WO2012151932A1

WO2012151932A1 - Method and device for vertical positioning

Info

Publication number: WO2012151932A1
Application number: PCT/CN2011/082571
Authority: WO
Inventors: 张恺; 曾祥希; 李延波; 金磊; 吴明远
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-07-21
Filing date: 2011-11-21
Publication date: 2012-11-15
Also published as: CN102891722B; CN102891722A

Abstract

Disclosed are a method and device for vertical positioning. The method comprises: arranging multiple receiver antennae above a horizontal measurement line for use in positioning the vertical distance of a moving object; on the basis of the corresponding relation between power sequence standard deviations related to signal reception of the multiple receiver antennae and the vertical distance, pre-calculating the power sequence standard deviations corresponding to different vertical distances, and establishing a standard deviation list for storing each of the vertical distances and each of the power sequence standard deviations calculated; when vertically positioning the moving object, the multiple receiver antennae receiving a wireless signal transmitted by the moving object, then calculating a power sequence standard deviation thereof on the basis of the wireless signal, and by searching the standard deviation list, acquiring the vertical distance corresponding to the power sequence standard deviation. By pre-calculating the standard deviations corresponding to the different vertical distances, the present invention solves the problem of vertical positioning having great amount of calculations, complex algorithm, and requiring extended period of time.

Description

Method and device for longitudinal positioning

The present invention relates to the field of communications, and in particular, to a method and apparatus for longitudinal positioning. Background technique

The free-flow electronic charging method is a method of automatically charging a vehicle that is free to travel on multiple lanes by using an electronic charging technology on a toll road without physical isolation equipment. In this way, the vehicle can travel freely and has high traffic capacity, which is the basic form of urban congestion charging.

The roadside device and the in-vehicle device are the core devices of the free flow system. When the vehicle with the in-vehicle device passes through the area of the roadside device, the roadside device communicates with the in-vehicle device, and the roadside device reads the information of the in-vehicle device to obtain the vehicle. ID (identity, identity), model, license plate and other information, charge the legitimate vehicle, etc. If the vehicle is an illegal vehicle, the roadside equipment's linkage capture system captures the vehicle for subsequent fine inspection of illegal vehicles. Wait for the operation.

One problem that the free-flow system needs to solve is the following problem. When two or more vehicles can be accommodated in the trading area of the roadside equipment, if one of the vehicles is a legitimate vehicle and the other is an illegal vehicle, then The system cannot distinguish between legal and illegal vehicles and cause illegal vehicles to escape. Therefore, the free-flow system generally limits the width of the trading area of the roadside equipment. Considering the length of the vehicle body and the distance following the vehicle, the trading area is usually limited to 4 meters.

For the limitation of the transaction area of the roadside device, it is common practice to adjust the transmission power and angle of the antenna of the roadside device, and to limit the coverage of the antenna to the desired range as much as possible. However, such an approach cannot guarantee the accuracy of the transaction range. On the one hand, due to the presence of side lobes and other factors, it is impossible to accurately control the coverage of the antenna. On the other hand, due to the difference of the individual components of the vehicle, the sensitivity may be different. The difference in the distance of travel, resulting in a car bill It is possible for a dollar to trade with a roadside unit outside of the desired trading area.

Therefore, in addition to simply adjusting the power and angle of the antenna, other methods are needed to ensure the trading range. One solution is to know the longitudinal distance between the vehicle and the antenna. When the vehicle is outside the desired trading area, even if it responds to the road side. The signals of the unit are also not communicating. This requires a method of obtaining the longitudinal distance between the vehicle and the antenna. Some existing methods are generally based on the received

RSSI (Received Signal Strength Indication) directly calculates the distance. Some algorithms can also calculate the azimuth. However, most of these methods are computationally intensive, the algorithm is complex, or the calculation takes a long time. A DSP (Digital Signal Processing) chip is also required. Summary of the invention

It is an object of the present invention to provide a method and apparatus for longitudinal positioning, which can better solve the problem that the longitudinal positioning method has a large amount of calculation, the algorithm is complicated, and some need DSP chip assistance.

According to one aspect of the invention, a method of longitudinal positioning is provided, the method comprising the steps of:

Step A: setting a plurality of receiving antennas above the lateral measuring line for positioning the longitudinal distance of the moving object;

Step B: Calculate, according to a correspondence relationship between the standard deviation of the power sequence of the received signals and the longitudinal distance, calculate a power sequence standard deviation corresponding to different longitudinal distances, and establish and save each longitudinal distance and the calculated a standard deviation list of standard deviations of the respective power sequences; Step C: when longitudinally positioning the moving object, the plurality of receiving antennas receive a wireless signal transmitted by the moving object, and calculate a corresponding power sequence according to the wireless signal The standard deviation, and by looking up the standard deviation list, obtains a longitudinal distance corresponding to the standard deviation of the power sequence.

Wherein the longitudinal distance is a vertical distance of the moving object relative to the measuring line.

The step B includes: Step B1: Calculate antenna gain and spatial attenuation of each receiving antenna corresponding to different longitudinal distances;

Step B2: Calculate received power of each receiving antenna according to antenna gain and spatial attenuation of each receiving antenna;

Step B3: normalize the received power of each receiving antenna and calculate a normalized power sequence standard deviation.

The step B further includes: before calculating the antenna gain and the spatial attenuation:

Step B01, establishing a standard deviation list;

Step B02: Save the different longitudinal distances and their corresponding normalized power sequence standard deviations in the standard deviation list.

The step B1 includes:

Calculating an angle between the object corresponding to each longitudinal distance and a center line of each receiving antenna, and querying the antenna pattern according to the angle to obtain an antenna gain corresponding to different longitudinal distances of each receiving antenna.

The step C includes:

Step C1, when longitudinally positioning the moving object, the plurality of receiving antennas receive a wireless signal transmitted by the moving object, and calculate a received signal strength indicator RSSI;

Step C2: Convert the RSSI of each receiving antenna into power, and normalize the power of each receiving antenna, and calculate a standard deviation of the normalized power sequence;

Step C3: Search the standard deviation list according to the standard deviation of the normalized power sequence, and obtain a longitudinal distance corresponding to the standard deviation of the normalized power sequence.

According to another aspect of the present invention, there is provided a device for longitudinal positioning, the device comprising: a plurality of receiving antennas disposed above a lateral measuring line for locating a longitudinal distance of a moving object for receiving the emitted object wireless signal;

a pre-setting module, configured to utilize a power sequence of the plurality of receiving antennas with respect to receiving signals Corresponding relationship between the standard deviation and the longitudinal distance, pre-calculating the power sequence standard deviation corresponding to different longitudinal distances, and establishing a standard deviation list for storing the respective longitudinal distances and the calculated standard deviations of the respective power sequences;

And a controller, configured to calculate a power sequence standard deviation according to the wireless signal, and obtain a longitudinal distance corresponding to the standard deviation of the power sequence by searching the standard deviation list.

The pre-setting module includes:

a gain and attenuation calculation unit for calculating antenna gain and spatial attenuation of each receiving antenna corresponding to different longitudinal distances;

a power calculation unit, configured to calculate, according to antenna gain and spatial attenuation of each of the receiving antennas, a received power of each receiving antenna;

The standard deviation calculation unit is configured to normalize the received power of each of the receiving antennas and calculate a normalized power sequence standard deviation.

The controller further includes:

And a storage unit, configured to store the different longitudinal distances and their corresponding normalized power sequence standard deviations.

The pre-setting module is further configured to calculate an angle between an object corresponding to different longitudinal distances and a center line of each receiving antenna, and query an antenna pattern according to the angle to obtain an antenna gain of each of the receiving antennas.

Compared with the prior art, the beneficial effects of the present invention are:

The algorithm for measuring the longitudinal distance is simple and the calculation amount is small.

It can be applied not only to free-flow systems, but also to other applications where the longitudinal distance of the source is required. DRAWINGS

1 is a schematic diagram of a longitudinal positioning method according to an embodiment of the present invention;

2 is a schematic diagram of an initialization process provided by an embodiment of the present invention; 3 is a schematic diagram of a configuration of a longitudinal positioning system according to an embodiment of the present invention; FIG. 4 is a schematic diagram of a distance positioning process according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of receiving power of an antenna array antenna according to an embodiment of the present invention; FIG.

6 is a flowchart of calculating a standard deviation of different longitudinal distances according to an embodiment of the present invention; FIG. 7 is an L-S coordinate diagram provided by an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a longitudinal positioning device according to an embodiment of the present invention. detailed description

The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a longitudinal positioning method according to an embodiment of the present invention. As shown in FIG. 1, the method includes the following steps:

Step S101, a plurality of receiving antennas are disposed above a lateral measuring line for positioning a longitudinal distance of the moving object;

Step S102, according to the correspondence relationship between the standard deviation of the power sequence of the received signal and the longitudinal distance of the plurality of receiving antennas, pre-calculate the power sequence standard deviation corresponding to different longitudinal distances, and establish and save each longitudinal distance and the calculated a standard deviation list of standard deviations of the respective power sequences; Step S103, when longitudinally positioning the moving object, the plurality of receiving antennas receive a wireless signal transmitted by the moving object, and calculate a power sequence standard according to the wireless signal Poor, and by looking up the standard deviation list, obtain a longitudinal distance corresponding to the standard deviation of the power sequence.

The flow of the positioning vertical method provided by the embodiment of the invention is divided into two parts: an initialization process and a distance positioning process.

2 is a schematic diagram of an initialization process provided by an embodiment of the present invention. As shown in FIG. 2, the initialization process includes the following steps:

Step S201: Initialize system parameters.

Initialize system parameters, including antenna height h, antenna distance m, positioning accuracy, signal frequency f, where h is 6 meters, m is 0.95 meters, f is 5.8 GHz, the positioning accuracy is m/2, and the effective communication area is 5-8 meters in longitudinal direction.

For example, in FIG. 3, five receiving antennas R1, R2, R3, R4, and R5 are disposed in each lane. It is assumed that the source S is located at point A, and the abscissa X of A is closest to R3, that is, the offset k is less than or equal to m/. 2. The projection of the center of the lane, that is, the projection of R3 on the ground, is taken as the origin, and the direction of travel of the lane is the vertical axis. The line formed by the projection of the antenna on the ground is the horizontal axis, and the antennas R1, R2, R3, R4, and R5 are respectively disposed at -1.9m, -0.95m, 0m, 0.95m, 1.9m on the horizontal axis. Wherein, the longitudinal distance is the distance L between the source and the antenna array projected on the ground, and the measurement line is the projection of the antenna array on the ground.

Step S202, calculating standard deviations corresponding to different longitudinal distances.

Assuming that the power value of the signal transmitted from the source is P0, the power value Pn after receiving through the antenna is: Pn = P0 (Gn-Dn). Where G is the gain of the receiving antenna and D is the attenuation of the signal in free space. G is related to the angle between the antenna and the source. By calculating the angle between the antenna and the source and querying the antenna pattern, G can be obtained; and D is related to the signal frequency and the linear distance between the source and the antenna. Frequency, by calculating the linear distance between the antenna and the source, the attenuation of the signal in free space at this frequency is obtained. It can be seen that the received power Pn can be obtained by knowing the angle between the antenna and the source and the straight line distance.

First, calculate the angle α _η (n=l, 2, 3, 4, 5) between the source and the antenna Rn. As shown in Figure 3, the formula is: αι = cos ^-1 ( L ² + h ² / , /[2m + k| ² + L? + h ² ) 2= cos' ¹ ( l +- ² / /[m + k ²屮L? - li ² ) a ₃ = cos ^:_i ( - :h ² / k ² + L? 4- h ³ ) a ₄ = cos ^-1 ( ii ÷ h ³ /.^[m - k] - L? + h ² ') a ₅ = cos ^_i ( + h ² / [2m ― k] ² 4- L ² + h ² ) When k, m, and h are constants, the larger L is, the closer to 0, the smaller the difference between the two, that is, the closer the longitudinal distance of the source, the angle between the source and the different antennas of the antenna array. The larger the difference, the larger the difference in gain between different antennas of the antenna array, and vice versa. At the same time, in the case of the accuracy of m/2, the horizontal axis of the radio frequency tag can be considered to be located at the coordinates of the antenna receiving the maximum power, that is, k=0. Therefore only relevant to the longitudinal distance L.

Then, calculate the linear distance Ln from the source to the antenna Rn. As shown in Figure 3, the calculation formula for Ln is:

LI = _3⁄4 / [2m. + k] ³ + I + h ²

L2 = ^/ m + k] ² ÷ h ³

L3 = ² + 1 + li ²

L5 = .^ 201 - k] ² + ÷ h ²

Similar to a _n , when k, m and h are constant, the closer the source is to the longitudinal distance of the antenna array, the larger the signal difference received by each antenna in the antenna array. Similarly, in the case of an accuracy of m/2, the horizontal axis of the radio frequency tag can be considered to be at the coordinates of the antenna receiving the maximum power, that is, k=0. Therefore, the linear distance Ln between the antenna and the source is also only related to the longitudinal distance L.

Thus, the received power Pn can be expressed as Pn = P0(G(L) - D(L)) = P0*Gn(L). It can be seen that the power sequence of each antenna received signal at this time is not only related to the longitudinal distance, but also Transmit power P0 is related, so the power sequence is normalized to remove the influence of P0, then the received normalized power is: Pn(L) =

Gn(L, visible normalized power is only related to the longitudinal distance L. Therefore, the standard deviation of the normalized power = (Pn(L) - 1 / N) ² / N also corresponds to the longitudinal distance L.

According to the above analysis and formula, the standard deviation of different longitudinal distances L is calculated. Step S203, the obtained standard deviation is tabulated and stored in the memory of the controller.

The calculated standard deviation is made into a two-dimensional table related to k and longitudinal distance, that is, a standard deviation list, and the standard deviation list is stored in the controller's memory.

4 is a schematic diagram of a distance positioning process according to an embodiment of the present invention. When the source is closer to the antenna array, the difference between the signals received by the antennas is larger, as shown in FIG. 5, and the antennas are received. The standard deviation of the received signal power sequence reflects this fluctuation. If the signal power sequence received by each antenna is only related to the longitudinal distance, the standard deviation of the signal sequence can correspond to the longitudinal distance, thereby calculating the signal sequence. The standard deviation estimates the longitudinal distance of the source. As shown in Figure 4, the distance location process includes the following steps:

Step S301: The antenna receives the source signal.

When there is an onboard unit responding to the signal of the roadside unit, each receiving antenna receives the signal of the onboard unit and calculates the RSSI value.

Step S302, the antenna transmits the RSSI to the controller.

Step S303, the controller normalizes the power.

After receiving the RSSI value calculated by each antenna, the controller converts the RSSI into a power value and performs normalization processing.

Step S304, the controller calculates a variance of the normalized power.

Step S305, the controller looks up the table to determine the longitudinal distance.

The controller compares the variance calculated in step S304 with the value in the standard deviation list, so that the longitudinal distance range of the onboard unit can be obtained.

6 is a flow chart of calculating a standard deviation of different longitudinal distances according to an embodiment of the present invention. As shown in FIG. 6, the steps of calculating the standard deviation are as follows:

Step S401, calculating a linear distance between the tag and the antenna.

The linear distance between the tag and the antenna is calculated according to the calculation formula of Ln, wherein the label is assumed to be on the central axis, ie, the ordinate, the longitudinal distance is 1-12 meters, and the label step interval is 1 meter. According to Ln The calculated Ln is calculated as shown in the following table:

Step S402, calculating an angle between the label and the antenna center line.

Calculate the angle between the tag and the antenna centerline according to the calculation formula. The calculated values are as shown in the following table:

Step S403: Query the antenna pattern to obtain the antenna gain at the current angle.

According to the angle calculated in step S402, the corresponding antenna gain is searched in the antenna pattern. The invention is applicable to both directional antennas and omnidirectional antennas.

In this example, the antenna gains corresponding to different angles are found in the antenna pattern of the antenna as follows:

1 -3.299293009 3.61351139 15.86802828 1.963864886 -6.598586017

2 -1.963864886 4.241948154 15.86802828 2.670856245 -5.263157895

3 1.806755695 5.655930872 15.86802828 3.61351139 -3.063629222

4 5.027494108 7.227022781 15.86802828 5.34171249 -0.942655145

5 5.655930872 8.562450903 15.86802828 6.991358995 -0.157109191

6 4.320502749 10.05498822 15.86802828 8.483896308 -0.078554595

7 3.063629222 11.23330715 15.86802828 9.66221524 -0.078554595

8 1.963864886 12.0974077 15.86802828 10.84053417 -0.078554595

9 2.199528672 12.64728987 15.86802828 11.39041634 0.235663786

10 3.142183818 13.11861744 15.86802828 12.0974077 1.099764336

11 4.241948154 13.58994501 15.86802828 12.64728987 2.513747054

12 5.655930872 13.8256088 15.86802828 12.96150825 3.61351139 Step S404, calculate the free space attenuation.

According to the knowledge of electromagnetic waves, the attenuation of waves transmitted in free space is proportional to the distance of wave propagation. As shown in Equation 1:

D = 32.5+20*log(f)+20*log(Ln) ( dB ) Equation 1

The gain of the channel from the source transmitting antenna to the receiving antenna is theoretically determined by the above-mentioned receiving antenna gain and free space attenuation.

Calculate the free space attenuation value according to Equation 1. Where f is the set frequency of 5.8 GHz, and Ln is the linear distance between the tag and the antenna calculated in step S401. The calculation results are shown in the following table:

Step S405, calculating a difference between the antenna gain and the spatial attenuation.

Label distance

Off (m) antenna R1 antenna R2 antenna R3 antenna R4 antenna R5

1 -67.15418277 -59.94172705 -47.58254883 -61.59137355 -70.45347578

2 -66.12828562 -59.64411025 -47.9211315 -61.21520216 -69.42757863 3 -62.82906039 -58.73099239 -48.43265673 -60.77341187 -67.6994453

4 -60.19259471 -57.77629905 -49.06056503 -59.66160934 -66.16274397

5 -60.21562641 -57.12319086 -49.75382994 -58.69428277 -66.02866647

6 -62.2338495 -56.34099587 -50.47385656 -57.91208778 -66.63290685

7 -64.17975801 -55.87531075 -51.19472085 -57.44640266 -67.32194183

8 -65.95871172 -55.71017144 -51.90053159 -56.96704497 -68.0011312

9 -66.38286437 -55.83650014 -52.58239021 -57.09337367 -68.34672926

10 -66.07554132 -56.01405622 -53.23592068 -57.03526596 -68.11796081

11 -65.58433754 -56.16250492 -53.85952812 -57.10516007 -67.31253864

12 - 64.75159231 -56.51739676 -54.45325664 -57.38149731 -66.79401179 Step S406, the difference between the antenna gain and the spatial attenuation is converted from DB to a multiple.

The difference between the antenna gain and the spatial attenuation calculated in step S405 is converted into a multiple by the decibel DB, wherein the formula for calculating the multiple is: multiple=10 ( ^db/1G ) /1000, and the multiple value converted according to the formula is:

Step S407, normalization processing.

Since the transmission power of the OBU (On Board Unit) is different, the sum of the output powers is first normalized to avoid the standard deviation change caused by the difference in the OBU transmission power. The normalized power is calculated according to the normalized power formula Pn(L) = Gn(L) / ∑^ _{= 1} Gn(L), and the power value and normalized to 1 at the same distance. Where Gn(L) is the multiple calculated in step S406, and N is the number of antennas 5. The calculation results of the normalized power are shown in the following table:

Label distance antenna 1 antenna 2 antenna 3 antenna 4 antenna 5

1 0.00990706 0.05214232 0.897652344 0.035663642 0.004634634

2 0.013298528 0.059186291 0.880073605 0.041220374 0.006221202

3 0.030284785 0.077809261 0.833421802 0.048617133 0.00986702 4 0.058461879 0.101977024 0.758709874 0.06606498 0.014786243

5 0.063123994 0.128658365 0.70205982 0.089604297 0.016553524

6 0.04357471 0.169246568 0.653482259 0.117872007 0.015824455

7 0.030441203 0.206018651 0.605292831 0.143481976 0.014765339

8 0.02193007 0.232217018 0.558287659 0.173862808 0.013702445

9 0.021998039 0.24947119 0.527753828 0.18678115 0.013995792

10 0.025631869 0.25997332 0.492881293 0.205498098 0.01601542

11 0.030915098 0.270616259 0.45988746 0.217815295 0.020765888

12 0.04089516 0.272327478 0.438031634 0.223193431 0.025552298 Step S408, Calculate the standard deviation of the data as an indication of the degree of data concentration.

The standard deviation is calculated according to the standard deviation formula ^ ζ^/^^ ^ϋϊ^Τ^, where Pn(L) is the normalized power calculated in step S407, and N is the number of antennas 5. The calculated standard deviations are shown in the table below:

The standard deviation result is made into the LS coordinate chart. As shown in Fig. 7, it can be seen that the curve is monotonically decreasing. It can be seen from the figure that when the standard deviation is in the range of 0.21~0.28, the longitudinal distance is 5-8 meters. The label can be considered to be within the valid range.

FIG. 8 is a schematic structural diagram of a longitudinal positioning device according to an embodiment of the present invention. As shown in FIG. 8, the device includes a preset module 1, a plurality of receiving antennas 2, and a controller 3. The preset module 1 includes The gain and attenuation calculation unit 11, the power calculation unit 12, the standard deviation calculation unit 13, and the controller 3 include a storage unit 31. Presetting the module 1 for utilizing the correspondence between the standard deviation of the power sequence of the received signal and the longitudinal distance by using the plurality of receiving antennas, First calculating the standard deviation of the power sequence corresponding to different longitudinal distances, and establishing a standard deviation list for storing the respective longitudinal distances and the calculated standard deviations of the respective power sequences; the plurality of receiving antennas 2 are disposed on the lateral measuring line for locating the longitudinal distance of the moving object Above, the wireless signal for receiving the mobile object is transmitted; the controller 3 is configured to calculate a standard deviation of the power sequence according to the wireless signal, and obtain a standard deviation corresponding to the power sequence by searching the standard deviation list Longitudinal distance. The gain and attenuation calculation unit 11 is configured to calculate the antenna gain and the spatial attenuation of the respective receiving antennas corresponding to different longitudinal distances; the power calculating unit 12 is configured to calculate the receiving power of each receiving antenna according to the antenna gain and the spatial attenuation of the respective receiving antennas. The standard deviation calculation unit 13 is configured to normalize the received power of each of the receiving antennas and calculate a normalized power sequence standard deviation.

The pre-setting module 1 pre-calculates and stores the standard deviation of the normalized power sequence. For example, in Figure 3, the 4叚 label is on the center axis with a step spacing of 1 meter. The gain and attenuation calculation unit 11 first calculates the straight line distance Ln of the tag to the antenna Rn and the angle between the tag and the center line of the antenna Rn. The antenna gain Gn is obtained by looking up the antenna pattern by the angle. Let the frequency f = 5.8 GHz and calculate the free space attenuation Dn by the free space attenuation formula. The power calculation unit 12 calculates the received power Pn of the antenna based on the antenna gains Gn and Dn. The standard deviation calculation unit 13 normalizes the received power sequence Pn, calculates the standard deviation of the normalized power sequence, and makes the standard deviation into a two-dimensional representation related to the offset k and the longitudinal distance - The standard deviation list is stored in the storage unit 31 of the controller.

A plurality of receiving antennas 2 receive the source signal and pass the RSSI to the controller. When there is an onboard unit responding to the signal of the roadside unit, each receiving antenna 2 receives the signal of the onboard unit, calculates the RSSI value, and transmits it to the controller 3.

The controller 3 receives the wireless signal transmitted by the source radio frequency tag and determines the longitudinal distance based on the signal. After receiving the RSSI value calculated by each antenna 2, the controller 3 converts the RSSI into a power value, performs normalization processing, calculates the variance of the normalized power, and calculates the calculated variance and the standard in the storage unit 31. The values in the difference list are compared, that is, the longitudinal distance of the vehicle unit is obtained. Wai.

In summary, the present invention finds the feature quantity capable of characterizing the longitudinal distance, and forms the feature quantity into a table, and quickly obtains the result by the table lookup method, thereby solving the problem of large calculation amount and complicated algorithm when measuring the longitudinal distance. The problem that takes a long time has the advantages of simple algorithm and small calculation amount.

Although the invention has been described in detail above, the invention is not limited thereto, and various modifications may be made by those skilled in the art in accordance with the principles of the invention. Therefore, modifications made in accordance with the principles of the present invention should be construed as falling within the scope of the present invention. Industrial applicability

The invention solves the problem that the vertical positioning calculation amount is large, the algorithm is complicated, and the required time is long, by calculating the standard deviation corresponding to different longitudinal distances in advance.

Claims

Claim

1. A method of longitudinal positioning, the method comprising:

A. setting a plurality of receiving antennas above the lateral measuring line for locating the longitudinal distance of the moving object;

B. Calculate, according to the correspondence between the standard deviation of the power sequence of the received signals and the longitudinal distance, calculate a power sequence standard deviation corresponding to different longitudinal distances, and establish and save each longitudinal distance and each calculated a list of standard deviations of standard deviations of power sequences;

C. When longitudinally positioning the moving object, the multiple receiving antennas receive a wireless signal transmitted by the moving object, calculate a corresponding power sequence standard deviation according to the wireless signal, and search for the standard deviation list. And obtaining a longitudinal distance corresponding to the standard deviation of the power sequence.

2. The method according to claim 1, wherein

The longitudinal distance is the vertical distance of the moving object relative to the measurement line.

3. The method according to claim 2, wherein step B comprises:

B1. Calculating antenna gain and spatial attenuation of each receiving antenna corresponding to different longitudinal distances; B2, calculating receiving power of each receiving antenna according to antenna gain and spatial attenuation of each receiving antenna;

B3. Normally process the received power of each of the receiving antennas and calculate a normalized power sequence standard deviation.

4. The method according to claim 3, wherein the step B further comprises: before calculating the antenna gain and the spatial attenuation:

B01, establish a standard deviation list;

B02. Save the different longitudinal distances and their corresponding calculated normalized power sequence standard differences in the standard deviation list.

5. The method according to claim 4, wherein step B1 comprises:

Calculating an angle between an object corresponding to each longitudinal distance and a center line of each receiving antenna, and Querying the antenna pattern according to the included angle obtains antenna gains of the respective receiving antennas corresponding to different longitudinal distances.

6. The method according to any one of claims 1-5, wherein step C comprises:

Cl, in the longitudinal positioning of the moving object, the plurality of receiving antennas receive the wireless signal transmitted by the moving object, and calculate the received signal strength indicator RSSI;

C2, converting the RSSI of each receiving antenna into power, normalizing the power of each receiving antenna, and calculating a standard deviation of the normalized power sequence;

C3. Search the standard deviation list according to the standard deviation of the normalized power sequence to obtain a longitudinal distance corresponding to the standard deviation of the normalized power sequence.

7. A longitudinally positioned device, the device comprising:

a plurality of receiving antennas, configured to be disposed above a lateral measuring line for locating a longitudinal distance of the moving object, for receiving a wireless signal transmitted by the moving object;

a pre-setting module, configured to pre-calculate a power sequence standard deviation corresponding to different longitudinal distances by using a correspondence between the power sequence standard deviation of the received signals and the longitudinal distance, and establish and save each longitudinal distance and a calculated standard deviation list of standard deviations for each power sequence;

8. The apparatus according to claim 7, wherein the pre-setting module comprises: a gain and attenuation calculation unit, configured to calculate antenna gain and spatial attenuation of each receiving antenna corresponding to different longitudinal distances;

The device according to claim 8, wherein the controller further comprises: a storage unit, configured to store the different longitudinal distances and their corresponding normalized power sequence standard deviations.

The device according to claim 9, wherein the pre-setting module is further configured to calculate an angle between an object corresponding to different longitudinal distances and a center line of each receiving antenna, and obtain an antenna pattern according to the angle The antenna gain of each receiving antenna is described.