WO2010012130A1

WO2010012130A1 - System and method for controlling radio-frequency communication distance of mobile terminal

Info

Publication number: WO2010012130A1
Application number: PCT/CN2008/001837
Authority: WO
Inventors: 余运波
Original assignee: 深圳市中兴集成电路设计有限责任公司
Priority date: 2008-07-29
Filing date: 2008-11-03
Publication date: 2010-02-04
Also published as: CN101334470B; CN101334470A

Abstract

A system (10) and method are provided for controlling radio-frequency communication distance of mobile terminal. The method includes following steps: first, near-field profile corresponding to every kind of radio-frequency mobile terminal (12) is set up in the radio-frequency control terminal (13) by experiment; second, field strength of current radio-frequency mobile terminal (12) detected by detector array is matched with the near-field profile of the current radio-frequency mobile terminal (12) by a matching algorithm in order to obtain a matching degree used for comparing; at last, the obtained matching degree is compared with a preset threshold value corresponding to the type of the radio-frequency mobile terminal (13) for determining whether the distance between the current radio-frequency mobile terminal (12) and the radio-frequency control terminal (13) is in the set communication range, wherein the preset threshold value is preset in the radio-frequency control terminal (13).

Description

System and method for controlling radio frequency communication distance of mobile terminal

Field of the Invention This invention relates to record carriers for use with machines, and more particularly to record carriers with semiconductor circuit components, and more particularly to a system and method for controlling the radio frequency communication distance of a mobile terminal. Background technique

Radio frequency communication terminals (referred to as "mobile phones") have become very popular in real life. By adapting them to have close-range communication functions, the demand for functions such as mobile payment is becoming more and more intense. At present, the user identification module SIM card has appeared. The method of adding RF function (becoming RF SIM) or adding a short-range communication module on the mobile phone motherboard to realize close-range communication of the mobile phone, the appearance of this method makes the mobile phone become a super smart with recharge, consumption, transaction and identity authentication functions. The terminal greatly meets the urgent needs of the market.

Among them, the RF SIM-based mobile phone short-range communication solution has received extensive attention because of its simplicity and no need to change the mobile phone. In this solution, the RF SIM adopts UHF technology to enable the RF signal to be transmitted from the mobile phone, thereby eliminating the need for Transforming the phone will enable the phone to have close-range communication capabilities. However, because the shielding effect of different mobile phones is very different, the mobile terminal with poor shielding effect has a high transmission intensity of the radio frequency signal, and the communication distance can even reach about 1 meter. The mobile terminal with good shielding effect has a small transmission intensity of the radio frequency signal, which may cause Data cannot be sent and received normally, and it cannot be completed. Therefore, it is very difficult to accurately control the distance covered by the RF signal for various types of mobile terminals.

Many applications in real life, such as bus card swiping, impose strict requirements on the effective distance control of transactions. Excessive communication distance (such as above 10CM) will bring great security risks. Therefore, mobile phones are increasing near-field communication. At the same time, it must be able to effectively control the communication distance of its transactions.

The existing technology for controlling the distance of radio frequency communication so that it does not exceed the specified value is only passive sensing technology, such as the non-contact card technical specification specified in the IS014443 protocol and the RFID technical specification specified in ISO18000. These technologies are characterized by no card side. The source can only work by sensing the energy from the reader side coupling to achieve communication with the card reader. The RF SIM-based mobile phone short-range communication uses an active mode, and basically uses the UHF band, which makes it impossible to use passive technology to control the communication distance, because the UHF band RF signal has a strong wear. Through the ability, its distance control problem is more prominent.

In the prior art, the communication distance can be controlled by adjusting the radio frequency signal emission intensity of the mobile phone and the receiving sensitivity of the card reader, but this method is difficult to achieve reliable near due to various factors such as standing wave and signal reflection. Distance communication, in particular, cannot prevent malicious data communication attacks.

The above prior art method for controlling the radio frequency communication distance of a mobile terminal has the following disadvantages:

1. Radio frequency SIM-based mobile phone short-range communication uses an active mode, and basically uses the UHF band, and cannot use passive technology to control its communication distance;

2. The method of controlling the communication distance by adjusting the RF signal emission intensity of the mobile phone and the receiving sensitivity of the card reader is difficult to achieve reliable short-range communication due to various factors such as standing wave and signal reflection, especially if it cannot prevent malicious Data communication attack.

Studying the law of radio frequency signal transmission in the air, it can be found that the magnetic field characteristics and electric field characteristics of the radio frequency signal in the vicinity of the signal source are more obvious, while the electromagnetic field characteristics in the farther area are less obvious, which leads to the electromagnetic field in the vicinity of the signal source. There is no fixed law for the strong (hereinafter referred to as field strength) distribution. The actual observation and test also show that each mobile phone with short-range communication function has a close-range region (generally λ /2 π , where λ is the wavelength, which is called Near-field) RF field strength distribution is very uneven, which varies greatly with the type of mobile terminal. This RF near-field distribution is called near-field spectrum; and its near-field RF signal The field strength is distributed as a distribution, and the field strength distribution is independent of the type of RF communication terminal. Based on this finding, the present invention proposes a simple and low-cost solution, which can reliably control the data communication distance between the radio communication terminal and the radio frequency communication device in the near field range, thereby ensuring transaction security. It can even completely eliminate the threat of attacks such as remote malicious data communication. Summary of the invention

The technical problem to be solved by the present invention is to avoid a disadvantage of the above prior art and to propose a system and method for controlling the radio frequency communication distance of a mobile terminal.

The invention is a simple, low-cost and reliable solution to the problem of distance control of short-range communication of radio frequency communication terminals recently, and the method can not only reliably realize the distance control of data communication in the near field. Within the scope, and can fundamentally eliminate the threat of attacks such as remote malicious data communication.

The invention provides a system for controlling a radio frequency communication distance of a mobile terminal, in particular, a radio frequency mobile terminal and a radio frequency control terminal including a radio frequency SIM card;

The radio frequency control terminal receives the signal field strength of the radio frequency mobile terminal and detects the distribution of the signal field strength; the radio frequency control terminal determines whether the radio frequency mobile terminal is in the setting by performing mathematical analysis and calculation on the field strength distribution according to the specified requirements. Within the scope of communication.

The radio frequency control terminal includes a detector array and a host system, and each of the host system and the detector array The detector is connected to have the ability to acquire, calculate, and process the field strength value and its distribution law; the shape of each detector in the detector array includes a circle, a ring, a stick, an arc, a w, or a square; The detectors in the detector array can be made of ceramic, magnetic or copper materials.

The detector array is composed of N detectors that are 360°/N in geometrical position outside the RF control terminal, and is also detected by the N geometrically located 360°/N in the RF control terminal. The composition of the device, where N > 2 is a positive integer.

The host system is implemented by a single chip microcomputer system.

The present invention solves the technical problem, and can further implement the following technical solution, a method for controlling a radio frequency communication distance of a mobile terminal, based on a system for controlling a radio frequency communication distance of a mobile terminal, where the system includes a radio frequency SIM The radio frequency mobile terminal and the radio frequency control terminal of the card, the method comprising the steps of:

A. Establishing a corresponding near-field map for each type of radio frequency mobile terminal in the radio frequency control terminal by experiment;

B. Using the detector array to detect the signal field strength and its distribution of the current RF mobile terminal;

C. obtaining a matching degree for comparison by using a matching algorithm on the detected correlation between the signal field strength of the current radio frequency mobile terminal and its distribution and the near-field spectrum stored in the radio frequency control terminal;

D. Compare the matching degree obtained in step C with the correlation threshold value of the corresponding type of radio frequency mobile terminal preset in the radio frequency control terminal, so as to determine whether the distance between the current radio frequency mobile terminal and the radio frequency control terminal is within a specified range.

In step A, the near-field map reflects the correspondence between the distance τ of different types of radio frequency mobile terminals and the radio frequency control terminal and the signal field strength of each detector in the corresponding detector array. At this point, the field strength measurement values are arranged in a series, and the elements in the series are calculated to obtain the field strength field strength σ of the RF mobile terminal at the point when the distance from the RF control terminal is τ;

In the step Β, the field strength of the current radio frequency mobile terminal is also a set of series, and the elements in the sequence are tested for field strength values by detectors in the detector array.

In step C, the matching algorithm may be performing average calculation, variance calculation or a combination thereof. The elements in the series can be measured once in the test, or they can be taken after multiple measurements in the test.

In step D, the threshold value for comparison may be set in advance on the radio frequency control terminal according to actual conditions, or may be stored in the radio frequency mobile terminal, and the radio frequency control terminal is notified when establishing communication.

The near-field map and the elements of the field strength corresponding series of the current radio frequency mobile terminal are arranged in the same order. Compared with the prior art, the beneficial effects of the present invention are: 1. The solution of the invention is simple and easy to operate and low in cost;

2. The solution of the invention can reliably control the data communication distance between the radio frequency communication terminal and the radio frequency communication device in the near field range, ensure the security of the transaction, and even fundamentally eliminate the threat of attacks such as remote malicious data communication. DRAWINGS

Figure 1 is a schematic view showing the application of the system of the present invention;

2 is a schematic diagram of the composition of the radio frequency control terminal;

Figure 3 is a plot of field strength versus distance for a radio frequency mobile terminal;

Figure 4 is a diagram showing an example of a spectrum of a radio frequency mobile terminal at a distance from the radio frequency control terminal τ - !

Figure 5 shows the RF mobile terminal at a distance from the RF control terminal τ 0 whose field is stronger than σ. Diagram of the map;

Figure 6 shows the RF mobile terminal at the distance from the RF control terminal τ! On the distance, its field is stronger than σ! Diagram of the map;

FIG. 7 is a schematic diagram of a detector array distribution of a radio frequency control terminal. detailed description

The following is further described in detail in conjunction with the preferred embodiment shown in the drawings.

A system 10 for controlling the radio frequency communication distance of a mobile terminal, as shown in FIG. 1, includes a radio frequency mobile terminal 12 and a radio frequency control terminal 13 including a radio frequency SIM card 11;

The radio frequency control terminal 13 receives the signal field strength of the radio frequency mobile terminal 12 and detects the distribution of the signal field strength; the radio frequency control terminal 13 determines the radio frequency mobile terminal 12 by performing mathematical analysis and calculation on the field strength distribution according to the specified requirements. Whether it is within the set communication range.

The radio frequency control terminal 13 includes a detector array 131 and a host system 132. The host system 132 is electrically connected to the detectors of the detector array 131, and has the ability to acquire, calculate, and process field strength values and their distribution laws;

As shown in FIG. 2, the shape of each detector in the detector array 131 includes a circular shape, a circular shape, a stick shape, an arc shape, a W shape or a square shape; and the detectors in the detector array 131 can be made of ceramic or magnetic. Made of material or copper material. The detector array 131 is composed of N detectors 1311 that are 360°/N in geometrical position outside the radio frequency control terminal 13, and is also 360° in the geometrical position of the radio frequency control terminal 13 by 360°. The detector 13 of N consists of a positive integer with N > 2 here.

As shown in FIG. 2, in this embodiment, N=3, that is, three detectors are used, and the detector array 131 is composed of three 120-degree detectors 1311 outside the radio frequency control terminal 13 at the radio frequency control terminal 13. The interior is also composed of three detectors 1312 that are 120 degrees apart.

The host system 132 is implemented using a single chip system.

In order to solve the technical problem of the present invention, the technical solution may also be a method for controlling the radio frequency communication distance of the mobile terminal, based on a system 10 for controlling the radio frequency communication distance of the mobile terminal, the system including the radio frequency SIM card The RF mobile terminal 12 and the RF control terminal 13 of the 11th, in particular, include the steps of:

A. Establishing a corresponding near-field map for each type of radio frequency mobile terminal 12 in the RF control terminal 13 by experiment;

B. Using the detector array 131 to detect the signal field strength and its distribution of the current RF mobile terminal 12;

C. obtaining a matching degree for comparison by a matching algorithm on the detected degree of correlation between the signal field strength of the current radio frequency mobile terminal 12 and its distribution and the near-field spectrum stored in the radio frequency control terminal 13;

D. Comparing the matching degree obtained in step C with the correlation degree threshold value of the corresponding type radio frequency mobile terminal 12 preset in the radio frequency control terminal 13, thereby determining whether the distance between the current radio frequency mobile terminal 12 and the radio frequency control terminal 13 is Within the prescribed range.

In step A, the near-field map reflects the correspondence between the distance τ of different types of radio frequency mobile terminals 12 and the radio frequency control terminal 13 and the signal field strength of each detector in the corresponding detector array. The field strength measurement value of the detector is arranged in a sequence at the point, and the elements of the series are calculated to obtain the field strength field strength σ of the RF mobile terminal 12 at the point when the distance from the RF control terminal 13 is τ;

In the step, the field strength of the current radio frequency mobile terminal 12 is also a set of series, and the elements in the sequence are the field strength values of the detectors in the detector array 131.

In step C, the matching algorithm may be performing average calculation, variance calculation or a combination thereof. The elements in the series can be measured once in the test, or they can be averaged after multiple measurements in the test.

In step D, the threshold value for comparison may be preset on the radio frequency control terminal according to actual conditions. The setting may also be stored in the radio frequency mobile terminal 12, and the radio frequency control terminal 13 is informed when the communication is established. The near-field map and the elements of the field strength corresponding sequence of the current radio frequency mobile terminal 12 are arranged in the same order.

401 represents the position projection range of the radio frequency mobile terminal 12 when communicating with the radio frequency control terminal 13, and the area represented by 501 in FIGS. 4 and 7 is the radio frequency mobile terminal 12 at the distance from the radio frequency control terminal 13 as τ -! When the field is stronger than the map distribution of σ, the area represented by 502 in FIGS. 5 and 7 is the radio frequency mobile terminal 12 at the distance from the radio frequency control terminal 13 being τ. When the field is stronger than the map distribution of σ ₀ , the area represented by 503 in FIGS. 6 and 7 is the radio frequency mobile terminal 12 at the distance from the radio frequency control terminal 13 is τ! When the field is stronger than σ, the distribution of the spectrum.

As shown in FIG. 7, when the test is performed, the approximate position of the required RF mobile terminal 12 in communication is first set in the detector array 131. As shown by reference numeral 401 in FIG. The 120-degree detector array 1312 and the outer three 120-degree detector arrays 1311, wherein the internal detector array is less than τ - ! from the center of the RF mobile terminal 12, and the external detector array is separated from the RF The average distance of the center of the mobile terminal 12 is greater than _{τ ι} .

The foregoing implementation process is a preferred implementation process of the present invention. Generally, variations and substitutions made by those skilled in the art based on the present invention are included in the scope of the present invention. For example, the present invention may also adopt an indicator similar to the field strength. Instead, each detector is connected to the RF receiving device, and the same effect can be obtained by using the error rate of the received RF signal or the communication success rate.

Claims

Rights request

A system (10) for controlling a radio communication distance of a mobile terminal, comprising: a radio frequency SIM card included

(11) an RF mobile terminal (12) and a radio frequency control terminal (13);

The radio frequency control terminal (13) receives the signal field strength of the radio frequency mobile terminal (12) and detects the distribution of the signal field strength; the radio frequency control terminal (13) performs mathematical analysis and calculation on the field strength distribution according to the specified requirements, thereby It is judged whether the radio frequency mobile terminal (12) is within the set communication range.

2. The system for controlling a radio frequency communication distance of a mobile terminal according to claim 1, wherein:

The radio frequency control terminal (13) includes a detector array (131) and a host system (132), and the host system (132) is connected to each detector of the detector array (131), and has a field strength value and a distribution rule thereof. Acquisition, calculation and processing capabilities;

The shape of each detector in the detector array (131) includes a circular shape, a circular shape, a stick shape, an arc shape, a W shape or a square shape; each detector in the detector array (131) may be made of ceramic, magnetic material or copper. Made of a material.

3. The system for controlling a radio frequency communication distance of a mobile terminal according to claim 1, wherein:

The detector array (131) is composed of N detectors (1311) that are 360°/N in geometrical position outside the radio frequency control terminal (13), and N in the radio frequency control terminal (13). The geometrical position consists of a detector (1312) that is 360°/N from each other, where N>2 is a positive integer.

4. The system for controlling a radio frequency communication distance of a mobile terminal according to claim 1, wherein:

The host system (132) is implemented by a single chip microcomputer system.

5. A method for controlling a radio frequency communication distance of a mobile terminal, based on a system for controlling a radio frequency communication distance of a mobile terminal

(10) The system includes a radio frequency mobile terminal (12) and a radio frequency control terminal (13) including a radio frequency SIM card (11), and the method includes the following steps:

E. Establish a corresponding near-field map for each type of RF mobile terminal (12) in the RF control terminal (13) by experiment;

F. detecting the signal field strength and its distribution of the current RF mobile terminal (12) by using the detector array (131);

G. obtaining a correlation between the detected signal field strength of the current radio frequency mobile terminal (12) and its distribution and the near-field spectrum stored in the radio frequency control terminal (13), by a matching algorithm for comparison suitability;

H. The matching degree obtained in step C and the corresponding type of radio frequency preset in the radio frequency control terminal (13) The correlation threshold of the mobile terminal (12) is compared to determine whether the distance between the current radio mobile terminal (12) and the radio frequency control terminal (13) is within a specified range.

The method for controlling a radio frequency communication distance of a mobile terminal according to claim 5, wherein:

In step A, the near-field map reflects the correspondence between the distance τ of different types of radio frequency mobile terminals (12) and the radio frequency control terminal (13) and the signal field strength of each detector in the corresponding detector array. Relationship, the field strength measurement values of the detectors are arranged in a sequence, and each element in the series is calculated to obtain a field at the point where the radio frequency mobile terminal (12) is τ from the radio frequency control terminal (13) Strong field strength σ ;

In step Β, the field strength of the current radio frequency mobile terminal (12) is also a set of series, and the elements in the sequence are tested for field strength values by detectors in the detector array (131).

In step C, the matching algorithm may be performing an average calculation, a variance calculation, or a combination thereof.

The method for controlling a radio frequency communication distance of a mobile terminal according to claim 5 or 6, wherein:

The elements in the series can be measured once in the test, or they can be averaged after multiple measurements in the test.

The method for controlling a radio frequency communication distance of a mobile terminal according to claim 5 or 7, wherein:

In step D, the threshold value for comparison may be set in advance on the radio frequency control terminal (13) according to actual conditions, or may be stored in the radio frequency mobile terminal (12), and the radio frequency control terminal is notified when establishing communication. (13).

0. The method for controlling a radio frequency communication distance of a mobile terminal according to claim 6, wherein:

The near-field map and the elements of the field strength corresponding sequence of the current radio frequency mobile terminal (12) are arranged in the same order.