Patent Publication Number: US-2011068903-A1

Title: Mobile communication terminal including rfid reader and transception method thereof

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 11/532,284, filed on Sep. 15, 2006 and noticed to issue by the USPTO on Dec. 14, 2010 as U.S. Pat. No. 7,853,289, and claims priority from and the benefit of Korean Patent Application No. 10-2005-0088083, filed on Sep. 22, 2005, all of which are hereby incorporated by reference for all purposes as if fully set forth herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a mobile communication terminal including a Radio Frequency Identification (RFID) reader and a transception method thereof. More specifically, the present invention relates to a mobile communication terminal including an RFID is reader having a shared antenna for RFID transception and wireless telecommunications transception. 
     2. Discussion of the Background 
     Today&#39;s mobile communication terminal may perform many various functions, such as wirelessly connecting to the internet, video conferencing, text messaging, and video messaging, in addition to voice communication as information communication technologies continue to develop. 
     As the digital age continues to mature, mobile communication terminals have developed into high-speed digital information terminals capable of transmitting a high quantity of data at a very high speed. Thus, efforts have been made to form one network over which the terminals may operate. For this network, technologies including wireless local area networks (LANs), Bluetooth, and RFID have been used. 
     RFID is one technology in the field of automatic recognition technology, which includes bar codes, magnetic sensors and IC-cards or “Smart” cards. RFID includes technology whereby data or information stored in a microchip on an RIFID tag may be read or recognized wirelessly by an RFID reader using RF waves, which may be for example high frequency (HF), very high frequency (VHF), or ultra high frequency (UHF) waves. The RFID tag may be passive, whereby the RFID tag has no independent source of power. These passive RFID tags may draw sufficient power to transmit a signal representing the data stored in the microchip from the RF waves transmitted from the RFID reader. Alternatively, the RFID tag may be active, whereby the RFID tag may include its own source of power for transmitting data to the RFID reader. The RFID tag may be a transponder. Accordingly, upon receiving an RFID signal from the RFID reader, the RFID tag may automatically transmit a signal representing data or information, or a signal including data or information stored in the microchip. 
     Currently, RFID technology has been widely used in industries instead of the bar code. One advantage of the RFID is that the RFID tag may transmit data stored in the microchip without needing to contact a reader directly or without needing to be visibly scanned by the reader. Rather, the RFID tag may be in the proximity of the reader to transmit the data. The proximity of the RFID tag and RFID reader for successful transmission of data may depend on an operating frequency of the RFID tag and RFID reader. For example, an RFID tag and RFID reader operating in a HF range may be able to transmit data within a range of approximately one meter of the RFID reader. 
     RFID technology has become popular over internet and LAN technology as a type of automatic recognition technology because the RFID reader and RFID tag may operate outside of a range of a wireless connection to the internet or to an LAN. 
     As a result of the advantages of the RFID technology, a mobile communication terminal with a built-in RFID reader as described above has been developed. 
       FIG. 1  shows a block diagram illustrating a conventional mobile communication terminal with a built-in RFID reader. While the conventional mobile communication terminal shown in  FIG. 1  will be described as a Global System for Mobile Communication (GSM)-based mobile communication terminal, mobile communication terminals operating according to other wireless protocols, such as Code Divisional Multiple Access (CDMA) or Wideband CDMA (WCDMA), may be similarly arranged. 
     The conventional mobile communication terminal with a built-in RFID reader may include a GSM base band unit  10 , a GSM RF unit  20  controlled by the GSM base band unit  10  is for performing transception of voice communication, and an RFID unit  30  with a built-in RFID reader for transception of RFID-based signals. Transception shall mean both transmission and reception of signals, such as voice signals, information signals, data signals, or RFID signals, and shall not be spatially limited to only transmission or only reception at an instant of time. 
     The GSM RF unit  20  may include an RF transception unit  21 , a clock generating unit  22 , a filter  23 , a high output amplifier unit  24  with a first power amplifier PA 1  and a second power amplifier PA 2 , an antenna switch module  25  and an antenna  26 . The RFID unit  30  may include an RFID reader control unit  40 , an RFID RF unit  50  and antenna  80 . 
     More specifically, the RFID RF unit  50  may include an RFID transception unit  60 , a switch SW 1  and an RFID reception unit  70 . The switch SW 1  may have two positions and may allow the RFID transception unit  60  to transmit a transmission signal from the antenna  80  while the switch SW 1  is in a first position, and may allow the RFID reception unit  70  to receive a reception signal at the antenna  80  when the switch SW 1  is in a second position. The RFID transception unit  60  may include a modulator  61 , a first amplifier AMP 1 , a second amplifier AMP 2 , a third power amplifier PA 3 , a first filter F 1 , a second filter F 2 , a power division unit  62  and an attenuation unit  63 . The RFID reception unit  70  may include a demodulator  71 , a power division unit  72 , a low noise amplifier LNA 1  and a third filter F 3 . 
     The demodulator  71  may include mixer M 1  and mixer M 2 , amplifier AMP 3  and amplifier AMP 4 , filter F 4  and filter F 5 , and amplifier AMP 5  and amplifier AMP 6 . The mixer M 1  and mixer M 2  may each demodulate a power-divided signal of the power division unit  72  and downconvert the frequency of the power-divided signals. The amplifier AMP 3  and amplifier AMP 4  may amplify output signals of the mixer M 1  and the mixer M 2 , respectively. The filter F 4  and filter F 5  may filter output signals of the amplifier AMP 3  and amplifier AMP 4 , respectively. The amplifier AMP 5  and amplifier AMP 6  may amplify output signals of the filter F 4  and filter F 5 , respectively. The output signals of amplifier AMP 5  and amplifier AMP 6  may be output to RFID reader control unit  40 . 
     The modulator  61  may modulate a transmission signal and regulate its frequency upward, and the demodulator  71  may demodulate a reception signal and regulate its frequency downward. The transmission signal and the reception signal may each correspond to an operating frequency of the RFID, which may be 13.56 MHz. 
     The above-described mobile communication terminal with a built-in RFID reader may control the GSM RF unit  20  and the RFID RF unit  50  separately through the GSM base band unit  10 . As a result, a circuit may be complicated, thus increasing the manufacturing cost, and the circuit may occupy a large area in the mobile communication terminal. Thus, the size requirements of the circuit may prevent the terminal from being sized smaller according to the prevailing trend in terminal sizes. 
     Moreover, the RFID unit  30  may not operate properly and may not be recognized when separated from the reader by a distance greater than one meter because the RFID may be configured to operate at an HF frequency, such as 13.56 MHz, which is lower than an operating frequency of the GSM RF Unit  20  since the GSM RF Unit  20  may operate in the UHF band. 
     SUMMARY OF THE INVENTION 
     Embodiments of this invention provide a mobile communication terminal including an RFID reader having a shared antenna for RFID transception. 
     Embodiments of this invention also provide a transception method for transceiving signals related to the mobile communication terminal and for transceiving signals related to the RFID reader using the shared antenna. 
     Additional features of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. 
     An embodiment of the present invention discloses a mobile communication terminal including a base band unit for controlling the mobile communication terminal, a radio frequency (“RF”) unit coupled with the base band unit and including an antenna, the RF unit for transceiving a first signal in response to a control signal received from the base band unit, the first signal representing voice or data communications, and an RFID unit coupled with the RF unit, the RFID unit for transceiving a second signal with a RFID transponder in response to a control received from the base band unit. Further, the first signal and the second signal are both transceived through the antenna. 
     An embodiment of the present invention discloses a method for transceiving an RFID signal of a mobile communication terminal including an RFID reader. The method includes encoding and signal-processing an RFID transmission signal in a low frequency band, upconverting a frequency of the RFID transmission signal, receiving an RFID reception signal in a high frequency band, downconverting a frequency of the RFID reception signal, and decoding and signal-processing the RFID reception signal in a low frequency band. 
     An embodiment of the present invention discloses a mobile communication terminal including a base band unit for controlling the mobile communication terminal, a radio frequency (“RF”) unit coupled with the base band unit, the RF unit for transceiving a first signal, the RF unit having an antenna, a path selection unit, and an RFID transmission selection unit. The mobile communication terminal also includes an RFID unit comprising an RFID transmission unit and an RFID receiving unit, the RFID unit for transceiving a second signal. Further, an output terminal of the RFID transmission unit is coupled with an input terminal of the RFID transmission selection unit, an input terminal of the RFID receiving unit is coupled with an output terminal of the path selection unit, and the mobile communication terminal transceives the first signal and the second signal using a cellular communication protocol through the antenna. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention. 
         FIG. 1  shows a block diagram illustrating a conventional mobile communication terminal with a built-in RFID reader. 
         FIG. 2  shows a block diagram illustrating a mobile communication terminal with a built-in RFID reader according to an exemplary embodiment of the present invention. 
         FIG. 3  shows a flow chart illustrating a method for processing a transception signal of a UHF band of the mobile communication terminal with the built-in RFID reader of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
     The invention is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure is thorough, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like reference numerals in the drawings denote like elements. 
     It will be understood that when an element or layer is referred to as being “on” or “connected to” another element or layer, it can be directly on or directly connected to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on” or “directly connected to” another element or layer, there are no intervening elements or layers present. 
       FIG. 2  shows a block diagram illustrating a mobile communication terminal with a built-in RFID reader according to an exemplary embodiment of the present invention. While the conventional mobile communication terminal shown in  FIG. 2  will be described as a GSM-based mobile communication terminal, mobile communication terminals operating with other wireless protocols, such CDMA or W-CDMA, may be similarly arranged, and the invention is not limited thereto. 
     In this exemplary embodiment, the mobile communication terminal may include a GSM base band unit  100 , a GSM RF unit  200  and a RFID unit  300 . 
     The GSM base band unit  100  may transceive a transception signal with the GSM RF block  200  for voice and data communication, and may transceive a transception signal with the RFID unit  300  for RFID communication. The GSM base band unit  100  may also output a control signal to the GSM RF block  200  for controlling the GSM RF block  200 , and specifically an RFID transmission selection unit  240  and a path selection unit  270 . The GSM base band unit  100  may also output a control signal to the RFID RF unit  500  for controlling the RFID RF unit  500 . The GSM base band unit  100  may output control signals through a General Purpose Input/Output (GPIO) device (not shown). 
     The GSM base band unit  100  may control the GSM RF block  200  and the RFID RF unit  500  to display or transmit data in the mobile communication terminal using information related to a reception signal in voice and data communication through the GSM RF unit  200  and in RFID communication through the RFID unit  300 . 
     The GSM RF unit  200  may include an RF transception unit  210 , a clock generating unit  220 , a filter  230 , the RFID transmission selection unit  240 , a high output amplifier unit  250  including two amplifiers PA 4  and PA 5 , the path selection unit  270 , an antenna switch module  260  and an antenna  280 . 
     The RF transception unit  210 , coupled with the GSM base band unit  100 , may apply a reception signal received from the antenna  280  into the GSM base band unit  100 . 
     The clock generating unit  220  may generate a clock signal CLK in response to a command from the GSM base band unit  100  and may apply the clock signal CLK to the RF transception unit  210 . 
     The filter  230  may be a surface acoustic wave (SAW) filter and may filter a signal applied from the antenna switch module  260  to remove noise, and may apply the signal to the RF transception unit  210 . 
     The RFID transmission selection unit  240  may apply a transmission signal outputted from the RFID transmission unit  600  of the RFID unit  500  to an input terminal of the high output amplifier unit  250  when the RFID unit  500  is in a transmission mode. 
     The RFID transmission selection unit  240  may selectively output the transmission signal of the RFID unit  500  or an output signal of the RF transception unit  210 . The RFID transmission selection unit  240  may apply only a transmission signal of the RFID unit  500  to the antenna switch module  260  when the RFID unit  500  is in the transmission mode. When the RFID unit  500  is in a transmission mode, the RF transception unit  210  may be turned off. Alternatively, the RFID transmission selection unit  240  may include a switch to prevent transmission of an output signal of the RF transception unit  210  to the antenna switch module  260  when the RFID unit  500  is in the transmission mode. 
     The high output amplifier unit  250  including power amplifiers PA 4  and PA 5  may amplify an output signal of the RF transception unit  210  or an output signal of the RFID transmission selection unit  240 . The high output amplifier unit  250  then outputs the amplified signals to the antenna switch module  260 . 
     The power amplifier PA 5  may be configured to operate at a first band, such as a band ranging from 824 to 915 MHz, and may be used for amplifying signals in the first band, such as GSM or RFID signals. The power amplifier PA 4  may be configured to operate at a second band, such as a band ranging from 1710 to 1910 MHz, and may be used for amplifying signals in the second band, such as a Digital Cellular System (DCS) or a Personal Communication Service (PCS). 
     The antenna switch module  260 , which may include a transmission module for operating in a transmission mode and a reception module for operating in a reception mode, may transmit a transmission signal outputted from the high output amplifier unit  250  to the antenna  280  in the transmission mode. The antenna switch module  260  may also transmit a reception signal received from an external mobile communication terminal (not shown) through the antenna  280  to the filter  230  in a reception mode. The antenna switch module  260  may be configured to transceive signals in a band of about 824 MHz to about 960 MHz and about 1710 MHz to about 1990 MHz. 
     The path selection unit  270 , which may include a switch SW 2 , may be coupled between the antenna switch module  260  and the filter  230 . The path selection unit  270  may control transmission of a reception signal received from the antenna switch module  260  through the antenna  280  into the filter  230  or into the RFID reception unit  700 . 
     More specifically, a first output terminal of the switch SW 2  may be coupled with a terminal of the filter  230  in the GSM RF Unit  200 . A second output terminal of the switch SW 2  may be coupled with an input terminal of the RFID reception unit  700  of the RFID unit  300 . Depending on the positioning of the switch SW 2 , a reception signal from the antenna switch module  260  may be transmitted to the filter  230  when the mobile communication terminal is in a GSM reception mode. Alternatively, a reception signal from the antenna switch module  260  may be transmitted to the RFID reception unit  700  of the RFID unit  500  when the mobile communication terminal is in an RFID reception mode. 
     Operation of the RFID transmission selection unit  240 , the antenna switch module  260  and the path selection unit  270  may be controlled by a control signal outputted from the GSM base band unit  100 . 
     The RFID unit  300  may include an RFID reader control unit  400  and an RFID RF block  500 . 
     The RFID reader control unit  400  may encode a transmission signal received from the GSM base band unit  100 , and may convert a digital signal received from the GSM base band unit  100  into an analog signal and apply the analog signal to the RFID transmission unit  600 . Then, the RFID reader control unit  400  may receive a reception signal from the RFID reception is unit  700 , may decode the reception signal, and may converts an analog signal from the RFID reception unit  700  into a digital signal and apply the digital signal to the GSM base band unit  100 . 
     The RFID RF block  500  may include an RFID transmission unit  600  and an RFID reception unit  700 . 
     The RFID transmission unit  600  may include a modulator  610 , amplifiers AMP 7  and AMP 8 , a filter F 6 , a power division unit  620  and an attenuation unit  630 . 
     The modulator  610  may modulate the analog transmission signal, which may be signal-processed by and received from the RFID reader control unit  400 , and may upconvert the frequency of the signal to a higher frequency band, such as a UHF band. Upconverting a signal shall include shifting a frequency of a signal from a lower frequency band to a higher frequency band without significantly altering the content of the message, data, or information stored in the signal. The frequency band of the transmission signal may be set within a range of about 860 MHz to about 915 MHz, about 824 MHz to about 960 MHz, and about 1710 MHz to about 1990 MHz. 
     The amplifier AMP 7  may amplify the transmission signal outputted from the modulator  610  to transmit the signal into the filter F 6 . The filter F 6  may filter the transmission signal. Then, the amplifier AMP 8  may amplify the transmission signal, and the power division unit  620  may power-divide the transmission signal. The attenuation unit  630  may attenuate a level of the transmission signal and apply the signal into the RFID transmission selection unit  240  of the GSM RF unit  200 . 
     The RFID reception unit  700  may include a demodulator  710 , a power-division unit  720 , a low noise amplifier LNA 2  and a filter F 9 . 
     The filter F 9  may filter an output signal of the path selection unit  270  when the mobile communication terminal is in an RFID reception mode and a received signal from the antenna switch module  260  is transmitted to the RFID reception unit  700  via switch SW 2 . The low noise amplifier LNA 2  may amplify an output signal of the filter F 9 , and the power division unit  720  may divide a power level of an output signal of the low noise amplifier LNA 2  into two signals with a power-divided power level. 
     The demodulator  710  may include mixer M 3  and mixer M 4 , amplifier AMP 9  and amplifier AMP 10 , filter F 7  and filter F 8 , and amplifier AMP 11  and amplifier AMP 12 . The mixer M 3  and mixer M 4  may each receive a power-divided signal of the power division unit  720 , may demodulate the signals, and may downconvert the frequency of the signals. Downconverting a signal shall include shifting a frequency of a signal from a higher frequency band to a lower frequency band without significantly altering the content of the message, data, or information stored in the signal. The amplifier AMP 9  may amplify the output signal of the mixer M 3 , filter F 7  may filter the output signal of the amplifier AMP 9 , and the amplifier AMP 11  may amplify the output signal of the filter F 7 . Amplifier AMP 10  may amplify the output signal of the mixer M 4 , filter F 8  may filter the output signal of the amplifier AMP 10 , and amplifier AMP 12  may amplify the output signal of the filter F 8 . 
     Accordingly, the above-described circuitry may occupy a reduced area in the mobile communication terminal since it does not include the power amplifier PA 3 , the filter F 2 , the switching device SW 1  and the antenna  80  in the RFID RF unit  50  as shown in  FIG. 1 . 
     Also, the modulator  610  may upconvert the frequency band of the RFID transmission signal to be suitable for the GSM base band unit  100 , and the demodulator  710  may downconvert the frequency band of the RFID reception signal to be suitable for the GSM base band unit  100 . This may allow the mobile communication terminal to perform RFID communication with the RFID transception signal in an operating frequency band, such as a UHF frequency band, of the GSM base band unit  100 . The antenna switch module  260 , the amplifiers AMP 7  and AMP 8  and the power amplifier PA 5  may be configured to operate at the operating frequency band of the GSM base band unit  100 . 
       FIG. 3  shows a flow chart illustrating a method for processing a transception signal of the mobile communication terminal with the built-in RFID reader of  FIG. 2 . While method shown in  FIG. 3  is described for a GSM-based mobile communication terminal operating in a UHF frequency band, a similar method for processing transception signals for mobile communication terminals operating with other wireless protocols, such CDMA or W-CDMA, and in other frequency bands may be similarly performed, and the invention is not limited to the illustrated embodiment described herein. 
     As shown in  FIG. 3 , in step S 101 , a transmission signal transmitted from the GSM base band unit  100  may be encoded and signal-processed from a digital transmission signal into an analog signal by the RFID reader control unit  400 . 
     Next, in step S 102 , the transmission signal may be modulated and its frequency may be upconverted by the modulator  610 . Upconversion may shift the frequency of the transmission signal into an operating frequency of the GSM base band unit  100 , which may be the UHF frequency band. 
     The transmission signal may be amplified and filtered, and then transmitted to the RFID transmission selection unit  240  of the GSM RF unit  200 . 
     Next, in step S 103 , the transmission signal may be amplified to a high power through the power amplifier PA 5 , and may be transmitted through the antenna switch module  260  and the antenna  280  to an external RFID transponder (not shown). During step S 103 , the transmission signal may be further amplified through the power amplifier PA 5  so transception of the RFID transmission signal may be communicated at distances exceeding one meter. 
     Thereafter, in step S 104 , the GSM RF block  200  may receives a high frequency reception signal in the UHF band from an external RFID transponder (not shown). 
     In step S 105 , the path selection unit  270  may apply the high frequency reception signal received through the antenna  280  to the RFID reception unit  700 , which may then filter the signal through the filter F 9  and amplify the signal through the low noise amplifier LNA 2 . 
     The demodulator  710  may then downconvert the frequency to a lower frequency band in step S 106 . Specifically, the frequency of the high frequency reception signal may be downconverted to a frequency suitable for the RFID reader control unit  400 . 
     Next, in step S 107 , the demodulator  710  may demodulate the high frequency reception signal. The RFID reader control unit  400  may decode the demodulated reception signal, and may signal-process the reception signal to convert the analog reception signal into a digital reception signal. Finally, in step S 108 , the RFID reader control unit  400  may transmit the digital reception signal into the GSM base band unit  100 . 
     Then, the GSM base band unit  100  may perform additional operations related to information received from the RFID unit  300 , such as store the information or transmit the information to a database or computer terminal, where the information may be stored or may update a current status condition or data entry, over a GSM-based network. 
     As described above, according to an exemplary embodiment of the present invention, an RFID RF block and a GSM RF unit share an antenna, an antenna switch module and a high output amplifier of to minimize circuitry area consumption and cost of manufacturing. 
     Additionally, RFID transception is performed over a higher operating frequency band of the mobile communication terminal, such as a UHF band for GSM protocols, so that RFID communication may be performed over a longer distance to improve quality of communication. 
     It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.