CN109959921A - A kind of acoustical signal method for estimating distance based on Beidou time service - Google Patents
A kind of acoustical signal method for estimating distance based on Beidou time service Download PDFInfo
- Publication number
- CN109959921A CN109959921A CN201910155577.2A CN201910155577A CN109959921A CN 109959921 A CN109959921 A CN 109959921A CN 201910155577 A CN201910155577 A CN 201910155577A CN 109959921 A CN109959921 A CN 109959921A
- Authority
- CN
- China
- Prior art keywords
- signal
- beidou
- module
- ref
- time service
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S11/00—Systems for determining distance or velocity not using reflection or reradiation
- G01S11/14—Systems for determining distance or velocity not using reflection or reradiation using ultrasonic, sonic, or infrasonic waves
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
The invention discloses a kind of acoustical signal method for estimating distance based on Beidou time service, the present invention realizes that beaconing nodes are synchronous with the high precision clock between label node using Beidou satellite navigation system, after label node receives beaconing nodes transmitting modulation acoustical signal, acoustic signal propagation time delay is estimated by the elimination of filtering, cross-correlation and multipath, and then obtains the range estimation between beaconing nodes and label node.Acoustical signal method for estimating distance of the invention is repeatedly interacted without additional synchronization node and acoustical signal, sub-meter grade range accuracy is provided by the timing function that Beidou satellite navigation system provides with lower cost, the present invention is not only suitable for the stronger outdoor environment of Beidou signal, and is suitable for the weaker indoor environment of Beidou signal.
Description
Technical field
The invention belongs to positioning fields, and in particular to a kind of acoustical signal method for estimating distance based on Beidou time service.
Background technique
Twentieth century nineties, the global positioning systems such as GPS start to play the part of more and more important angle in people's lives
Color, location information become more and more important.But the satellite positioning system accuracies such as GPS, Beidou are not high, and civil product is in room
Outer highest also can only achieve 5 meters of precision.And indoors, since signal is seriously blocked by building, global position system due to
The number of satellite that can connect to is very few, or even is unable to get location information.And it is based on location-based service (Location-Base
Service) application scenarios indoors are same extensive, including sports science, public safety, intelligent plant, indoor navigation etc..
The passage of time at any time, electronic technology and the communication technology are rapidly developed.The miniaturization of integrated circuit with
Low priceization, smart phone starts to occur and rapid proliferation, the soil of indoor positioning technologies are mature.Then, academia and work
Industry begins to focus on indoor positioning technologies, and a series of correlative study occurs.
Tacldng medium common at present includes Wi-Fi, bluetooth, ultra wide band, ultrasonic wave, earth magnetism, image etc., wherein compatible intelligence
Energy mobile phone mainly has Wi-Fi, bluetooth and earth magnetism.In existing research with application, the precision of these three localization methods is not
Height, generally at 1~10 meter.Also, Wi-Fi and earth magnetism are protected from environmental bigger, and environment changes after a period of time
It just needs to calibrate again；Bluetooth is current most popular Mobile Location Technology, but needs to lay a large amount of Bluetooth base. station, often
The coverage area of a Bluetooth base. station is no more than 10 meters.The available higher precision of the method for ultra wide band, but since it is used
Electromagnetic wave needs high synchronization accuracy, and incompatible mobile phone as ranging medium, thus application is limited.
Localization method common at present includes the localization method (Direction of Arrival, DOA) based on angle, base
In the localization method (Time of Arrival, TOA) of distance measuring, the localization method (Time measured based on range difference
Difference of Arrival, TDOA) and the localization method based on fingerprint base etc..Based on the localization method of distance measuring because
Its precision is high, has obtained relatively broad application using convenient.But one of this method is on condition that need to different nodes
Time synchronizes, and can accurately just measure the transmission time of medium, and then estimates range information.Ultra wide band is adopted due to it
It uses electromagnetic wave as ranging medium, needs high positioning accuracy, therefore usually synchronized using wired connection, lay base
It stands relatively complicated.And using acoustical signal as ranging medium, since acoustic signal propagation speed is far below electromagnetic wave, thus can be square
Being synchronized by wireless network just.The currently used method of synchronization includes RBS (Reference Broadcast
Synchronization), TPSN (Timing-sync Protocol for Sensor Networks) etc., RBS synchronous method
An additional central node is needed, also results in unstability while increasing hardware cost；And TPSN synchronous method is only
It can be carried out between two nodes, the case where multinode is taken a long time and synchronization accuracy is lower.
Summary of the invention
In view of the deficiencies of the prior art, the present invention proposes a kind of acoustical signal method for estimating distance based on Beidou time service, should
Method is not necessarily to additional synchronization node, the timing function provided by Beidou satellite navigation system, is provided with lower cost remote
The ranging and positioning accuracy of super Beidou satellite navigation system, the indoor environment weak suitable for Beidou signal or need precision distance measurement
Or the outdoor environment of positioning accuracy, excellent basis is provided for positioning system.
Technical solution used by this method is as follows: a kind of acoustical signal method for estimating distance based on Beidou time service, the party
Method the following steps are included:
(1) the identical PPS pulse period is set by the beidou timing module of all nodes；
(2) after beaconing nodes receive Beidou time service PPS pulse, the external interrupt of processor is triggered, beaconing nodes are at once
Issue the high-frequency chirp signal through ovennodulation；
(3) after label node receives Beidou time service PPS pulse, the external interrupt of processor, label node record are triggered
Under this moment local clock at the time of t0；
(4) label node constantly monitors acoustical signal, the acoustical signal that will be received, and noise is eliminated in progress high-pass filtering first,
Computing cross-correlation is then normalized using the method for sliding window and reference signal, judges whether to receive beacon section in step (3)
The modulated signal that point issues, if then carrying out next step；Otherwise, continue to monitor acoustical signal；
(5) after label node receives the modulated signal that beaconing nodes issue, using the ratio threshold method for eliminating multipath
It determines the first diameter that acoustical signal reaches, thus estimates the arrival time t of signal1, then range estimation d=(t1-t0) c, wherein
C is the velocity of sound.
Further, the beaconing nodes are mainly by loudspeaker module, first microprocessor, the first Beidou time service
Module, the first power module composition, loudspeaker module, the first beidou timing module and the first power module with the first micro process
Device is connected.
Further, the label node is mainly by microphone module, the second microprocessor, the second Beidou time service mould
Block, second power supply module, wireless communication module composition, microphone module, the second beidou timing module, wireless communication module and the
Two power modules are connected with the second microprocessor.
Further, described, the high-frequency chirp signal signal of the modulationref(m), expression formula are as follows:
signalref(m)=cos (2 π m (f0+rate*m))
Wherein, m indicates that sampling number, rate are the slope of linear FM signal, initial frequency f0With termination frequency f1It is big
In 18000Hz, signal length T is in 0.04~0.05s.
Further, the method for the sliding window is normalized computing cross-correlation with reference signal and includes the following steps:
(A1) label node often receives n sampled point and is known as a frame, and it is (preceding to be classified as preceding fieldIt is a) and rear field
(afterIt is a), this frame data is denoted as signal2(m), the preceding field of the rear field of previous frame and this frame data is spliced and is denoted as
signal1(m), wherein m represents m-th of sampled point；
(A2) by signal1(m) and signal2(m) respectively with reference signal signalref(m) cross-correlation is normalized
Operation, calculation method are as follows:
Wherein, exp represents the exponent arithmetic using e the bottom of as；I is imaginary unit；S1It (k) is signal1(m) discrete Fu is carried out
In leaf transformation as a result, representing signal1(m) mutually it is worth in the width of k frequency component；S2It (k) is signal2(m) direct computation of DFT is carried out
Leaf transformation as a result, representing signal2(m) mutually it is worth in the width of k frequency component；SrefIt (k) is signalref(m) it carries out discrete
Fourier transformation as a result, representing signalref(m) mutually it is worth in the width of k frequency component；R1(τ) is signal1(m) and with reference to letter
Number signalref(m) normalized crosscorrelation is as a result, indicate difference τ moment signal1(m) and signalref(m) related journey
Degree；R2(τ) is signal2(m) with reference signal signalref(m) normalized crosscorrelation as a result, indicate difference the τ moment
signal2(m) and signalref(m) degree of correlation；
(A3) by R1BeforeA point R2BeforeA point splices and is denoted as Corr, returns to step (A1).
Further, the ratio threshold method the following steps are included:
(B1) the maximum value maxC and its position maxi of Corr are calculated, it may be assumed that
Max (Corr)=maxC=Corr (maxi)
When meeting the following conditions, then continue next step:
max(signal2) > thresholdsignal
Max (Corr) > thresholdR
Wherein, thresholdsignalIt is a constant related with speaker gain, thresholdRIt is and signal detection
The relevant constant of sensitivity；
(B2) from the preceding threshold of maxilengthA sampled point, i.e. maxi-thresholdlengthStart, searches backward
It seeks, until finding first point j for meeting the following conditions:
Corr (j) > vRatioTh*max (Corr)
Wherein, thresholdlength, vRatioTh is two constants related with environment reverberation degree；
(B3) signal arrival timeWherein fs is the sample rate of voice signal, signal transmission delay Δ t=t1-
t0。
Beneficial effects of the present invention are as follows: the invention proposes a kind of high-precision, low cost, the distance estimations of compatible mobile phone
Method, the precision of ranging are much higher than the distance measuring method of conventional mobile phone, and such as bluetooth, Wi-Fi etc. is indoor locating system or outdoor high
Accuracy Positioning provides excellent basis.Using to timing tracking accuracy acoustical signal of less demanding as ranging medium,
The synchronous disadvantage for laying trouble of traditional wire connection is avoided, also avoids passing as the method for synchronization by Beidou time service simultaneously
Reached in a manner of decentralization in system wireless synchronization using additional synchronization node bring increased costs and unstability
The synchronization accuracy met the requirements makes whole system have higher robustness.For the present invention using acoustical signal as tacldng medium, compatibility is general
Logical microphone and loudspeaker, can be to be realized with a low cost higher range accuracy.
Detailed description of the invention
Fig. 1 is method flow schematic diagram of the invention；
Fig. 2 is the schematic diagram of beaconing nodes of the invention；
Fig. 3 is the schematic diagram of label node of the invention；
Fig. 4 is outdoor range error accumulated probability density map of the invention；
Fig. 5 is indoor range error accumulated probability density map of the invention.
Specific embodiment
The present invention is described in further detail with reference to the accompanying drawings and examples.
First introduce system structure employed in the present embodiment and hardware component.Beaconing nodes use STM32F407 core
Piece is as microprocessor chip, using WM8978 as the audio processing chip in loudspeaker module, using UM220-III conduct
Beidou timing module chip, using MP1584EN as power module, power module, loudspeaker module, beidou timing module are equal
It is connected with microprocessor, as shown in Figure 2.Label node uses STM32F407 chip as microprocessor chip, using WM8978
As the audio processing chip in microphone module, using UM220-III as beidou timing module chip, using MP1584EN
As power module, power module, microphone module, beidou timing module are equal to be connected with microprocessor, in addition, in order to handle
The range estimation arrived also uses CC2530Zigbee wireless communication module chip for being wirelessly connected with computer, such as
Shown in Fig. 3.
The implementation steps of method for estimating distance are described below:
Step 1: setting the identical PPS pulse period for the beidou timing module of all nodes, it is contemplated that acoustical signal exists
The factors such as decaying and reverberation in transmission process will be set as 0.2s the pulse period, can achieve the ranging period of 5Hz in this way.
Step 2: after beaconing nodes receive Beidou time service PPS pulse, triggering the external interrupt of processor, beaconing nodes are vertical
It carves and issues the high-frequency chirp signal through ovennodulation.The high-frequency chirp signal signal of the modulationref(m), table
Up to formula are as follows:
signalref(m)=cos (2 π m (f0+rate*m))
Wherein, m indicates that sampling number, rate are the slope of linear FM signal, initial frequency f0=18000Hz is terminated
Frequency f1=22000Hz, signal length T=0.427s.To ensure reaching higher bandwidth on the basis of not interfering human ear,
To enhance the resolution ratio of distance estimations.
Step 3: after label node receives Beidou time service PPS pulse, triggering the external interrupt of processor, label node note
Under record this moment local clock at the time of t0。
Step 4: label node constantly monitors acoustical signal, the acoustical signal that will be received, using the method for sliding window and with reference to letter
Number computing cross-correlation is normalized, judges whether to receive the modulated signal that beaconing nodes issue in step (3), if then carrying out
Next step；Otherwise, continue to monitor acoustical signal.
Step 5: after label node receives the modulated signal of beaconing nodes sending, determining that acoustical signal arrives using ratio threshold method
Thus the first diameter reached estimates the arrival time t of signal1.Then range estimation d=(t1-t0) c, wherein c is the velocity of sound.
The method of the sliding window is normalized computing cross-correlation with reference signal and includes the following steps:
Step A1: label node often receives n sampled point and is known as a frame, and it is (preceding to be classified as preceding fieldIt is a) with it is later half
Frame (afterIt is a), this frame data is denoted as signal2(m), the preceding field of the rear field of previous frame and this frame data is spliced and is denoted as
signal1(m), wherein m represents m-th of sampled point；
Step A2: by signal1(m) and signal2(m) respectively with reference signal signalref(m) it is normalized mutually
Close operation, calculation method are as follows:
Wherein, exp represents the exponent arithmetic using e the bottom of as；I is imaginary unit；S1It (k) is signal1(m) discrete Fu is carried out
In leaf transformation as a result, representing signal1(m) mutually it is worth in the width of k frequency component；S2It (k) is signal2(m) direct computation of DFT is carried out
Leaf transformation as a result, representing signal2(m) mutually it is worth in the width of k frequency component；SrefIt (k) is signalref(m) it carries out discrete
Fourier transformation as a result, representing signalref(m) mutually it is worth in the width of k frequency component；R1(τ) is signal1(m) and with reference to letter
Number signalref(m) normalized crosscorrelation is as a result, indicate difference τ moment signal1(m) and signalref(m) related journey
Degree；R2(τ) is signal2(m) with reference signal signalref(m) normalized crosscorrelation as a result, indicate difference the τ moment
signal2(m) and signalref(m) degree of correlation；
First three formula is actually discrete Fourier transform, directly can use quick Fu by the library function that ARM is provided
In leaf transformation algorithm calculated, can achieve than directly calculating faster arithmetic speed.
Step A3: by R1BeforeA point R2BeforeA point splices and is denoted as Corr, returns to step A1.
The ratio threshold method the following steps are included:
Step B1: the maximum value maxC and its position maxi of Corr are calculated, it may be assumed that
Max (Corr)=maxC=Corr (maxi)
When meeting the following conditions, then continue next step:
max(signal2) > thresholdsignal
Max (Corr) > thresholdR
Wherein, according to experiment, threshold is takensignal=0.2, thresholdR=50；
Step B2: from the preceding threshold of maxilengthA sampled point, i.e. maxi-thresholdlengthStart, backward
It searches, until finding first point j for meeting the following conditions:
Corr (j) > vRatioTh*max (Corr)
Wherein, according to experiment, threshold is takenlength=2048, vRatioTh=0.3；
Step C3: signal arrival timeWherein fs=48000Hz is the sample rate of voice signal.When signal is propagated
Prolong Δ t=t1-t0。
According to temperature conditions, velocity of sound c=340m/s, range estimation d=c* Δ t. are taken
Based on above parameter and arrangement, we are in spacious outdoor and the indoor environment of 10.5m*6.2m*2.9m
Range finding experiments are carried out, measurement distance measures 50 groups of data, measure true value with laser range finder, adjust the distance from 1~15m, every 1m
After estimated value and true value are compared and treated, obtained range error probability density distribution figure is as shown in Figure 4 and Figure 5.It can be with
See, in outdoor scene, 70% range error is within 3cm, and within 5cm, precision is much higher than 90% range error
The global position systems such as civilian GPS, Beidou.Scene indoors, 70% range error is within 10cm, 90% error
Within 45cm, precision is much higher than bluetooth, Wi-Fi etc..
Claims (6)
1. a kind of acoustical signal method for estimating distance based on Beidou time service, which is characterized in that method includes the following steps:
(1) the identical PPS pulse period is set by the beidou timing module of all nodes；
(2) after beaconing nodes receive Beidou time service PPS pulse, the external interrupt of processor is triggered, beaconing nodes issue at once
High-frequency chirp signal through ovennodulation；
(3) after label node receives Beidou time service PPS pulse, the external interrupt of processor is triggered, label node records this
T at the time of carving local clock0；
(4) label node constantly monitors acoustical signal, the acoustical signal that will be received, and noise is eliminated in progress high-pass filtering first, then
Computing cross-correlation is normalized using the method and reference signal of sliding window, judges whether to receive beaconing nodes in step (3) and sends out
Modulated signal out, if then carrying out next step；Otherwise, continue to monitor acoustical signal.
(5) it after label node receives the modulated signal that beaconing nodes issue, is determined using the ratio threshold method for eliminating multipath
The first diameter that acoustical signal reaches, thus estimates the arrival time t of signal1, then range estimation d=(t1-t0) c, wherein c be
The velocity of sound.
2. a kind of acoustical signal method for estimating distance based on Beidou time service according to claim 1, which is characterized in that described
The beaconing nodes mainly by loudspeaker module, first microprocessor, the first beidou timing module, the first power module group
At loudspeaker module, the first beidou timing module and the first power module are connected with first microprocessor.
3. a kind of acoustical signal method for estimating distance based on Beidou time service according to claim 2, which is characterized in that described
Label node mainly by microphone module, the second microprocessor, the second beidou timing module, second power supply module, channel radio
Interrogate module composition, microphone module, the second beidou timing module, wireless communication module and second power supply module with second micro- place
Device is managed to be connected.
4. a kind of acoustical signal method for estimating distance based on Beidou time service according to claim 1, which is characterized in that described
, the high-frequency chirp signal signal of the modulationref(m), expression formula are as follows:
signalref(m)=cos (2 π m (f0+rate*m))
Wherein, m indicates that sampling number, rate are the slope of linear FM signal, initial frequency f0With termination frequency f1It is all larger than
18000Hz, signal length T is in 0.04~0.05s.
5. a kind of acoustical signal method for estimating distance based on Beidou time service according to claim 4, which is characterized in that described
The method of sliding window computing cross-correlation be normalized with reference signal include the following steps:
(A1) label node often receives n sampled point and is known as a frame, and it is (preceding to be classified as preceding fieldIt is a) and rear field (after
It is a), this frame data is denoted as signal2(m), the preceding field of the rear field of previous frame and this frame data is spliced and is denoted as signal1
(m), wherein m represents m-th of sampled point；
(A2) by signal1(m) and signal2(m) respectively with reference signal signalref(m) computing cross-correlation is normalized,
Its calculation method are as follows:
Wherein, exp represents the exponent arithmetic using e the bottom of as；I is imaginary unit；S1It (k) is signal1(m) discrete fourier is carried out
Transformation as a result, representing signal1(m) mutually it is worth in the width of k frequency component；S2It (k) is signal2(m) discrete fourier change is carried out
It is changing as a result, representing signal2(m) mutually it is worth in the width of k frequency component；SrefIt (k) is signalref(m) direct computation of DFT is carried out
Leaf transformation as a result, representing signalref(m) mutually it is worth in the width of k frequency component；R1(τ) is signal1(m) and reference signal
signalref(m) normalized crosscorrelation is as a result, indicate difference τ moment signal1(m) and signalref(m) degree of correlation；
R2(τ) is signal2(m) with reference signal signalref(m) normalized crosscorrelation as a result, indicate difference the τ moment
signal2(m) and signalref(m) degree of correlation；
(A3) by R1BeforeA point R2BeforeA point splices and is denoted as Corr, returns to step (A1).
6. a kind of acoustical signal method for estimating distance based on Beidou time service according to claim 5, which is characterized in that described
Ratio threshold method the following steps are included:
(B1) the maximum value maxC and its position maxi of Corr are calculated, it may be assumed that
Max (Corr)=maxC=Corr (maxi)
When meeting the following conditions, then continue next step:
max(signal2) > thresholdsignal
Max (Corr) > thresholdR
Wherein, thresholdsignalIt is a constant related with speaker gain, thresholdRIt is sensitive with signal detection
Spend a relevant constant；
(B2) from the preceding threshold of maxilengthA sampled point, i.e. maxi-thresholdlengthStart, searches backward, directly
To finding first point j for meeting the following conditions:
Corr (j) > vRatioTh*max (Corr)
Wherein, thresholdlength, vRatioTh is two constants related with environment reverberation degree；
(B3) signal arrival timeWherein fs is the sample rate of voice signal, signal transmission delay Δ t=t1-t0。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910155577.2A CN109959921B (en) | 2019-02-27 | 2019-02-27 | Acoustic signal distance estimation method based on Beidou time service |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910155577.2A CN109959921B (en) | 2019-02-27 | 2019-02-27 | Acoustic signal distance estimation method based on Beidou time service |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109959921A true CN109959921A (en) | 2019-07-02 |
| CN109959921B CN109959921B (en) | 2021-03-26 |
Family
ID=67023953
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910155577.2A Active CN109959921B (en) | 2019-02-27 | 2019-02-27 | Acoustic signal distance estimation method based on Beidou time service |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109959921B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113721190A (en) * | 2021-10-28 | 2021-11-30 | 深圳市海豚科技创新有限公司 | Signal processing method and device for terminal, computer equipment and medium |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080228437A1 (en) * | 2005-03-31 | 2008-09-18 | Thyagaraju Damarla | Estimation of global position of a sensor node |
| CN106154230A (en) * | 2016-06-14 | 2016-11-23 | 浙江大学 | A kind of indoor orientation method of intelligent mobile terminal based on sound ranging |
| CN106251362A (en) * | 2016-07-15 | 2016-12-21 | 中国电子科技集团公司第二十八研究所 | A kind of sliding window method for tracking target based on fast correlation neighborhood characteristics point and system |
| CN109343332A (en) * | 2018-12-04 | 2019-02-15 | 北京七维航测科技股份有限公司 | Time dissemination system based on Big Dipper satellite signal |
-
2019
- 2019-02-27 CN CN201910155577.2A patent/CN109959921B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080228437A1 (en) * | 2005-03-31 | 2008-09-18 | Thyagaraju Damarla | Estimation of global position of a sensor node |
| CN106154230A (en) * | 2016-06-14 | 2016-11-23 | 浙江大学 | A kind of indoor orientation method of intelligent mobile terminal based on sound ranging |
| CN106251362A (en) * | 2016-07-15 | 2016-12-21 | 中国电子科技集团公司第二十八研究所 | A kind of sliding window method for tracking target based on fast correlation neighborhood characteristics point and system |
| CN109343332A (en) * | 2018-12-04 | 2019-02-15 | 北京七维航测科技股份有限公司 | Time dissemination system based on Big Dipper satellite signal |
Non-Patent Citations (1)
| Title |
|---|
| 林峰 等: "基于智能手机声信号的自标定室内定位系统", 《计算机研究与发展》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113721190A (en) * | 2021-10-28 | 2021-11-30 | 深圳市海豚科技创新有限公司 | Signal processing method and device for terminal, computer equipment and medium |
| CN113721190B (en) * | 2021-10-28 | 2022-02-15 | 深圳市海豚科技创新有限公司 | Signal processing method and device for terminal, computer equipment and medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109959921B (en) | 2021-03-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Höflinger et al. | Acoustic self-calibrating system for indoor smartphone tracking (assist) | |
| Chen et al. | Precise indoor positioning based on acoustic ranging in smartphone | |
| Mandal et al. | Beep: 3D indoor positioning using audible sound | |
| Lazik et al. | Ultrasonic time synchronization and ranging on smartphones | |
| CN106226738B (en) | Mobile device near field distance-measuring and positioning method based on acoustics | |
| Ens et al. | Acoustic Self‐Calibrating System for Indoor Smart Phone Tracking | |
| Chabbar et al. | Indoor localization using Wi-Fi method based on Fingerprinting Technique | |
| US8504077B2 (en) | System and method for monitoring and disseminating mobile device location information | |
| CN108226860B (en) | RSS (received signal strength) -based ultra-wideband mixed dimension positioning method and positioning system | |
| CN106656889B (en) | A kind of UWB indoor localization method based on CW with frequency modulation | |
| CN102455421B (en) | Sound positioning system and method without time synchronization | |
| US20150181381A1 (en) | Method and apparatus for time of flight fingerprint and geo-location | |
| CN104101863A (en) | Locating system based on intelligent mobile device and locating method | |
| Chen et al. | Smartphone-based indoor positioning technologies | |
| Hon et al. | Audio fingerprinting for multi-device self-localization | |
| US11808848B1 (en) | Method, system and terminal for wide-area acoustic indoor positioning based on RF enhancement | |
| CN108226912B (en) | Sparse network-based non-contact object perception positioning method and system | |
| CN109959921A (en) | A kind of acoustical signal method for estimating distance based on Beidou time service | |
| Thaljaoui et al. | Adopting dilution of precision for indoor localization | |
| CN112799014A (en) | Ultra-wideband positioning system and method based on ellipsoid intersection, wireless terminal and server | |
| Grgić et al. | An example of indoor positioning possibility using wifi network and mobile phone | |
| Zhang et al. | Acoustic localization system based on smartphone without time synchronization | |
| CN112558052A (en) | One-way TOA ranging system of smart mobile phone based on MEMS microphone sensor | |
| Zhao et al. | Optimal TOA localization for moving sensor in asymmetric network | |
| Vinyals et al. | Multimodal indoor localization: An audio-wireless-based approach |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |