CN203178481U - Locating system based on intelligent mobile device - Google Patents
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- CN203178481U CN203178481U CN 201320168754 CN201320168754U CN203178481U CN 203178481 U CN203178481 U CN 203178481U CN 201320168754 CN201320168754 CN 201320168754 CN 201320168754 U CN201320168754 U CN 201320168754U CN 203178481 U CN203178481 U CN 203178481U
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Abstract
The utility model relates to a locating system based on an intelligent mobile device. A plurality of locators, which send radio signals, are configured, and the sent radio signals from the locators are received by the intelligent mobile device so that the locating of the intelligent mobile device is realized. A conventional intelligent mobile device is fully applied to act as a signal receiving and processing module so that a special and additional signals receiving and processing device is saved, and the whole locating system is simple in structure and low in cost. Meanwhile, the transmission speed of the radio signals is low and the relative bandwidth is large so that higher ranging accuracy can be realized and the position of the intelligent mobile device can be located more accurately.
Description
Technical Field
The utility model relates to an indoor positioning technology specifically is a positioning system based on intelligent Mobile device.
Background
With the development of smart phones, people can easily realize the positioning of geographic coordinates in a wide area environment by utilizing an onboard GPS module. The popularization of the positioning technology promotes people to pursue indoor accurate positioning service closer to life.
The existing positioning means mainly comprise satellite positioning (GPS), laser positioning, infrared positioning, Bluetooth positioning, Wifi positioning, Zigbee positioning, radar positioning, ultrasonic positioning and the like. However, the above positioning means can not meet the requirement of indoor precise positioning except for ultrasonic positioning, such as satellite positioning, which can only provide positioning of meter-level or dozens of meter-level outdoor wide area environment, and because of the shielding effect of ground buildings on satellite signals, the satellite positioning system is not suitable for indoor positioning. Laser positioning and infrared positioning are often applied to measuring instruments with extremely high precision requirements, and have the advantage of high precision, but the laser positioning and the infrared positioning need relatively complex hardware modules, and optical signals are extremely little diffused in a transmission range, so that common users need calibration and are extremely inconvenient to use, and the use cost of the users is high. The RF technologies such as bluetooth positioning, Wifi positioning, Zigbee positioning cannot obtain high positioning accuracy when applied to an indoor positioning system because the bandwidth of the physical layer signal is low. The radar technology has the advantages of long measuring distance and strong penetrating power, and occupies an extremely important position in a measuring and positioning system, but the radar system has high cost, large power consumption, strong radiation and inconvenient operation, and has serious indoor clutter interference, so the radar positioning is not suitable for common users. Ultrasonic positioning, the most famous MIT's Cricket technique uses comparatively clean 40KHz ultrasonic wave to measure the distance, and the precision is better, but it needs the user side to use the ultrasonic wave, and uses Zigbee to synchronize, needs special equipment just can support like this for whole ultrasonic positioning technique cost is high, and consequently ordinary user uses the difficulty, and it is difficult to promote.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that among the prior art indoor accurate positioning equipment cost is high problem to a low in cost's positioning system based on intelligent Mobile device is provided.
In order to solve the technical problem, the utility model discloses a realize through following technical scheme:
a smart mobile device based positioning system, the system comprising:
at least three locators each for broadcasting an audio signal including a locator ID;
a smart mobile device comprising a microphone and a processor, wherein,
the microphone is used for passively receiving the audio signal sent by the locator and sending the audio signal to the processor;
the processor further comprises a time calculation module and an intelligent mobile equipment positioning module; wherein,
the time calculation module is used for receiving the audio signal sent by the microphone, analyzing the audio signal to obtain a locator ID, calculating the time TOA of the audio signal reaching the intelligent mobile equipment, and sending the TOA of the locator with the corresponding ID number and the locator ID number to the intelligent mobile equipment positioning module and the server;
the intelligent mobile equipment positioning module receives the TOA from the at least three positioners to the intelligent mobile equipment and the absolute coordinates of the corresponding ID number positioner, which are sent by the time calculation module, calculates the absolute coordinates of the intelligent mobile equipment and outputs the absolute coordinates;
the server receives the locator ID sent by the time calculation module, inquires the absolute coordinate of the locator corresponding to the locator ID in a database, and sends the inquired absolute coordinate of the locator corresponding to the ID number to the intelligent mobile equipment positioning module;
and the database is used for storing the locator ID and the absolute coordinates of the locator corresponding to the locator ID.
The time calculation module further comprises an audio signal analysis unit, a TOA measurement unit and a TOA estimation unit; wherein,
the audio signal analysis unit analyzes the received audio signal to obtain a locator ID and sends the locator ID to the TOA estimation unit;
the TOA measuring unit receives the audio signal, obtains a TOA measuring value by threshold detection of the received audio signal, and sends the TOA measuring value to a TOA estimating unit;
the TOA estimation unit receives the locator ID sent by the audio signal analysis unit and the TOA measured value, carries out TOA estimation calculation on the TOA measured value to obtain the final TOA, and sends the TOA of the locator with the corresponding ID number to the intelligent mobile equipment positioning module.
The frequency band of the audio signal is 15Khz to 24 Khz.
The audio signal has a base bandwidth of 1 Khz.
The locator generates the audio signal using BPSK or orthogonal coding.
The IDs of a plurality of said locators are identified by different multi-user orthogonal codes.
Each of the locators includes a time synchronization unit for synchronizing or coordinating broadcast times of a plurality of the locators.
The intelligent mobile equipment is a mobile phone or a PDA or a Tablet or a notebook computer.
Compared with the prior art, the technical scheme of the utility model have following advantage:
(1) the utility model discloses a positioning system based on intelligent mobile device, through setting up a plurality of locators that send audio signal, utilize intelligent mobile device to receive the audio signal of locator broadcast, and then realize the location of intelligent mobile device; the existing intelligent mobile equipment is fully utilized as a signal receiving and processing module, so that special signal receiving and processing equipment is omitted, and the whole positioning system is simple in structure and low in manufacturing cost; meanwhile, the signal source is an audio signal, the transmission speed is low, the relative bandwidth is large, high ranging precision can be obtained, and the position of the intelligent mobile device can be accurately located. The whole positioning process is passive receiving of the intelligent mobile device at the user end, so that no theoretical user number limitation exists.
(2) The TOA estimation unit further accurately estimates the TOA according to the TOA measured value detected by the TOA measurement unit, thereby effectively reducing the TOA additional time delay error generated by multipath effect and further improving the positioning precision. And audio signal adopt the 15Khz that the people's ear can not hear to 24Khz frequency channel, can satisfy the signal requirement of accurate location promptly, do not have noise pollution again. The audio signal adopts BPSK or orthogonal coding, and the locator ID adopts multi-user orthogonal code identification, so that the anti-noise performance of the system is improved, and the system is more stable. The time synchronization unit of the timer calibrates the whole system, so that the TOA time is more accurate and the positioning is more accurate.
Drawings
In order that the present invention may be more readily and clearly understood, reference will now be made in detail to the present invention, which is illustrated in the accompanying drawings,
fig. 1 is a schematic structural diagram of a positioning system based on an intelligent mobile device according to an embodiment of the present invention;
fig. 2 is a schematic diagram of TDOA location of an intelligent mobile device based location system according to an embodiment of the present invention;
fig. 3 is a flowchart of a positioning method of a positioning system based on an intelligent mobile device according to an embodiment of the present invention.
Wherein the reference numerals are:
1-a first locator, 2-a second locator, 3-a third locator.
Detailed Description
Example 1
Referring to fig. 1, a positioning system based on an intelligent mobile device according to an embodiment of the present invention includes:
as a specific implementation manner, the locator is identified by using a multi-user orthogonal code, that is, different locator IDs are identified by using different multi-user orthogonal codes, and the audio signal is broadcast after the audio signal is orthogonally encoded (such as BPSK), so that the anti-interference capability of the signal can be effectively improved by using the multi-user orthogonal code, and the BPSK encoding is simple and efficient to improve the response speed of the system; a simple reference time mechanism is arranged in the locator, and one or more distributed main control locators send time synchronization signals before sending audio signals each time; simple time synchronization may also be used to enhance ranging and positioning stability. As a specific implementation mode, digital narrow pulses with carrier frequencies of 15K to 24K are directly generated on the positioner in a digital mode, the narrow pulses are transmitted through 2-PAM modulation (pulse transmission represents 1, and no pulse transmission represents 0), and the modulated digital pulses are transmitted through a low-power horn. The processing ensures that the transmitting part of the whole locator only needs one singlechip and one amplifier. As another embodiment of the present invention, the number of the positioning devices is not less than three, for example, four, nine, etc.
A mobile phone, including a microphone and a processor, of course, as other embodiments of the present invention, the mobile phone may be replaced by other intelligent mobile devices, such as a mobile phone having information processing capability and an audio receiving unit and a PAD or a Tablet or a notebook computer; wherein,
the microphone is used for receiving the audio signal sent by the locator and sending the audio signal to the processor;
the processor further comprises a time calculation module and a mobile phone positioning module; wherein,
as a specific implementation manner, the Time calculation module further includes an audio signal analysis unit, a TOA (Time of Arrival) measurement unit, and a TOA estimation unit; the audio signal analysis unit analyzes the received audio signal to obtain a locator ID and sends the locator ID to the TOA estimation unit; the TOA measuring unit receives the audio signal, obtains a TOA measuring value by threshold detection of the received audio signal, and sends the TOA measuring value to a TOA estimating unit; the TOA estimation unit receives the locator ID and the TOA measured value sent by the audio signal analysis unit, carries out TOA estimation calculation on the TOA measured value to obtain the final TOA, and sends the TOA and the locator ID number of the locator with the corresponding ID number to a mobile phone positioning and server. The time calculation module can be used by burning the existing program for realizing time calculation.
And the mobile phone positioning module receives the TOA from the three positioners to the intelligent mobile equipment, which is sent by the time calculation module, and the absolute coordinates of the corresponding ID number positioner, which is sent by the server, and outputs the absolute coordinates. The mobile phone positioning module can be used by only burning the existing corresponding positioning program.
The server receives the locator ID sent by the time calculation module, inquires the absolute coordinate of the locator corresponding to the locator ID in a database, and sends the inquired absolute coordinate of the locator corresponding to the corresponding ID number to the mobile phone positioning module;
and the database is used for storing the locator ID and the absolute coordinates of the locator corresponding to the locator ID. As another embodiment of the present invention, the server and the database may be respectively provided by different servers.
As a specific implementation manner, in this embodiment, the base bandwidth of the audio signal is 1Khz, the frequency band is 15Khz-24Khz, the effective bandwidth is improved by generating a pulse signal to shorten the signal rise time, the positioning accuracy can reach the centimeter level according to CRLB (which is called Cramer-Rao Lower Bound, meaning the Lower Bound principle of the estimated variance), and the audio signal in the frequency band of 15Khz-24Khz cannot be heard by human ears but can be detected by a microphone of a mobile phone, so that environmental noise pollution is not caused. The locator ID adopts multi-user orthogonal code identification, the anti-jamming capability is strong, and the locator ID number is not easily tampered by noise.
As the utility model discloses above-mentioned embodiment's a positioning method based on positioning system of intelligent mobile device, including following step:
s0: setting a master control locator, wherein the master control locator sends a time synchronization signal in a broadcasting mode, and other locators receive the time synchronization signal and calibrate the time of the locators;
s1: the locator carries out multi-user orthogonal code identification on the ID number of the locator, loads the ID number and the sending time of the locator to an audio signal, carries out BPSK coding on the audio signal, and broadcasts the audio signal when the sending time is up;
s2: a microphone in the mobile phone receives the audio signal sent by the locator and sends the audio signal to a time calculation module;
s3: the time calculation module analyzes the audio signal, wherein
S31: the audio signal analysis unit analyzes the received audio signal to obtain a locator ID and sends the locator ID to the TOA estimation unit;
s32: the TOA measuring unit receives the audio signal, obtains a TOA measuring value by threshold detection of the received audio signal, and sends the TOA measuring value to a TOA estimating unit; as a specific embodiment, the time of the rising edge of the TOA can be detected to obtain the distance value by using the method of edge threshold detection TOA. Therefore, the utility model discloses the actual range finding precision of positioning method based on intelligent mobile device depends on the rising steepness degree of received signal, namely effective bandwidth; and the utility model discloses an audio signal's transmission speed is low, and relative bandwidth is big, can obtain very high range finding precision to very good condition is provided for accurate indoor location.
S33: the TOA estimation unit receives the locator ID and the TOA measured value sent by the audio signal analysis unit, and carries out TOA estimation calculation on the TOA measured value, and a plurality of existing algorithms can be used for TOA estimation so as to obtain the final TOA and send the TOA of the locator with the corresponding ID number to a mobile phone positioning device;
s4: the server receives the locator ID sent by the time calculation module, inquires the absolute coordinate of the locator corresponding to the locator ID in a database, and sends the inquired absolute coordinate of the locator corresponding to the corresponding ID number to the mobile phone positioning module;
s5: and the mobile phone positioning module receives TOAs from the three positioners to the mobile phone sent by the time calculation module and absolute coordinates of the corresponding ID number positioner sent by the server.
As a specific mobile phone positioning method of the above embodiment of the present invention, as shown in fig. 2, it is set that the three locators are respectively the first locator 1, the second locator 2, and the third locator 3, and the arrival time of the first locator 1 reaching the mobile phone is TOA1The second positioner2 the arrival time of the mobile phone is TOA2The arrival time of the third locator 3 at the mobile phone is TOA3，TDOA1Is TOA1And TOA2Difference of (1), TDOA2Is TOA2And TOA3Difference of (1), TDOA3Is TOA1And TOA3Difference of (D), L1As TDOA1Multiplied by the speed of sound, L2As TDOA2Multiplied by the speed of sound, L3As TDOA3Multiplied by the speed of sound; the absolute coordinates of the first locator 1 and the second locator 2 are taken as the focal points, L1Constructing hyperbolas H for constant values1The hyperbola H1One of the hyperbolas which is farther than the positioner having the larger middle-distance TOA value is taken as a hyperbola H1' similarly, H can be obtained2’,H3'; any two single-sided hyperbolas H1’、H2' and H3The intersection point coordinate of' is the absolute coordinate of the mobile phone, and if three unilateral hyperbolas are adopted, the positioning accuracy is higher. As specific examples of other methods for implementing positioning, all methods for implementing positioning based on TOA exist, including a method for implementing positioning based on TOA used in a GPS positioning system.
The utility model discloses utilize the cell-phone microphone to receive audio signal that the locator sent comes the location, and the current smart mobile phone of make full use of has saved special signal reception and processing module as signal reception and processing module, whole positioning system simple structure, advantage that the cost is low.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (8)
1. A smart mobile device based positioning system, the system comprising:
at least three locators each for broadcasting an audio signal including a locator ID;
a smart mobile device comprising a microphone and a processor, wherein,
the microphone is used for passively receiving the audio signal sent by the locator and sending the audio signal to the processor;
the processor further comprises a time calculation module and an intelligent mobile equipment positioning module; wherein,
the time calculation module is used for receiving the audio signal sent by the microphone, analyzing the audio signal to obtain a locator ID, calculating the time TOA of the audio signal reaching the intelligent mobile equipment, and sending the TOA of the locator with the corresponding ID number and the locator ID number to the intelligent mobile equipment positioning module and the server;
the intelligent mobile equipment positioning module receives the TOA from the at least three positioners to the intelligent mobile equipment and the absolute coordinates of the corresponding ID number positioner, which are sent by the time calculation module, calculates the absolute coordinates of the intelligent mobile equipment and outputs the absolute coordinates;
the server receives the locator ID sent by the time calculation module, inquires the absolute coordinate of the locator corresponding to the locator ID in a database, and sends the inquired absolute coordinate of the locator corresponding to the ID number to the intelligent mobile equipment positioning module;
and the database is used for storing the locator ID and the absolute coordinates of the locator corresponding to the locator ID.
2. The positioning system of claim 1, wherein the time calculation module further comprises an audio signal analysis unit, a TOA measurement unit and a TOA estimation unit; wherein,
the audio signal analysis unit analyzes the received audio signal to obtain a locator ID and sends the locator ID to the TOA estimation unit;
the TOA measuring unit receives the audio signal, obtains a TOA measuring value by threshold detection of the received audio signal, and sends the TOA measuring value to a TOA estimating unit;
the TOA estimation unit receives the locator ID sent by the audio signal analysis unit and the TOA measured value, carries out TOA estimation calculation on the TOA measured value to obtain the final TOA, and sends the TOA of the locator with the corresponding ID number to the intelligent mobile equipment positioning module.
3. A smart mobile device based location system according to claim 1 or 2, wherein the frequency band of the audio signal is 15Khz to 24 Khz.
4. A smart mobile device based positioning system according to claim 1 or 2, wherein the audio signal has a base bandwidth of 1 Khz.
5. The smart mobile device-based positioning system according to claim 1 or 2, wherein the locator uses BPSK or orthogonal coding to generate the audio signal.
6. A smart mobile device based location system according to claim 1 or 2, wherein the IDs of a plurality of said locators are identified by different multi-user orthogonal codes.
7. A smart mobile device based location system according to claim 1 or 2, wherein each of said locators comprises a time synchronization unit for synchronizing or coordinating broadcast times of a plurality of said locators.
8. A positioning system based on smart mobile device as claimed in claim 1 or 2, wherein the smart mobile device is a mobile phone or PDA or Tablet or notebook computer.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104101863A (en) * | 2013-04-07 | 2014-10-15 | 苏州红亭信息科技有限公司 | Locating system based on intelligent mobile device and locating method |
| CN104793184A (en) * | 2014-01-20 | 2015-07-22 | 刘笑羽 | Portable wireless network terminal positioning method |
| CN105652244A (en) * | 2015-12-31 | 2016-06-08 | 上海酷远物联网科技有限公司 | Mobile terminal positioning method, acoustic positioning transmitter-receiver, mobile terminal and mobile terminal positioning system |
| WO2016127333A1 (en) * | 2015-02-11 | 2016-08-18 | Harman International Industries, Incorporated | Mobile device positioning |
| CN107015230A (en) * | 2017-03-15 | 2017-08-04 | 中国人民解放军63655部队 | A kind of ultrasonic ranging method |
| CN107450052A (en) * | 2016-05-31 | 2017-12-08 | 华为终端（东莞）有限公司 | A kind of method, system and the relevant device of indoor navigation positioning |
| CN110568408A (en) * | 2019-08-31 | 2019-12-13 | 苏州普息导航技术有限公司 | Audio positioning system and method based on single signal source |
| CN112697152A (en) * | 2020-12-29 | 2021-04-23 | 恒玄科技(上海)股份有限公司 | Positioning method, electronic device and storage medium |
-
2013
- 2013-04-07 CN CN 201320168754 patent/CN203178481U/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104101863A (en) * | 2013-04-07 | 2014-10-15 | 苏州红亭信息科技有限公司 | Locating system based on intelligent mobile device and locating method |
| CN104793184A (en) * | 2014-01-20 | 2015-07-22 | 刘笑羽 | Portable wireless network terminal positioning method |
| WO2016127333A1 (en) * | 2015-02-11 | 2016-08-18 | Harman International Industries, Incorporated | Mobile device positioning |
| CN105652244A (en) * | 2015-12-31 | 2016-06-08 | 上海酷远物联网科技有限公司 | Mobile terminal positioning method, acoustic positioning transmitter-receiver, mobile terminal and mobile terminal positioning system |
| CN107450052A (en) * | 2016-05-31 | 2017-12-08 | 华为终端（东莞）有限公司 | A kind of method, system and the relevant device of indoor navigation positioning |
| CN107450052B (en) * | 2016-05-31 | 2020-01-21 | 华为终端有限公司 | Indoor navigation positioning method, system and related equipment |
| CN107015230A (en) * | 2017-03-15 | 2017-08-04 | 中国人民解放军63655部队 | A kind of ultrasonic ranging method |
| CN107015230B (en) * | 2017-03-15 | 2019-12-06 | 中国人民解放军63655部队 | ultrasonic ranging method |
| CN110568408A (en) * | 2019-08-31 | 2019-12-13 | 苏州普息导航技术有限公司 | Audio positioning system and method based on single signal source |
| CN112697152A (en) * | 2020-12-29 | 2021-04-23 | 恒玄科技(上海)股份有限公司 | Positioning method, electronic device and storage medium |
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