A Beacon signal preprocessing method, system and storage medium

Abstract

The present invention discloses a Beacon signal preprocessing method, system and storage medium, the method comprising: a mobile terminal scans a Beacon device once at a set time period and reads the RSSI value of the Beacon device; when the mobile terminal cannot scan the RSSI value of the Beacon device in a certain time period, according to the RSSI value of the Beacon device in the previous time period, a set attenuation model is used to calculate the attenuation value of the RSSI signal of the Beacon device, and the RSSI value of the Beacon device in the current time period is restored. By adopting the technical solution of the present invention, the missing Beacon signal can be restored, so as to locate the mobile terminal.

Description

Technical Field

[0001] The present invention relates to the field of indoor positioning, and in particular to a Beacon signal preprocessing method, system and storage medium. Background Art

[0002] When you are in other large buildings, you will find such a problem when you use Baidu or Amap to find the exit or store. The accuracy of GPS positioning is often not as good as outdoor navigation. This is because traditional outdoor positioning such as GPS and Beidou cause signal attenuation due to the building materials inside the building. In order to solve this problem of inaccurate indoor positioning, the industry proposed Beacon indoor positioning. Beacon-based indoor positioning can be used in indoor activities such as shopping guides, indoor crowd analysis, parking lot guidance, and intelligent guidance robots.

[0003] Beacon is a small low-power Bluetooth base station. These low-power Bluetooth beacon base stations continuously send out Beacon broadcast messages. After receiving the Beacon broadcast message, the terminal device equipped with the Bluetooth 4.0 module measures the received power and then enters it into the function of power attenuation and distance relationship to calculate the distance to the Beacon base station. By using the distance intersection from multiple Beacon base stations, multi-point positioning can be achieved.

[0004] Since indoor Beacon signals are scattered around with a transmission cycle (100-1000ms), the Beacon device signal receiving terminal needs to scan regularly to effectively detect the Beacon signal. Generally speaking, the transmission cycle of Beacon, the scanning quality of the terminal itself each time, and the scanning cycle determine the quality of the terminal detection signal. In most cases, due to the Beacon transmission cycle (the larger the cycle, the more energy-saving, and the lower the probability of being detected) and the terminal (cost) itself, the signal quality detected by the terminal is not high, resulting in the inability to detect effective signals sometimes, and the inability to locate due to the lack of signals. Summary of the invention

[0005] The purpose of the present invention is to provide a Beacon signal preprocessing method, system and storage medium to address the technical problem in the prior art that positioning cannot be performed due to the lack of Beacon signals.

[0006] In an embodiment of the present invention, a Beacon signal preprocessing method is provided, which includes:

[0007] The mobile terminal scans the Beacon device once every set time period and reads the RSSI value of the Beacon device;

[0008] When the mobile terminal cannot scan the RSSI value of the Beacon device in a certain time period, the attenuation value of the RSSI signal of the Beacon device is calculated using a set attenuation model based on the RSSI value of the Beacon device in the previous time period, and the RSSI value of the Beacon device in the current time period is restored.

[0009] In the embodiment of the present invention, the attenuation model is a far-away attenuation model, which is specifically as follows:

[0010]

[0011] Among them, RSSI leave is the RSSI signal attenuation value of the Beacon device, T is the set scanning time period, v is the moving speed of the mobile terminal, RSSB is the RSSI value of the Beacon signal received by the mobile terminal within 1 meter of the Beacon device, RSSIP is the RSSI value of the Beacon signal received by the mobile terminal in the previous cycle, and d is the distance between the handheld device and the Beacon in the current time window.

[0012] In the embodiment of the present invention, RSSI leave The value range is between [-1, -5].

[0013] In the embodiment of the present invention, the attenuation model is an inherited attenuation model, which is as follows:

[0014] Let h be the inheritance coefficient, and 0≤h≤1, RSSI inherit is the inherited attenuation value, then

[0015]

[0016] RSSI inherit The values ​​are as follows:

[0017]

[0018] In the embodiment of the present invention, the attenuation model is a joint attenuation model, which adopts both the inherited attenuation model and the remote attenuation model.

[0019] In the far-away attenuation model,

[0020] Among them, RSSI leaveis the RSSI signal attenuation value of the Beacon device, T is the set scanning time period, v is the moving speed of the mobile terminal, RSSB is the RSSI value of the Beacon signal received by the mobile terminal within 1 meter of the Beacon device, RSSIP is the RSSI value of the Beacon signal received by the mobile terminal in the previous cycle, and d is the distance between the handheld device and the Beacon in the current time window;

[0021] In the inheritance attenuation model, let h be the inheritance coefficient, and 0≤h≤1, RSSI inherit is the inherited attenuation value, then

[0022]

[0023] RSSI inherit The values ​​are as follows:

[0024]

[0025] In the joint attenuation model, let RSSI decay is the joint attenuation value, then

[0026] RSSI decay =RSSI leave +RSSI inherit .

[0027] In the embodiment of the present invention, in the joint attenuation model, RSSI decay The value range is between [-1, -7].

[0028] In an embodiment of the present invention, the Beacon signal preprocessing method further includes: performing dynamic weighted average processing on RSSI values ​​of multiple consecutive periods, and using the obtained dynamic average as new RSSI valid data to perform positioning calculations.

[0029] In the embodiment of the present invention, the RSSI values ​​of multiple consecutive periods are dynamically weighted averaged, specifically including:

[0030] The RSSI effective value set of multiple consecutive periods is recorded as R = {RSSI i}, and record the dynamic weighted average set as RM = {RSSIM i}, the dynamic mean calculation formula is as follows:

[0031] RSSIM i =(1-q)·RSSIM i-1 +q RSSI i ,

[0032] Wherein, i is the scan cycle count, q is the set weight factor, and 0≤q≤1.

[0033] In an embodiment of the present invention, a Beacon signal preprocessing system is further provided, which adopts the above-mentioned Beacon signal preprocessing method when preprocessing the Beacon signal received by the mobile terminal.

[0034] In an embodiment of the present invention, a storage medium is further provided, which stores a computer program. When the computer program is executed, the above-mentioned Beacon signal preprocessing method is executed.

[0035] Compared with the prior art, in the technical solution of the present invention, when the mobile terminal cannot scan the RSSI value of the Beacon device in a certain time period, the attenuation value of the RSSI signal of the Beacon device is calculated using a set attenuation model according to the RSSI value of the Beacon device read in the previous time period, thereby restoring the RSSI value of the Beacon device, so as to obtain a complete Beacon signal sequence, and solve the problem of unstable Beacon signals received by the terminal; in addition, a dynamic weighted average model based on time series is established, and this is used as a calculation model to calculate the effective value of the Beacon signal, and this value is used as a correction value of the measured value to participate in subsequent calculations, thereby improving the quality of the Beacon signal and making positioning more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural diagram of a Beacon positioning system according to an embodiment of the present invention.

[0037] Figure 2 It is a flowchart of a Beacon signal preprocessing method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] RSSIB: Beacon base station signal strength at a distance of 1 meter (dbm);

[0039] RSSI: The signal strength of the Beacon base station received by the mobile phone (dbm);

[0040] d ij : The straight-line distance between the mobile device and the Beacon base station ij;

[0041] in: i is the floor number, j is the equipment number belonging to the floor;

[0042] Time period: All Beacon signals are presented in an arithmetic progression with a time period T, t1, t2, t3…t n ; where t i -t i-1 =T; at a certain time point ti Start, continue for a time period T [t i ,t i+1 ) is the time window.

[0043] like Figure 1 As shown, in an embodiment of the present invention, a positioning system based on Beacon signals is provided, which includes a mobile terminal 1 with a positioning function, a central server 2 connected to the mobile terminal 1 via the Internet, and a plurality of Beacon base stations 3 arranged on each floor of a building. The mobile terminal 1 can be a mobile phone, or a smart device such as a tablet computer or a smart watch, which has a GPS locator and a Bluetooth Beacon module. A positioning and navigation APP is installed in the mobile terminal, and the received GPS signal and Beacon signal are uploaded to the central server 2 in real time. The central server 2 is used to receive and store information uploaded by various user mobile phones and provide navigation-related services.

[0044] like Figure 2 As shown, in an embodiment of the present invention, a Beacon signal preprocessing method is provided, which includes steps S1-S3, which are described below respectively.

[0045] Step S1: The mobile terminal scans the Beacon device once every set time period and reads the RSSI value of the Beacon device.

[0046] Step S2: Determine whether the signal of the Beacon device is scanned, if yes, execute step S4, otherwise, execute step S3.

[0047] It should be noted that when the mobile terminal is scanning the Beacon device, if the mobile terminal itself has a poor signal or is too far away from the Beacon device, it may fail to scan the signal of the Beacon device.

[0048] Step S3: According to the RSSI value of the Beacon device in the previous time period, the attenuation value of the RSSI signal of the Beacon device is calculated using a set attenuation model, and the RSSI value of the Beacon device in the current time period is restored.

[0049] Specifically, the attenuation model may be a remote attenuation model, an inherited attenuation model or a joint attenuation model. The above three attenuation models are described below respectively.

[0050] 1. Stay away from the decay model

[0051] When the device holder walks at speed v, if the Beacon device signal scanned in the previous time period is RSSIP, and no Beacon device signal is scanned in the current time period, it is likely that the device holder is moving away from the Beacon device. At this time, the reasonable solution is to inherit and use the signal strength (do attenuation processing. If the radiation distance is calculated based on the attenuated signal, let d be the distance between the handheld device and the Beacon in the current time window, and d' be the distance between the handheld device and the Beacon in the next time period. The following conditions should be met:

[0052] d'=d+v,

[0053] At this time, the signal attenuation value RSSI leave Requirements:

[0054]

[0055] Distance function

[0056]

[0057] Differentiating the variables d and RSSI, we can get:

[0058]

[0059] In practice, T is usually taken as 1s. To simplify the calculation, v is considered to be the median 1.1. According to different distances (d), RSSI leave The possible values ​​are as follows:

[0060] <![CDATA[RSSI leave (dbm)]]> d(m) -4.78 2 -2.39 4 -1.59 6 -1.19 8 -0.96 10

[0061] If rounded, RSSI leave The value range of is basically between [-1, -5].

[0062] 2. Inheritance Decay Model

[0063] Because the Beacon or the device itself cannot scan all signals, how much do we need to inherit the signals of the previous time window when calculating the current time window signal? Generally, the value range of this degree is between [0,1]. Let h be the inheritance coefficient, and 0≤h≤1, RSSI inherit is the inherited attenuation value, then

[0064]

[0065] RSSI inherit The values ​​are as follows:

[0066]

[0067] 3. Joint Attenuation Model

[0068] The combined attenuation and inherited attenuation are considered together, which is called joint attenuation. decay express.

[0069] The joint attenuation is defined to satisfy the following conditions:

[0070] d decay =d leave / h

[0071] When the inheritance coefficient h is 1, the signals are completely consistent, and the distance d decay =d leave

[0072] When the inheritance coefficient h is 0, there is no signal, and the distance d decay =∞

[0073] thereby:

[0074]

[0075] RSSI decay =RSSI leave +RSSI inherit

[0076] It can be concluded that joint attenuation = distance attenuation + inheritance attenuation.

[0077] In general, the combined attenuation value RSSID can take the following values:

[0078]

[0079] If rounded, the value range of RSSID is basically between [-1, -7].

[0080] Step S4: Perform dynamic weighted averaging on the RSSI values ​​of multiple consecutive cycles.

[0081] Perform dynamic weighted averaging of RSSI values ​​over multiple consecutive cycles, including:

[0082] The RSSI effective value set of multiple consecutive periods is recorded as R = {RSSI i}, and record the dynamic weighted average set as RM = {RSSIM i}, the dynamic mean calculation formula is as follows:

[0083] RSSIM i =(1-q)·RSSIM i-1 +q RSSI i ,

[0084] The meaning of the above formula is: RSSIMi-1 With RSSI i The weight ratio is calculated according to (1-q):q to calculate RSSIM i value, i is the scan cycle count, q is called the weight factor, which generally satisfies the condition 0≤q≤1; the commonly used values ​​of q are: 0, 0.5, 0.6, 0.8, 1, which can be adjusted according to the subsequent actual effect after calculation using this value.

[0085] In particular, when q = 1, RSSIM i =RSSI i At this time, the dynamic weighted average model value returns to the original effective value of RSSI.

[0086] After dynamically weighted averaging the RSSI values ​​of multiple consecutive cycles, the data obtained is smoother and more stable. The obtained dynamic average is used as the new RSSI valid data for positioning calculation, which can improve the Beacon signal quality and make positioning more accurate.

[0087] In an embodiment of the present invention, a Beacon signal preprocessing system is further provided, which adopts the above-mentioned Beacon signal preprocessing method when preprocessing the Beacon signal received by the mobile terminal.

[0088] In an embodiment of the present invention, a storage medium is further provided, which stores a computer program. When the computer program is executed, the above-mentioned Beacon signal preprocessing method is executed.

[0089] In summary, in the technical solution of the present invention, when the mobile terminal cannot scan the RSSI value of the Beacon device in a certain time period, the attenuation value of the RSSI signal of the Beacon device is calculated using a set attenuation model according to the RSSI value of the Beacon device read in the previous time period, thereby restoring the RSSI value of the Beacon device, so as to obtain a complete Beacon signal sequence, and solve the problem of unstable Beacon signals received by the terminal; in addition, a dynamic weighted average model based on time series is established, and this is used as a calculation model to calculate the effective value of the Beacon signal, and this value is used as a correction value of the measured value to participate in subsequent calculations, thereby improving the quality of the Beacon signal and making positioning more accurate.

[0090] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A Beacon signal preprocessing method, characterized in that: include: The mobile terminal scans the Beacon device once every set time period and reads the RSSI value of the Beacon device; When the mobile terminal cannot scan the RSSI value of the Beacon device in a certain time period, the attenuation value of the RSSI signal of the Beacon device is calculated using a set attenuation model based on the RSSI value of the Beacon device in the previous time period, and the RSSI value of the Beacon device in the current time period is restored.

2. The Beacon signal preprocessing method according to claim 1, characterized in that: The attenuation model is a far-from attenuation model, which is as follows: Among them, RSSI leave is the RSSI signal attenuation value of the Beacon device, T is the set scanning time period, v is the moving speed of the mobile terminal, RSSB is the RSSI value of the Beacon signal received by the mobile terminal within 1 meter of the Beacon device, RSSIP is the RSSI value of the Beacon signal received by the mobile terminal in the previous cycle, and d is the distance between the handheld device and the Beacon in the current time window.

3. The Beacon signal preprocessing method according to claim 1, characterized in that: RSSI leave The value range is between [-1, -5].

4. The Beacon signal preprocessing method according to claim 1, characterized in that: The attenuation model is an inherited attenuation model, which is as follows: Let h be the inheritance coefficient, and 0≤h≤1, RSSI inherit is the inherited attenuation value, then RSSI inherit The values ​​are as follows:

5. The Beacon signal preprocessing method according to claim 1, characterized in that: The attenuation model is a joint attenuation model, which uses both the inheritance attenuation model and the distance attenuation model. In the far-away attenuation model, Among them, RSSI leave is the RSSI signal attenuation value of the Beacon device, T is the set scanning time period, v is the moving speed of the mobile terminal, RSSB is the RSSI value of the Beacon signal received by the mobile terminal within 1 meter of the Beacon device, RSSIP is the RSSI value of the Beacon signal received by the mobile terminal in the previous cycle, and d is the distance between the handheld device and the Beacon in the current time window; In the inheritance attenuation model, let h be the inheritance coefficient, and 0≤h≤1, RSSI inherit is the inherited attenuation value, then RSSI inherit The values ​​are as follows: In the joint attenuation model, let RSSI decay is the joint attenuation value, then RSSI decay =RSSI leave +RSSI inherit 。 6. The Beacon signal preprocessing method according to claim 5, characterized in that: In the joint attenuation model, RSSI decay The value range is between [-1, -7].

7. The Beacon signal preprocessing method according to claim 1, characterized in that: Also includes: The RSSI values ​​of multiple consecutive cycles are dynamically weighted averaged, and the obtained dynamic average is used as the new RSSI valid data for positioning calculation.

8. The Beacon signal preprocessing method according to claim 7, characterized in that: Perform dynamic weighted averaging of RSSI values ​​over multiple consecutive cycles, including: The RSSI effective value set of multiple consecutive periods is recorded as R = {RSSI i }, and record the dynamic weighted average set as RM = {RSSIM i }, the dynamic mean calculation formula is as follows: RSSIM i =(1-q)·RSSIM i-1 +q·RSSI i , Wherein, i is the scan cycle count, q is the set weight factor, and 0≤q≤1.

9. A storage medium, characterized in that: A computer program is stored, and when the computer program is run, the Beacon signal preprocessing method according to any one of claims 1 to 8 is executed.

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