KR100828909B1 - Detection system for condition of radio frequency signal - Google Patents

Abstract

An RF(Radio Frequency) signal state detection system is provided to control the power of a transmission signal not to generate an interference signal, thereby stably restoring/processing a receiving signal and improving a recognition distance, receive sensitivity, and a recognition rate of a communication device. A receiving antenna(105) and a transmission antenna(110) are respectively comprised. An interference signal measurer(120) generates data for interference signal analysis by processing a receiving signal. A fine oscillation measurer(150) generates data for fine oscillation signal analysis by processing the receiving signal. A power setup unit sequentially delivers plural transmission signals whose power levels are controlled to the transmission antenna. When the data for interference signal analysis and fine oscillation signal analysis are delivered, a controller(155) generates power level control information to deliver the generated information to the power setup unit.

Description

RF signal state detection system {Detection system for condition of Radio Frequency signal}

1 is a block diagram schematically illustrating the components of an RF signal state detection system according to an embodiment;

Figure 2 is a block diagram schematically showing the components of the interference signal measuring unit of the RF signal state detection system according to an embodiment.

3 is a graph illustrating interference signal analysis data measured by an interference signal measuring unit according to an exemplary embodiment.

Figure 4 is a block diagram schematically showing the components of the micro oscillation measuring unit of the RF signal state detection system according to an embodiment.

FIG. 5 is a graph illustrating data for analyzing a micro oscillation signal measured by a micro oscillation measuring unit according to an embodiment. FIG.

6 is a block diagram schematically illustrating components of a power setting unit in an RF signal state detection system according to an embodiment;

<Explanation of symbols for main parts of drawing>

100: RF signal state detection system 105: receiving antenna

110: transmit antenna 115: first switch unit

120: interference signal measuring unit 125: fifth switch unit

132: low noise amplifier (LNA) 134: receiving filter

136: second switch unit 140: Rx signal processing unit

145: phase synchronization circuit unit 150: fine oscillation measuring unit

155: control unit 160: Tx signal processing unit

165: third switch unit 172: power amplification module (PAM)

174: transmission filter 176: fourth switch unit

180: power setting unit 185: display unit

An embodiment of the present invention discloses an RF signal state detection system.

Currently, various mobile communication systems such as mobile phones, personal digital assistants (PDAs), smart phones, digital multimedia broadcasting (DMB) phones, and local area network (LAN) terminals are used.

In addition, ubiquitous (ubiquitous) network technology has attracted the attention of many people, ubiquitous network technology refers to a technology that allows to naturally connect to various networks regardless of time and place.

An example of such ubiquitous network technology is RFID technology, and among them, RFID technology introduced in commerce is representative.

A commercial RFID system consists of a tag attached to a product and a tag with detailed information, and a reader that reads the tag information using RF communication.The logistics / distribution management such as distribution, assembly, price change, and sale of the product can be efficiently handled. Provides a foundation to be

However, mobile communication systems and ubiquitous systems have differences in communication characteristics due to factors such as the fact that a plurality of terminals are distributed in various regions, interworking with various kinds of antennas, and having mobility. This results in lowering the performance and shortening the lifespan.

For example, in the case of RFID readers, tags that move at a high speed are severely affected by changes in the radio wave environment, for example, a phase change of a tag signal generated when the tags are moved. Has a big impact on the recognition rate.

When there are many tags in a region where multiple RFID readers are installed, tag signals using the same frequency band may be simultaneously received by the RFID readers. In this case, interference between tag signals may occur and the RFID reader may detect a signal. There is a problem that can not be processed and the data recognition rate is further lowered.

In addition, when the isolation signal between the transmitting and receiving antennas is not secured and its own transmission signal is received or when a transmission signal of another RFID reader is received, it becomes an interference signal, making processing of the reception signal difficult.

In addition, when the power intensity of the transmission signal is adjusted for smooth RF communication, the influence may extend to the internal circuit, particularly the receiver circuit, which may deteriorate a communication function such as causing a fine oscillation phenomenon.

The embodiment provides an RF signal state detection system capable of identifying appropriate transmission powers of a mobile communication system and a ubiquitous system by identifying a state of a transmission signal when an interference phenomenon occurs, and identifying the position of each system.

In addition, the embodiment provides an RF signal state detection system that can detect the interference phenomenon and control the transmission power so as to secure the isolation of the transmitting and receiving antenna.

In addition, the embodiment provides an RF signal state detection system for selecting the appropriate transmission power by determining whether the micro oscillation in the system.

The RF signal state detection system according to an embodiment includes at least one receiving antenna and one transmitting antenna; An interference signal measuring unit configured to process the received signal to generate data for analyzing the interference signal; A fine oscillation measuring unit configured to process the received signal and generate data for analyzing the fine oscillation signal; A power setting unit for sequentially transmitting a plurality of transmission signals whose power levels are adjusted to the transmission antennas; And a controller configured to generate power level adjustment information and transmit the generated power level adjustment information to the power setting unit when the interference signal analysis data and the micro oscillation signal analysis data are transferred.

Hereinafter, an RF signal state detection system according to an embodiment will be described in detail with reference to the accompanying drawings.

The RF signal state detection system according to the embodiment may be implemented on a mobile communication system or a ubiquitous system, and may also be implemented in the form of individual measurement equipment to measure radio signals such as CDMA signals and RFID signals.

In addition, when the RF signal state detection system according to the embodiment is implemented as a separate measurement equipment, by having the same internal circuit as the mobile communication system or ubiquitous system, it is possible to detect the internal circuit state of each communication equipment, such as micro oscillation phenomenon, etc. have.

For convenience of description below, the detection system according to the embodiment is implemented on an RFID reader.

1 is a block diagram schematically illustrating components of an RF signal state detection system 100 according to an embodiment.

Referring to FIG. 1, an RF signal state detection system (hereinafter referred to as a “detection system”) 100 according to an embodiment includes a reception antenna 105, a transmission antenna 110, a first switch unit 115, and a second. Switch unit 136, third switch unit 165, fourth switch unit 176, fifth switch unit 125, interference signal measuring unit 120, low noise amplifier (LNA) (132) , Reception filter 134, Rx signal processing unit 140, fine oscillation measurement unit 150, phase synchronization circuit unit 145, transmission filter 174, power amplifier module (PAM) 172, power The setting unit 180, the Tx signal processing unit 160, the control unit 155, and the display unit 185 are included.

Before explaining each component, the signal path of the detection system 100 will be described for convenience of understanding.

The detection system 100 has six signal paths. First, a path for measuring an interference signal of a received signal (hereinafter referred to as a “first path”), and second, for processing a received signal as communication data. Path (hereinafter referred to as "second path"), third, path for measuring whether the received signal is finely oscillated (hereinafter referred to as "third path"), and fourth, path for processing the transmission signal as communication data. (Hereinafter referred to as "fourth path"), fifth, a path for supplying transmission signals of various power levels (hereinafter referred to as "the fifth path") for the measurement of interference signals or micro oscillation measurement, and sixth, oscillation There is a path (hereinafter referred to as "sixth path") for distributing / delivering the frequency signal.

First, the first path will be described.

The reception antenna 105 receives a signal transmitted from a tag, another reader, the transmission antenna 110, and the like and transmits the signal to the first switch unit 115.

The receiving antenna 105 and the transmitting antenna 110 may be provided with one or more.

The first switch 115 branches the signal received from the receiving antenna 105 into two paths and transfers one of them to the interference signal measuring unit 120.

2 is a block diagram schematically showing the components of the interference signal measuring unit 120 of the RF signal state detection system 100 according to an embodiment.

The interference signal measuring unit 120 processes a received signal to generate data for interference signal analysis and transmits the data to the controller 155. Referring to FIG. 2, a first amplifier (PA; 122), a first mixer 124, a first signal detector 126, and a comparator 128.

The first amplifier 122 amplifies the signal transmitted from the first switch unit 115 into a detectable signal range, and the first mixer 124 converts the amplified signal into a signal of an intermediate frequency band.

The phase synchronization circuit unit 145 generates a plurality of oscillation frequency signals having a predetermined frequency interval under the control of the controller 155, and sequentially transmits them to the fifth switch unit 125.

Therefore, the interference signal measuring unit 120 may inspect signals of various channels.

The fifth switch unit 125 branches the oscillation frequency signal and transfers the oscillation frequency signal to the first mixer 124.

The first mixer 124 mixes the oscillation frequency signal transmitted from the fifth switch unit 125 with the received signal and converts it into an intermediate frequency signal.

The first signal detecting unit 126 may be provided as, for example, a log amplifier, and outputs an intermediate frequency signal in an analog state as a DC voltage signal, thereby converting the power level into a state capable of detecting a power level.

In this case, the first signal detection unit 126 may extend the signal sensitivity range of the power level that can be received by outputting the intermediate frequency signal as a DC voltage signal proportional to a direct decibel value.

The control unit 155 transmits the reference voltage differentiated according to a specification such as a type of RFID radio standard or an allocated frequency for each country to the comparator 128.

The comparator 128 generates comparison information by comparing the voltage of the power level signal transmitted from the first signal detection unit 126 with a reference voltage, and transmits the comparison information to the control unit 155. The comparison information is an interference signal analysis. Used for data.

3 is a graph illustrating interference signal analysis data measured by the interference signal measuring unit 120 according to an exemplary embodiment.

The controller 155 analyzes the comparison information to determine whether an interference signal is present. Referring to FIG. 3, a comparison signal B section in a normal range and a comparison signal A section in an abnormal range exist.

Therefore, the controller 155 may analyze the presence or absence of the interference signal, the feedback level of the transmission signal, the reflection value based on the reflection coefficient, and the like by analyzing the "A" signal. Can be used to calculate the degree of isolation between each other), the degree of isolation between other communication equipment, the location of the communication equipment, and the like.

For example, when the "A" signal has a power level of 30 dbm, the controller 155 may determine that the detection system 100 is located at a distance of about 6 m from the external communication equipment.

The control unit 155 generates power level adjustment information according to the analysis result, and transmits it to the power setting unit 180.

Next, the second path will be described.

A signal branched to a line different from the interference signal measuring unit 120 among the signals branched from the first switch unit 115 is transmitted to the low noise amplifier 132.

The low noise amplifier 132 suppresses and amplifies the noise component of the transmitted signal, and the reception filter 134 blocks the signal of the mixed noise component in the amplification process.

The second switch unit 136 selectively transfers the filtered received signal to the Rx signal processor 140 and the fine oscillation measuring unit 150. The second and third paths are controlled by the second switch unit 136. Signal processing by may proceed.

The Rx signal processor 140 receives the branched signal, demodulates it, and transmits the demodulated signal to the controller 155. The demodulated signal is signal-processed by the control unit 155 into communication data.

Although not shown in the drawing, the Rx signal processor 140 may be composed of a balloon circuit, an I signal mixer, a Q signal mixer, a demodulator, and the like. The Rx signal processor 140 may receive an oscillation frequency signal and a received signal transmitted from the phase synchronization circuit 145. Synthesize and generate a baseband signal.

When the phase synchronization circuit unit 145 generates the oscillation frequency signal, the fifth switch unit 125 branches it to the Rx signal processor 140.

The fifth switch unit 125 branches the oscillation frequency signal to each component under the control of the controller 155, and the fifth switch unit 125 branches the oscillation frequency signal into two signal paths. One path is connected to the interference signal measuring unit 120 and the fine oscillation measuring unit 150.

In addition, the other path of the fifth switch unit 125 is connected to the Rx signal processor 140 and the Tx signal processor 160.

In this way, the sixth path is configured by the fifth switch unit 125.

The balloon circuit separates the phase-inverted received signal into an I signal (eg, "E sin ωt") and a Q signal (eg "E cos ωt").

The I signal mixer and the Q signal mixer are dual mixers, and combine I baseband signals (I ⁺ and I ⁻ signals) and Q baseband signals (Q ⁺ signals and Q ⁻ signals) each having a phase difference of 90 degrees.

The demodulator includes an analog to digital converter (ADC) to demodulate the baseband I signal and the baseband Q signal into digital signals having a plurality of polarities.

Next, the third path will be described.

The received signal branched by the second switch unit 136 is transmitted to the fine oscillation measuring unit 150, and the fine oscillation measuring unit 150 processes the received signal to generate data for analyzing the fine oscillation signal.

4 is a block diagram schematically illustrating components of the micro oscillation measuring unit 150 of the RF signal state detection system 100 according to an exemplary embodiment.

Referring to FIG. 4, the fine oscillation measuring unit 150 includes a second mixer 152 and a second signal detecting unit 154, and the second mixer 152 includes a fifth switch unit 125. The oscillation frequency signal transmitted from is mixed with the received signal and converted into an intermediate frequency signal.

The intermediate frequency signal converted by the second mixer 152 corresponds to a fine oscillation signal region.

The second signal detection unit 154 may be provided as, for example, a log amplifier, and outputs an intermediate frequency signal in an analog state as a DC voltage signal, thereby converting the power level into a state capable of detecting a power level.

The power level information generated by the second signal detection unit 154 is used as the data for the fine oscillation signal analysis, and because the signal characteristics are different from the data for analyzing the interference information, the signal is not required without an additional circuit such as the comparator 128. Analysis is possible.

5 is a graph showing data for analyzing the micro oscillation signal measured by the micro oscillation measuring unit 150 according to the embodiment.

The control unit 155 receives the power level information from the second signal detection unit 154, and compares the power level information with the noise ripple reference voltage allowed in the system.

In an embodiment, the received signal is processed by ASK (Amplitude Shift Keying) modulation using envelope detection, and the fine oscillation signal is measured in the form of a binary signal as shown in FIG. 5.

Before comparing the reference voltage and the power level information, the controller 155 corrects the offset of the received signal to synchronize the initial value (“0” level) of the signal to be compared with the reference voltage.

As a result of the comparison, if there is a signal section exceeding the reference voltage, the controller 155 determines that the micro oscillation has occurred, and generates power level adjustment information.

That is, when the transmission signal is amplified more than necessary, a fine oscillation phenomenon may occur in the receiver circuit due to the internal oscillation phenomenon even without the influence of external signals such as the reflected signal and the received signal.

In this case, problems such as deterioration of reception performance and shortening of the life of the circuit may occur.

The controller 155 may simultaneously transmit power level adjustment information to the Tx signal processor 160 and the power setting unit 180. The Tx signal processor 160 adjusts the power of the transmission signal according to the power level information. Therefore, performance degradation of the internal circuit can be prevented.

Also, in the case of the power setting unit 180, the interference signal measuring unit 120 and the fine oscillation measuring unit 150 may perform the measurement function on the next signal level by sequentially adjusting the power of the test transmission signal. have.

Next, the fourth path will be described.

The Tx signal processor 160 modulates the digital transmission signal transmitted from the control unit 155 with the oscillation frequency signal transmitted from the fifth switch unit 125 into a transmission signal in an analog signal state. The Tx signal processor 160 may include a D / A converter, an amplifier, and the like implemented with a mixer, a diode, and the like.

As described above, the Tx signal processor 160 adjusts the amplification level in the modulation process based on the power level adjustment information of the controller 155.

In this case, the Tx signal processor 160 may perform modulation according to a pulse-interval encoding (PIE) signal standard according to an RFID protocol such as ISO 18000-6A, ISO 18000-6B, ISO 18000-6C, or the like.

The modulated transmission signal is transmitted to the power amplifier module 172 through the third switch unit 165.

The power amplification module 172 amplifies the modulated transmission signal in a state capable of outputting, and the amplified signal is transmitted to the fourth switch unit 176 after the unwanted component signal is removed through the transmission filter 174. .

The fourth switch unit 176 branches the signal path to the transmission filter 174 to receive the transmission signal, and transmits it to the transmission antenna 110.

Next, the fifth route will be described.

6 is a block diagram schematically illustrating the components of the power setting unit 180 of the RF signal state detection system 100 according to an embodiment.

The power setting unit 180 sequentially transmits a plurality of transmission signals whose power levels are adjusted, that is, test transmission signals to the transmission antenna 110, and through this operation, the interference signal measuring unit 120 and the fine oscillation. The measurement unit 150 may perform a measurement function with respect to various transmission signals.

The third switch unit 165 receives the transmission signal in the analog state from the Tx signal processing unit 160 and transmits the transmission signal to the power setting unit 180 through a path opening and closing operation.

As shown in FIG. 6, the power setting unit 180 includes a plurality of attenuators 182 and 184 connected to each other, and adjusts power of a transmission signal according to power level adjustment information transmitted from the control unit 155. do.

The power setting unit 180 gradually attenuates the power of the transmission signal or amplifies the attenuated power again according to the power level adjustment information.

The test transmission signal whose power is adjusted in this way is transmitted to the transmission antenna 110 through the path opening and closing operation of the fourth switch unit 176.

For example, the first switch unit 115 to the fifth switch unit 125 may be implemented as a semiconductor circuit such as a single pole double throw (SPDT) device.

The control unit 155 transmits a control signal to each of the switch units 115, 136, 165, 176, and 125 so that the switching operation can be synchronized. For example, the first switch unit 115 may include an interference signal measuring unit ( In the case where the path is determined by reference numeral 120, the path of the fifth switch unit 125 may be matched to the interference signal measurement unit 120.

The controller 155 has a communication protocol to control wireless communication with the tag, and processes the signal transmitted from the Rx signal processor 140 into a digital signal.

In addition, the controller 155 transmits the digitally processed signal to the Tx signal processor 160 such as data coding / decoding, format conversion, and filtering operation. The controller 155 may be implemented using a field programmable gate array (FPGA) circuit or a digital signal processing (DSP) circuit.

In addition, the controller 155 transmits an analysis result of the interference signal analysis data and the micro oscillation signal analysis data to the display unit 185, and the display unit 185 processes the transmitted analysis result as a video signal. And display on the GUI (Graphic User Interface) screen.

The main operations of the RF signal state detection system 100 according to the above embodiments are summarized as follows.

The power setting unit 180 adjusts the power level of the test transmission signal, and the test transmission signal is transmitted to the transmission antenna 110.

The interference signal measuring unit 120 measures the presence of an interference signal by measuring the received signal for each channel, and the interference signal may be a signal received from the outside or the test transmission signal.

If it is determined that an interference signal exists, the controller 155 transmits the power level adjustment information to the power setting unit 180, and the power setting unit 180 sequentially adjusts and provides a test transmission signal.

Accordingly, the power setting unit 180 and the interference signal measuring unit 120 are interlocked and cyclically operated, and thus it is possible to test whether a transmission signal having various power levels acts as an interference signal.

On the other hand, the fine oscillation measuring unit 150 measures whether the receiving end of the fine oscillation with respect to the test transmission signal, and when it is determined that the micro oscillation is present, the control unit 155 transmits the power level adjustment information to the power setting unit 180 To pass.

The power setting unit 180 sequentially adjusts and provides a test transmission signal.

Accordingly, the power setting unit 180 and the fine oscillation measuring unit 150 are interlocked and cyclically operated to test the influence of the transmission signal having various power levels on the fine oscillation.

This is a description of the interlocking relationship between the interference signal measuring unit 120, the fine oscillation measuring unit 150, and the power setting unit 180, the interference signal measuring unit 120 and the fine oscillation measuring unit 150 for the test As described above, the measurement may be performed on the signal received from the outside and the signal state may be analyzed separately from the transmission signal.

Although described above with reference to the embodiments, which are merely examples and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains are not exemplified above without departing from the essential characteristics of the present invention. It will be appreciated that many variations and applications are possible. For example, each component specifically shown in the embodiment of the present invention can be modified. 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.

According to the RF signal state detection system according to an embodiment of the present invention, it is possible to adjust the power of the transmission signal so that no interference signal is generated, so that the received signal can be stably restored / processed, the recognition distance of the communication equipment, the reception sensitivity, There is an effect that can improve the recognition rate.

In addition, according to an embodiment of the present invention, it is possible to prevent the micro-oscillation phenomenon has the effect of improving the performance of the communication equipment and protect the internal circuits to extend the life.

In addition, according to the embodiment of the present invention, there is an effect that can ensure the isolation between the communication equipment and the isolation between the transmission and reception antennas.

In addition, according to an embodiment of the present invention, it is possible to identify and arrange the optimum position of the communication equipment or antenna that does not cause interference, and there is an effect of efficiently constructing a network.

Claims (17)

At least one receiving antenna and one transmitting antenna; An interference signal measuring unit configured to process the received signal to generate data for analyzing the interference signal; A fine oscillation measuring unit configured to process the received signal and generate data for analyzing the fine oscillation signal; A power setting unit for sequentially transmitting a plurality of transmission signals whose power levels are adjusted to the transmission antennas; And And a controller configured to generate power level adjustment information and transmit the generated power level adjustment information to the power setting unit when the interference signal analysis data and the micro oscillation signal analysis data are transmitted. The method of claim 1, RF signal state detection system including a first switch unit for branching a received signal to the interference signal measuring unit and the fine oscillation measuring unit. The method of claim 1, RF signal state detection system including an Rx signal processing unit for demodulating the received signal to deliver to the control unit. The method of claim 3, And a second switch unit for branching a received signal to the Rx signal processor and the fine oscillation measuring unit. The method of claim 4, wherein RF signal state detection system is connected to one or more circuits of a low noise amplifier, a filter in front of the second switch unit. The method of claim 1, wherein the control unit RF signal state detection system for generating the isolation information according to the mobile communication environment by analyzing the interference signal analysis data, and generating the detection information of the micro oscillation signal by analyzing the micro oscillation signal analysis data. The method of claim 1, RF signal state detection system including a display unit for receiving and displaying the analysis results of the interference signal analysis data and the fine oscillation signal analysis data from the controller. The method of claim 1, A Tx signal processor for modulating the transmission signal transmitted from the controller; And RF signal state detection system comprising a power amplifier module for amplifying the modulated transmission signal. The method of claim 8, And a third switch unit for branching the modulated transmission signal to the power amplifier and the power setting unit. The method of claim 8, And a fourth switch unit for selectively transmitting the transmission signal transmitted from the power amplification module or the power setting unit to the transmission antenna. The method of claim 1, It includes a phase synchronization circuit for sequentially changing the level of the oscillation frequency signal delivered to the interference signal measuring unit and the fine oscillation measuring unit, The interference signal measuring unit generates the data for analyzing the interference signal using the oscillation frequency signal, And the fine oscillation measuring unit generates data for analyzing the fine oscillation signal using the oscillation frequency signal. The method of claim 11, An Rx signal processor for demodulating the received signal and a Tx signal processor for modulating the transmitted signal; And a fifth switch unit connected to the phase synchronization circuit unit to branch the oscillation frequency signal to the interference signal measuring unit and the fine oscillation measuring unit or the Rx signal processing unit and the Tx signal processing unit. The method of claim 1, wherein the interference signal measuring unit A first mixer converting the received signal into an intermediate frequency signal; A first signal detecting unit detecting a power level of the intermediate frequency signal; And And a comparator configured to generate a data for analyzing the interference signal by comparing a sensed power level by applying a reference voltage. The method of claim 1, wherein the micro oscillation measuring unit A second mixer converting the received signal into an intermediate frequency signal in the fine oscillation signal region; And a second signal detector for generating the data for analyzing the micro oscillation signal by sensing the power level of the intermediate frequency signal in the micro oscillation signal region. The method of claim 1, wherein the power setting unit RF signal state detection system comprising a plurality of connected attenuators. The method according to any one of claims 1 to 15, The RF signal state detection system is an RF signal state detection system implemented on a mobile communication system. The method according to any one of claims 1 to 15, The RF signal state detection system is an RF signal state detection system implemented on an RFID system.

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