CN109348420B

CN109348420B - Method and system for identifying distance between wireless devices

Info

Publication number: CN109348420B
Application number: CN201811441475.9A
Authority: CN
Inventors: 丁昊; 潘进; 齐芸芸
Original assignee: Wuhan Weizhi Chuangda Technology Co ltd
Current assignee: Wuhan Weizhi Chuangda Technology Co ltd
Priority date: 2018-11-28
Filing date: 2018-11-28
Publication date: 2021-01-29
Anticipated expiration: 2038-11-28
Also published as: CN109348420A

Abstract

The invention discloses a method and a system for identifying distance between wireless devices. The method comprises the following steps: receiving a first wireless signal group sent by any signal source for n times, wherein the first wireless signal group comprises m first wireless signals with different powers, n is a positive integer greater than or equal to 1, and m is a positive integer greater than or equal to 2; evaluating a signal quality of the first wireless signal; and determining the distance of the signal source or the range of the distance according to the signal quality of the n x m first wireless signals. The invention realizes the distance identification between wireless devices with low power consumption and low cost by evaluating the signal quality of a plurality of groups of wireless signals with different powers.

Description

Method and system for identifying distance between wireless devices

Technical Field

The present invention relates to the field of wireless communication technologies, and in particular, to a method and a system for identifying a distance between wireless devices.

Background

Since the RSSI and the distance of the signal strength between the wireless devices are not linear, the RSSI fluctuates greatly during the wireless communication process under the influence of interference, reflection, refraction and other factors on the first wireless signal, and the distance between the wireless devices cannot be identified effectively.

Disclosure of Invention

The embodiment of the invention at least discloses a method for identifying the distance between wireless devices, which can solve the problems of high positioning power consumption and high cost of the wireless devices.

The method comprises the following steps:

receiving a first wireless signal group sent by any signal source for n times, wherein the first wireless signal group comprises m first wireless signals with different powers, n is a positive integer greater than or equal to 1, and m is a positive integer greater than or equal to 2;

acquiring the signal strength of the first wireless signal;

comparing the signal intensity with a preset threshold intensity and generating an evaluation value;

and determining the distance of the signal source or the range of the distance according to the evaluation values of the n x m first wireless signals.

In some embodiments of the present disclosure, comparing the signal strength to the threshold strength is configured to:

the threshold strength comprises an upper limit strength and a lower limit strength, the upper limit strength and the lower limit strength divide the value range of the signal strength into an upper limit range, a middle range and a lower limit range, and the value of the signal strength is judged to be in the upper limit range, the middle range or the lower limit range; generating the evaluation value configured to:

and generating the evaluation value according to the value of the signal intensity in the upper limit interval, the middle interval or the lower limit interval.

In some embodiments of the present disclosure, the upper strength limit and/or the lower strength limit are adjusted based on a signal gain or a signal attenuation resulting from receiving the first set of wireless signals.

In some embodiments of the present disclosure, determining a distance or a range of distances from the signal source according to the evaluation values of the n × m first wireless signals is configured to:

accumulating evaluation values of n first wireless signals with the same power into a statistic value;

and judging the distance or the range of the distance of the signal source according to the statistical values of the m first wireless signals with different powers.

In some embodiments of the present disclosure, the determining, according to the statistical values of m different powers of the first wireless signal, a distance or a range of distances of the signal source is configured to:

respectively judging the quality grades of the m first wireless signals with different powers according to the statistical values;

and judging the distance of the signal source or the range of the distance according to the quality grades of the m first wireless signals with different powers.

In some embodiments disclosed in the present specification, m-3,

the first wireless signal group comprises first wireless signals with low power, middle power and high power,

the values of the small power, the middle power and the large power are determined by the acquired nominal power;

obtaining the nominal power is configured to:

setting a reference distance taking the signal source as an end point or a starting point;

receiving a standard wireless signal from a maximum power to a minimum power transmitted by a signal source;

and recording the current power of the standard wireless signal as the nominal power after the received signal strength of the standard wireless signal is between the upper limit strength and the lower limit strength.

In some embodiments of the present disclosure, the method comprises:

and classifying the corresponding colors of the distance or the distance range of the signal source according to the approaching distance identification mechanism or the departing distance identification mechanism.

In some embodiments of the present disclosure, the close distance identification mechanism or the far distance identification mechanism is configured to,

dividing the signal source into at least one inner interval in the reference distance and at least one outer interval outside the reference distance;

classifying the inner interval and the outer interval by different colors;

matching the distance of the signal source or the range of the distance according to the color of the internal interval or the external interval;

and determining that the signal source is in a close state or a far state according to the distance of the signal source or the color matched with the distance range.

In some embodiments of the present disclosure, the method comprises:

transmitting n times a second set of wireless signals identical to the first set of wireless signals to the signal source, the second set of wireless signals including m second wireless signals corresponding to the first wireless signals, the second wireless signals for being received by the signal source and evaluating signal strength;

receiving the signal intensity of the second wireless signal returned after the signal source evaluation;

and determining the distance of the signal source or the range of the distance according to the signal intensity of the n x m first wireless signals and the signal intensity of the n x m second wireless signals.

In some embodiments of the present disclosure, the method comprises:

any two of the m first wireless signals with different powers are configured to serve as a secondary up signal and a secondary down signal, and at least one secondary middle signal is randomly selected between the powers of the secondary up signal and the secondary down signal;

receiving the signal source and sending a secondary wireless signal group, wherein the secondary wireless signal group comprises the secondary up signal, at least one secondary middle signal and the secondary down signal;

evaluating signal strength of the set of secondary wireless signals;

determining the distance or the distance range from the signal strength of the set of secondary wireless signals.

The embodiment of the invention at least discloses a distance identification system between wireless devices.

The system comprises a first distance identification device and a second distance identification device;

the first distance identification device and the second distance identification device mutually transmit n times of wireless signal groups, each wireless signal group comprises m wireless signals with different powers, n is a positive integer greater than or equal to 1, and m is a positive integer greater than or equal to 2;

the first distance recognition device and the second distance recognition device respectively acquire the signal intensity of the wireless signal, compare the signal intensity with a preset threshold intensity and generate an evaluation value;

the first distance recognition device and/or the second distance recognition device determine a distance or a distance range between the first distance recognition device and the second distance recognition device according to the evaluation values of the 2 x n x m wireless signals.

In some embodiments of the present disclosure, the first distance identification device and/or the second distance identification device is configured with a distance display module;

the distance display module displays the distance or the distance range between the first distance identification device and the second distance identification device according to the color of the approaching distance identification mechanism or the departing distance identification mechanism.

In view of the above, other features and advantages of the disclosed exemplary embodiments will become apparent from the following detailed description of the disclosed exemplary embodiments, which proceeds with reference to the accompanying drawings.

Drawings

In order to more clearly illustrate the solution of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and that for a person skilled in the art, other related drawings can be obtained from these drawings without inventive effort.

FIG. 1 is a system diagram of a wireless device A and a wireless device B according to an embodiment;

FIG. 2 is a flow chart of the second embodiment;

FIG. 3 is a flowchart of the third embodiment.

Detailed Description

To make the objects, aspects and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described more clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is to be understood that the described embodiments are some, but not all embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, as disclosed in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

The embodiment discloses a distance identification method between wireless devices; the method of the embodiment can realize distance identification between the wireless device A and the wireless device B with low power consumption and low cost.

To achieve the above, please refer to fig. 1. The wireless device a and the wireless device B of the embodiment include an STM32F103R8 processor, a wireless communication module SX1278, a wireless communication antenna, an electric energy power supply module, and a distance display module. The STM32F103R8 processor is used for processing and operation, has a sleep function, can automatically enter a sleep state with low power consumption, and then performs sleep wake-up according to an internal clock timer. The wireless communication module SX1278 and the wireless communication antenna are used for sending and receiving wireless signals, the minimum transmitting power of the wireless communication module SX1278 is-4 dBm, and the maximum transmitting power of the wireless communication module SX1278 is +17 dBm. And the distance display module is used for displaying different colors according to the distance after the wireless device A and the wireless device B realize distance identification.

Through the scheme, the wireless device a and the wireless device B can mutually transmit and receive three wireless signals with different powers, namely, a low-power PMIN, a medium-power PMID and a high-power PMAX.

The values of the small power PMIN, the middle power PMID and the large power PMAX are mainly determined by the coverage range of the wireless signal; for example, the coverage of the wireless signal of the low-power PMIN is relatively close, the coverage of the wireless signal of the high-power PMAX is relatively far, and the coverage of the wireless signal of the intermediate-power PMID is moderate.

The wireless device B receives n times of wireless signal groups sent by the wireless device A, wherein the wireless signal groups comprise three wireless signals of low-power PMIN, intermediate-power PMID and high-power PMAX; n is a positive integer greater than or equal to 1, and for illustrative purposes, n is 5.

In some embodiments, the number of wireless signal transmissions is increased from 5 to 3 x 5 when the signal strength RSSI of the wireless signal fluctuates by more than +/-15 dBm; and then removing 2 x 5 signal strength RSSIs with overlarge fluctuation according to a normal distribution principle, and performing distance identification by using the remaining 5 signal strength RSSIs.

After receiving the wireless signal group 5 times, the wireless device evaluates the signal quality of each of the three wireless signals, and confirms the distance between the wireless device a and the wireless device B. In this embodiment, the wireless device B evaluates the wireless signal of the low-power PMIN as an example:

the wireless device B receives a wireless signal of the low-power PMIN sent by the wireless device A and then acquires the corresponding signal strength RSSI _ R of the wireless signal; and comparing the acquired signal strength with the previously defined UPPER limit signal strength RSSI _ UPPER and LOWER limit signal strength RSSI _ LOWER respectively to acquire the evaluation value of the wireless signal.

In some embodiments, the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER may be dynamically adjusted according to the application scenarios of the wireless device a and the wireless device B; initially setting the UPPER limit signal strength RSSI _ UPPER to-65 dBm by default, and setting the LOWER limit signal strength RSSI _ LOWER to-85 dBm; the difference between the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER is set to 20dBm by default.

The signal strength RSSI _ R is greater than or equal to the UPPER limit signal strength RSSI _ UPPER, and the evaluation value of the wireless signal is + 2; the signal strength RSSI _ R is smaller than the UPPER limit signal strength RSSI _ UPPER and larger than the LOWER limit signal strength RSSI _ LOWER, and the evaluation value of the wireless signal is + 1; the signal strength RSSI _ R is less than or equal to the LOWER limit signal strength RSSI _ LOWER, and the evaluation value of the wireless signal is 0.

The wireless device B accumulates evaluation values corresponding to wireless signals of 5 small-power PMINs, and obtains a statistic PMIN _ RC _ AB of signal strength.

Similar to the above scheme, after receiving the wireless signal of the intermediate power PMID and the high-power PMAX sent by the wireless device a, the wireless device B obtains the statistical value PMID _ RC _ AB corresponding to the wireless signal of the intermediate power PMID and the statistical value PMAX _ RC _ AB corresponding to the wireless signal of the high-power PMAX.

Similar to the above scheme, after the wireless device a receives the wireless signals of the low power PMIN, the intermediate power PMID and the high power MAX sent by the wireless device B5 times, the statistical value PMIN _ RC _ BA, the statistical value PMID _ RC _ BA and the statistical value PMAX _ RC _ BA are obtained.

The wireless device A and the wireless device B exchange the statistical values of the three wireless signals and then accumulate the statistical values, and the wireless device A and the wireless device B respectively acquire the statistical values PMIN _ RC, PMID _ RC and PMAX _ RC of the three wireless signals.

PMIN_RC＝PMIN_RC_AB+PMIN_RC_BA；

PMID_RC＝PMID_RC_AB+PMID_RC_BA；

PMAX_RC＝PMAX_RC_AB+PMAX_RC_BA。

The wireless device A or the wireless device B respectively obtains the reliability levels of wireless signals of the small power PMIN, the intermediate power PMID and the large power PMAX according to the statistic PMIN _ RC, the statistic PMID _ RC and the statistic PMAX _ RC;

in this embodiment, the example of obtaining the corresponding reliability level of the wireless signal of the low-power PMIN according to the statistical value PMIN _ RC is as follows:

the general judgment principle is to judge whether the statistical value PMIN _ RC is larger than Kxn multiplied by 0.9 or smaller than Kxn multiplied by 0.1; where K is an evaluation value of the wireless signal when the corresponding signal strength RSSI _ R of the low-power PMIN is greater than or equal to the UPPER limit signal strength RSSI _ UPPER, and n is a number of times that the wireless device a or the wireless device B receives the wireless signal group.

PMIN _ RC is larger than Kxn0.9, which means that more than 90% of normal communication can be ensured through wireless signals of low-power PMIN between the wireless device A and the wireless device B; the quality grade corresponding to the low-power PMIN is excellent, i.e. the reliable grade PMIN _ RL is equal to Y.

PMIN _ RC is smaller than Kxn0.1, which means that wireless signal communication between the wireless device A and the wireless device B through low-power PMIN is achieved, and normal communication is not more than 10%; the quality grade corresponding to the low-power PMIN is poor, i.e. the reliable grade PMIN _ RL is X.

PMIN _ RC is less than or equal to K × n × 0.9 and PMIN _ RC is greater than or equal to K × n × 0.1, which indicates that normal communication is unstable through wireless signal communication between the wireless device a and the wireless device B through the low-power PMIN; the quality grade corresponding to the low-power PMIN is abnormal, i.e. the reliable grade PMIN _ RL ═ Z.

Similar to the above scheme, a reliability level PMID _ RL of the intermediate power PMID and a reliability level PMAX _ RL of the high power PMAX are obtained.

After wireless device a or wireless device B obtains reliability level PMIN _ RL, reliability level PMID _ RL, and reliability level PMAX _ RL, it is determined that the distance between wireless device a and wireless device B is in the distance level and distance state, as follows.

In the table:

PMIN _ RL Y, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is L1 level, indicating that two wireless devices are close and the distance status is close.

PMIN _ RL Z, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is level L2, indicating that two wireless devices are at the threshold of minimum power communication and the distance state is near the threshold.

PMIN _ RL X, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is L3, indicating that the two wireless devices are outside minimum power communication, within intermediate power communication, and within intermediate distance.

PMIN _ RL-X, PMID _ RL-Z and PMAX _ RL-Y; the distance level is level L4, indicating that two wireless devices are at an intermediate power communication threshold and the distance state is at an intermediate threshold.

PMIN _ RL _ X and PMAX _ RL _ Y are X, PMID _ RL ═ X; the distance level is L5 level, which indicates that two wireless devices are outside the middle power communication and inside the high power communication, and the distance state is defined as outside the middle;

PMIN _ RL-X, PMID _ RL-X and PMAX _ RL-Z; the distance level is L6 level, which indicates that two wireless devices are at the critical point of high-power communication, and the distance state is far from the critical point;

PMIN _ RL X, PMID _ RL ═ X and PMAX _ RL ═ X; the distance level is L7, which indicates that the two wireless devices are out of high power communication and the distance status is far away.

By combining the above solutions, the wireless device a and the wireless device B obtain the distance status only by three wireless signals with different powers transmitted multiple times, and directly determine the distance range of the wireless device a and the wireless device B without using time service and synchronization of high-precision clock signals.

Further, the wireless device a and/or the wireless device B of the present embodiment are configured with a close distance identification mechanism and a far distance identification mechanism.

The approach distance recognition mechanism recognizes whether the distance between the wireless device a and the wireless device B is within a given reference distance RD, and the closer the distance between the wireless device a and the wireless device B is, the better; in this embodiment, the 7 distance levels are color-classified according to the coverage of the reference distance RD, which is specifically shown in the following table:

in the table:

the color classification at L1 is green, indicating that wireless device a and wireless device B are close together and within the communication range of the wireless signal of the low-power PMIN;

color classification as yellow at distance levels L2 and L3, indicating that wireless device a and wireless device B are within wireless communication range of the wireless signal of the intermediate power PMID;

the wireless device a and the wireless device B are classified into red color when the distance levels are L4, L5 and L6, the distance between the wireless device a and the wireless device B is out of the wireless communication range of the wireless signal of the intermediate power PMID, and the wireless device a and the wireless device B can perform wireless communication by using the wireless signal of the maximum power PMAX;

the color classification at L7 is black, indicating that the distance between wireless device a and wireless device B is beyond the wireless communication range of the wireless signal of high-power PMAX.

Preferably, when only three colors, i.e., green, yellow, and red, can be classified in the approach distance recognition mechanism, black can be classified as red.

The distance identification mechanism identifies whether the distance between the wireless device a and the wireless device B exceeds a given reference distance RD, and the farther the distance between the wireless device a and the wireless device B is, the better the distance is; in this embodiment, the 7 distance levels are color-classified according to the coverage of the reference distance RD, which is specifically shown in the following table:

in the table:

the color classification at distance levels L1 and L2 is red, indicating that wireless device a and wireless device B are close, and do not exceed the wireless communication range of the wireless signal of the low-power PMIN;

the color classification at the distance levels L3 and L4 is yellow, indicating that the distance of wireless device a and wireless device B exceeds the wireless communication range of the wireless signal of the low power PMIN, but does not exceed the wireless communication range of the intermediate power PMID;

the color classification is green when the distance levels are L5 and L6, which indicates that the distance between the wireless device A and the wireless device B exceeds the wireless communication range of the wireless signal of the intermediate power PMID but does not exceed the wireless communication range of the high-power PMAX;

the color classification at the distance level of L7 is a communication failure, indicating that the distance between wireless device a and wireless device B is beyond the wireless communication range of the wireless signal of high-power PMAX.

With the above configuration, when the wireless device a and/or the wireless device B according to the present embodiment are mounted on a terminal having a display function, the distance ranges of the wireless device a and the wireless device B in the approach distance recognition mechanism or the separation distance recognition mechanism can be determined based on the color displayed on the terminal.

In some embodiments, values of the small power PMIN, the intermediate power PMID, and the large power PMAX close to the distance identification mechanism and far from the distance identification mechanism are determined according to a nominal power PSTD, which is set as follows.

The distance between the wireless device a and the wireless device B is configured as a reference distance RD;

wireless device a and wireless device B transmit wireless signals to each other at the maximum transmission power of the wireless transmitter and adjust the power of the transmitted wireless signals in stepwise decreases;

the wireless device A and the wireless device B respectively receive the signal strength RSSI _ R of the wireless signal and judge whether the signal strength RSSI _ R is between the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOW;

the wireless device A and the wireless device B adjust to proper wireless transmission power PSend until the signal strength RSSI _ R of the wireless signals received by the wireless device A and the wireless device B is between the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER;

the appropriate radio transmission power PSend is recorded as the nominal power PSTD of the reference distance RD.

In the approach distance identification mechanism, values of the small power PMIN, the intermediate power PMID and the large power PMAX are values taking the nominal power PSTD as the intermediate power PMID; taking the minimum transmitting power of the wireless transmitter as a value of the small-power PMIN; taking the nominal power PSTD +9dBm as the value of the high-power PMAX;

in the remote distance identification mechanism, values of the small power PMIN, the intermediate power PMID and the large power PMAX are values taking the nominal power PSTD as the intermediate power PMID; taking the maximum transmitting power of the wireless transmitter as a value of the high-power PMAX; and taking the nominal power PSTD-9 dBm as the value of the small-power PMIN.

In some embodiments, the UPPER and LOWER signal strengths RSSI _ UPPER and RSSI _ LOWER can be adjusted according to different signal gains or attenuations of different wireless transmitters and wireless receivers, as follows.

In the approach distance identification mechanism, when a wireless signal received by a wireless communication module has stronger signal gain and/or PMID is less than PMIN +3dBm, the values of the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER are increased by 5 dBm/time until PMID is more than or equal to PMIN +3 dBm.

In the approach distance identification mechanism, when a wireless communication module receives a wireless signal and has stronger signal gain, the initial configuration UPPER limit signal strength RSSI _ UPPER is set to-55 dBm, and the LOWER limit signal strength RSSI _ LOWER is-65 dBm.

In the remote distance identification mechanism, when the wireless communication module receives a wireless signal and has stronger signal attenuation and/or PMID is larger than PMAX-3 dBm, the values of the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER are reduced by 5 dBm/time until PMID is less than or equal to PMIN-3 dBm.

In the remote distance identification mechanism, when the wireless communication module receives a wireless signal and has stronger signal attenuation, the initial configuration UPPER limit signal strength RSSI _ UPPER is set to-85 dBm, and the limit signal strength RSSI _ LOWER is set to-95 dBm.

When the consistency of the signal strength RSSI _ R of the wireless signals received by the wireless communication module is good in the approaching distance identification mechanism or the departing distance identification mechanism, the difference value between the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER is adjusted to be 10 dBm.

In the server at the wireless communication remote end of the wireless device a and/or the wireless device B of the embodiment, the wireless device a and/or the wireless device B uploads all data generated in each distance identification; the server controls the wireless device A and/or the wireless device B to adjust values of the small power PMIN, the middle power PMID, the large power PMAX, the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER according to all the acquired data.

In some embodiments, after the distance between the wireless device a and/or the wireless device B is divided into 7 levels, the secondary distance identification is selected for the wireless device a and the wireless device B to improve the identification accuracy of the distance between the wireless device a and the wireless device B.

Determining the distance grade between the wireless device A and the wireless device B, and receiving and transmitting the new wireless signals of the small power PMIN2, the intermediate power PMID2 and the high power PMAX2 according to the distance grade. The embodiment secondarily identifies the distance between the wireless device a and the wireless device B according to the wireless signals of the low-power PMIN2, the intermediate-power PMID2 and the high-power PMAX 2.

When the distance between the wireless device a and the wireless device B is ranked at L1 or L2 or L3, the small power PMIN2 is configured as PMIN, the intermediate power PMID2 is configured as PMID- (PMID-PMIN)/2, and the large power PMAX2 is configured as PMID.

When the distance between the wireless device a and the wireless device B is ranked at L5 or L6 or L7, a small power PMIN2 ═ PMID, an intermediate power PMID2 ═ PMID + (PMAX-PMID)/2, and a large power PMAX2 ═ PMAX are configured.

When the distance grade between the wireless device A and the wireless device B is L4, judging that the distance between the wireless device A and the wireless device B is approximate to a reference distance RD; the configuration is small power PMIN2 ═ PMID- (PMID-PMIN)/2, high power PMID2 ═ PMID, and high power PMAX2 ═ PMID + (PMAX-PMID)/2.

In some embodiments, the RSSI signal quality-distance approximate conversion table is stored in the wireless device a and/or the wireless device B, and the wireless device a and/or the wireless device B searches the approximate distances between the wireless device a and the wireless device B according to the average value RvPMIN, the average value RvPMID and the average value RvPMAX of the RSSI of the signal strengths of three different transmission powers in the RSSI signal quality-distance approximate conversion table, so as to correct the identified distance between the wireless device a and the wireless device B.

Example two

Referring to fig. 2, the present embodiment discloses a method for identifying a distance between wireless devices; the method of the embodiment can realize the distance identification of the wireless device B and the signal source.

The signal source sends a wireless signal group to the wireless device B, and the wireless signal group comprises three wireless signals with different powers, namely a low-power PMIN, a middle-power PMID and a high-power PMAX.

The wireless device B receives a wireless signal group for 5 times sent by a signal source, wherein the wireless signal group comprises three wireless signals of low power PMIN, intermediate power PMID and high power PMAX.

After receiving the wireless signal group 5 times, the wireless device evaluates the signal quality of each of the three wireless signals, and confirms the distance between the signal source and the wireless device B. In this embodiment, the wireless device B evaluates the wireless signal of the low-power PMIN as an example:

the wireless device B receives a wireless signal of a small-power PMIN sent by a signal source and then acquires the corresponding signal strength RSSI _ R of the wireless signal; and comparing the acquired signal strength with the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER to acquire an evaluation value of the wireless signal.

The wireless device B accumulates evaluation values corresponding to wireless signals of 5 small-power PMINs, and obtains a statistic PMIN _ RC of signal strength.

The wireless device B obtains the statistical value PMID _ RC corresponding to the wireless signal of the intermediate power PMID and the statistical value PMAX _ RC corresponding to the wireless signal of the high-power PMAX after receiving the wireless signal of the intermediate power PMID and the wireless signal of the high-power PMAX sent by the signal source.

And the wireless device B respectively acquires the reliability levels of the wireless signals of the low-power PMIN, the intermediate-power PMID and the high-power PMAX according to the statistic PMIN _ RC, the statistic PMID _ RC and the statistic PMAX _ RC.

the PMIN _ RC is judged to be larger than 2 multiplied by 5 multiplied by 0.9, which indicates that more than 90% of normal communication can be ensured through a wireless signal of low-power PMIN between the signal source and the wireless device B; the quality grade corresponding to the low-power PMIN is excellent, i.e. the reliable grade PMIN _ RL is equal to Y.

Judging that PMIN _ RC is smaller than 2 multiplied by 5 multiplied by 0.1, which indicates that the signal source and the wireless device B communicate through the wireless signal of low-power PMIN, and the normal communication is not more than 10%; the quality grade corresponding to the low-power PMIN is poor, i.e. the reliable grade PMIN _ RL is X.

Determining that PMIN _ RC is less than or equal to 2 × 5 × 0.9 and PMIN _ RC is greater than or equal to 2 × 5 × 0.1, which indicates that normal communication is unstable through wireless signal communication of low-power PMIN between the signal source and the wireless device B; the quality grade corresponding to the low-power PMIN is abnormal, i.e. the reliable grade PMIN _ RL ═ Z.

After the wireless device B obtains the reliability level PMIN _ RL, the reliability level PMID _ RL and the reliability level PMAX _ RL, the distance status between the signal source and the wireless device B is determined as follows.

PMIN _ RL Y, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is L1 level, which indicates that the wireless device B and the signal source are close to each other, and the distance state is close;

PMIN _ RL Z, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is L2 level, which indicates that the wireless device B and the signal source are at the critical point of minimum power communication, and the distance state is close to the critical point;

PMIN _ RL X, PMID _ RL _ Y and PMAX _ RL _ Y; the distance level is L3 level, which indicates that the wireless device B and the signal source are outside the minimum power communication, within the intermediate power communication, and the distance state is within the intermediate;

PMIN _ RL-X, PMID _ RL-Z and PMAX _ RL-Y; the distance level is L4 level, which indicates that the wireless device B and the signal source are at the intermediate power communication critical point, and the distance state is the intermediate critical point;

PMIN _ RL _ X and PMAX _ RL _ Y are X, PMID _ RL ═ X; the distance level is L5 level, which indicates that the wireless device B and the signal source are outside the middle power communication and within the high power communication, and defines the distance state as outside the middle;

PMIN _ RL-X, PMID _ RL-X and PMAX _ RL-Z; the distance level is L6 level, which indicates that the wireless device B and the signal source are at the high-power communication critical position, and the distance state is far from the critical position;

PMIN _ RL X, PMID _ RL ═ X and PMAX _ RL ═ X; the distance level is L7 level, which indicates that the wireless device B and the signal source are out of high-power communication and the distance state is far away.

EXAMPLE III

Referring to fig. 3, in the present embodiment, the signal source of the second embodiment is replaced by a wireless device a capable of transmitting and receiving wireless signals.

The wireless device a of the present embodiment transmits a wireless signal group to the wireless device B as follows.

The wireless device B receives the wireless signal group for 5 times sent by the wireless device A, and the wireless signal group comprises three wireless signals of low power PMIN, intermediate power PMID and high power PMAX.

The wireless device B obtains the statistical value PMID _ RC _ AB corresponding to the wireless signal of the intermediate power PMID and the statistical value PMAX _ RC _ AB corresponding to the wireless signal of the high-power PMAX after receiving the wireless signal of the intermediate power PMID and the wireless signal of the high-power PMAX sent by the signal source.

The wireless device B of the present embodiment transmits a wireless signal group to the wireless device a as follows.

The wireless device A receives the wireless signal group for 5 times sent by the wireless device B, and the wireless signal group comprises three wireless signals of low power PMIN, intermediate power PMID and high power PMAX.

After receiving the wireless signal group 5 times, the wireless device a evaluates the signal quality of each of the three wireless signals, and confirms the distance between the signal source and the wireless device B. In this embodiment, the wireless device B evaluates the wireless signal of the low-power PMIN as an example:

the wireless device A receives a wireless signal of a small-power PMIN sent by a signal source and then acquires the corresponding signal strength RSSI _ R of the wireless signal; and comparing the acquired signal strength with the UPPER limit signal strength RSSI _ UPPER and the LOWER limit signal strength RSSI _ LOWER to acquire an evaluation value of the wireless signal.

The wireless device A accumulates evaluation values corresponding to wireless signals of 5 small-power PMINs, and obtains a statistic PMIN _ RC _ BA of signal strength.

The wireless device a obtains the statistical value PMID _ RC _ BA corresponding to the wireless signal of the intermediate power PMID and the statistical value PMAX _ RC _ BA corresponding to the wireless signal of the high-power PMAX after receiving the wireless signal of the intermediate power PMID and the wireless signal of the high-power PMAX sent by the signal source.

And the wireless device A and/or the wireless device B acquires the reliability levels of wireless signals of low-power PMIN, intermediate-power PMID and high-power PMAX according to PMIN _ RC _ AB, PMID _ RC _ AB, PMAX _ RC _ AB, PMIN _ RC _ BA, PMID _ RC _ BA and PMAX _ RC _ BA.

Wireless device a and/or wireless device B may determine a range class and a range status between wireless device a and wireless device B based on the reliability level of the wireless signals of low power PMIN, medium power PMID, and high power PMAX.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for distance identification between wireless devices, the method comprising:

acquiring the signal strength of the first wireless signal;

2. The inter-wireless-device distance identification method of claim 1, wherein comparing the signal strength to the threshold strength is configured to: the threshold strength comprises an upper limit strength and a lower limit strength, the upper limit strength and the lower limit strength divide the value range of the signal strength into an upper limit range, a middle range and a lower limit range, and the value of the signal strength is judged to be in the upper limit range, the middle range or the lower limit range; generating the evaluation value configured to: and generating the evaluation value according to the value of the signal intensity in the upper limit interval, the middle interval or the lower limit interval.

3. The method of claim 2, wherein the upper strength limit and/or the lower strength limit are adjusted according to a signal gain or a signal attenuation generated by receiving the first set of wireless signals.

4. The inter-wireless-device distance identification method according to claim 1, wherein the distance or the range of the distance from the signal source is determined according to the evaluation values of n × m first wireless signals, and the method is configured to: accumulating evaluation values of n first wireless signals with the same power into a statistic value;

5. The method according to claim 4, wherein the distance between the signal sources or the distance range is determined according to the statistics of the m first wireless signals with different powers, and the method is configured to: respectively judging the quality grades of the m first wireless signals with different powers according to the statistical values;

6. The method of distance identification between wireless devices according to claim 2, wherein m-3,

the first wireless signal group comprises first wireless signals with low power, middle power and high power, and the values of the low power, the middle power and the high power are determined by the acquired nominal power;

obtaining the nominal power is configured to:

7. The method of inter-wireless-device distance identification according to claim 6, the method comprising:

8. The inter-wireless-device distance identification method of claim 7, wherein the close distance identification mechanism or the far distance identification mechanism is configured to divide the signal source into at least one inner zone within the reference distance and at least one outer zone outside the reference distance;

classifying the inner interval and the outer interval by different colors;

9. The method of inter-wireless-device distance identification according to claim 1, the method comprising:

transmitting n times a second set of wireless signals identical to the first set of wireless signals to the signal source, the second set of wireless signals including m second wireless signals corresponding to the first wireless signals, the second wireless signals for being received by the signal source and evaluating signal quality;

receiving the signal quality of the second wireless signal returned after the signal source evaluation;

and determining the distance of the signal source or the range of the distance according to the signal quality of the n x m first wireless signals and the signal quality of the n x m second wireless signals.

10. The method of inter-wireless-device distance identification according to claim 1, the method comprising:

evaluating signal quality of the set of secondary wireless signals;

determining the distance or the distance range according to the signal quality of the set of secondary wireless signals.

11. A system for identifying a distance between wireless devices, the system comprising a first distance identifying device and a second distance identifying device;

12. The inter-wireless-device distance identification system according to claim 11, wherein the first distance identification device and/or the second distance identification device is provided with a distance display module;