CN105277936A - Range finding system based on mobile phone and method thereof - Google Patents
Range finding system based on mobile phone and method thereof Download PDFInfo
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- CN105277936A CN105277936A CN201410249124.3A CN201410249124A CN105277936A CN 105277936 A CN105277936 A CN 105277936A CN 201410249124 A CN201410249124 A CN 201410249124A CN 105277936 A CN105277936 A CN 105277936A
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Abstract
The invention provides a system for measuring distance between a first position and a second position and a method thereof. The system at least comprises (a) at least one mobile phone device and (b) at least one locator device. All the mobile phone devices of at least one mobile phone device are positioned at the first position and transmit optical synchronization signals and acoustic indicator signals. All the locator devices of at least one locator are positioned at the second position and receive the optical synchronization signals and the acoustic indicator signals. All the locator devices utilize at least two features of the acoustic indicator signals to calculate acoustic indicator arrival time of the received acoustic indicator signals. Acoustic-optical time difference is obtained with acoustic indicator arrival time of the received acoustic indicator signals acting as end time and optical synchronization time of the received optical synchronization signals acting as start time. Besides, the sequence of transmission of the optical synchronization signals and the acoustic indicator signals by the mobile phone devices and time difference of transmission of the optical synchronization signals and the acoustic indicator signals are considered, and distance is calculated with combination of air velocity of sound.
Description
Technical field
The present invention relates generally to the integrated built-in flash of multiplexing mobile phone and mobile phone outside speaker is found range, and in particular to a kind of system and method estimating the spacing of cell phone apparatus and positioner equipment.More particularly, the invention describes a kind of system, for determining the distance between cell phone apparatus to positioner equipment, only need loudspeaker and the built-in flash of multiplexing mobile phone, do not need to increase any external equipment to cell phone apparatus, the means of communication not needing other extra is synchronous to what realize between cell phone apparatus with positioner equipment.The present invention can be advantageously used for a part for following more general-purpose system, and this system is used for determining position (three dimensional space coordinate of cell phone apparatus present position) or for following the tracks of (determining position in real time).
Background technology
relevant technologies
The various ranging technologies of the range finding for mobile phone well known in the art, these technology are sometimes called as terminal ranging technology.
rSSI ranging technology
Market today adopts RSSI principle to position system (still measuring the distance of cell phone apparatus apart from each positioner equipment in essence), comprise ZigBee, WiFi etc.These systems calculate distance between cell phone apparatus and each positioner equipment according to the attenuation law of wireless signal, but because wireless environment complexity is high, easily be subject to again that personnel move, the change of environment layout's change and environmental parameter (temperature, humidity etc.) the thus affect die-away curve of wireless signal, make to adopt ZigBee, WiFi of RSSI ranging technology location (range finding) system to be difficult to the position of locating cellphone equipment accurately.
wireless location technology time of arrival (TOA)
TOA is a kind of wireless location technology, and TOA sends by mobile devices such as mobile phones the time (and according to velocity of sound at the uniform velocity constant in atmospheric envelope) that electromagnetic signal arrives base station by measuring, and calculates (distance) position.Synchronous requirement between this technical requirement handset device and base station is very high.And precision is not high, based on existing simultaneous techniques, within the positioning precision of TOA can be increased to 125m by the auxiliary positioning of building a station (range finding) of employing more than three.And this precision inside the subenvironments such as house almost without any application meaning.
for the system and method (NFER ranging technology) of near field electromagnetic positioning
(referenced patent publication number: CN1688895A) utilizes the corresponding relation of the electromagnetic signal phase differential that range transmitter (by locating) distance and the electric field component signal and magnetic-field component signal that receive the wireless signal that transmitter sends exist near field range and distance to obtain the distance of each steady arm (location receiver) range transmitter, the distance obtained in conjunction with more than three steady arm measurements calculates the 3 d space coordinate of transmitter, because what this location technology adopted is that the electromagnetic signal of 500KHZ ~ 1500KHz is located, mobile phone will send the electromagnetic signal then necessary external special transmitter module of this frequency range.
the patent easily obscured
a kind of utilize sound wave to carry out range observation mobile device and distance measurement method
(referenced patent publication number: CN1979088A) this patent adopts two mobile phones all possessing outside speaker and microphone staggered relatively, wherein main mobile phone sends the sound wave of certain frequency and starts timing, after this sound wave being detected from the microphone of mobile phone, another rate response sound wave is sent again from mobile phone, main mobile phone reads clocking value after receiving this response sound wave, and just can obtain the distance of its distance from mobile phone according to the velocity of sound.Although this patent and the present invention have employed the integrated outside speaker of mobile phone and produce acoustic signals, this patent realize principle and of the present invention to realize principle completely different.This patent merely utilizes sound wave to send and feedback sound wave detected, and determine distance according to the time difference of front and back.And way of the present invention sends optical synchronous signal by multiplexing embedded in mobile phone flashlamp, send sound mark signal by multiplexing loudspeaker.(and the speed of optical synchronous signal and sound mark Signal transmissions is completely different, in air, sound wave propagation velocity is 340m/s, the light velocity is 300000000m/s, in air, the chances are is 882353 times of the velocity of sound for the light velocity, so the delay of optical synchronous signal transmission almost can be considered) receive optical synchronous signal and sound mark signal by steady arm again, try to achieve distance according to both time difference and the air velocity of sound and complete measurement, steady arm not needs to feed back any acoustic signals to mobile phone again.
And the acoustic signals of this patent does not have some features that sound mark signal of the present invention provides, and lack antijamming capability that these features can cause the method for this patent to reach not as the present invention.Because be all adopt the loudspeaker of mobile phone to produce acoustic signals, so the sound wave of frequency that the sound wave behaviour ear produced can be heard, and people's living environment such as: chat, televisor, child are noisy, sound of the wind, electrical work noise etc. all may exist the component that can affect frequency of sound wave selected by range measurement system, triggering or measuring error thus interferometry leads to errors.And the noise in these environment is all complicated and changeable, there is sudden random feature.Even and if the feature of the sound mark signal that the present invention adopts makes sound mark signal of the present invention receive serious random noise disturbance, as long as long as but in the packet of all sound mark signals, have one can verify correct, the steady arm that just can reduce accurately receives the sound mark due in of sound mark signal, thus impregnablely can complete range observation.Only has the undesired signal (piping of lasting frequency stabilization) that there is a stabilized frequency in environment, the ability interferometry and the carrier frequency that this frequency complete harmony mark signal adopts overlaps substantially.This noise but this situation is not but worried, has following two reasons: the noise of the stabilized frequency that (1) people can not allow the medium-term and long-term existence of environment to hear, because can cause the discomfort of user.(2) mechanism of dodging that the present invention adopts can make range measurement system that the sound wave of other frequencies can be adopted as carrier signal, thus avoids this noise.
And the mode of the optical synchronous signal that the present invention adopts not only is synchronized the time reference of all steady arms, and imply the measurement request that steady arm is follow-up, that is, when not receiving the optical synchronous signal that cell phone apparatus sends, positioner equipment can not be found range by erroneous trigger.
a kind of distance-finding method based on mobile terminal
(referenced patent publication number: CN102175228A) this patent mainly make use of mobile phone camera and carries out taking pictures finding a view, and by finding a view before and after the displacement of fixing known length, solves similar right-angle triangle to solve the distance between mobile phone distance measured target.This patent and the present invention are without any place (except based on mobile phone) similar in principle, and adopt camera or and even embedded in mobile phone flashlamp be all only usual function in order to expose, the function sending optical synchronous signal and synchronous each steady arm do not born by embedded in mobile phone flashlamp, more do not utilize the outside speaker of mobile phone.
mobile terminal
What (referenced patent publication number: CN102854815A) the present invention adopted is realize range finding by mobile phone external reflection type ultrasonic range finder module, be by highly directive ultrasonic get to one there is certain rigid plane after time difference of being received of echo and the air velocity of sound try to achieve distance, realize principle, method be completely different from this patent.Due to ultrasonic, there is very strong directivity in addition, make this range measurement system except range finding, almost there is no other extension purposes.External ultrasonic module is needed to make this range measurement system almost be difficult to incorporate existing mobile phone mobile platform.
a kind of range measurement system based on mobile phone
(referenced patent publication number: CN103561141A) need external range finder module to complete range finding, and the present invention only multiplexing embedded in mobile phone flashlamp, outside speaker, do not need external any range finder module.
Known to inventor, a lot of prior art relies on to mobile phone external ultrasound measurement module, laser ranging module, or found range by the weak mode of radio signal RSSI signal intensity, depend in addition and adopt the mode of camera image process to realize range observation.In existing mobile phone ranging technology, employing cooperative multiplex built-in flash, outside speaker do not send the technology that optical synchronous signal harmony mark signal realizes finding range.
Summary of the invention
Key in summary of the invention herein and describe paragraph.
For measuring a system for the spacing of primary importance and the second place, described system comprises:
(a) at least one cell phone apparatus; Each cell phone apparatus of at least one cell phone apparatus described is positioned at described primary importance and launches optical synchronous signal harmony mark signal; And
(b) at least one positioner equipment; Each steady arm of at least one positioner equipment described is positioned at the described second place and receives described optical synchronous signal harmony mark signal; Described each positioner equipment utilizes at least two feature calculation of sound mark signal to go out the sound mark due in of the sound mark signal that it receives;
A kind of range measurement system of the spacing for measuring primary importance and the second place, wherein each positioner equipment is to receive the phototiming moment of optical synchronous signal for initial time, to receive the sound mark due in of sound mark signal for end time, obtain the flash-bang in sound mark due in and phototiming moment, and consider time difference of existing between the optical synchronous signal that described cell phone apparatus is launched and sound mark signal, calculate distance in conjunction with the air velocity of sound and realize described measurement.
For measuring a system for the spacing of primary importance and the second place, wherein said optical synchronous signal is produced by the built-in flash of multiplexing cell phone apparatus.
For measuring a system for the spacing of primary importance and the second place, wherein said optical synchronous signal may be used for each positioner equipment of (comprising reflection) in its effective transmission range synchronous.
For measuring a system for the distance between primary importance and the second place, it is the system unique identifier number that described cell phone apparatus distributes that wherein said optical synchronous signal at least contains this range measurement system.
For measuring a system for the spacing of primary importance and the second place, wherein said cell phone apparatus can temporarily forbid other handset emissions optical synchronous signals by wireless network before utilizing emitted light synchronizing signal, removes and forbid after it sends optical synchronous signal.
A kind of system of the spacing for measuring primary importance and the second place, wherein saidly can temporarily forbid other cell phone apparatus utilizing emitted light synchronizing signals by wireless network by each cell phone apparatus in equipment before utilizing emitted light synchronizing signal, and remove after it sends optical synchronous signal and forbid.
For measuring a range measurement system for the spacing of primary importance and the second place, at least two features of wherein said sound mark signal are:
(1) sound mark signal with packet be base unit continue and or a kind of mode transmit data, cell phone apparatus and positioner equipment adopt unified verification scheme come verification msg bag transmit after correctness;
(2) the packet inside that each verification is correct all comprises a value, this value is determined by cell phone apparatus and is inserted, the time difference sending the moment that its value and this packet send the sound mark signal that the moment is subordinate to this packet is proportional, and positioner equipment is according to this value and receive the moment comprising this Value Data bag and can calculate mark due in of speaking.
For measuring a range measurement system for the spacing of primary importance and the second place, wherein said cell phone apparatus is integrated with inertial sensor, initiates range operation when cell phone apparatus detects that fuselage rotates by inertial sensor.
For measuring a range measurement system for the spacing of primary importance and the second place, the characteristic of wherein said each positioner equipment monitoring of environmental noise in real time, and provide the reference avoiding described ambient noise interference for system.
For measuring a range measurement system for the spacing of primary importance and the second place, each positioner equipment of wherein said positioner equipment can the characteristic of testing environment noise in real time, and provides the reference avoiding described ambient noise interference for system.
A kind of range measurement system of the spacing for measuring primary importance and the second place, wherein said each positioner equipment comprises treating apparatus for realizing the collection of multi-frequency sound, the separation of each frequency, for identifying the sound mark signal of the combination of characteristic frequency, multi-frequency, CDMA coding.
For measuring a range measurement system for the spacing of primary importance and the second place, the coded sequence of the frequency of the characteristic frequency that the sound mark signal that wherein said each cell phone apparatus sends adopts, the array mode of multifrequency combination of frequency, CDMA coding and range measurement system are that the system unique identifier of handset allocation is number corresponding.
For measuring a method for the spacing of primary importance and the second place, described method comprises step:
A at the cell phone apparatus of described primary importance, () detects that fuselage rotates, and with this initiator range operation;
B () be two actions sequencing that can set and the time difference below:
(1) optical synchronous signal is sent by light modulation on the camera of multiplexing mobile phone; And
(2) sound mark signal is sent by the outside speaker of multiplexing mobile phone;
C () receives described optical synchronous signal in the described second place, and record is initial time by the phototiming moment that optical synchronous signal is synchronous;
D () receives described sound mark signal in the described second place, and verify the packet that the sound mark signal received comprises in real time;
(e) according to the time of reception of first correct packet of verification and extract from this packet with time difference length directly proportional value on time domain of the sound mark due in of sound mark signal, the sound mark due in calculating described sound mark signal is end time;
F () obtains flash-bang according to described end time and initial time, and consider sequencing and the time difference of step (b) two actions, calculates described distance, realize described measurement in conjunction with the air velocity of sound.
The object of this invention is to provide a kind of range measurement system based on mobile phone and method, optical synchronous signal can be sent by the built-in flash of multiplexing mobile phone, send sound mark signal by multiplexing mobile phone outside speaker, thus realize the location to mobile phone, and do not need, to mobile phone, any extra device is installed.
Further object of the present invention there is provided a kind of range measurement system based on mobile phone and method, realize carrying out synchronously each positioning equipment (receiver) by the built-in flash of multiplexing mobile phone, and do not need the transmission mechanism adopting other wired or wireless to realize the synchronous of each steady arm.
An object in addition of the present invention there is provided a kind of distance-finding method based on mobile phone, and sound mark signal that the method provides adopts special in the anti-interference mechanism of packet, thus greatly improves the antijamming capability of the system adopting this distance-finding method.
Other object of the present invention is to provide a kind of distance measuring equipment and method, and these apparatus and method can as a part for indoor locating system or positioning control system.
By instructions below and claims, and combine the accompanying drawing of diagram the preferred embodiments of the present invention, further object of the present invention and feature will be clearly, in the accompanying drawings, use similar label to mark similar element in the various figures.
Accompanying drawing explanation
Fig. 1 is the range measurement system schematic diagram based on mobile phone realized by multiplexing embedded in mobile phone flashlamp and outside speaker.
Fig. 2 is the range measurement system schematic diagram based on mobile phone realized by multiplexing embedded in mobile phone flashlamp and outside speaker.
Fig. 3 is the schematic diagram of the positioning system based on mobile phone according to fixed locator-cell phone structural allocation.
Fig. 4 is the process flow diagram that method of the present invention is described.
Embodiment
The present invention is described in detail, the preferred embodiments of the present invention shown in the drawings referring now to accompanying drawing is more complete.But the present invention should not be regarded as being limited to the embodiment proposed here, provide these embodiments to make the disclosure will be thoroughly with completely on the contrary, and scope of the present invention is conveyed to those skilled in the art completely.Carry throughout, similar label refers to similar element.
based on the system of mobile phone range finding
Convenience in order to discuss in embodiment subsequently all supposes that mobile phone sends optical synchronous signal harmony mark synchronizing signal simultaneously; but this should not be construed the situation that the present invention only protects optical synchronous signal and sound mark signal to send simultaneously, the present invention does not get rid of the situation that sound mark signal sends early than optical synchronous signal, optical synchronous signal sends early than sound mark signal.
Fig. 1 is the range measurement system schematic diagram based on mobile phone realized by multiplexing embedded in mobile phone flashlamp and outside speaker.
The range measurement system 100 based on mobile phone is illustrated in Fig. 1, citing does not limit as explanation, now suppose mobile phone 110 utilizing emitted light synchronizing signal 112 harmony mark signal 111 simultaneously, this range finding is realized by the mistiming (time difference is flash-bang Δ t105) of metering optical synchronous signal 112, sound mark the signal 111 successively time of arrival steady arm.(d106 is much larger than the distance between embedded in mobile phone flashlamp 131 and outside speaker 132) mobile phone 110 comprises built-in flash 131 and outside speaker 132.Built-in flash 131 utilizing emitted light synchronizing signal 112, outside speaker 132 transmitting sound mark signal 111.
Steady arm 120 receives optical synchronous signal 112 harmony mark signal 111.Steady arm 120 comprises first sensor 134, for receiving optical synchronous signal 112; And second sensor 133, for receiving sound mark signal 111.If the distance 106 between mobile phone 110 and steady arm 120 is, such as, be d.Built-in flash 131 is controlled and outside speaker 132 sends optical synchronous signal 112 harmony mark signal 111 simultaneously due to mobile phone 110, transport vehicle light wave propagation velocity due to optical synchronous signal 112 is far longer than the transport vehicle sound wave of sound mark signal 112, so the time that optical synchronous signal 112 transmission range d (106) consumes can be ignored.Therefore, the distance d=air velocity of sound × Δ t (105).Wherein flash-bang Δ t is by receiving the sound mark due in 104 of sound mark signal 111 with steady arm 120 for end time, receives with steady arm 120 the flash-bang Δ t that optical synchronous signal 112 moment obtains for initial time 103 subtracts each other.It is the system unique identifier number that mobile phone 110 distributes that the optical synchronous signal 101 received in Fig. 1 at least comprises range measurement system, the sound mark signal 102 received at least to comprise in a plurality of time domain continuously or or packet.
based on the basic structure of the range measurement system of mobile phone
Fig. 2 is the range measurement system schematic diagram based on mobile phone realized by multiplexing embedded in mobile phone flashlamp and outside speaker, illustrate the range measurement system 200 based on mobile phone in Fig. 2, this range finding successively arrives the mistiming realization in the moment of steady arm by metering optical synchronous signal 212, sound mark signal 211.Mobile phone 210 comprises embedded in mobile phone flashlamp 231 and outside speaker 232.
Steady arm 220 is positioned at the place of the distance d of mobile phone 210, and receives optical synchronous signal 212, sound mark signal 211.Steady arm comprises first sensor 234, first receiving circuit 222, second sensor 233, second receiving circuit 221, processor 260 and interfacing equipment 270.Processor 260 receives the first representative signal from the first receiving circuit 222 and receives the second representative signal from the second receiving circuit 221, with the system crystal oscillator clock of processor 260 for time reference identifies the first representation signal and the second representative signal, obtain and the first representative signal and the proportional third representative signal of the second representative signal step-out time, and utilize the distance d between third representative signal determination mobile phone 210 and steady arm 220.
In most of embodiment of the present invention, first sensor 234 in response to optical synchronous signal 212, and allows the first receiving circuit 222 to detect first signal proportional with optical synchronous signal 212.Exemplarily and not as restriction, the sensor in response to optical synchronous signal 212 comprises photodiode and phototriode.First receiving circuit 222 receives signal from first sensor, and produces first representative signal proportional with optical synchronous signal 212.Representative signal can be, such as, have the simulating signal of voltage, and this voltage directly and the amplitude proportional of optical synchronous signal 212.Or representative signal can be, pass on the digital signal belonging to the data of optical synchronous signal 212.First receiving circuit 222 can comprise that adjusting gear that wave filter, amplification, analog to digital conversion and design of hybrid circuits skilled practitioner understand usually.
In response to the second sensor 233 of sound mark signal 211, the second receiving circuit 221 is allowed to detect the secondary signal proportional with sound mark signal 211.Exemplarily and not as restriction, the sensor in response to sound mark signal 211 comprises conventional capacitive microphone and electret capacitor microphone.Second receiving circuit 221 detects the input signal coming from the second sensor 233, and produces second representative signal proportional with sound mark signal 211.Representational signal can be, such as simulating signal, its magnitude of voltage and the amplitude scaled versions of sound mark signal 211.Or representative signal can be, such as, pass on the digital signal belonging to the data of sound mark signal 211.Second receiving circuit 221 can comprise that adjusting gear that multi-channel filter, amplification, analog to digital conversion and design of hybrid circuits skilled practitioner understand usually.
Due to employing is the carrier of visible ray as optical synchronous signal 212, and visible light communication is easily subject to the interference of surround lighting.Illustrate as illustrating not as restriction, in some embodiments of the invention, first sensor 234 can adopt " interference elimination method of visible light communication system " (CN101232329A), and the visible ray effectively eliminated in environment disturbs.If optical synchronous signal 212 is sine wave signals, for the first receiving circuit 222, it is desirable to use very narrow bandpass filter, so that minimum noise maximize signal to noise ratio (S/N ratio).
There is certain directivity in the response of first sensor 234 and the first receiving circuit 222 pairs of optical synchronous signals 212, in order to better adapt to actual applied environment, first sensor 234 and the first receiving circuit 222 preferably guiding may transmit the optical synchronous signal 212 come substantially in response to each orientation in applied environment.In substituting embodiment, steady arm 220 can point to different monitoring directions with using the sensor of a plurality of first sensor 234 type, and the receiving circuit of a plurality of first receiving circuit 222 type processes the signal that each monitoring direction sensor receives, so as to realize to applied environment the monitoring of minimum blind angle.
It is the system unique identifier number that mobile phone 210 distributes that optical synchronous signal 212 at least contains range measurement system.Favourable like this steady arm 220 equipment is distinguished mobile phone 210 and is managed in the applied environment that there is a plurality of mobile phone 210.Citing is not conduct restriction as illustrating, in some embodiments of the invention, optical synchronous signal 212 is except comprising the alliance identification number of mobile phone 210 correspondence of launching this signal, and the geographic orientation that can also comprise the mobile phone detected by the integrated inertial sensor of mobile phone 210, electronic compass is inclined to towards, level.These information can also be used for secondary location Calculation in the positioning system realized further based on the inventive method, thus improve the precision of location.In other embodiments of the present invention, when user terminates based on the operation (movement posture that mobile phone 210 detects or touch-screen touch, sliding action input) of mobile phone 210, the command information that these identifying operations represent can join in optical synchronous signal 212 by mobile phone 210, achieves the transmission of order while realizing range finding.
Owing to adopting mobile phone 210 outside speaker 232 to produce sound mark signal 211, sound mark signal 211 is easily subject to the interference of other noise sources in environment.
Citing is not conduct restriction as illustrating, sound mark signal 211 generally all adopts the sinusoidal signal of the carrier wave of one group of fixed frequency in some embodiments of the invention, the filtering channel of one group of fixed frequency that the employing of the second receiving circuit 221 correspondence is same, such one group of filtering channel major function mainly contains two:
(1) neighbourhood noise do not overlapped with this channel frequence in environment is suppressed, get rid of environmental interference.
(2) arrive steady arm 220 at the sound mark signal 211 of a plurality of mobile phone 210 range operation simultaneously, or the signal when the first signal of both sound mark signal 211 conversions exists overlapping region in time domain for separating of both during arrival steady arm, thus realize steady arm 220 simultaneously to the range finding of a plurality of mobile phone 210.
The frequency channel that mobile phone 210 adopts is because range measurement system distributes to the system unique identifier difference of mobile phone 210 and different, and in the corresponding processor 260 in range measurement system or other core processing module, existence question blank is used for realizing frequency channel to the inquiry number to frequency channel of mobile phone 210 system unique identifier number, system unique identifier.The distribution of concrete system unique identifier number and frequency channel coupling are held consultation by range measurement system and each mobile phone 210 and are distributed and be recorded in this question blank.In the embodiment of the carrier wave acoustic signals of this employing one group of fixed frequency, what sound mark signal 211 adopted is that the means of amplitude modulation carry out signal transmission.Representation signal can be, such as simulating signal, and its amplitude is directly in direct ratio with the signal amplitude size that will transmit.Or representative signal can be, such as, pass on the digital signal with the signal correction that will transmit.But the type of the representative signal no matter transmitted in this embodiment, the amplitude-modulated signal that transmission is all is carrier reference with a fixed frequency.
Citing is not conduct restriction as illustrating, in other embodiment of the present invention, the carrier frequency of each mobile phone 210 is no longer the sine wave of single frequency, but single mobile phone 210 adopts a class frequency combination, is realized the transmission of serial digital signal by switching frequency in transmitting procedure.The combination of frequency that mobile phone 210 adopts distributes to the system unique identifier difference of mobile phone 210 and different because of range measurement system, and in the corresponding processor 260 in range measurement system or other core processing module, existence question blank realizes combination of frequency to the inquiry number to frequency channel of mobile phone 210 system unique identifier number, system unique identifier.The distribution of concrete system unique identifier number and the coupling of combination of frequency are held consultation by range measurement system and each mobile phone 210 and are recorded in this question blank.
Citing is not as illustrating as restriction, and in some embodiments also had of the present invention, the second receiving circuit of steady arm 210 does not adopt multichannel frequency-selecting filter, but the bandpass filter adopting a band logical wider.The mode that mobile phone 210 adopts CDMA to encode will transmit data packet coding in sound mark signal 211 with its system unique identifier be assigned to number corresponding coded sequence.Steady arm 220 first received with it corresponding optical synchronous signal 212 before receiving sound mark signal 211, obtains corresponding coded sequence carry out demodulation reduction to subsequently received sound mark signal 211 and obtain the packet that mobile phone 210 transmits via sound mark signal 211 according to the system unique identifier retrieval and inquisition table comprised in optical synchronous signal 212.
But no matter which kind of modulation system sound mark signal 211 adopts to realize the transmission of packet, the packet of its transmission all possesses following feature, even if these features can make steady arm 220 also accurately can define the sound mark due in of sound mark signal 211 when sound mark signal 211 is subject to severe jamming, these features are:
(1) sound mark signal 211 with packet be single complete unit continue and or a kind of mode transmit data, mobile phone 210 and steady arm 220 adopt unified verification scheme come verification msg bag transmit after correctness.
(2) the packet inside that each verification is correct all comprises a value, this value is determined by mobile phone 210 and is inserted, the time difference sending the moment that its value and this packet send the sound mark signal that the moment is subordinate to this packet is proportional, and steady arm 220 is according to this value and receive the moment comprising this Value Data bag and can calculate mark due in of speaking.
After the packet of sound mark signal 211 transmission adopts above-mentioned feature, as long as multiple packets that the sound mark signal 211 that steady arm 220 receives comprises have one transmit correct just can accurate anti-release sound mark due in, even if reach at this sound mark signal that moment second sensor receives flooded also that it doesn't matter completely by other noises.In other words, namely in the process of sound mark Signal transmissions, the noise that can interfere with sound mark signal contingently may be there is in applied environment, although infrequent noise continuation is not strong, but it extremely likely has influence on the sampling of steady arm 220 pairs of sound mark signal initial times, as long as even and if adopt sound mark signal 211 steady arm 220 of above-mentioned feature to be subject to strong interference even there is a packet can by correct transmission at sound mark due in, namely sound mark due in can be pushed away by counter accurately.
The characteristic of steady arm 220 monitoring of environmental noise in real time, and provide the reference avoiding ambient noise interference for system.Citing is not conduct restriction as illustrating, in one embodiment of the invention, the feature of steady arm 220 monitoring of environmental noise is the distribution of environmental noise power frequency spectrum, and environmentally the distribution suggestion range measurement system employing of noise power spectrum can avoid the frequency range that in noise power spectrum, noise power is concentrated.In another embodiment of the present invention, the feature of steady arm 220 monitoring of environmental noise is noise noises such as () the stirring clothes of such as washing machine cycles that exists of cycle in time domain, and avoids noise height crest segment transmission sound mark signal 211 according to the periodicity suggestion range measurement system of noise.In other embodiment of the present invention, steady arm 220 can monitor the multiple neighbourhood noise features that may affect the transmission of sound mark signal 211 comprising These characteristics simultaneously, thus more comprehensively provides the scheme avoiding ambient noise interference for range measurement system.
There is certain directivity in the response of the second sensor 233 and the second receiving circuit 221 pairs of sound mark signals 211, in order to better adapt to actual applied environment, the second sensor 233 and the second receiving circuit 221 preferably guiding respond the sound mark signal 211 that may receive with each orientation in applied environment substantially.In substituting embodiment, steady arm 220 uses the sensor of a plurality of first sensor 233 type to point to different monitoring directions, and the receiving circuit of a plurality of second receiving circuit 221 type processes the signal that each monitoring direction sensor receives, to realize the zero blind angle monitoring to applied environment.
Processor 260 obtains and the first representative signal of optical synchronous signal 212 amplitude scaled versions and second representative signal proportional with sound mark signal 211, and determines the flash-bang that the first and second representative signal arrive.Processor 260 can be regarded as, and (in order to illustrate not as restriction) possesses the arm processor of modulus sampling functions, it is sampled to the first and second representative signal, extract the moment that the first and second representative signal arrive waveform, and obtain the quantification flash-bang signal proportional with flash-bang according to the due in of the first and second representative signal, calculate distance in conjunction with the air velocity of sound.
In other examples, the first and second representative signal can be digitized packets, and processor 260 receives packet according to specific agreement, according to agreement verification mode checking data bag to mistake.Wherein the first signal packet adopt be the lightwave signal of higher modulation frequency as carrier, there is very high traffic rate.The time of individual data bag transmission is very of short duration, and generally general is about tens of microseconds.The error caused is negligible, so processor 260 directly determines the phototiming moment with the moment of the packet of the first representative signal received.
Wherein the carrier of the second representative signal and the sound mark signal 211 of people's ear hearing frequency domain are easily subject to the interference of neighbourhood noise, processor 260 needs the moment verifying correct packet according to first that receives from it and the value proportional with the time difference receiving this packet moment harmony mark due in extracted from this packet, and then anti-release sound mark due in accurately, obtain flash-bang according to sound mark due in and phototiming moment, calculate distance in conjunction with the air velocity of sound.
Interfacing equipment 270, in simple especially example, interfacing equipment 270 can be liquid crystal display, using the display as reading result d.The more complicated embodiment of data-interface can be, wireless or the wireline interface of connection handling device 260, the result of range finding will can be transferred to user apart from d with the form of the digital signal of video, audio frequency or other certain format agreements, or can as comprehensive tracking, determine position or positioning system a part pass on measure distance d to remote processor module, for further analysis.
fixed locator-cell phone structure
Fig. 3 is the schematic diagram of the positioning system based on mobile phone according to fixed locator-cell phone structural allocation.In Fig. 3, fixed locator-cell phone configuration positioning system 300 comprises mobile phone 310, and it launches the first optical synchronous signal 330, second optical synchronous signal 332, the 3rd optical synchronous signal 334, the 4th optical synchronous signal 336, first sound mark signal 331, second sound mark signal the 333, the 3rd sound mark signal 335, fourth sound mark signal 337.
Optical synchronous signal 330,332,334,336 adopts identical wavelength light wave as carrier and the light signal of modulation intelligence thereon.Optical synchronous signal 330,332,334,336 can be sent by mobile phone 310 flashlamp at different time order and functions, because mobile phone flashlight does not have very strong directivity, so the scattering of optical synchronous signal on four direction that optical synchronous signal 330,332,334,336 also can be flashlamp to be sent (and reflection).
Sound mark signal 331,333,335,337 be adopt with mobile phone 310 system in positioning system 300 be that frequency, the multi-frequency that its system unique identifier distributed number mates combines, sound mark signal that CDMA coded sequence and single-frequency amplitude modulation, multi-frequency switches, CDMA encodes mode send.Sound mark signal 331,333,335,337 can produce via the outside speaker of mobile phone 310 at different time order and functions, the acoustic signals produced due to mobile phone 310 loudspeaker does not have very strong directivity, so the scattering of a sound mark signal on four direction that sound mark signal 331,333,335,337 also can be outside speaker to be sent.
First fixed locator 320 receives the first optical synchronous signal 330 and first sound mark signal 331 and determines the first distance r1.Second fixed locator 321 receives the second optical synchronous signal 332 and second sound mark signal 333 and determines second distance r2.3rd fixed locator 322 receives the 3rd optical synchronous signal 334 and the 3rd sound mark signal 335 and determines the 3rd distance r3.4th fixed locator 323 receives the 4th optical synchronous signal 336 and fourth sound mark signal 337 and determines the 4th distance r4.
In order to the object explained instead of in order to limit, illustrate four fixed locators 320,321,322,323 in figure 3.Two steady arm generation positions are uncertain, and three steady arms can produce clear and definite position at bidimensional, or produce uncertain position in three-dimensional, and four locater produces clear and definite position in three-dimensional.
In a specific embodiment, because there is certain assembling distance in the built-in flash of mobile phone 310 and outside speaker, this distance is different and different from the concrete model of mobile phone 310, but positioning system 300 can carry out automatic input by the corresponding data of model of the typing of user's actual measurement or Internet existence.Positioning system 300 after completing the elementary location to mobile phone 310 (suppose sound mark signal, optical synchronous signal be all sent by a point) detect according to three axle electronic compasss of mobile phone and three axle inertial sensors mobile phone 310 reality towards and lateral attitude, the geographic orientation that combined positioning system is installed and height carry out according to the measurement result of each steady arm during elementary location (320,321,322,323) positioning precision that secondary computing obtains possessing more high precision reliability.
Data bus 340 is responsible for the data transmission between each equipment and is coordinated, data bus 340 can be the transmission system be all made up of wireless network in certain embodiments, the hybrid transmission system that data bus 340 can be made up of cable network and wireless network in some other embodiments.The wire communication form that wherein can adopt comprises: Erthnet, RSS422 serial bus, CAN, power line carrier etc.The wireless forms of communication that wherein can adopt comprises: the communication technology that the mobile phone terminal such as Wifi, bluetooth is conventional.Steady arm 320,321,322,323 in range measurement system can by data bus 340 transmitting range r1, r2, r3, r4 to central controller 350.Central controller 350 can collect distance r1, r2, r3, r4, calculates the position of mobile phone 310, and relays that positional information to any other equipment being connected to data bus 340.Consider that mobile phone 310 some smart mobile phones especially now have very strong arithmetic capability, so mobile phone 310 also can collect distance r1, r2, r3, r4, calculate the position of mobile phone 310, and relay that positional information to any equipment being connected to data bus 340.
Central controller 350 can coordinate frequency of operation or other running parameters of mobile phone 310 and steady arm 320,321,322,323.Such coordination can comprise: the frequency that work is applicable or the CDMA adopting applicable frequency or employing to be applicable to encode to avoid interference the range information obtaining or obtain optimum precision.Coordinate time or the dutycycle that also can comprise scheduling operation.The coordination compatibility that can also comprise between each mobile phone 310 coexists, the emissive power of signals security or other reasons controls.
Positioning system 300 especially suitably configures the Location Request of mobile phone 310 to meet user, and described Location Request may be some the location-based application in order to realize user in local environment.The scene of various application may be had, in order to the object illustrated instead of in order to limit, list several application below.
Such as, multiple fixed locator (such as, steady arm 320,321,322,323) can be disposed in the region of interest, and the people in this region wish to position its hand-held mobile phone (band built-in flash and outside speaker).Positioning system 300 is very suitable in indoor place for the position of mobile phone obtaining user and hold, and these places comprise the often movable indoor place of other people such as warehouse, freight house, hospital, market, subway, movie theatre, home environment.The present invention is also applicable to the application scenario of some open airs, the outdoor location that such as bus stop board, outdoor advertising, tourist attractions or other people are often movable, but should consider that inclement weather can cause certain interference to the stability of system.
In an illustrative examples, positioning system 300 can be deployed in the environment such as warehouse, hospital, market, subway, movie theatre and position the mobile phone 310 held user, and the architectural drawing layout of utilization and environments match or topomap navigate to user, thus user is made to find target location as early as possible.
In another illustrative examples, with reference to and in conjunction with the method for patent (CN102016949) " telepilot " and principle, this system can arranged at the environment such as office, home environment.User when utilizing mobile phone 310 to point to target object, the position of trigger location operations determination mobile phone 310, and the sensing target controlled plant determining user according to three axle inertial sensors integrated on mobile phone 310, three axle electronic compasss.And the duty of control objectives controlled plant (office equipment, household electrical appliance) is carried out by three axle inertial sensors integrated on mobile phone 310, three axle electronic compass identification subsequent actions.Citing as illustrate and not as restriction, one of them embodiment is, user in the intelligent home control system environment being integrated with this positioning system 300, at a certain position mobile phone 310 directed in orthogonal extendible electrically driven curtain.The position that positioning action determines mobile phone 310 initiated by mobile phone 310, and the integrated three axle inertial sensors of mobile phone 310, electronic compass identification mobile phone 310 sensing.Utilize that the position of mobile phone 310 is starting point, mobile phone 310 be oriented to directional structure vectorical structure ray, and try to achieve in the 3-dimensional digital Virtual Space that built when the intelligent home control system being integrated with positioning system 300 is installed to there is with this ray the equipment occured simultaneously be vertical extendible electrically driven curtain, thus choose vertical extendible electrically driven curtain to be target controlled plant.Subsequently, the amplitude that user is swung up and down by mobile phone 310 again controls vertical extendible electrically driven curtain folding and unfolding degree.
In other illustrative examples, with reference to and in conjunction with the method for patent (CN102016949) " telepilot " and principle, and original object is improved, extend further to from choosing the object of target device and then control objectives equipment: choose target device, and obtain information from target device.This for possess display now and can fully and user carry out mutual mobile phone 310 and have very large application potential.Citing is not as illustrating as restriction, and in some embodiments of the invention, the public information service Account Dept being integrated with this positioning system 300 is deployed in the environment such as subway, bus stop station board, cinema, market, outdoor billboard.User utilizes the position of mobile phone 310 and sensing to choose target object, and obtains and the information choosing target relevant from the information feed back equipment applied environment.Such as, user chooses outdoor billboard by mobile phone 310, and the more full and accurate information (such as commodity details, discount activity, shopping online link) relevant with ad content can be pushed to user by information feed back equipment corresponding to outdoor billboard in this environment.
based on the distance-finding method of mobile phone
Fig. 4 is the process flow diagram that method of the present invention is described.Method 400 for measuring the distance between primary importance and the second place starts at begin block 401.As block 402 method 400 sends optical synchronous signal, sound mark signal in primary importance by the built-in flash of multiplexing mobile phone, outside speaker.Method 400 receives optical synchronous signal, sound mark signal in the second place; Method 400, with specific order, is carried out continuously: (1) is initial time as obtained by the moment that optical synchronous signal is synchronous shown in by block 404; And (2) sound mark due in as the extraction sound mark signal shown in by block 405 is end time.As obtained flash-bang between the two shown in by block 406, as considered the order that optical synchronous signal, sound mark signal send in primary importance and the time difference shown in by block 407, and calculate the distance between primary importance and the second place in conjunction with the air velocity of sound.As method 400 shown in by block 408 terminates.
In addition, in the disclosure, any content all should not be construed as: get rid of range finding, location or positioning system and use extra information to refine the estimation of position.Other information used can comprise: exemplarily and not as restriction, the historical record of past position or change in location or come from the information in other sensor or source.Especially, the present invention is suitable as supplementing of GPS type tracker very much.The Function Extension of GPS Sort positioning system can not penetrate or not getable region to gps signal by the present invention.In the disclosure, any content all should not be construed as: get rid of the present invention and use for the prior art of following the tracks of, determining position or location together with any other.Similarly, the present invention can be supplemented by prior art systems, improves performance of the present invention with the position and region that can not produce separately reliable results in the present invention.
Just for illustrative purposes, provide embody rule, to help reader understanding, wherein the present invention is several by what prove in a lot of environment of swimming.Should also be appreciated that: although the drawings in detail provided and concrete example describe the preferred embodiments of the present invention, but they just for illustrative purposes, system and method of the present invention is not limited to disclosed fine detail and situation, and wherein can carry out various change and not deviate from the spirit of the present invention defined by appending claims.
Claims (12)
1., for measuring a system for the spacing of primary importance and the second place, described system comprises:
At least one cell phone apparatus; Each cell phone apparatus of at least one cell phone apparatus described is positioned at primary importance and launches optical synchronous signal harmony mark signal; And
At least one positioner equipment; At least one positioner equipment described is positioned at the described second place and receives described optical synchronous signal harmony mark signal; Described each positioner equipment utilizes at least two feature calculation of sound mark signal to go out the sound mark due in of the sound mark signal that it receives.
2. the system of the spacing for measuring primary importance and the second place according to claim 1, wherein each steady arm is to receive the phototiming moment of optical synchronous signal for initial time, to receive the sound mark due in of sound mark signal for end time, obtain the flash-bang in sound mark due in and phototiming moment, and consider time difference of existing between the optical synchronous signal that described cell phone apparatus is launched and sound mark signal, calculate distance in conjunction with the air velocity of sound and realize described measurement.
3. the system of the spacing for measuring primary importance and the second place according to claim 1, wherein said optical synchronous signal is produced by multiplexing cell phone apparatus built-in flash.
4. the system of the spacing for measuring primary importance and the second place according to claim 1, wherein said optical synchronous signal may be used for each positioner equipment of (comprising reflection) in its effective transmission range synchronous.
5. the system of the spacing for measuring primary importance and the second place according to claim 1, it is the system unique identifier number that described cell phone apparatus distributes that wherein said optical synchronous signal at least contains this range measurement system.
6. the system of the spacing for measuring primary importance and the second place according to claim 1, each cell phone apparatus in wherein said cell phone apparatus temporarily can forbid other cell phone apparatus utilizing emitted light synchronizing signals by wireless network before utilizing emitted light synchronizing signal, and removes after it sends optical synchronous signal and forbid.
7. the system of the spacing for measuring primary importance and the second place according to claim 1, at least two features of wherein said sound mark signal are:
Sound mark signal with packet be elementary cell continue and or a kind of mode transmit data, cell phone apparatus and positioner equipment adopt unified verification scheme come verification msg bag transmit after correctness;
The packet inside that each verification is correct all comprises a value, this value is determined by the cell phone apparatus sending this sound mark signal and is inserted, the time difference sending the moment that its value and this packet send the sound mark signal that the moment is subordinate to this packet is proportional, and positioner equipment can calculate according to this value and moment of receiving the packet comprising this value mark due in of speaking.
8. the range measurement system for measuring between primary importance and the second place according to claim 1, wherein said cell phone apparatus is integrated with inertial sensor, initiates range operation when cell phone apparatus detects that fuselage rotates by inertial sensor.
9. the range measurement system of the spacing for measuring primary importance and the second place according to claim 1, each positioner equipment of wherein said positioner equipment can the characteristic of testing environment noise in real time, and provides the reference avoiding described ambient noise interference for system.
10. the range measurement system of the spacing for measuring primary importance and the second place according to claim 1, wherein said each positioner equipment comprises treating apparatus for realizing the collection of multi-frequency sound, the separation of each frequency, for identifying the sound mark signal of characteristic frequency, multifrequency combination, CDMA coding.
The range measurement system of 11. spacings for measuring primary importance and the second place according to claim 1, the coded sequence of the characteristic frequency that the sound mark signal that each cell phone apparatus of wherein said cell phone apparatus sends adopts, multifrequency array mode, CDMA coding and range measurement system are that the system unique identifier of this handset allocation is number corresponding.
12. 1 kinds for measuring the method for the spacing of primary importance and the second place, described method comprises step:
Detect that fuselage rotates at the cell phone apparatus of described primary importance, and initiate range operation with this;
Two actions can be set sequencing and the time difference below:
Optical synchronous signal is sent by the built-in flash of multiplexing mobile phone; And
Sound mark signal is sent by the outside speaker of multiplexing mobile phone;
Receive described optical synchronous signal in the described second place, and record is initial time by the phototiming moment that optical synchronous signal is synchronous;
Receive described sound mark signal in the described second place, and in real time the packet that the sound mark signal received comprises is verified;
According to first time of reception verifying correct packet and the value proportional on time domain with the time difference length of the sound mark due in of sound mark signal extracted from this packet, the sound mark due in calculating described sound mark signal is end time;
Obtain flash-bang according to described end time and initial time, and consider sequencing and the time difference of step (b) two actions, calculate described distance in conjunction with the air velocity of sound, realize described measurement.
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| CN201410249124.3A CN105277936A (en) | 2014-06-08 | 2014-06-08 | Range finding system based on mobile phone and method thereof |
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| CN201410249124.3A CN105277936A (en) | 2014-06-08 | 2014-06-08 | Range finding system based on mobile phone and method thereof |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107526084A (en) * | 2016-06-22 | 2017-12-29 | 北京小米移动软件有限公司 | Distance measurement method and device |
| CN107561492A (en) * | 2017-08-22 | 2018-01-09 | 深圳市中孚能电气设备有限公司 | Localization method, device, server and storage medium |
| CN112558052A (en) * | 2020-12-07 | 2021-03-26 | 浙江德清知路导航研究院有限公司 | One-way TOA ranging system of smart mobile phone based on MEMS microphone sensor |
| CN112904324A (en) * | 2021-01-20 | 2021-06-04 | 北京小米移动软件有限公司 | Distance measuring method and device, terminal and storage medium |
| WO2023015556A1 (en) * | 2021-08-13 | 2023-02-16 | Oppo广东移动通信有限公司 | Distance determination method and apparatus, device and storage medium |
-
2014
- 2014-06-08 CN CN201410249124.3A patent/CN105277936A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107526084A (en) * | 2016-06-22 | 2017-12-29 | 北京小米移动软件有限公司 | Distance measurement method and device |
| CN107561492A (en) * | 2017-08-22 | 2018-01-09 | 深圳市中孚能电气设备有限公司 | Localization method, device, server and storage medium |
| CN107561492B (en) * | 2017-08-22 | 2019-11-19 | 深圳市中孚能电气设备有限公司 | Localization method, device, server and storage medium |
| CN112558052A (en) * | 2020-12-07 | 2021-03-26 | 浙江德清知路导航研究院有限公司 | One-way TOA ranging system of smart mobile phone based on MEMS microphone sensor |
| CN112904324A (en) * | 2021-01-20 | 2021-06-04 | 北京小米移动软件有限公司 | Distance measuring method and device, terminal and storage medium |
| CN112904324B (en) * | 2021-01-20 | 2024-04-09 | 北京小米移动软件有限公司 | Ranging method and device, terminal and storage medium |
| WO2023015556A1 (en) * | 2021-08-13 | 2023-02-16 | Oppo广东移动通信有限公司 | Distance determination method and apparatus, device and storage medium |
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