Patent Description:
In an retail environment, lost, stolen, or misplaced merchandises may result in loss revenue for the retail store. As a counter measure, the retail store may place security tags on merchandises to prevent loss. The retail store may use one or more authorized radio frequency (RF) scanners to locate the security tags in order to track the merchandises. If a potential shoplifter attempts to remove a merchandise from the retail store without purchasing the merchandise, the one or more authorized RF scanners may detect the security tag (associated with the stolen merchandise) leaving the retail store. In response, the one or more authorized RF scanners may trigger a notification or alarm.

<CIT> relates generally to security measures, and more particularly, to the use of detected electromagnetic (EM)/radio frequency (RF) emission signature-based personas for security.

In <CIT> discloses a system comprising an RFID module having an energy coupler to receive transmitted energy comprising a first signal at a first frequency and a second signal at a second frequency, and a mixing element to mix the first and second signals, to generate a third signal at a third frequency, and the energy coupler to transmit the third signal to an EAS detection system.

<CIT> describes a method and system for retrieving lost or stolen devices. More particularly, the invention relates to a method and system for identifying lost or stolen portable computers as they pass through an airport checkpoint.

However, the potential shoplifter may utilize an authorized RF device to disrupt the operation of the one or more authorized RF scanners. Therefore, improvements in security system may be desirable.

The above-mentioned object is solved by the subject-matter of independent claims <NUM> and <NUM>.

Preferred embodiments are subject-matter of the dependent claims.

The features believed to be characteristic of aspects of the disclosure are set forth in the appended claims. In the description that follows, like parts are marked throughout the specification and drawings with the same numerals, respectively. The drawing figures are not necessarily drawn to scale and certain figures may be shown in exaggerated or generalized form in the interest of clarity and conciseness. The disclosure itself, however, as well as a preferred mode of use, further objects and advantages thereof, will be best understood by reference to the following detailed description of illustrative aspects of the disclosure when read in conjunction with the accompanying drawings, wherein:.

In some aspects of the present disclosure, a radio frequency identification (RFID) scanner may be configured to detect an unauthorized radio frequency (RF) device. For example, a retail store may use the RFID scanner, with RFID security tags attached to merchandises, to track and/or inventory the merchandises. Specifically, the RFID scanner may identify any merchandise being removed by a shoplifter from the retail store without proper payment. To counter this, the shoplifter may deploy an unauthorized RF device to interfere with the operation of the RFID scanner by "jamming" the RFID scanner.

In one aspect of the present disclosure, the RFID scanner may be configured to distinguish RF signals from an authorized device and the RF signals from an unauthorized device. If the RFID scanner detects unauthorized RF signals, the RFID scanner may activate an alarm to alert the security personnel and/or clerks associated with the retail store. For example, the RFID scanner (or another RFID scanner associated with the retail store) may transmit one or more authorized RF signals intended for the RFID security tags associated with the retail store. The shoplifter may deploy the unauthorized RF device to attempt to jam the RFID scanner by transmitting one or more unauthorized RF signals. The RFID scanner may receive the one or more unauthorized RF signals as one or more incoming RF signals. The RFID scanner may compare the characteristics (e.g., frequency, amplitude, time, duration, waveform shape, phase, etc.) of the one or more authorized RF signals with the characteristics of the one or more incoming RF signals. If the characteristics of the one or more authorized RF signals are different than the characteristics of the one or more incoming RF signals, the RF scanner may determine the presence of the unauthorized RF device, and activate an alarm.

<FIG> illustrates an example of an environment <NUM> (e.g., a retail store) for detecting an unauthorized RF device according to aspects of the present disclosure. The environment <NUM> may include a merchandise <NUM> having a security tag <NUM> attached to the merchandise <NUM>. The security tag <NUM> may be locked (e.g., unable to be removed from the merchandise <NUM> without damaging the merchandise <NUM>) to the merchandise <NUM>. The security tag <NUM> may include a RFID device <NUM> configured to transmit and/or receive RFID signals.

According to the invention, the environment <NUM> includes a RFID scanner <NUM> configured to detect the presence of an unauthorized RF device <NUM>. The RFID scanner <NUM> includes a communication component <NUM> configured to transmit and/or receive RF signals. The RFID scanner <NUM> includes an identification component <NUM> configured to identify one or more characteristics associated with RF signals. The RFID scanner <NUM> includes a determination component <NUM> configured to determine the presence of the unauthorized RF device <NUM> based on the characteristics of authorized RF signals (e.g., configured to be transmitted by the RFID scanner <NUM> or by an optional RF transmitter <NUM>) and the characteristics of unauthorized RF signals. The RFID scanner <NUM> includes an alarm component <NUM> that activates an alarm when detecting the unauthorized RF device <NUM>.

In some aspects, the environment <NUM> may optionally include a control RFID tag <NUM>. The control RFID tag <NUM> may receive RF signals from the RFID scanner <NUM> (or the optional RF transmitter <NUM>), and transmit a control RF signal in response.

During operation, the RFID scanner <NUM> transmits at least one source RF signal <NUM>. The at least one source RF signal <NUM> is intended for the security tag <NUM>. The at least one source RF signal <NUM> is transmitted or be scheduled to be transmitted by the RFID scanner <NUM> and/or the optional RF transmitter <NUM>. In response to receiving the at least one source RF signal <NUM>, the security tag <NUM> transmits at least one response RF signal <NUM> to the RFID scanner <NUM>. The at least one response RF signal <NUM> indicates the location of the security tag <NUM>, merchandise information associated with the merchandise <NUM>, etc..

In some instances, a shoplifter (not shown) may utilize the unauthorized RF device <NUM> to transmit at least one unauthorized RF signal <NUM> to disrupt the operations of the RFID scanner <NUM> and/or the security tag <NUM>. For example, the unauthorized RF device <NUM> may transmit the at least one unauthorized RF signal <NUM> at a power level significantly higher than the power level of the at least one response RF signal <NUM>. As a result, the at least one unauthorized RF signal <NUM> may prevent the RFID scanner <NUM> from properly receiving and/or detecting the at least one response RF signal <NUM>. In another example, the unauthorized RF device <NUM> may transmit the at least one unauthorized RF signal <NUM> to prevent the security tag <NUM> from properly receiving the one or more source RF signals <NUM>. As a result, the security tag <NUM> may not be able to transmit the at least one response RF signal <NUM>.

In some aspects of the present disclosure, the RFID scanner <NUM> may identify, via the identification component <NUM>, the one or more authorized signal characteristic of the at least one authorized RF signal <NUM>. The one or more authorized signal characteristic may include the amplitude, the frequency, the power level (average or instantaneous), duty cycle, transmission time, period, on/off duration, wavelengths, and/or other characteristics of the at least one authorized RF signal <NUM>. The at least one authorized RF signal <NUM> may include portions or all of the at least one source RF signal <NUM>, the at least one response RF signal <NUM>, and/or at least one control RF signal <NUM> (described below).

In some aspects, the RFID scanner <NUM> may utilize hardware and/or software to identify the one or more authorized signal characteristic. For example, the RFID scanner <NUM> may include a frequency counter and/or a resonant circuit (not shown) to determine the frequency of the at least one authorized RF signal <NUM>. In another example, the RFID scanner <NUM> may include a wattmeter to measure the power level of the at least one authorized RF signal <NUM>.

In certain implementations, the RFID scanner <NUM> may receive, via the communication component <NUM>, at least one incoming RF signal <NUM> having one or more incoming signal characteristic. The at least one incoming RF signal <NUM> may be the at least one unauthorized RF signal <NUM> or the at least one authorized RF signal <NUM>. The RFID scanner <NUM> may be unable to distinguish the at least one unauthorized RF signal <NUM> and the at least one authorized RF signal <NUM> until identifying the one or more incoming signal characteristic of the at least one incoming RF signal <NUM>.

In an aspect of the present disclosure, the RFID scanner <NUM> may identify, via the identification component <NUM>, the one or more incoming signal characteristic of the at least one incoming RF signal <NUM>. The one or more incoming signal characteristic may include the amplitude, the frequency, the power level (average or instantaneous), duty cycle, transmission time, period, on/off duration, wavelengths, and/or other characteristics of the at least one incoming RF signal <NUM>.

In some aspect, the RFID scanner <NUM> may determine, via the determination component <NUM>, a presence of the unauthorized RF device <NUM> based on at least one of the one or more authorized signal characteristic of the at least one authorized RF signal <NUM> or the one or more incoming signal characteristic of the at least one incoming RF signal <NUM> (e.g., the at least one unauthorized RF signal <NUM>). The determination may be performed over a specific duration of time.

According to the invention, the RFID scanner <NUM> determines the presence of the unauthorized RF device <NUM> based on the frequency of the at least one authorized RF signal <NUM> being different than the frequency of the at least one unauthorized RF signal <NUM>.

In another example, the RFID scanner <NUM> may determine the presence of the unauthorized RF device <NUM> based on the frequency and/or power level of the at least one authorized RF signal <NUM> being within the regulatory limit while the frequency and/or power level of the at least one unauthorized RF signal <NUM> being beyond the regulatory limit. The at least one unauthorized RF signal <NUM> may be transmitted at a power level above the regulatory threshold and the at least one authorized RF signal <NUM> may be transmitted at a power level below the regulatory threshold. The at least one unauthorized RF signal <NUM> may be transmitted at a frequency beyond the regulatory range and the at least one authorized RF signal <NUM> may be transmitted at a frequency within the regulatory range.

In other examples, the RFID scanner <NUM> may determine the presence of the unauthorized RF device <NUM> based on the transmission time of the at least one authorized RF signal <NUM> being different than the transmission time of the at least one unauthorized RF signal <NUM>. The at least one authorized RF signal <NUM> may be transmitted between the time of t = <NUM> to t = <NUM> milliseconds (ms), and t = <NUM> to t = <NUM>, and may not be transmitted between the time of t = <NUM> to t = <NUM>. At least a portion of the at least one unauthorized RF signal <NUM> may be transmitted (by the unauthorized RF device <NUM>) during the time of t = <NUM> to t = <NUM>. The RFID scanner <NUM> may determine the presence of the unauthorized RF device <NUM> based on at least a portion of the at least one unauthorized RF signal <NUM> being transmitted during the time of t = <NUM> to t = <NUM>.

In one aspect of the present disclosure, the RFID scanner <NUM> and/or the optional RF transmitter <NUM> may transmit the at least one source RF signal <NUM> to the control RFID tag <NUM>. The control RFID tag <NUM> may respond with the at least one control RF signal <NUM> to the RFID scanner <NUM>. If the unauthorized RF device <NUM> transmits the at least one unauthorized RF signal <NUM>, the control RFID tag <NUM> may be unable to properly receive the at least one source RF signal <NUM>, and/or transmit the at least one control RF signal <NUM>. The RFID scanner <NUM> may determine the presence of the unauthorized RF device <NUM> based on the RFID scanner <NUM> being unable to detect the at least one control RF signal <NUM> after transmitting the at least one source RF signal <NUM>.

In some aspects of the present disclosure, the RFID scanner <NUM> may periodically receive background signals, including one or more of the at least one authorized RF signal <NUM>, and/or signals from other transmitters in the environment <NUM> (e.g., cellular phones belonging to customers in the retail store). The RFID scanner <NUM> may determine a background power level associated with the background signals. If the unauthorized RF device <NUM> transmits the at least one unauthorized RF signal <NUM>, the RFID scanner <NUM> may receive the at least one unauthorized RF signal <NUM> as the at least one incoming RF signal <NUM>. The RFID scanner <NUM> may determine that the power level associated with the at least one incoming RF signal <NUM> exceeds the background power level. In response, the RFID scanner <NUM> may determine the presence of the unauthorized RF device <NUM>.

In some aspect, the RFID scanner <NUM> may activate an alarm <NUM>, via the alarm component <NUM>, in response to determining the presence of the unauthorized RF device <NUM>. In some examples, the RFID scanner <NUM> may send an alarm signal <NUM> to an optional alarm system (not shown) in the RFID scanner <NUM> to activate the alarm system (e.g., audio siren and/or visual light). In another example, the RFID scanner <NUM> may transmit an indication signal (e.g., the alarm signal <NUM>) to an external alarm system (e.g., the alarm <NUM>) to activate the external alarm system. The alarm system (optional and/or external) may alert personnel associated with the environment <NUM> (e.g., retail store clerk, security, etc.) regarding the presence of the unauthorized RF device <NUM>.

Referring to <FIG> and <FIG>, an example of the RFID scanner <NUM> may be configured to transmit the at least one source RF signal <NUM> and/or receive the at least one incoming RF signal <NUM>. The RFID scanner <NUM> may include a processor <NUM> that executes instructions stored in a memory <NUM> for detecting the unauthorized RF device <NUM> described herein.

The term "processor," as used herein, can refer to a device that processes signals and performs general computing and arithmetic functions. Signals processed by the processor can include digital signals, data signals, computer instructions, processor instructions, messages, a bit, a bit stream, or other computing that can be received, transmitted and/or detected. A processor, for example, can include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described herein. The term "memory," as used herein, can include volatile memory and/or nonvolatile memory. Non-volatile memory can include, for example, ROM (read only memory), PROM (programmable read only memory), EPROM (erasable PROM) and EEPROM (electrically erasable PROM). Volatile memory can include, for example, RAM (random access memory), synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), and direct RAM bus RAM (DRRAM).

The term "memory," as used herein, can include volatile memory and/or nonvolatile memory. Non-volatile memory can include, for example, ROM (read only memory), PROM (programmable read only memory), EPROM (erasable PROM) and EEPROM (electrically erasable PROM). Volatile memory can include, for example, RAM (random access memory), synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), and direct RAM bus RAM (DRRAM).

In some implementations, the RFID scanner <NUM> may include the memory <NUM>. The RFID scanner <NUM> may include a RFID driver <NUM> configured to transmit and/or receive RF signals via a scanner coil <NUM>. The RFID driver <NUM> may energize the scanner coil <NUM> to transmit the RF signals. The scanner coil <NUM> may include one or more inductors that transmit or receive electromagnetic signals. Additionally, in some non-limiting examples, the security tag <NUM> may include the RFID device <NUM> that transmits and/or receives RF signals via a tag coil <NUM>.

During operation, in some implementations, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> of the RFID scanner <NUM> may identify the one or more authorized signal characteristic associated with one or more authorized RF signal. For example, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> of the RFID scanner <NUM> may identify the one or more authorized signal characteristic of the at least one authorized RF signal <NUM>. The at least one authorized RF signal <NUM> may be transmitted by the RFID scanner <NUM> the optional RF transmitter <NUM>, the security tag <NUM>, the control RFID tag <NUM>, and/or other authorized RF devices in the environment <NUM>.

In an implementation, the processor <NUM>, the memory <NUM>, and/or the communication component <NUM> of the RFID scanner <NUM> may receive the at least one incoming RF signal <NUM>. For example, the processor <NUM>, the memory <NUM>, and/or the communication component <NUM> of the RFID scanner <NUM> may receive the at least one incoming RF signal <NUM>. The at least one incoming RF signal <NUM> may be a portion or all of the at least one unauthorized RF signal <NUM>.

In certain aspects, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> of the RFID scanner <NUM> may identify the one or more incoming signal characteristic of the at least one incoming RF signal <NUM>. For example, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> of the RFID scanner <NUM> may identify the amplitude, the frequency, the power level (average or instantaneous), duty cycle, transmission time, period, on/off duration, wavelengths, and/or other characteristics of the at least one incoming RF signal <NUM>.

In some aspects of the present disclosure, the memory <NUM>, and/or the determination component <NUM> of the RFID scanner <NUM> may determine a presence of the unauthorized RF device <NUM> based on at least one of the one or more authorized signal characteristic and/or the one or more incoming signal characteristic as described above.

In one aspect of the present disclosure, the processor <NUM>, the memory <NUM>, and/or the alarm component <NUM> may activate an alarm system in response to determining the presence of the unauthorized RF device <NUM> as described above.

Turning to <FIG>, an example of a method <NUM> for determining the presence of an unauthorized RF device may be performed by one or more of the communication component <NUM>, the identification component <NUM>, the determination component <NUM>, the alarm component <NUM>, the processor <NUM>, the memory <NUM>, the RFID driver <NUM>, and/or the scanner coil <NUM> of the RFID scanner <NUM>.

At block <NUM>, the method <NUM> may identify one or more authorized signal characteristic associated with one or more authorized RF signal. For example, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> may identify one or more authorized signal characteristic associated with the one or more authorized RF signal <NUM> as described above. The processor <NUM>, the memory <NUM>, and/or the identification component <NUM> may be configured to and/or define means for identifying one or more authorized signal characteristic associated with one or more authorized RF signal.

At block <NUM>, the method <NUM> may receive at least one incoming RF signal having one or more incoming signal characteristic. For example, the processor <NUM>, the memory <NUM>, the communication component <NUM>, the RFID driver <NUM>, and/or the scanner coil <NUM> may receive the at least one incoming RF signal <NUM> having one or more incoming signal characteristic as described above. The processor <NUM>, the memory <NUM>, the communication component <NUM>, the RFID driver <NUM>, and/or the scanner coil <NUM> may be configured to and/or define means for receiving at least one incoming RF signal having one or more incoming signal characteristic.

At block <NUM>, the method <NUM> may identify the one or more incoming signal characteristic. For example, the processor <NUM>, the memory <NUM>, and/or the identification component <NUM> may identify the one or more incoming signal characteristic as described above. The processor <NUM>, the memory <NUM>, and/or the identification component <NUM> may be configured to and/or define means for identifying the one or more incoming signal characteristic.

At block <NUM>, the method <NUM> may determine a presence of the unauthorized RF device based on at least one of the one or more authorized signal characteristic or the one or more incoming signal characteristic. For example, the processor <NUM>, the memory <NUM>, and/or the determination component <NUM> may determine a presence of the unauthorized RF device <NUM> based on at least one of the one or more authorized signal characteristic or the one or more incoming signal characteristic as described above. The processor <NUM>, the memory <NUM>, and/or the determination component <NUM> may be configured to and/or define means for determining a presence of the unauthorized RF device based on at least one of the one or more authorized signal characteristic or the one or more incoming signal characteristic.

At block <NUM>, the method <NUM> may activate an alarm in response to determining the presence of the unauthorized RF device. For example, the processor <NUM>, the memory <NUM>, and/or the alarm component <NUM> may activate the alarm <NUM> in response to determining the presence of the unauthorized RF device <NUM>. The processor <NUM>, the memory <NUM>, and/or the alarm component <NUM> may be configured to and/or define means for transmitting a wireless signal to the wireless device to enable the RFID device to receive a RFID signal used to unlock the security tag from the merchandise.

Aspects of the present disclosures may be implemented using hardware, software, or a combination thereof and may be implemented in one or more computer systems or other processing systems. In an aspect of the present disclosures, features are directed toward one or more computer systems capable of carrying out the functionality described herein. An example of such the computer system <NUM> is shown in <FIG>. In some examples, the RFID scanner <NUM> may be implemented as the computer system <NUM> shown in <FIG>. The RFID scanner <NUM> may include some or all of the components of the computer system <NUM>.

The computer system <NUM> includes one or more processors, such as processor <NUM>. The processor <NUM> is connected with a communication infrastructure <NUM> (e.g., a communications bus, cross-over bar, or network). Various software aspects are described in terms of this example computer system. After reading this description, it will become apparent to a person skilled in the relevant art(s) how to implement aspects of the disclosures using other computer systems and/or architectures.

The computer system <NUM> may include a display interface <NUM> that forwards graphics, text, and other data from the communication infrastructure <NUM> (or from a frame buffer not shown) for display on a display unit <NUM>. Computer system <NUM> also includes a main memory <NUM>, preferably random access memory (RAM), and may also include a secondary memory <NUM>. The secondary memory <NUM> may include, for example, a hard disk drive <NUM>, and/or a removable storage drive <NUM>, representing a floppy disk drive, a magnetic tape drive, an optical disk drive, a universal serial bus (USB) flash drive, etc. The removable storage drive <NUM> reads from and/or writes to a removable storage unit <NUM> in a well-known manner. Removable storage unit <NUM> represents a floppy disk, magnetic tape, optical disk, USB flash drive etc., which is read by and written to removable storage drive <NUM>. As will be appreciated, the removable storage unit <NUM> includes a computer usable storage medium having stored therein computer software and/or data. In some examples, one or more of the main memory <NUM>, the secondary memory <NUM>, the removable storage unit <NUM>, and/or the removable storage unit <NUM> may be a non-transitory memory.

Alternative aspects of the present disclosures may include secondary memory <NUM> and may include other similar devices for allowing computer programs or other instructions to be loaded into computer system <NUM>. Such devices may include, for example, a removable storage unit <NUM> and an interface <NUM>. Examples of such may include a program cartridge and cartridge interface (such as that found in video game devices), a removable memory chip (such as an erasable programmable read only memory (EPROM), or programmable read only memory (PROM)) and associated socket, and the removable storage unit <NUM> and the interface <NUM>, which allow software and data to be transferred from the removable storage unit <NUM> to computer system <NUM>.

Computer system <NUM> may also include a communications circuit <NUM>. The communications circuit <NUM> may allow software and data to be transferred between computer system <NUM> and external devices. Examples of the communications circuit <NUM> may include a modem, a network interface (such as an Ethernet card), a communications port, a Personal Computer Memory Card International Association (PCMCIA) slot and card, etc. Software and data transferred via the communications circuit <NUM> are in the form of signals <NUM>, which may be electronic, electromagnetic, optical or other signals capable of being received by the communications circuit <NUM>. These signals <NUM> are provided to the communications circuit <NUM> via a communications path (e.g., channel) <NUM>. This path <NUM> carries signals <NUM> and may be implemented using wire or cable, fiber optics, a telephone line, a cellular link, an RF link and/or other communications channels. In this document, the terms "computer program medium" and "computer usable medium" are used to refer generally to media such as the removable storage unit <NUM>, a hard disk installed in hard disk drive <NUM>, and signals <NUM>. These computer program products provide software to the computer system <NUM>. Aspects of the present disclosures are directed to such computer program products.

Computer programs (also referred to as computer control logic) are stored in main memory <NUM> and/or secondary memory <NUM>. Computer programs may also be received via communications circuit <NUM>. Such computer programs, when executed, enable the computer system <NUM> to perform the features in accordance with aspects of the present disclosures, as discussed herein. In particular, the computer programs, when executed, enable the processor <NUM> to perform the features in accordance with aspects of the present disclosures. Accordingly, such computer programs represent controllers of the computer system <NUM>.

Claim 1:
A method of detecting an unauthorized radio frequency (RF) device (<NUM>) by a RF scanner (<NUM>), comprising:
- identifying, at the RF scanner (<NUM>), one or more authorized signal characteristic associated with at least one authorized RF signal (<NUM>);
- transmitting, by the RF scanner (<NUM>), at least one source RF signal (<NUM>) to read a security tag (<NUM>) configured to respond with at least one control RF signal;
- receiving, at the RF scanner (<NUM>), in response to transmitting the at least one source RF signal (<NUM>), at least one incoming RF signal (<NUM>) having one or more incoming signal characteristic, wherein the at least one incoming RF signal (<NUM>) is different than the at least one authorized RF signal (<NUM>);
- identifying, at the RF scanner (<NUM>), the one or more incoming signal characteristic;
- determining, at the RF scanner (<NUM>), a presence of the unauthorized RF device (<NUM>) based on at least one of the one or more authorized signal characteristic or the one or more incoming signal characteristic; and
- activating an alarm in response to determining the presence of the unauthorized RF device (<NUM>).