CN101489249A - Wireless sensor network test and measurement data collecting method and system thereof - Google Patents
Wireless sensor network test and measurement data collecting method and system thereof Download PDFInfo
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- CN101489249A CN101489249A CNA200910078782XA CN200910078782A CN101489249A CN 101489249 A CN101489249 A CN 101489249A CN A200910078782X A CNA200910078782X A CN A200910078782XA CN 200910078782 A CN200910078782 A CN 200910078782A CN 101489249 A CN101489249 A CN 101489249A
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Abstract
The present invention discloses a measured data collection method of wireless sensor network test and a system thereof, and belongs to the field of wireless sensor network. The method of the invention comprises the following steps: intercepting the inner signal of node from the bypass through a hardware collection module; and after preprocessing the inner signal, transmitting the inner signal to a processing center through a data transmission network. Thereby the test and measuring to the sensor network is realized under the precondition that the normal operation of wireless sensor network node is not effected. The system of the invention comprises a central server and at least one node test unit. The central service is connected with the node test unit through a transmission network. The node test unit comprises a node board, an adapting collecting board and a test board. The adapting collecting board is respectively connected with the node board through data wire or contact pin, and is connected with the test board through data wire. Compared with the prior art, the method and system of the invention have no interference to the normal operation of node and can collect actual and effective measured data of wireless sensor network. The measured data collection method and system of the invention are used for testing and measuring the network.
Description
Technical field
The present invention relates to a kind of wireless sensor network test and measurement data collecting method and system thereof, belong to the wireless sensor network field.
Background technology
Wireless sensor network (Wireless Sensor Networks, WSN are called for short sensor network) is formed by being deployed in microsensor nodes a large amount of in the monitored area, by a multihop self-organizing network of communication formation.Wireless sensor network will be the important component part of next generation network, the ability in the world of broaden people's perception greatly, be considered to produce one of technology of significant impact to 21 century, obtained the attention of departments such as countries in the world military affairs, industry, science.
The thermometrically technology of wireless sensor network to understanding network operation rule, is judged network failure or bottleneck, and optimizing network design planning has important directive significance.At present, multiple realization means are arranged, the SCALE that wherein typical scheme has Mote Works that Crossbow company proposes, MoteLab that Harvard University proposes and California, USA university (UCLA) to propose at the thermometrically technology of wireless sensor network.
The MoteWorks scheme that Crossbow company proposes as shown in Figure 1, it carries out the collection of test data based on the communication link of sensor network self, be that normal use data and test data all send the radio-frequency module (RF) of ordering node accordingly by node microprocessor (CPU), on the wireless sensor network link, transmit then, the user can the telemonitoring sensor network ruuning situation, show test results by text or graphics mode.The test target of MotoWorks is fixing the setting, comprises the dump energy, link-quality, transmission rate of topology of networks, node etc.Because test data has taken sensor network link and modal processor resource, will inevitably certain influence be arranged to self communicating by letter of sensing net, belong to and bother the formula test.
The MoteLab scheme of Harvard University exploitation as shown in Figure 2, it is made up of central server and sensor network, each sensor node in the network all is connected on the signal acquisition module, links to each other with central server by serial ports, and the connection Ethernet.Make the data of node to transmit like this, thereby realize test network state by radio communication device and serial ports and Ethernet multiple channel.The MoteLab scheme does not take the network communication of wireless sensor resource, but because test data by the CPU serial ports output of node module, has taken certain cpu resource, belongs to and bother the formula test.
A kind of method---SCALE that is specifically designed to the test of wireless sensor network link-quality that California, USA university (UCLA) proposes, its structure as shown in Figure 3.Each node of wireless sense network links to each other with computer by serial ports, make the packet of node can receive and dispatch by radio communication device on the one hand, can be transferred to computer by serial ports on the one hand, thereby its probability statistics rule is analyzed and studied to the situation of network data forwarding by comparing two results.But this method is the same with the shortcoming of above-mentioned two methods, and is bigger to the interference of other data on the link, and takies the resource of CPU, still belongs to bother the formula test.
All can't obtain the intra-node signal in the existing method, and intra-node needs extra operation to be used for the software module of test purpose, taking node communication link circuit resource and cpu resource in varying degrees, the work of node self is existed bother.
Summary of the invention
The object of the present invention is to provide a kind of wireless sensor network measurement data acquisition method and system thereof, for the processing center server provides wireless sensor network test and measurement data accurately.The present invention mainly is by the internal signal of hardware acquisition module from the bypass interception node, and these internal signals are carried out being transferred to processing center by data transmission network after the preliminary treatment, thereby under the prerequisite that does not influence wireless sensor network node work itself, realize thermometrically to sensor network.
Technical scheme of the present invention is:
A kind of wireless sensor network test and measurement data collecting method the steps include:
1) internal signal that transmits between acquisition node processor and this node radio frequency chip;
2) internal signal of gathering is converted into the transmission form that meets selected transmission network;
3) internal signal after the format conversion is sent to central server by selected transmission network and carry out network test and measurement.
Further, described modal processor or this node radio frequency chip are connected by data wire or contact pin with an adaptive collection plate, realize the collection of described internal signal.
In the described method, be converted into the transmission form that meets selected transmission network host-host protocol after described internal signal simplified preliminary treatment; Described internal signal comprises analog signal and digital signal.
The preprocess method of described digital signal is: when the internal digital signal produces a rising edge or a trailing edge, sample by a trigger event, and sampled signal is stored in the buffer queue.
The preprocess method of described analog signal is: gather current signal, and the last value of gathering of preservation, if current sampled value surpasses the preset threshold scope with the difference of last save value in the buffer queue, then it is saved in the buffer queue, proceed sampling; If current sampled value does not surpass preset threshold with the difference of last save value in the buffer queue, then in buffer queue, do not send into new value, and proceed sampling.
Comprise the sampling time in the described sampled signal, and the sampling time is saved in the described buffer queue with corresponding sampled value.
Described transmission network is an Ethernet; The host-host protocol of described transmission network is an ICP/IP protocol.
A kind of wireless sensor network test and measurement data collecting system, it comprises central server and at least one node test unit; Described central server is connected with described node test unit by transmission network; Described node test unit comprises node, adaptive collection plate and test board, and described adaptive collection plate is connected with described gusset plate, is connected with described test board by data wire by data wire or contact pin respectively.
Further, described test board comprises data processing module and data transmission module, and described data processing module is connected with described data transmission module by SPI (Serial Peripheral Interface communication protocol) data/address bus respectively; Described data processing module comprises signal processing module, gusset plate signals collecting interface, AD sampling module, and described signal processing module is connected, is connected with the AD sampling module by data wire with gusset plate signals collecting interface by data wire; The AD sampling module is connected with gusset plate signals collecting interface by data wire.
Described signal processing module comprises: data preprocessing module is used for the packing data of will gather; Data memory module is used for packing data is stored in the data fifo buffer queue; Communication module is used for the data that the data fifo buffer queue is stored are issued data transmission module; The processed clock signal module is used for the record data sampling time.
Described signal processing module is connected with the RS232 serial ports, is connected with SDRAM, is connected with charactron demonstration and buzz circuit by data wire by data wire by data wire respectively; Described transmission network is an Ethernet.
The present invention includes following components:
1, the collection of node signal
In the test and measurement data collecting method that this paper proposes, signals collecting is directly carried out bypass and is intercepted and catch as shown in Figure 4 on the internal signal between node cpu and the RF, be the signal of mutual communication between CPU and the RF, adaptive collection plate is all monitored with recipient's role and is caught.Thereby realized not having and bothered the real characteristic of data.This method neither takies the wireless data communication link of sensor network simultaneously, does not also take the resource of node cpu, belongs to not have to bother the formula test.
2, the data processing of node signal
The intra-node signal that adaptive collection plate listens to comprises digital signal and analog signal, because the data volume after the intra-node signal high-speed sampling is bigger, directly sends to data transmission module and can produce losing of data.The present invention proposes at different internal signals and adopt different preprocess methods:
The digital signal preprocess method is as shown in Figure 5: when the internal digital signal produces a rising edge or a trailing edge, come the announcement information acquisition module to sample by a trigger event, and the data and the sampling time that sample stored in the buffer queue, wait for the processing of data transmission module.Because the variation of digital level is not frequent, therefore only store sampling instant and the sampled value that a small amount of level changes moment, reduction that can be bigger data volume waiting for transmission.
Analog signal preliminary treatment way is as shown in Figure 6: gather current signal, and the last value of gathering of preservation, if current sampled value has surpassed the preset threshold scope with the difference of current save value, then send into a new value (also comprising the sampling time simultaneously) to data processing centre, and current save value is updated to current sampled value, proceeds sampling; If current sampled value does not surpass preset threshold with the difference of current save value, then in buffer queue, do not send into new value, and proceed sampling, as shown in Figure 6, first sampled value n1 of analog signal is saved in the buffer queue, simultaneously after the setting threshold scope, sampled point n2, n3, n4, the value of n5 and the difference of n1 are in the setting threshold scope, thereby be not saved, and the difference of sampled point n6 and current save value n1 surpasses the preset threshold scope, thereby the value of n6 is saved and is updated to currency, while n7, n8, n9 and the difference of upgrading the currency n6 that preserves the back are in setting range and be not saved, and in like manner the value of Cai Yang n10 is saved and the value of n11 is not saved.Because there is certain noise fluctuations in analog signal, by this method, can be at the prerequisite decline low data bulk that guarantees certain data precision.
3, the transfer of data of node signal
Data transmission module initiatively extract pretreated data from signal acquisition module, and with the data conversion extracted for being fit to the transmission form of transmission network, send to central server.Suggestion takes Ethernet as transmission network, takes ICP/IP protocol as Data Transport Protocol, also can adopt other network and agreement to carry out transfer of data.What whole data transmission module adopted is star-like message transmission structure, as shown in Figure 7.
4, central server
Central server is a multi-functional and high performance data analysis center, at first will collect node data information and relevant out of Memory that data processing module sends based on transmission network; And the form of all data messages with text stored; Analyze, resolve and add up the data message that is collected; Therefrom draw some network performance indexes (as packet loss, delay, network traffics, connectedness etc.), thereby realize the whole network performance is carried out real-time or non real-time monitoring and measured assessment.
The function that the central server real-time processing module comprises has data read, data parsing, understanding, time synchronized etc.; The function that the off-line analysis module comprises has remote logic analyzer, long-range ammeter, long-range power measurement etc.
Good effect of the present invention is:
Compared with prior art, the present invention is not having node self work under the prerequisite of bothering with transparent work, realize a kind of method of gathering, collect authentic and valid wireless sensor network test and measurement data, and carry out the thermometrically of sensor network based on the data of collecting based on hardware signal.
Description of drawings
Fig. 1, MoteWorks signals collecting schematic diagram;
Fig. 2, MoteLab signals collecting schematic diagram;
Fig. 3, SCALE signals collecting schematic diagram;
Fig. 4, the inventive method flow chart;
Fig. 5, digital signal samples method;
Fig. 6, the analog signal method of sampling;
Fig. 7, star-like message transmission structure;
Fig. 8, ZN-03 node signal to be measured;
Fig. 9, star-like message transmission structural representation;
Figure 10, single node system configuration;
Figure 11, test plate structure schematic diagram;
Figure 12, data preprocessing module structural representation;
Figure 13, node M AC receive the time-delay change curve.
Embodiment
1, sets up wireless sensor network
At first set up network to be measured with wireless-sensor network distribution type self-organizing characteristics with ZN-03, ZN series node is the wireless sensor network node that research and develop voluntarily in Institute of Software, Chinese Academy of Science wireless self-organization network research center, and the project organization and the characteristics of ZN-03 node are as follows:
(1) communication module adopts the radio transmitting and receiving chip CC2420 of the support IEEE 802.15.4 of chipcon company agreement, maximum 250k bps traffic rate, and the 0db communication distance can reach 100m.
(2) the super low-power consumption microprocessor chip MSP430F1611 of employing TI company.
(3) provide 40 abundant pin external interfaces, can connect programming plate or sensor board.
(4) support TinyOS operating system, make things convenient for software programming and programming.
(5) volume little (area 80mm*35mm, thickness 2mm)
ZN-03 node signal to be measured as shown in Figure 8, wherein ZN-03 node signal interface is the internal signal expansion slot that ZN series node carries, in the signaling interface 3～12nd, the control signal of CC2420,31～34th, the rs 232 serial interface signal of MSP430,35～40th, the JTAG signal of MSP430.
2, set up the wireless sensor network test macro
The wireless sensor network test macro is made up of following part, and title separately, quantity, abbreviation and description tabulation are as shown in table 1:
Table 1, system form title of part, quantity, abbreviation and description
| Title | Quantity | Abbreviation | Describe |
| Adaptive acquisition interface plate | Some | Adaptive collection plate (SC) | Signal acquisition module |
| The test core plate | Some | Test board (BTE) | The data processing module data transmission module |
| Ethernet | 1 | ||
| Central server | 1 | PC | Central server |
The wireless sensor network test macro is the message transmission structure of star-like characteristics, and system configuration as shown in Figure 9.
2.1, the single node system configuration
The structured flowchart of system as shown in figure 10, adaptive collection plate is passive circuit board, can customize different shapes and connected mode to adapt to different gusset plates.Adaptive collection plate is connected with gusset plate by data wire or contact pin, is responsible for the gusset plate signals collecting is come out, and delivers on the test board by data wire.Integrated data processing module and two parts of data transmission module on the test board.Node to be measured, adaptive collection plate and test board link together, and constitute a test cell.
2.2, data processing and transmission design
The data processing module of this system and transport module are integrated on the test board (BTE), and the node signal of receiving that is used to achieve a butt joint carries out preliminary treatment, and the signal after will handling sends to Ethernet.Test board mainly comprises a high performance ARM and a FPGA.Adopt arm processor to realize the flexibility of software processes, utilize FPGA to realize the flexibility that hardware signal is handled.The functional unit that test board comprises as shown in figure 11.The chip model of the main processing section of test board is as shown in table 2:
Table 2, the main processing section of test board chip model
| The module title | The chip model | Basic condition is described | |
| ARM | AT91SAM7X256 | The operation system provides certain memory space | |
| FPGA | EP2C8 | About 8K routing cell, 160kRAM, 208pin disciplines encapsulation, and enough IO are provided, | |
| The ethernet physical | DM9161 | 10/100M adaptive net card PHY chip | |
| SDRAM | HY57V641620 | For FPGA provides enough external memory spaces | |
| The AD sampling | TLC5510 | Being used for analog level measures | |
| The FPGA clock | 25M | Be used for intra-node signal high-speed sampling |
The effect of ARM mainly is to obtain data from the FPGA buffer queue, and data transaction is become to support that the form of TCP/IP is forwarded to central server.
The environment of FPGA operation is Quartus II 7.2, and programming language is Verilog HDL 2001.The effect of FPGA mainly is the acquisition process function that realizes data, as shown in figure 12, data preprocessing module is with the packing data of gathering, be stored in the data fifo buffer queue, accordingly when ARM will be when FPGA fetches data, data in the data fifo buffer queue are issued ARM by communication block with data, or the FPGA time is sent to ARM.
Embedded system among the ARM is based upon on FREERTOS V5.0.4 and the LWIP platform, can transmit data to central server based on ICP/IP protocol.
3, central server (PC) software design
Central server is a power PC, and the software of operation has: HCAT-Server, HCAT-Analyzer, HCAT-Player etc.
HCAT-Server data capture software, real-time display capture statistical information constantly, store the journal file that all data are specific format, and the data monitoring information by obtaining, the node power consumption of analysis wireless sensor network, packet loss relation, wireless channel conditions etc.
HCAT Analyzer signal analysis software by reading the data that HCAT-Server data capture software is preserved, parses each signal event and draws out the sequential chart of node signal.
HCAT-Player network state playback software is by reading the data that HCAT-Server data capture software is preserved, with the work activities historical events of each node in the animated playing network state.
The present invention simultaneously also can carry out the measurement of multiple network performance index, is that certain node M AC receives the time-delay change curve as Figure 13.This has shown that this method under the prerequisite that nothing is bothered, can support the thermometrically of rich and varied wireless sensor network state parameter.
Claims (10)
1. a wireless sensor network test and measurement data collecting method the steps include:
1) internal signal that transmits between acquisition node processor and this node radio frequency chip;
2) internal signal of gathering is converted into the transmission form that meets selected transmission network;
3) internal signal after the format conversion is sent to central server by selected transmission network and carry out network test and measurement.
2. the method for claim 1 is characterized in that described modal processor or this node radio frequency chip are connected by data wire or contact pin with an adaptive collection plate, realize the collection of described internal signal.
3. the method for claim 1 is converted into the transmission form that meets selected transmission network host-host protocol after it is characterized in that described internal signal simplified preliminary treatment; Described internal signal comprises analog signal and digital signal.
4. method as claimed in claim 3, the preprocess method that it is characterized in that described digital signal is: when the internal digital signal produces a rising edge or a trailing edge, sample by a trigger event, and sampled signal is stored in the buffer queue; The preprocess method of described analog signal is: gather current signal, and the last value of gathering of preservation, if current sampled value surpasses the preset threshold scope with the difference of last save value in the buffer queue, then it is saved in the buffer queue, proceed sampling; If current sampled value does not surpass preset threshold with the difference of last save value in the buffer queue, then in buffer queue, do not send into new value, and proceed sampling.
5. method as claimed in claim 4 is characterized in that comprising the sampling time in the described sampled signal, and the sampling time is saved in the described buffer queue with corresponding sampled value.
6. as claim 1 or 2 or 3 or 4 described methods, it is characterized in that described transmission network is an Ethernet; The host-host protocol of described transmission network is an ICP/IP protocol.
7. wireless sensor network test and measurement data collecting system, it comprises central server and at least one node test unit; Described central server is connected with described node test unit by transmission network; Described node test unit comprises node, adaptive collection plate and test board, and described adaptive collection plate is connected with described gusset plate, is connected with described test board by data wire by data wire or contact pin respectively.
8. system as claimed in claim 7 is characterized in that described test board comprises data processing module and data transmission module, and described data processing module is connected with described data transmission module by the SPI data/address bus respectively; Described data processing module comprises signal processing module, gusset plate signals collecting interface, AD sampling module, and described signal processing module is connected, is connected with the AD sampling module by data wire with gusset plate signals collecting interface by data wire; The AD sampling module is connected with gusset plate signals collecting interface by data wire.
9. system as claimed in claim 8 is characterized in that described signal processing module comprises: data preprocessing module is used for the packing data of will gather; Data memory module is used for packing data is stored in the data fifo buffer queue; Communication module is used for the data that the data fifo buffer queue is stored are issued data transmission module; The processed clock signal module is used for the record data sampling time.
10. system as claimed in claim 8 or 9 is characterized in that described signal processing module is connected with the RS232 serial ports, is connected with SDRAM, shows with charactron and buzz circuit is connected by data wire by data wire by data wire respectively; Described transmission network is an Ethernet.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101917736A (en) * | 2010-08-17 | 2010-12-15 | 中国科学院计算技术研究所 | Sensor network test bed system and test method thereof |
| CN102497336A (en) * | 2011-11-29 | 2012-06-13 | 北京华力创通科技股份有限公司 | Differential signal bypass collecting device and method |
| CN102625333A (en) * | 2011-11-18 | 2012-08-01 | 中国科学院上海微系统与信息技术研究所 | Recording device applied to wireless sensor network test and utilizing method thereof |
| CN108183949A (en) * | 2017-12-28 | 2018-06-19 | 北京理工大学 | A kind of self-adapting transmission control method of wireless sensor network test node |
| CN107864154B (en) * | 2017-12-12 | 2023-12-26 | 无锡维邦工业设备成套技术有限公司 | On-site signal acquisition method and device for information acquisition system |
-
2009
- 2009-03-03 CN CNA200910078782XA patent/CN101489249A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101917736A (en) * | 2010-08-17 | 2010-12-15 | 中国科学院计算技术研究所 | Sensor network test bed system and test method thereof |
| CN101917736B (en) * | 2010-08-17 | 2013-01-30 | 中国科学院计算技术研究所 | Sensor network test bed system and test method thereof |
| CN102625333A (en) * | 2011-11-18 | 2012-08-01 | 中国科学院上海微系统与信息技术研究所 | Recording device applied to wireless sensor network test and utilizing method thereof |
| CN102497336A (en) * | 2011-11-29 | 2012-06-13 | 北京华力创通科技股份有限公司 | Differential signal bypass collecting device and method |
| CN107864154B (en) * | 2017-12-12 | 2023-12-26 | 无锡维邦工业设备成套技术有限公司 | On-site signal acquisition method and device for information acquisition system |
| CN108183949A (en) * | 2017-12-28 | 2018-06-19 | 北京理工大学 | A kind of self-adapting transmission control method of wireless sensor network test node |
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