FIELD OF INVENTION

The present invention relates to an RFID reader system and a method of reading RFID signals with a wireless communication module. BACKGROUND OF INVENTION

Many universities, corporations, and government facilities are reporting losses of hundreds of thousands of dollars every year. The most disturbing aspect is that only small cases are caused by forcible entries, whereas most of the cases happened due to internal thefts. Because most thefts are internal-related, conventional alarm systems and card access systems are a weak defense. Subsequent costs rise significantly when replacing the equipments, recovering sensitive information, or simply losing time running down misplaced equipments. Therefore, a better solution is required for automated tracking and monitoring assets.

U.S. 2008/0030306 A1 describes an RFID device that is an active transponder which includes a transmitter, receiver and a microprocessor. However, the document does not describe any additional solutions to prevent theft of objects that may be subject to being moved around.

Basically, RFID facilitates remote detection and identification of objects. However, it does not provide information on the condition of the objects it detects. Sensors, on the other hand, provide the information about the condition of the objects as well as the environment. Therefore, a better solution is needed to extend the basic capabilities of standard RFID technology for automated tracking and monitoring. SUMMARY OF INVENTION

Accordingly, the present invention provides an RFID reader system with a wireless communication module is provided, the system includes an RFID tag which further includes a microcontroller coupled to the wireless communication module in the RFID reader system and the RFID tag, a motion sensor coupled to the microcontroller in the RFID tag, wherein the wireless communication module is coupled to an antenna in the RFID system and the RFID tag to transmit and receive data within the RFID reader system and RFID tag.

Furthermore, the present invention also provides a method of reading RFID signals with a wireless communication module, the method includes the steps of configuring the wireless communication module, detecting assertion of an interrupt line, sampling an interrupt signal from the motion sensor, receiving a data packet from an RFID tag, sending the received data packet to a host computer.

The present invention consists of several novel features and a combination of parts hereinafter fully described and illustrated in the accompanying description and drawings, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, wherein: Figure 1 shows an embodiment of an embodiment of an architecture of a RFID reader system without a motion sensor;

Figure 2 shows an embodiment of an embodiment of an architecture of a RFID tag system with a motion sensor;

Figure 3 shows a flowchart of the RFID tag depicting signals from the motion sensor and sending data to the RFID reader system in an embodiment of the present invention;

Figure 4 shows a flowchart of the RFID reader system decoding incoming signals and communicating with host computer to display data in an embodiment of the present invention; and

Figure 5 shows a block diagram of an RFID tag communicating with the RFID reader upon detecting a motion event in an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention relates to an RFID reader system and a method of reading RFID signals with a wireless communication module. Hereinafter, this specification will describe the present invention according to the preferred embodiment of the present invention. However, it is to be understood that limiting the description to the preferred embodiment of the invention is merely to facilitate discussion of the present invention and it is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the scope of the appended claims.

The following detailed description of the preferred embodiment will now be described in accordance with the attached drawings, either individually or in combination.

Figure 1 depicts an embodiment of the present invention of a radio frequency identification (RFID) reader system (100) in a wireless communication module ( 03, 203) coupled to an antenna (108). The system (100) includes an RFID tag (200) which further includes a microcontroller (102, 202) coupled to the wireless communication module (103, 203), a real time clock (105, 205) coupled to the microcontroller (102, 202) and a motion sensor (204) coupled to the microcontroller (102, 202), wherein the wireless communication module (103, 203) transmits and receives data as seen in Figure 2. The wireless communication module (103, 203) is electrically connectable to the antenna ( 08) through a 50 ohm transmission line. A transceiver chip (104) such as MAX3222 is coupled to the microcontroller (102, 202) in the RFID reader system (100) as seen in Figure 1.

A real time clock (105, 205) is further coupled to the microcontroller ( 02, 202) in the RFID reader system (100) as seen in Figure 1. The system (100) is interfaced with a host computer by RS 232 serial communication port (106). The RFID tag (200) is powered by a 3 Volt (V) battery (101 , 201 ) as seen in Figure 1 and 2. The microcontroller (102, 202) further includes an interrupt pin (not shown). The motion sensor (204) is electrically connectable to the interrupt pin of the microcontroller (102, 202).

A method of reading RFID signals in a wireless communication module (103, 203) is described herein as seen in Figure 3. The method includes the steps of configuring the wireless communication module (103, 203), detecting assertion of an interrupt line, sampling an interrupt signal from the motion sensor (204), receiving a data packet from an RFID tag (200), filtering data of a received data packet and sending the received data packet to a host computer.

The RFID reader system (100) is initialized wherein the microcontroller (102, 202) configures the wireless communication module (103, 203) using an interface such as a serial peripheral interface (SPI) (206) as seen in Figure 2. Configuration of registers mounted on the wireless communication module (103, 203) include elements such as data packet length, radio frequency (RF), modulation format, data rate, modem deviation setting and RF output power.

The received data packet from the RFID tag (200) is filtered by checking if address of RFID tag (200) is matched and automated cyclic redundancy codes (CRC) checks. The received data packet is then sent to a host computer using an interface such as RS 232 serial communication port (106).

Upon detection of assertion of the interrupt line, the microcontroller (102, 202) starts sampling an interrupt signal from the motion sensor (204) to validate the motion sensor (204) status. During RFID tag (200) initialization, the microcontroller (102, 202) configures the registers mounted on the wireless communication module (103, 203) using an SPI interface (206). The microcontroller (102, 202) then sends the data packet to wireless communication module (103, 203) through the SPI interface (206) after a confirmation of movement has occurred. The data packet sent to the RFID reader system (100) may include details such as identification number, information related to an object attached to the RFID tag (200) and motion status of said object. The RFID tag (200) communicates with the RFID reader system (100) at a working frequency such as 433.92 Mega Hertz (MHz). The RFID tag (200) can typically have a maximum read range of about 94 meters. It is to be understood that the term "read range" refers to both the range at which the RFID tag (200) can coherently receive interrogation signals transmitted from an RFID reader system (100), as well as the range at which the RFID reader system (100) can coherently receive a returned signal propagated from the RFID tag (200).

The antenna (108) receives a modulated RF signal wherein the wireless communication module (103, 203) demodulates the RF signal. The microcontroller (102, 202) communicates with the wireless communication module (103,203) through the SPI interface (206) to allow for signal transmission and reception.

The RFID tag (200) can be turned off completely to save power as seen in Figure 3 and Figure 4. This is done by enabling sleep mode at the wireless communication module (103, 203) and the microcontroller (102, 202). In order to disable sleep mode for the RFID tag (200), detection of assertion of the interrupt line by a motion event (503) is required (see Figure 5), wherein the interrupt line of the microcontroller (102, 202) is triggered. The motion event (503) asserts the interrupt line of the microcontroller (102, 202) to wake up power and circuitry of the RFID tag (200).

Figure 5 depicts the RFID tag (200) sending out a modulated signal to the RFID reader system (100) upon detection of a motion event (503) as seen in Figure 5. The RFID tag (200) sends details associated with the RFID tag (200) at the working frequency of 433.92 MHz to the RFID reader system (100).

As the RFID reader system (100) has an RFID tag (200) integrated with a motion sensor, the system (100) is capable of detecting movement events as the RFID tag (200) is affixed on an item or a product that needs to be tracked or controlled. However, it is to be understood that components used in this embodiment of the invention are exchangeable for other variations of the same in order to be used in various applications. The present embodiment of the invention is intended for, but not restricted to, use in anti- theft prevention systems, asset management system, animal monitoring system and patient monitoring system in the field of RFID application.