CN207301310U - A kind of indoor positioning label node based on LF and UWB - Google Patents
A kind of indoor positioning label node based on LF and UWB Download PDFInfo
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- CN207301310U CN207301310U CN201721230946.2U CN201721230946U CN207301310U CN 207301310 U CN207301310 U CN 207301310U CN 201721230946 U CN201721230946 U CN 201721230946U CN 207301310 U CN207301310 U CN 207301310U
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Abstract
The utility model discloses a kind of indoor positioning label node based on LF and UWB, including MCU circuits, and the battery being connected respectively with MCU circuits and power converting circuit, UWB telecommunication circuits, LF telecommunication circuits and watchband fracture detection and warning circuit, MCU circuits realize that LF data transmit-receives, UWB data sendings, the watchband of whole label node are broken the management and control of detection and alarm.The utility model can solve the problems such as indoor high-density label node arrangement and high power consumption.
Description
Technical field
The utility model is related to the mobile tag node technical field of indoor locating system, it is more particularly to a kind of based on LF and
The indoor positioning label node of UWB.
Background technology
Since interior can not receive the satellite positioning signals such as GPS, ripe GPS positioning technology is not suitable for indoor positioning.Mesh
Preceding common indoor positioning technologies have infrared technology, ultrasonic technology, Bluetooth technology, WLAN etc., but these technologies
There are its it is intrinsic the defects of, such as infrared and ultrasonic technology cannot surmount wall, bluetooth and wireless local area network technology positioning accuracy
Low and unstable, these location technology power consumptions are also larger in addition, are difficult to realize the indoor positioning of low power consumption high-precision.
UWB (Ultra-Wide Band, ultra wide band) technologies are because of its bandwidth, speed height, strong antijamming capability, positioning accurate
Degree is high and applied in communication and positioning, but existing based on TWR (Two-Way Ranging, bidirectional ranging)
The UWB localization method traffics are big, and the mobile tag node number supported in an alignment system is generally less than 8, and mobile
Label node power consumption is larger, seriously limits its application range.
Label node installation is either worn on the mobile object for needing to position or personnel, label node and anchor node
Positioning and communicating main body is formed, anchor node is usually fixed, passes through fixed anchor nodes by certain communication technology and location algorithm
Known location coordinate come determine movement label node locus, so that it is determined that the position of mobile object or personnel.
In practical applications, in order to improve the communication distance of label node and anchor node, it is necessary to improve the UWB of label node
Transmission power.But when label node uses high-power transmitting UWB data, if the distance of label node and anchor node is too near,
Due to anchor node UWB reception amplifier saturations, anchor node does not receive the valid data that label node is sent on the contrary, occurs
" black under lamp " situation, it is therefore desirable to which dynamic adjusts the UWB transmission powers of label node, avoids the occurrence of " black under lamp ".
Utility model content
The utility model is directed to the problems such as indoor high-density label node and high power consumption, proposes that one kind is based on LF (Low
Frequency, low frequency) and UWB dual band communication mechanism TDOA (Time Difference of Arrival, reaching time-difference)
Indoor positioning label node.
The purpose of this utility model is realized by following technical solution：
A kind of indoor positioning label node based on LF and UWB, including MCU circuits 2, and be connected respectively with MCU circuits 2
Battery and power converting circuit 1, UWB telecommunication circuits 3, LF telecommunication circuits 4 and watchband fracture detection and warning circuit 5.
Preferably, battery includes polymer Li-ion rechargeable battery 101, voltage conversion circuit with power converting circuit 1
102nd, charging control circuit 103；Voltage conversion circuit 102 changes operating voltage of the voltage as circuit；Charging control circuit 103
Including process chip and peripheral circuit, Charge Management is carried out to lithium ion battery using the Charge Management pattern of constant current and constant pressure,
Charging control circuit realizes wired charging of the external power supply to lithium battery.
Further, battery further includes LF with power converting circuit 1 and receives amplitude limiter circuit 104；LF receives amplitude limiter circuit 104
Including oscillating circuit and rectification circuit, the resonance circuit of tag read-write equipment and label node is transferred to identical frequency of oscillation, is adopted
Label is transmitted its energy to by tag read-write equipment with the mode of resonance, oscillating circuit receives the signal that tag read-write equipment is sent and goes forward side by side
Row vibration produces alternating current, and the magnetic field signal of tag read-write equipment is converted into electric signal, and then alternating current is carried out by rectifying tube
Full-wave rectification, after filter capacitor and voltage-stabiliser tube amplitude limit, you can output stable DC fills for battery；LF receives limit
Width circuit 104 obtain energy do not influence LF communication under the premise of, also by charging control circuit unnecessary power storage in lithium
In battery, wireless charging is realized.
Preferably, MCU circuits 2 include microcontroller and associated peripheral circuits, and the EEPROM inside microcontroller, which is used to store, to be marked
Sign the node serial number and running parameter data of node；MCU circuits realize the LF data transmit-receives of whole label node, UWB data hair
Send, the management and control of watchband fracture detection and alarm.
Preferably, watchband fracture detection is designed with warning circuit 5 using microcontroller external interrupt mode, watchband fracture detection
Using the I/O pins of electric resistance partial pressure connection MCU, warning circuit is configured to the MCU pins of pull-up by a termination and the other end is grounded
Button composition, when pressing, the low and high level of corresponding MCU pins changes, so as to trigger MCU for watchband fracture or button
I/O event interrupts.
Preferably, UWB telecommunication circuits 3 include UWB power circuits 301, UWB transceivers and its peripheral circuit 302, Balun
Circuit 303 and UWB antenna circuits 304；UWB transceivers use DW1000, use SPI interface with MCU, DW1000 sends MCU
Data encapsulate and sent after UWB is modulated；UWB receivers and its peripheral circuit 302 are believed by SPI interface UWB_SPI, reset
Number line UWB_RESET and wake-up signal line UWB_WAKE is connected with MCU, and MCU passes through the SPI mouthfuls of configurations that can complete DW1000 parameters
And its transmission of UWB information, the replacement and wake-up of DW1000 can be realized by UWB_RESET and UWB_WAKE signal wires；Balun
The DW1000 differential signals exported are converted to single-ended signal by circuit 303 by two LC Compositional balances-imbalance converters；UWB
Antenna circuit 304 is using UWB ceramic antennas.
Preferably, LF telecommunication circuits 4 include MCP2030 and its peripheral circuit, realize and lead to the LF data of tag read-write equipment
Letter；Tag read-write equipment is anchor node or card sender, and card sender passes through the initialization parameter of LF communication configuration label nodes, anchor
Node changes the running parameter of label node by LF communication dynamics.
Preferably, LF telecommunication circuits work by the way of LF is interrupted and waken up, once detect from anchor node or
During the specific LF sequences that person's card sender is sent, the microcontroller waken up in LF telecommunication circuits and MCU circuits is received into LF data.
The utility model compared with prior art, has the following advantages that and beneficial effect：
(1) LF and UWB double frequency TDOA location technologies are used, the density of label node is improved, reduces label node
Power consumption.
(2) label node has wired and wireless two kinds of charging modes, and wired charging is exported by exterior 5V interfaces, radio
Can be from LF.In the case where ensureing LF normal communications, when the LF voltages that label node receives are beyond its receiver operation electricity
The part of pressure can charge lithium ion battery, realize that LF amplitude limits charge, which has the characteristics that trickle charge, extend
Lithium battery service life and cruising time.
(3) label node uses low power operation Mechanism Design, and interrupting wake-up mode by LF rising edges receives exterior LF
Data, comprehensive realized using time driving and event driven mode to anchor node are sent data, ensure that the real-time of positioning,
Keep low-power consumption at the same time.
Brief description of the drawings
Fig. 1 is embodiment label node overall construction drawing；
Fig. 2 is embodiment battery and power converting circuit schematic diagram；
Fig. 3 is embodiment UWB telecommunication circuit schematic diagrames；
Fig. 4 is embodiment LF communication WriteMode schematic diagrames；
Fig. 5 is embodiment software main program flow chart；
Fig. 6 is embodiment RTC interrupt routine flow charts.
Embodiment
The utility model is described in further detail with reference to embodiment and attached drawing, but the implementation of the utility model
Mode not limited to this.
Embodiment 1
A kind of indoor positioning label node based on LF and UWB, such as Fig. 1, this label node include battery and power conversion
Circuit 1, MCU circuits 2, UWB telecommunication circuits 3, LF telecommunication circuits 4 and watchband fracture detection and warning circuit 5.Using LF and UWB
Double frequency TDOA location technologies, LF are the downlink communication mode from anchor node to label node, and UWB is from label node to anchor node
Uplink communication, be particularly suitable for the positioning application of the asymmetric high density label node of two-way traffic.Anchor node passes through LF side
Formula dynamic configuration table node running parameter, label node send measurement data and working status by UWB.LF technologies and UWB skills
The combination of art reduces occupation rate of the label node downlink communication to UWB bandwidth, improves label node density and the reality of positioning
Shi Xing.
Referring to Fig. 2, battery includes polymer Li-ion rechargeable battery 101, voltage conversion circuit with power converting circuit 1
102nd, charging control circuit 103 and LF receive amplitude limiter circuit 104.Voltage conversion circuit 102 uses TI chip TPS62290, conversion
It is efficient up to 96%, be changed into the voltage of 3.3V, the operating voltage as circuits such as microcontrollers by chip DC/DC conversions.Fill
Electric control circuit 103 utilizes BQ2057 chips and simple periphery circuit design into compact charging control circuit, using constant current
Charge Management is carried out to lithium ion battery with the Charge Management pattern of constant pressure.LF receives amplitude limiter circuit 104 mainly by oscillating circuit
Formed with rectification circuit, by tag read-write equipment (tag read-write equipment can be anchor node or card reader) and the resonance of label node
Circuit is transferred to identical frequency of oscillation 125KHz or so, and label is transmitted its energy to by tag read-write equipment by the way of resonance,
Oscillating circuit, which receives the signal that tag read-write equipment is sent and carries out vibration, produces alternating current, and the magnetic field signal of tag read-write equipment is turned
Electric signal is turned to, then alternating current carries out full-wave rectification by rectifying tube, after filter capacitor and voltage-stabiliser tube amplitude limit, i.e.,
Exportable stable DC charges for battery.Charging control circuit realizes wired charging of the exterior 5V power supplys to lithium battery, together
When the energy that obtains of LF receiving circuits under the premise of LF communications are not influenced, also by charging control circuit unnecessary electricity after amplitude limit
It can be stored in lithium battery, realize wired and wireless dual charging.
MCU circuits 2 are made of microcontroller STM32L052C8T6 and associated peripheral circuits, the EEPROM of 2KB inside microcontroller
For storing the node serial number and running parameter data of label node.MCU circuits realize whole label node LF data transmit-receives,
UWB data sendings, the management and control of watchband fracture detection and alarm.
Watchband fracture detection is designed with warning circuit 5 using microcontroller external interrupt (EXTI) mode, watchband fracture detection
Using the I/O pins of electric resistance partial pressure connection MCU, warning circuit is configured to the MCU pins of pull-up by a termination and the other end is grounded
Button composition, when pressing, the low and high level of corresponding MCU pins changes, so as to trigger MCU for watchband fracture or button
I/O event interrupts, MCU complete respective handling.
Referring to Fig. 3, UWB telecommunication circuits 3 are by UWB power circuits 301, UWB transceivers and its peripheral circuit 302, Balun electricity
Road 303 and UWB antenna circuits 304 form.UWB transceivers use DW1000, use SPI interface with MCU, DW1000 sends out MCU
The data come are encapsulated as IEEE 802.15.4A forms and are sent after UWB is modulated.UWB power circuits 301 supply VDD (3.3V)
Electricity is converted to 1.8V by DC/DC voltage-releasing voltage stabilizers, powers for DW1000 kernels, and the I/O circuits of DW1000 directly use
3.3V power supply；UWB receivers and its peripheral circuit 302 pass through SPI interface UWB_SPI, reseting signal line UWB_RESET and wake-up
Signal wire UWB_WAKE is connected with MCU, and MCU can complete the configuration of DW1000 parameters and its transmission of UWB information by SPI mouthfuls,
The replacement and wake-up of DW1000 can be realized by UWB_RESET and UWB_WAKE signal wires.Balun circuits 303 are by two LC groups
Into balance-imbalance converter, the DW1000 differential signals exported are converted into single-ended signal；UWB antenna circuits 304 use
Be be operated in 3.2-7.2GHz frequency ranges have good gain UWB ceramic antennas ACA-107-T.
LF telecommunication circuits 4 are made of MCP2030 and its peripheral circuit, are realized and tag read-write equipment (anchor node or hair fastener
Device) LF data communications, LF data use 125kHz frequencies, and the initialization that card sender passes through LF communication configuration label nodes is joined
Number, anchor node change the running parameter of label node by LF communication dynamics.LF telecommunication circuits are by the way of LF is interrupted and waken up
Work, when detecting from the specific LF sequences that anchor node or card sender are sent, will wake up LF telecommunication circuits and
Microcontroller (STM32L052C8T6) in MCU circuits 2 receives LF data, and detects the RSSI of the LF signals of anchor node
(Received Signal Strength Indication, received signal strength indicator), can measure label node roughly accordingly
With the distance of anchor node, when label node has detected anchor node nearby in 2 meters, reduce UWB transmit powers, otherwise according to
Maximum transmission power is sent.When needing to carry out information exchange with card sender, controller is by sending " pincers are logical " and " pincers are disconnected " life
Order carries out clinching operation to aerial voltage, and the feedback of data is completed in a manner of loading and modulate.The data encoding of LF communications uses
Pulse-spacing coding, the coding of signal are realized by the MCU of anchor node or card sender by way of software.LF communication WriteModes
Data format in the bit stream of conventional LF communication data packets, increases the reference arteries and veins of " 1 " and " 0 " Double-number level referring to Fig. 4
Punching, in this, as the decoding foundation of follow-up bit stream, recipient's adaptive correction data accordingly, reduces the bit error rate.In order to the greatest extent
Current drain is likely to reduced, MCP2030 makes circuit obtain energy from magnetic field as far as possible using the design circuit of half power work
Amount, is powered by power supply in the case of unavoidable, reduces the power consumption of label.
Fig. 5 is the software main program flow chart of label node, when label node after the power is turned on, microcontroller start, enter
Step501, initialization I/O, buffer memory and peripheral hardware, includes the initialization of I/O of USART, SPI, button I/O and watchband etc.,
The configuration initialization of MCP2030 and DW1000 chips, and read EEPROM storage data or with default data initial work
Parameter, starts RTC timer interrupts afterwards, and enters main program cycle.Step502 according to the status data table deadline drive,
Event-driven processing, including the alternating of ADC samplings and type of data packet are sent；If receiving LF information, to communicate to LF into
Row processing is responded, while to detect the RSSI of anchor node LF signals, calculates the distance of label node and the anchor node.Then into
Enter Step503, check whether to need to send data；The Step507 configurations next RTC cycles are transferred to if it need not send data
Wakeup time, into low-power consumption Stop patterns, is otherwise transferred to Step504 packing UWB data packets, is sent subsequently into Step505
UWB data packets；Subsequently enter Step506 and judge whether total data is sent, if being then transferred to Step507, be not, turn
To Step505.When the interruption of RTC periodic awakenings or external interrupt (EXTI) occurs, label enters from Stop mode wakeups
Step511, is then transferred to each interrupt handling routines of Step512, more new state data table, and time driving and event-driven are carried out
Mark, afterwards into Step502 processing.
In order to save power consumption, the MCU of label node uses intermittent duty, and most of time is in sleep state
(Stop patterns), MCU software synthesises wake up the CPU in MCU using event-driven and time type of drive, after CPU wakes up
(Active patterns) completes corresponding event processing and cycle UWB data sending.UWB data are sent when there is event to trigger, then it is all
Phase triggering needs to wait for next cycle and retransmits UWB data, sends data and completes to enter sleep state.
Due to the mobility of label node, the distance between label node and anchor node are dynamic changes, in order to ensure
Reliable communication avoids anchor node from receiving the receiver saturation of UWB signal, it is necessary to the transmission power of dynamic adjustment label node.MCU
RSSI in being communicated according to LF come rough estimate label node with a distance from nearest anchor node, when label node has detected anchor section
Point nearby in 2 meters when, reduce UWB transmit powers, otherwise sent according to maximum transmission power.The calculation formula of distance such as (1)
Shown in formula：
In formula (1), d for label node with a distance from nearest anchor node, P1In be LF launch parties (anchor node) power, it is single
Position is dbm, and value launch party is transmitted to label node, letter when RSSI is label node receiver, transmitting data packet by data packet
Number intensity, reads, n is related with sender LF coil sizes and installation position, determines coil from MCP2030 chip internal registers
After size and mounting means, n is determined by testing, generally about 3.5.
Fig. 6 is RTC interrupt routine figures, is interrupted by RTC and enters Step601 progress soft timer timing, mainly including UWB
When sending cycle timer, battery capacity measurement period timer, watchband and key-press status sending cycle timer；It is laggard
Enter Step602 to carry out judging whether having time driving task, being driven for task of Step603 marks, Ran Houjin are entered if having
Enter Step604 to complete to interrupt return, be otherwise directly entered Step604 and realize that interruption returns.MCU uses the work of such interval
Mode, power consumption is reduced while real-time is ensured, when sending a UWB data using 1 second, the run time of MCU is with sleeping
Sleep the ratio between time about 1：2000 so that label node has extremely low power consumption.
Above-described embodiment is the preferable embodiment of the utility model, but the embodiment of the utility model and from above-mentioned
The limitation of embodiment, the change made under other any Spirit Essences and principle without departing from the utility model, modify, replace
Generation, combination, simplify, and should be equivalent substitute mode, is included within the scope of protection of the utility model.
Claims (8)
- A kind of 1. indoor positioning label node based on LF and UWB, it is characterised in that including MCU circuits, and respectively with MCU The battery that circuit is connected and power converting circuit, UWB telecommunication circuits, LF telecommunication circuits and watchband fracture detection and warning circuit, MCU circuits realize LF data transmit-receives, UWB data sendings, watchband fracture detection and the management and control alarmed of whole label node System.
- 2. label node according to claim 1, it is characterised in that battery and power converting circuit include polymer lithium from Sub- rechargeable battery, voltage conversion circuit, charging control circuit；Voltage conversion circuit changes operating voltage of the voltage as circuit； Charging control circuit includes process chip and peripheral circuit, using the Charge Management pattern of constant current and constant pressure to lithium ion battery into Row Charge Management, charging control circuit realize wired charging of the external power supply to lithium battery.
- 3. label node according to claim 2, it is characterised in that battery further includes LF with power converting circuit and receives limit Width circuit；LF, which receives amplitude limiter circuit, includes oscillating circuit and rectification circuit, by tag read-write equipment and the resonance circuit of label node Identical frequency of oscillation is transferred to, label is transmitted its energy to by tag read-write equipment by the way of resonance, oscillating circuit receives mark Sign the signal that reader is sent and carry out vibration and produce alternating current, the magnetic field signal of tag read-write equipment is converted into electric signal, so Alternating current carries out full-wave rectification by rectifying tube afterwards, after filter capacitor and voltage-stabiliser tube amplitude limit, you can export stable Direct current fills for battery；LF receives the energy of amplitude limiter circuit acquisition under the premise of LF communications are not influenced, also by charging control circuit Unnecessary power storage in lithium battery, wireless charging is realized.
- 4. label node according to claim 1, it is characterised in that MCU circuits include microcontroller and associated peripheral circuits, EEPROM inside microcontroller is used for the node serial number and running parameter data for storing label node.
- 5. label node according to claim 1, it is characterised in that watchband fracture detection uses microcontroller with warning circuit External interrupt mode designs, and using the I/O pins of electric resistance partial pressure connection MCU, warning circuit is terminated by one matches somebody with somebody for watchband fracture detection It is set to the MCU pins of pull-up and the button composition of other end ground connection, when watchband fracture or button are pressed, corresponding MCU pins Low and high level change, so as to trigger the I/O event interrupts of MCU.
- 6. label node according to claim 1, it is characterised in that UWB telecommunication circuits include UWB power circuits, UWB is received Send out device and its peripheral circuit, Balun circuits and UWB antenna circuits；UWB transceivers use DW1000, and SPI interface is used with MCU, DW1000 encapsulates the data that MCU is sent and is sent after UWB is modulated；UWB receivers and its peripheral circuit pass through SPI interface UWB_SPI, reseting signal line UWB_RESET and wake-up signal line UWB_WAKE are connected with MCU, and MCU can be completed by SPI mouthfuls The configuration of DW1000 parameters and its transmission of UWB information, can realize DW1000's by UWB_RESET and UWB_WAKE signal wires Reset and wake up；Balun circuits are changed the differential signal of DW1000 outputs by two LC Compositional balances-imbalance converters For single-ended signal；UWB antenna circuits are using UWB ceramic antennas.
- 7. label node according to claim 1, it is characterised in that LF telecommunication circuits include process chip and its periphery electricity Road, realizes the LF data communications with tag read-write equipment；Tag read-write equipment is anchor node or card sender, and card sender is communicated by LF The initialization parameter of label allocation node, anchor node change the running parameter of label node by LF communication dynamics.
- 8. label node according to claim 1, it is characterised in that LF telecommunication circuits using LF interrupt wake up by the way of into Row work, when detecting from the specific LF sequences that anchor node or card sender are sent, will wake up LF telecommunication circuits and MCU Circuit receives LF data.
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| CN201721230946.2U CN207301310U (en) | 2017-09-22 | 2017-09-22 | A kind of indoor positioning label node based on LF and UWB |
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| CN201721230946.2U CN207301310U (en) | 2017-09-22 | 2017-09-22 | A kind of indoor positioning label node based on LF and UWB |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112991582A (en) * | 2019-12-17 | 2021-06-18 | 罗伯特·博世有限公司 | Method and system for self-learning radio node bearing within a vehicle structure |
-
2017
- 2017-09-22 CN CN201721230946.2U patent/CN207301310U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112991582A (en) * | 2019-12-17 | 2021-06-18 | 罗伯特·博世有限公司 | Method and system for self-learning radio node bearing within a vehicle structure |
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Granted publication date: 20180501 Termination date: 20200922 |