KR101372112B1 - Radio Frequency IDentification transmitter/receiver device - Google Patents

Abstract

RFID transmitting and receiving device according to an embodiment is a first phase piece for generating a first oscillation signal and a second oscillation signal; An I measurement signal processor configured to generate an I (in-phase) measurement signal by mixing the first oscillation signal with a reception signal, and to process the I measurement signal; A Q measurement signal processor configured to generate a quadrature-phase (Q) measurement signal by mixing the second oscillation signal with a received signal and to process a Q measurement signal; And a control signal analysis module for analyzing the I measurement signal and the Q measurement signal to generate analysis information, and a channel multiplexing module for dividing an RFID frequency band into a predetermined bandwidth and coding a plurality of channels according to the analysis information. Include.

According to the embodiment, interference between the RFID channels can be eliminated through channel multiplexing, thereby improving the recognition distance, reception sensitivity, and recognition rate of the tag signal. In addition, the wavelength spacing of the multiple channels can be kept constant, thereby preventing nonlinear interference signals, a decrease in reception sensitivity, and an increase in SNR due to excessive PAR.

RFID, channel multiplexing, phase-lock circuit, attenuator, amplifier, phase shifter

Description

[0001] RFID TRANSMITTER [0002]

An embodiment discloses an RFID transceiver.

Ubiquitous network technology has attracted the attention of many people. Ubiquitous network technology means a technology that makes it possible to connect to various networks smoothly regardless of time and place.

Such a ubiquitous network may be implemented as a short range wireless communication device, for example, an RFID transceiver, and the RFID transceiver includes a tag attached to an article and embedded with article information, and a reader that reads information of the tag using RF communication.

Since readers communicate with dozens or hundreds of tags, it is easy to cause interference between channels, and especially nonlinear interference signals caused by excessive peak to average power rating (PAR) can adversely affect RFID communication. do.

In addition, in the case of the reader, the tag being moved is the target of communication, and thus, the reader is in an unstable reception environment due to various factors. First, when implemented using the ASK (Amplitude Shift Keying) modulation method through envelope detection, the recognition rate Second, the energy supply structure to the tag can be variously changed according to the type of modulation method. Third, the phase shift occurs or the reception angle is changed because the tag is moved at high speed. Fourth, for example, the same frequency band may be used for transmission and reception, and signal distortions such as phase inversion, recognition distance, and error rate may be differentially generated according to the separation and synthesis of I / Q signals during modulation. .

In particular, important parameters of signal recovery include gain flatness and output of a frequency band. If there is a difference in gain according to a wavelength, a power difference between channels occurs during amplification, and a signal with increased power By saturating the amplifier output, the signal of the other channel is weak.

Therefore, there is a problem that signal recovery becomes difficult.

The embodiment provides an RFID transceiver which can minimize interference occurring between RFID channels, extend a tag recognition distance, and improve tag supply and tag recognition rate (signal recovery rate).

RFID transmitting and receiving device according to an embodiment is a first phase piece for generating a first oscillation signal and a second oscillation signal; An I measurement signal processor configured to generate an I (in-phase) measurement signal by mixing the first oscillation signal with a reception signal, and to process the I measurement signal; A Q measurement signal processor configured to generate a quadrature-phase (Q) measurement signal by mixing the second oscillation signal with a received signal and to process a Q measurement signal; And a control signal analysis module for analyzing the I measurement signal and the Q measurement signal to generate analysis information, and a channel multiplexing module for dividing an RFID frequency band into a predetermined bandwidth and coding a plurality of channels according to the analysis information. Include.

The embodiment has the following effects.

First, the interference phenomenon between RFID channels can be eliminated through channel multiplexing within narrow frequency bands used in RFID technology, so that the recognition distance, reception sensitivity, and recognition rate of tag signals can be improved. There is.

Second, the wavelength spacing of the multiple channels can be kept constant, thereby preventing nonlinear interference signals, a decrease in reception sensitivity, and an increase in signal to noise ratio (SNR) due to excessive PAR.

Third, since the RFID signal can be precisely measured and analyzed for each channel, only a channel having a high signal recovery rate can be selectively used among the multiplexed channels, and an energy can be smoothly supplied to a tag.

An RFID transceiver according to an embodiment will be described with reference to the accompanying drawings. For convenience of description, the RFID transceiver according to the embodiment is an RFID reader using a UHF signal of about 900 MHz as a carrier signal.

1 is a block diagram schematically showing the components of the RFID transceiver 100 according to the embodiment, and FIG. 2 is a block diagram of the received signal power adjusting unit 110 of the RFID transceiver 100 according to the embodiment. It is a schematic block diagram.

Referring to FIG. 1, the RFID transceiver 100 according to the embodiment includes a reception antenna 101, a transmission antenna 102, a reception signal power adjusting unit 110, a first switch unit 105, and an Rx signal processing unit 120. ), I measurement signal processing unit 130, Q measurement signal processing unit 140, Tx signal processing unit 150, the first phase shifter 185, the second switch unit 170, the phase synchronization circuit unit 175, It comprises a three switch unit 180 and the control unit 160.

The received signal power adjusting unit 110 is connected between the receiving antenna 101 and the first switch unit 105, and the received signal is saturated due to the influence of the interference signal, the influence of the antenna gain, the influence of the amplification gain of the internal circuit. Adjust the power of the received signal to prevent the phenomenon.

Referring to FIG. 2, the received signal power controller 110 includes a first power amplifier (PA) 112, a first attenuator 114, and a first filter 116.

The first amplifier 112 amplifies the power of the received signal when the power of the received signal is less than the reference value, and the first attenuator 114 attenuates the power of the received signal when the power of the received signal reaches a maximum value. Let's do it. In addition, the first attenuator 114 may amplify the power of the down-adjusted received signal and adjust it upward by a predetermined width.

The control unit 160 receives the measurement signal from the I measurement signal processor 130 and the Q measurement signal processor 140 and analyzes the measurement signal. In this case, the first amplifier 112 and the first amplifier are sensed by sensing the power of the received signal. One attenuator 114 is controlled.

Referring to FIG. 1, the first switch unit 105 transmits the received signal transmitted from the received signal power adjusting unit 110 to the Rx signal processor 120, the I measurement signal processor 130, and the Q measurement signal processor 140. Branch optionally.

The first switch unit 105 may be provided as a divider, a circulator, a three-way divider circuit, or the like.

The Rx signal processor 120 converts the signal received through the reception antenna 101 into a baseband signal, demodulates it, and transmits the demodulated signal to the control unit 160.

The Tx signal processing unit 150 receives a transmission signal from the control unit 160, modulates it, converts it into an RF signal, and transmits the converted signal to the transmission antenna 102.

In addition, the I measurement signal processor 130 is a component that processes the received signal branched from the first switch unit 105 into a measurement signal in an I-in-phase signal state, and the Q measurement signal processor 140 Is a component that processes the branched received signal into a measurement signal in the state of a quadrature-phase signal.

The measurement signals processed by the I measurement signal processor 130 and the Q measurement signal processor 140 are transmitted to the controller 160 and used to generate analysis information.

Meanwhile, as the analysis information is generated, if the phase information and the power level of the current channel are determined to be unstable as the analysis information is generated, the controller 160 changes the initial frequency of the RFID channel in the 900 MHz band and newly codes 16 channels.

For example, when the recognition distance with the tag changes, the phase point at the point of time when the received signal reaches the antenna is changed. In particular, when there is a difference in gain between the I and Q signals depending on the wavelength, the amplification process occurs. In the power difference between the channels occurs.

When the power difference between the channels occurs, the amplifier output is saturated by the signal with the increased power, and the signal of the other channel is weak.

Therefore, the controller 160 can solve the problem caused by the tag recognition distance change and the problem caused by the interference signal through the channel multiplexing as described above.

The measurement signal analysis function and the channel multiplexing function of the controller 160 will be described later in detail with reference to FIG. 7.

When the channel is multiplexed, the controller 160 transmits a control signal to the phase synchronization circuit unit 175, and the phase synchronization circuit unit 175 generates a plurality of oscillation signals corresponding to the multiplexed channel.

The third switch unit 180 receives the oscillation signal from the phase synchronization circuit unit 175 and selectively branches, for example, may branch in two paths.

The oscillation signal may be transmitted to the first phase shifter 185 through the third switch unit 180 or to the Rx signal processing unit 120 and the Tx signal processing unit 150.

Hereinafter, the Rx signal processor 120 will be described with reference to FIG. 3.

3 is a block diagram schematically showing the components of the Rx signal processor 120 of the RFID transceiver 100 according to the embodiment.

Referring to FIG. 3, the Rx signal processor 120 includes a signal distributor 121, a second phase shifter 122, a first mixer 123, a second filter 124, a second mixer 125, And a third filter 126 and a demodulator 127.

The signal distribution unit 121 branches the received signal transmitted through the first switch unit 105 into two signals having the same power level and transfers the received signal to the first mixer 123 and the second mixer 125, respectively. .

The second phase shifter 122 is a circuit which shifts the phase of the oscillation signal transmitted from the third switch unit 180 into an I signal state and a Q signal state. The second phase shifter 122 may be implemented with a balloon circuit.

The second phase shifter 122 transmits the third oscillation signal in the I signal state to the first mixer 123 and the fourth oscillation signal in the Q signal state to the second mixer 125.

The first mixer 123 mixes one branched reception signal with a third oscillation signal and converts the signal into a baseband I signal, and the second mixer 125 converts the branched reception signal with the fourth oscillation signal. Mix and convert to baseband Q signal.

The second filter 124 and the third filter 126 respectively filter the baseband I signal and the baseband Q signal to remove noise components generated during the mixing process.

The demodulator 127 demodulates the filtered baseband I signal and the baseband Q signal into digital I signals and digital Q signals, respectively.

The demodulated digital I and digital Q signals are transmitted to the control unit 160 and interpreted as tag signals.

Hereinafter, the I measurement signal processor 130 will be described with reference to FIG. 4.

4 is a block diagram schematically illustrating components of an I measurement signal processor 130 of the RFID transceiver 100 according to the embodiment.

Referring to FIG. 4, the I measurement signal processor 130 may include a first separator 131, a third mixer 132, a fourth filter 133, a second amplifier 134, and a second attenuator 135. And a fifth filter 136 and a second separator 137.

The first isolator 131 prevents the reflected wave signal from flowing together when the received signal is branched from the first switch unit 105, and the second isolator 137 is configured to measure the I measurement signal. When it is transmitted to the second switch unit 170, it blocks the transmission of the reflected wave signal from the control unit 160 side.

The first phase shifter 185 shifts the phase of the oscillation signal transmitted from the third switch unit 180 to generate a first oscillation signal in an I signal state and a second oscillation signal in a Q signal state.

The first phase shifter 185 transmits the first oscillation signal to the third mixer 132 and the second oscillation signal to the fourth mixer 142 of the Q measurement signal processor 140.

The third mixer 132 mixes the received signal transmitted through the first switch unit 105 with the first oscillation signal to generate an I measurement signal in a digital signal state.

Since the measurement signal processor 130 does not include a demodulator, the first oscillation signal may be adjusted to generate a digital signal by a direct demodulation method.

The fourth filter 133 filters the I measurement signal to remove noise components generated in the mixing process.

The second amplifier 134 and the second attenuator 135 maintain or stabilize the reception sensitivity of the measurement signal by amplifying or attenuating the I measurement signal. In this case, the controller 160 determines the I measurement signal according to the analysis information. Detect the power level of the device and determine the reception sensitivity.

The controller 160 controls the amplification / attenuation of the second amplifier 134 and the second attenuator 135 by transmitting a control signal.

The fifth filter 136 removes noise components generated in the process of amplifying / attenuating the I measurement signal, and transmits the filtered I measurement signal to the second switch unit 170 through the second isolator 137. do.

Hereinafter, the Q measurement signal processing unit 140 will be described with reference to FIG. 5.

5 is a block diagram schematically illustrating components of the Q measurement signal processor 140 of the RFID transceiver 100 according to the embodiment.

Referring to FIG. 5, the Q measurement signal processor 140 includes a third isolator 141, a fourth mixer 142, a sixth filter 143, a third amplifier 144, a third attenuator 145, And a seventh filter 146 and a fourth separator 147.

The third isolator 141 blocks the inflow of the reflected wave signal when the received signal is branched from the first switch unit 105, and the fourth isolator 147 has a Q measurement signal for the second switch. When it is transmitted to the unit 170, it blocks the transmission of the reflected wave signal from the control unit 160 side.

The fourth mixer 142 receives the second oscillation signal from the first phase shifter 185 and mixes the received signal transmitted through the first switch unit 105 with the second oscillation signal to form a digital signal. Generates a Q measurement signal.

Like the third mixer 132, the fourth mixer 142 may generate a digital signal by direct demodulation by adjusting the second oscillation signal.

The sixth filter 143 filters the Q measurement signal to remove noise components generated during the mixing process.

The third amplifier 144 and the third attenuator 145 amplify or attenuate the Q measurement signal to maintain the reception sensitivity of the measurement signal in a stable state. At this time, the controller 160 controls the Q measurement signal according to the analysis information. Detect the power level of the device and determine the reception sensitivity.

The controller 160 controls amplification / attenuation of the third amplifier 144 and the third attenuator 145 by transmitting a control signal.

The seventh filter 146 removes noise components generated during amplification / attenuation of the Q measurement signal, and transmits the filtered Q measurement signal to the second switch unit 170 through the fourth isolator 147. do.

The second switch unit 170 selectively transmits the I measurement signal and the Q measurement signal to the control unit 160, and may be provided as a divider, a circulator, a two-way divider circuit, and the like. .

Since the fourth filter 133 and the sixth filter 143 perform a function of filtering the entire channel of the 900 MHz band, the fourth filter 133 and the sixth filter 143 may be provided as band pass filters, and the fifth filter 136 and the seventh filter 146. ) Should be accurately filtered for each channel, so it should be filtered with a channel interval of 200 KHz.

Hereinafter, the Tx signal processor 150 will be described with reference to FIG. 6.

6 is a block diagram schematically illustrating components of the Tx signal processor 150 of the RFID transceiver 100 according to the embodiment.

Referring to FIG. 6, the Tx signal processor 150 may include a modulator 151, an eighth filter 152, a ninth filter 155, a fifth mixer 153, a sixth mixer 156, and a third phase. The shifter 154, the signal synthesizer 157, the tenth filter 158, and the fourth amplifier 159 are included.

The modulator 151 modulates a digital signal into a baseband signal including a D / A converter, a modulation circuit, and the like. At this time, the modulation format may be applied to the PIE format according to the UHF RFID Protocol such as ISO 18000-A, ISO 18000-B, Electronic Product Code (EPC) Generation-0, EPC Generation-1, EPC Generation-2.

As the modulation standard is applied, the RFID transceiver 100 according to the embodiment has a double sideband-amplitude shift keying (DSB-ASK), a single sideband-amplitude shift keying (SSB-ASK), and phase reversal-amplitude (PR-ASK). Shift demodulation method such as Shift Keying can be used.

If it is determined that the phase point of the I measurement signal and the Q measurement signal has changed along with the tag recognition distance as a result of the analysis of the measurement signal, the controller 160 needs to synchronize the phases of the I transmission signal and the Q transmission signal based on this. Generates phase adjustment information and transmits it to the modulator 151.

The modulator 151 modulates a transmission signal by adjusting a voltage level according to the phase adjustment information. Therefore, the phases of the I transmission signal and the Q transmission signal can be synchronized, and the voltage and gain values between the two signals can also be processed evenly without being saturated to one side.

The eighth filter 152 and the ninth filter 155 filter the I and Q signals transmitted from the modulator 151 according to the channel bandwidth, respectively, and the filtered I and Q signals are combined in the fifth mixer 153. ) And the sixth mixer 156.

The third phase shifter 154 shifts the phase of the oscillation signal transmitted from the third switch unit 180 to generate a fifth oscillation signal in an I signal state and a sixth oscillation signal in a Q signal state.

The third phase shifter 154 transfers the fifth oscillation signal to the fifth mixer 153, and transfers the sixth oscillation signal to the sixth mixer 156.

The fifth mixer 153 mixes the fifth oscillation signal with the I transmission signal transmitted from the control unit 160 to generate the RF I transmission signal, and the sixth mixer 156 generates the sixth oscillation signal with the Q transmission signal. Mix and generate the RF Q transmission signal.

The signal synthesizing unit 157 synthesizes the RF I transmission signal and the RF Q transmission signal into a single RF transmission signal, and the tenth filter 158 removes noise components generated in the synthesis process.

The transmission signal filtered by the tenth filter 158 is amplified to a power level transmittable by the fourth amplifier 159 and transmitted to the tag through the transmission antenna 102.

Hereinafter, the control unit 160 will be described in detail.

FIG. 7 is a block diagram schematically illustrating components of the control unit 160 of the RFID transceiver 100 according to the embodiment, and FIG. 8 is a graph of monitoring the first measurement signal of the control unit 160 according to the embodiment. 9 is a graph illustrating a modulation state diagram of a first measurement signal according to an embodiment.

10 is a graph illustrating monitoring of the second measurement signal of the controller 160 according to the embodiment, and FIG. 11 is a graph illustrating a modulation state diagram of the second measurement signal according to the embodiment.

Referring to FIG. 7, the controller 160 includes a channel multiplexing module 161, a PLL control module 162, a phase adjustment module 163, a measurement signal analysis module 164, and a reception sensitivity adjustment module 165. It is configured by.

The measurement signal analysis module 164 analyzes the I measurement signal and the Q measurement signal through the second switch unit 170 to generate analysis information.

The analysis information includes a voltage level, a power, a phase, a recognition distance with a tag, and whether or not interference between channel signals of the measurement signal.

The measurement signal analysis module 164 includes a specification table according to signal states to generate analysis information. The measurement signal analysis module 164 processes a filtering operation to convert a signal format and extract necessary information to analyze a measurement signal.

As shown in FIG. 8, as a result of analyzing the first measurement signal, the Q measurement signal a1 is in a recoverable state and the I measurement signal b1 is analyzed in a state that cannot be restored.

This is because when the recognition distance with the tag changes, first, the phase point at the point of time when the received signal reaches the antenna is changed, and second, when there is a difference in gain between the I and Q signals according to the wavelength, amplification is performed. This is because a power difference is generated between channels in the process.

Referring to FIG. 9, 0 °, 270 °, 180 °, in the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, respectively, based on the "0" point of the x-axis and the "0" point of the y-axis as reference axes. I measurement signals and Q measurement signals having a phase of 90 ° are shown.

In addition, the measurement signal is represented by a different symbol for each channel, it can be seen that the difference depending on the phase and the timing (timing) and is dispersed throughout the mapping surface.

This means that the difference in phase and synchronization time is generated according to the change of the tag recognition distance. In this case, the signal recovery rate is significantly lowered.

Accordingly, the channel multiplexing module 161 changes the initial frequency of the RFID channel of the 900 MHz band according to the analysis information to newly code 16 channels.

In this case, the initial frequency may be randomly changed within the RFID frequency band, and the initial frequency may be multiplexed within about 910 MHz to 914 MHz band.

For example, if the initial frequency of the first measurement signal, that is, the start frequency of the first channel was 910.8 MHz, the channel multiplexing module 161 sets 910.9 MHz as the new initial frequency, and sets 15 channels having a 200 KHz bandwidth therefrom. Can be defined

According to the embodiment, since the initial frequency may be randomly changed and the channels may be multiplexed, tens to hundreds of different channel sets may be configured as necessary.

As such, the multiplexed channel may have a transmission rate of 40 Kbps to 640 Kbps, and as the number of channels increases, the recognition rate may decrease and the gain difference depending on the wavelength may be significantly reduced.

Meanwhile, as the channels are multiplexed, the PLL control module 162 transmits a control signal for commanding the oscillation signal change to the phase synchronization circuit unit 175 and the phase synchronization circuit unit 175 generates an oscillation signal corresponding to the new channel. The oscillation signal may be largely divided into signals for the I measurement signal processor 130 and the Q measurement signal processor 140, and signals for the Tx signal processor 150 and the Rx signal processor 120.

By changing the initial frequency f as described above, it is possible to cope with the change in the tag recognition distance [lambda], but it is difficult to cope with the change in the phase point at the time of antenna reception.

Accordingly, the phase adjustment module 163 generates phase adjustment information and transmits the phase adjustment information to the modulator 151. The modulator 151 adjusts the phase of the signal by adjusting the voltage level of the signal as described above. As the phase is adjusted, the phase between the I and Q signals can be synchronized and interpretable.

The reader signal is transmitted using the newly coded and phase-synchronized channel, and when a signal is received from the tag, a new measurement signal is generated through the above-described process.

The controller 160 interprets the new measurement signal to generate analysis information.

Referring to FIG. 10, unlike the case of FIG. 8, it is shown that the I measurement signal b2 is synchronized to have a phase difference of exactly 90 degrees with the Q measurement signal a2, and the voltage levels are adjusted to be balanced. Can be.

Therefore, both the Q measurement signal a2 and the I measurement signal b2 are recoverable.

In addition, referring to FIG. 11, it can be seen that the measurement signals represented by different symbols for each channel are concentrated at four regions of the mapping surface with equal intervals.

This means that the channel-specific signals meet the same recognition distance, synchronized phase and time specifications.

Meanwhile, the reception sensitivity adjustment module 165 compares the power of the measurement signal with a reference value according to the analysis information, and determines whether the measurement signal is amplified or attenuated.

When it is determined whether the amplification / attenuation of the measurement signal is determined, the reception sensitivity adjustment module 165 generates a control signal and transmits a control signal to the I measurement signal processor 130 and the Q measurement signal processor 140 to measure the I measurement signal. And adjust the power of the Q measurement signal.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications other than those described above are possible. For example, each component specifically shown in the embodiments of the present invention can be modified and implemented. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

1 is a block diagram schematically showing the components of an RFID transceiver according to an embodiment.

2 is a block diagram schematically illustrating the components of a received signal power adjusting unit of an RFID transceiver device according to an embodiment;

3 is a block diagram schematically illustrating components of an Rx signal processor of an RFID transceiver device according to an embodiment;

Figure 4 is a block diagram schematically showing the components of the I measurement signal processing unit of the RFID transceiver device according to the embodiment.

5 is a block diagram schematically illustrating components of a Q measurement signal processing unit of an RFID transceiver device according to an embodiment;

6 is a block diagram schematically illustrating components of a Tx signal processor of an RFID transceiver device according to an embodiment;

7 is a block diagram schematically illustrating components of a control unit of an RFID transceiver device according to an embodiment.

8 is a graph monitoring a first measurement signal of a controller according to an embodiment.

9 is a graph showing a modulation state diagram of a first measurement signal according to an embodiment.

10 is a graph monitoring a second measurement signal of a controller according to an embodiment.

11 is a graph illustrating a modulation state diagram of a second measurement signal according to an embodiment.

Claims (13)

A reception signal power adjusting unit connected to the reception antenna and configured to adjust power of a reception signal including a first amplifier and a first attenuator; A first phase shifter for generating a first oscillation signal and a second oscillation signal; An I measurement signal processor configured to generate an I (in-phase) measurement signal by mixing the first oscillation signal with the received signal and to process the I measurement signal; A Q measurement signal processor configured to generate a quadrature-phase (Q) measurement signal by mixing the second oscillation signal with the received signal and to process the Q measurement signal; And A measurement signal analysis module for analyzing the I measurement signal and the Q measurement signal to generate analysis information, and a controller including a channel multiplexing module for dividing an RFID frequency band into a predetermined bandwidth and coding a plurality of channels according to the analysis information; RFID transceiver. delete The method of claim 1, An Rx signal processor converting and demodulating the received signal and transmitting the demodulated signal to the controller; And And a Tx signal processing unit for receiving a transmission signal from the control unit, modulating and converting the transmission signal, and transmitting the modulation signal to a transmission antenna. The method of claim 3, wherein the Rx signal processing unit A signal distribution unit for distributing the received signal to branch the first received signal and the second received signal; A second phase shifter generating a third oscillation signal and a fourth oscillation signal; A first mixer configured to generate an I received signal by mixing the third oscillation signal with the first received signal; A second mixer for generating a Q received signal by mixing the fourth oscillation signal with the second received signal; And And a demodulator for demodulating the I received signal and the Q received signal and transmitting the demodulated signal to the controller. The method of claim 3, And a first switch unit connected to the received signal power adjusting unit and selectively branching the received signal to the Rx signal processing unit, the I measurement signal processing unit, and the Q measurement signal processing unit. The method of claim 1, wherein the I measurement signal processing unit A third mixer configured to generate an I measurement signal by mixing the first oscillation signal with the received signal; A second amplifier for amplifying the power of the I measurement signal under control of the controller; And a second attenuator configured to attenuate power of the I measurement signal under control of the controller. The method of claim 6, wherein the I measurement signal processing unit A first isolator connected to the front end of the third mixer; And And a second isolator connected to a rear end of the second attenuator. The method of claim 1, And a second switch unit connected to the I measurement signal processing unit and the Q measurement signal processing unit and selectively transferring the I measurement signal and the Q measurement signal to the controller. The method of claim 3, wherein the Tx signal processing unit A modulator for receiving the I transmission signal and the Q transmission signal from the control unit and modulating the transmission signal; A third phase shifter generating a fifth oscillation signal and a sixth oscillation signal; A fifth mixer for mixing the fifth oscillation signal with the I transmission signal to generate an RF I transmission signal; A sixth mixer for mixing the sixth oscillation signal with the Q transmission signal to generate an RF Q transmission signal; And And a signal synthesizing unit for synthesizing the RF I transmission signal and the RF Q transmission signal into a single RF transmission signal. The method of claim 3, A phase synchronization circuit unit generating a plurality of oscillation signals corresponding to the coded channels under the control of the controller; And a third switch unit for selectively transmitting the oscillation signal to at least one component of the I measurement signal processor, Q measurement signal processor, Rx signal processor, and Tx signal processor. The method of claim 3, The control unit may include a phase adjusting module for generating phase adjustment information according to the analysis information; A phase locked loop (PLL) control module for transmitting a control signal for generating a plurality of oscillation signals corresponding to the coded channels to a phase synchronization circuit unit; Of the reception sensitivity adjustment module for adjusting the reception sensitivity of the I measurement signal and the Q measurement signal by transmitting a control signal to the I measurement signal processor and the Q measurement signal processor to adjust the power of the I measurement signal and the Q measurement signal. Contains one or more modules, And the Tx signal processor adjusts and modulates a voltage level of a transmission signal according to the phase adjustment information. The method of claim 1, wherein the analysis information And at least one of a voltage level, a power, a phase, a recognition distance with a tag, and interference between channel signals of the I measurement signal and the Q measurement signal. The method of claim 1, wherein the channel multiplexing module Change the initial frequency according to the analysis information, divide the RFID frequency band into the predetermined bandwidth from the changed initial frequency, RFID transmitting and receiving device for randomly changing the initial frequency within the RFID frequency band.

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