storing identification data for identifying persons, animals or objects, and a read/write device for accessing the data stored in the microchip, when brought within RF coupling proximity thereof, the combination defining an identification system comprising:

a read/write device including a transmitter for producing an RF field, a pulse pause modulator coupled to said transmitter for modulating the RF field during the field programming mode, said pulse pause modulator providing different function modes, such as band rate, single-phase modulation, dual-phase modulation, field synchronous and field-asynchronous data transmission, binary format, biphase format, FSK format, FSK frequencies, memory size, read/write mode, read-only mode, said modes being transmitted by said read/write device to the detection microchip via the RF field and a data receiver for receiving RF data signals from the detection microchip; and

a detection microchip including a resonant circuit tuned to the frequency of said RF field, a charging capacitor coupled to said resonant circuit for storing electrical energy during the occurrence of the RF field, and powering said microchip during pulse pauses of the RF field, a signal receiver coupled to said resonant circuit for decoding the modulated RF field, including a decoder circuit, a memory circuit for storing the identification data of said microchip, a code generator coupled to said memory circuit for generating an RF signal modulated with the identification data, an oscillator coupled to both said code generator and said decoder circuit for providing a field-independent time reference to said detection microchip, and switching means coupled to said resonant circuit and said code generator for coupling the identification data from said code generator to said resonant circuit, said switching means changing the impedance of said resonant circuit during the transmission of the identification data, wherein the same resonant circuit is used to provide the energy for the detection microchip, further to transmit data to the read/write device and to receive commands and data for reprogramming from the read/write device.

2. The combination as recited in claim 1, wherein said read/write device additionally comprises means for field programming the memory circuit of said microchip by using said modulator for pulse pause modulating (PPM) said RF field, so that said RF field includes data and command signals for changing the identification data stored in the memory circuit of said microchip.

3. The combination as recited in claim 1, wherein said signal receiver of said microchip additionally comprises a decoder circuit coupled to said memory circuit, said decoder receiving a pulse pause modulated (PPM) RF field from said modulator of said read/write device for digitally evaluating the PPM RF field and the data in order to change the identification data stored in said memory circuit.

4. The combination as recited in claim 3, wherein said memory circuit of said detection microchip additionally comprises a write protected area which can only be written onto once with data.

5. The combination as recited in claim 4, wherein said oscillator of said detection microchip operates at a frequency independent of the frequency of the RF signal from the transmitter of the read/write device.

6. The combination as recited in claim 5, wherein said data receiver of said read/write device comprises a demodulator, and an evaluation circuit coupled to said demodulator for evaluating and indicating the identification data detected from said detection microchip.

7. The combination as recited in claim 6 wherein said detection microchip is freely programmable to operate in said function modes.

8. The combination of a portable, field-programmable detection microchip for storing identification data for identifying persons, animals or objects, and a read/write device for accessing the data stored in the microchip, when brought within RF coupling proximity thereof, the combination defining an identification system comprising:

a read/write device including a transmitter for producing an RF field, a modulator coupled to said transmitter for modulating the RF field, and a data receiver for receiving RF data signals from the detection microchip; and

a detection microchip including

i. a parallel LC resonant circuit tuned to the frequency of said RF field;

ii. a rectifier circuit coupled to said parallel LC resonant circuit;

iii. a charging capacitor coupled to said rectifier circuit for storing electrical energy during the occurrence of the RF field, and powering said microchip during pulse pauses of the RF field;

iv. a signal receiver coupled to said parallel LC resonant circuit for decoding the modulated RF field;

v. a memory circuit for storing the identification data of said microchip;

vi. a code generator coupled to said memory circuit for generating an RF signal modulated with the identification data;

vii. switching means coupled to said parallel LC resonant circuit and said code generator for coupling the identification data from said code generator to said parallel LC resonant circuit, said switching means changing the impedance of said parallel LC resonant circuit during the transmission of the identification data, wherein said signal receiver of said microchip additionally including a decoder circuit; and

viii. a digital multiplexer switch coupled between said decoder circuit and said memory circuit for selectively connecting said decoder circuit to said memory circuit during a transmission of identification data from said read/write device;

said decoder circuit receiving a pulse pause modulated (PPM) RF field from said modulator of said read/write device and digitally evaluating the PPM RF field and the data in order to change the identification data stored in said memory circuit, said digital multiplexer disconnects said decoder circuit from said memory circuit during a transmission from said detection microchip.