Antenna for a read/write unit for radio frequency identification (RFID) arrangements, and read/write unit for operation with an external antenna

• US 9,904,823 B2
• Filed: 09/20/2013
• Issued: 02/27/2018
• Est. Priority Date: 09/21/2012
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Horst, Dieter, Mayer, Lukas Walter, Resel, Leopold, Schiefer, Martin
• Primary Examiner(s): King, Curtis
• Application Number:
  US14/032,514
• Publication Number:
  US 20140085057A1
• Time in Patent Office: 1,621 Days
• Field of Search: None
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment

Abstract

An antenna, a read/write unit, an radio frequency identification (RFID) arrangement and a method, wherein the antenna is configured to connect to an external antenna connection of the read/write unit via an antenna line, wherein the antenna includes a data memory having type information and/or having property information, the content of the data memory being readable by the read/write unit, and includes a measuring device for determining a value of the field strength or power of a radio frequency signal fed into the antenna by the read/write unit, and includes a device for informing the read/write unit about the value being reached or exceeded.

Claims

1. An antenna for a read/write unit for radio frequency identification arrangements, the antenna being configured to connect to an external antenna connection of the read/write unit via an antenna line, the antenna comprising:

a data memory having at least one of type information and property information, a content of the data memory being readable by the read/write unit;

a directional coupler integrated into the antenna and operatively coupled to the data memory;

a measuring device integrated into the antenna, said measuring unit determining at least one value of a field strength or power of a radio-frequency signal that is fed into the antenna by the read/write unit, said radio-frequency signal being decoupled by the directional coupler; and

means for informing the read/write unit about the at least one value being reached or exceeded.

2. The antenna as claimed in claim 1, wherein the antenna is configured to transmit the content of the data memory and to inform the read/write unit about the at least one value being reached or exceeded via modulated backscattering based on an RFID protocol.

3. The antenna as claimed in claim 1, further comprising:

a power sensor comprising a measuring device, the power sensor being coupled to a radio-frequency line or to a radiation element of the antenna, and the power sensor being configured and connected up such that the data memory is activated when a minimum value of the field strength or the power is reached or exceeded;

wherein a minimum power is utilizable as the at least one value.

4. The antenna as claimed in claim 3, wherein the data memory comprises an RFID transponder

wherein the RFID transponder is coupled to one of the radio-frequency line and the radiation element of the antenna;

and

wherein the RFID transponder is activatable by reaching or exceeding a minimum field strength or power, activation of the RFID transponder being reportable to the read/write unit as the at least one value being reached or exceeded.

5. The antenna as claimed in claim 4, wherein the RFID transponder is utilizable with a defined activation threshold as the measuring device.

6. The antenna as claimed in claim 1, wherein a level of the at least one value is at least one of stored in the data memory and ascertainable from a piece of type information that is stored in the data memory, the at least one value being transmittable to the read/write unit.

7. The antenna as claimed in claim 6, wherein the level of the at least one value comprises a threshold value or a response threshold.

8. The antenna as claimed in claim 1, wherein the antenna is configured to transmit the content of the data memory and to inform the read/write unit about the at least one value being reached or exceeded via a modulated low-frequency signal on the antenna line.

9. The antenna as claimed in claim 1, wherein the antenna is configured to transmit the content of the data memory and to inform the read/write unit about the at least one value being reached or exceeded via clocked shorting of the antenna line, the clocked shorting allowing bit-by-bit transmission of the information that is to be transmitted.

10. The antenna as claimed in claim 1, wherein at least one of the data memory and the measuring device is activatable by one of a signal received via the antenna line and a DC voltage present on the antenna line.

11. The antenna as claimed in claim 1, further comprising:

a control device configured to transmit the content of the data memory and at least one absolute value for the field strength or power of the radio-frequency signal to the read/write unit, the at least one absolute value being respectively measured by the measuring device.

12. The antenna as claimed in claim 11, wherein the control device comprises a microcontroller.

13. The antenna as claimed in patent claim 11, wherein the control device comprises the data memory.

14. A read/write unit for radio frequency identification arrangements, the read/write unit being configured to at least one of adjust a transmission power and determine a maximum transmission power based on a type or properties of an antenna including a measuring device integrated into the antenna and based on a damping of an antenna line operatively coupled to a directional coupler integrated into the antenna;

wherein the read/write unit is configured to read a piece of type or property information from the antenna and to automatically take account of the damping by receiving a piece of information about at least one value for a field strength or power of a radio-frequency signal received in the antenna including the measuring device and the directional coupler from the read/write unit being reached or exceeded and to relate the at least one value to a relative or absolute value for the radio-frequency signal output by the read/write unit, said radio-frequency signal being decoupled by the directional coupler; and

wherein the read/write unit is configured to ascertain one of a maximum transmission power and a transmission power that is to be used from the type or property information and from a relationship between the power of the output radio-frequency signal and the information about the at least one value.

15. A system comprising:

a read/write unit for radio frequency identification arrangements, the read/write unit being configured to at least one of adjust a transmission power and determine a maximum transmission power based on a type or properties of an antenna and based on a damping of an antenna line; and

an external antenna connected via a connecting line, the external antenna being configured to connect to an external antenna connection of the read/write unit via the antenna line, the external antenna comprising;

a data memory having at least one of type information and property information, a content of the data memory being readable by the read/write unit;

a directional coupler integrated into the antenna and operatively coupled to the data memory;

a measuring device integrated into the external antenna, said measuring device determining at least one value of a field strength or power of a radio-frequency signal that is fed into the antenna by the read/write unit, said radio-frequency signal being decoupled by the directional coupler; and

means for informing the read/write unit about the at least one value being reached or exceeded;

wherein the system is configured to automatically match the read/write unit to the external antenna and the antenna line;

wherein the read/write unit is configured to read a piece of type or property information from the external antenna and to automatically take account of the damping by receiving a piece of information about at least one value for a field strength or power of a radio-frequency signal received in the external antenna from the read/write unit being reached or exceeded and to relate the at least one value to a relative or absolute value for the radio-frequency signal output by the read/write unit; and

wherein the read/write unit is configured to ascertain one of a maximum transmission power and a transmission power that is to be used from the type or property information and from a relationship between the power of the output radio-frequency signal and the information about the at least one value.

16. A method for matching a read/write unit for radio frequency identification arrangements to an external antenna that is connected via a connecting line, the method comprising:

reading, by the read/write unit, at least one of a piece of type information and property information from the external antenna;

outputting, by the read/write unit, at least one radio-frequency signal and feeding the at least one radio-frequency signal into the external antenna, said radio-frequency signal being decoupled by a directional coupler;

transmitting by the external antenna a piece of information about at least one value of the radio-frequency signal captured in the external antenna being reached or exceeded to the read/write unit, a measuring device and the directional coupler being integrated into the external antenna; and

utilizing, by the read/write unit, at least one of the piece of type information and the property information from the external antenna and utilizing a relationship between a relative or absolute output power and the at least one value to perform an adjustment to achieve maximum transmission power.

17. An antenna for a read/write unit for radio frequency identification arrangements, the antenna being configured to connect to an external antenna connection of the read/write unit via an antenna line, the antenna comprising:

a data memory having at least one of type information and property information, a content of the data memory being readable by the read/write unit;

a directional coupler integrated into the antenna and operatively coupled to the data memory;

a measuring device integrated into the antenna, said measuring unit determining at least one value of a field strength or power of a radio-frequency signal that is fed into the antenna by the read/write unit, said radio-frequency signal being decoupled by the directional coupler; and

means for informing the read/write unit about the at least one value being reached or exceeded;

wherein the antenna is configured to transmit the content of the data memory via clocked shorting of the antenna line to allow bit-by-bit transmission of the information that is to be transmitted.