Interview Questions.

Q1. How Long Does A Node Operate On Battery Power?

Measurement node power intake depends on a spread of factors which include sampling c language, temperature, community topology, RF environment, and whether or not or now not the node conduct has been custom designed with the NI LabVIEW WSN Module.  National Instruments has determined that with a one-minute pattern c language at 25 C, usual battery lifetime is more than 2 years. 

Q2. What Wsn Products Are Available From Ni?

Consult the NI WSN Product and Configuration Guide to arise so far information at the unique node, gateway, and software program options to be had from NI.

Q3. What Is The Range Of The Wireless Communication?

The NI WSN Gateways and Measurement Nodes utilize a 2.4GHz IEEE 802.15.4 radio.  The Americas variations of these devices can hold reliable network communication at an out of doors variety of three hundred m with line of sight.  Exact device-to-device variety will vary based on geographic model, network site visitors, network topology, and RF surroundings.

Q4. How Do I Get Technical Support For Ni Wsn Devices?

You can take benefit of the NI WSN Setup and Services page to find tutorials, drivers, discussion forums and greater.

NI additionally offers good sized help alternatives thru ni.Com/guide. You can name, e-mail, or troubleshoot troubles on-line with NI engineers. In addition, ni.Com offers a wealth of sources for every purchaser – from users getting commenced with NI WSNs to professionals seeking out pointers from the designers.

Online sources include the subsequent:

Downloadable drivers and updates for NI-DAQmx and other dimension merchandise

More than 3,000 KnowledgeBase entries

Online product manuals (downloadable help files and PDFs)

More than 3,000 instance applications.

Q5. Which Ades Work With Wsn?

NI wi-fi sensor networks presently handiest paintings with NI LabVIEW model 8.6.1 and later.

Q6. What Are The Host Controller Options?

Each WSN gateway presents one-of-a-kind connectivity and host controller options.  With the NI 9792 Programmable WSN Gateway, no extra host controller is important, because the device is a LabVIEW Real-Time goal and might run independent of a host.  A LabVIEW Real-Time software may be deployed to the NI 9792 to mixture facts from size nodes and perform processing and analysis.  Even even though no host controller is necessary, you may still join the NI 9792 to different devices, together with a windows PC, database, or third birthday celebration WSN gateways.  The NI 9792 gives twin ethernet ports and an RS-232 serial port to hook up with those styles of devices.  Furthermore, the NI 9792 has a built-in web server so you can remotely visualize WSN dimension statistics in an internet browser.

The NI WSN-9791 Ethernet gateway, however, does require the use of a host controller.  The flexibility of ethernet lets in you to pick both a Windows or actual-time host controller. The Windows controller may be a PC, business controller, computer, or embedded tool strolling a Windows OS, along with embedded OSs along with XP Embedded, and LabVIEW for Windows. The real-time controller can be an NI CompactRIO or different programmable automation controller (PAC) jogging a actual-time OS and LabVIEW Real-Time.

Q7. How Do I Extract Measurement Data From The Wsn?

NI-WSN software program offers seamless LabVIEW integration so that you can fast and easily extract dimension records out of your WSN. After including aNI WSN gateway to a LabVIEW Project, the nodes configured with the gateway in MAX robotically populate within the LabVIEW Project, providing you with immediate get admission to to their I/O and properties. Simply drag and drop I/O variables from the LabVIEW Project to a LabVIEW Block Diagram for records extraction, evaluation, and presentation.

Q8. Can I Program The Node Itself?

With the LabVIEW Wireless Sensor Network Module you could use graphical programming to personalize node conduct by including intelligence to extend battery lifestyles, growth analog and digital input overall performance, and interface with custom sensors. You can also use the module to embed local intelligence, reply to virtual price exchange events, and modify behavior primarily based on measurement inputs.

The default behavior of an NI size node is to transmit every sample received to the gateway; however, this isn't always a demand for many applications and the LabVIEW WSN Module may be used to average samples over the years and provide threshold or dead-band logic, permitting you to increase battery life by means of transmitting simplest significant records. Additionally, acquisition rates on the node may be increased by now not incurring the overhead of transmitting each pattern after acquisition. Using the LabVIEW WSN Module, you may then perform processing and facts discount on the node. LabVIEW WSN packages are downloaded over the air to NI WSN dimension nodes, allowing seamless updates to deployed nodes.

Only the programmable versions of the size nodes can be focused by way of the LabVIEW WSN Module Pioneer.

Q9. What Is A Wireless Sensor Network?

A wi-fi sensor community consists of 3 primary additives:  gateways, nodes, and software program.  The NI WSN platform offers options in every of those classes so that you can personalize your WSN to fulfill the specific needs of your utility.

Wireless size structures can overcome energy and community infrastructure obstacles and meet new and formerly difficult utility challenges. They supply reduced prices and accelerated flexibility compared to standard stressed out measurement systems, and that they provide the ability to gain long-time period deployments with dependable, battery-powered devices. 

Q10. Can I Interface With Other Wsns?

NI gives LabVIEW drivers for third-party WSN nodes, together with those from Crossbow, Accsense, and Microstrain, so you can integrate NI WSN measurements with third-birthday celebration WSN measurements for your LabVIEW code. To communicate with these gadgets you need to use their gateway.  You can not use third-birthday party WSN (or other ZigBee) devices to speak at once with NI WSN gateways because of the proprietary NI WSN conversation protocol.

Q11. How Is The Network Configured?

With NI-WSN software program, that is covered with the NI WSN gateways (or downloaded right here), you may effortlessly configure your network in the Measurement & Automation Explorer (MAX) utility. MAX presents an intuitive user interface to feature and cast off dimension nodes and configure wi-fi settings. To set up your NI WSN, upload your gateway beneath Remote Systems in MAX and assign dimension nodes to a gateway via coming into the node serial range. Upon power-up or reset, the nodes routinely reconnect to the assigned gateway. 

You also can use MAX to view all the nodes for your WSN and their final verbal exchange time, battery reputation, and link satisfactory. In addition, MAX affords an interface to set the ZigBee verbal exchange channel, configure the Gateway IP deal with, wirelessly replace firmware at the dimension nodes, and configure a node to act as an stop tool or mesh router.

If you're the usage of the NI 9792 Programmable WSN Gateway, those operations can also be finished from an internet browser.

Q12. What Is The Difference Between Ni Wireless Compactdaq And Ni Wsn Devices?

NI Wireless CompactDAQ devices integrate IEEE 802.11b/g wireless or Ethernet verbal exchange, direct sensor connectivity, and the flexibility of NI-DAQmx software for a breadth of far flung dimension and manage alternatives. Externally powered, NI Wi-Fi DAQ devices can movement non-stop waveform information on every channel at greater than 50 kS/s and provide the best commercially to be had community security (WPA2 Enterprise). These gadgets are intended for shorter term, high throughput/streaming programs, in which you have a unmarried host related on your wi-fi client gadgets.

NI WSNs supply low-power measurement nodes that operate for up to 3 years on 4 AA batteries and can be deployed for lengthy-term, far flung operation. The wi-fi size nodes communicate with a significant gateway the usage of a protocol based totally on IEEE 802.15.Four to provide mesh routing skills that make bigger community distance and reliability. NI WSN systems help lower facts fees to hold strength, are without difficulty programmed the use of I/O variables.  These gadgets are intended for long run, slower pace programs in that you might be inquisitive about monitoring your assets or surroundings as soon as in line with minute, hour, or day.  NI WSN helps more than one information consumers per patron, which means multiple people can get entry to records from your WSN tracking machine any where, any time.

Q13. How Many Nodes Can Connect To A Single Gateway?

Creating a dependable community topology is a very essential factor in constructing your WSN machine.  You should cautiously take into account community topologies and facts verbal exchange paths whilst putting in a WSN gadget. 

To ensure maximum community reliability, National Instruments advocate that you adhere to the following criteria:

Without using router nodes, no extra than 8 quit nodes can join immediately to a unmarried gateway

Using router nodes, each gateway can hook up with a maximum of 36 overall nodes (routers + give up nodes mixed)

No extra than 8 end nodes can connect with a unmarried router node

Each cease node should be no greater than three hops faraway from the gateway

To obtain the greatest amount of cease nodes, NI indicates a topology consisting of one gateway, four router nodes, and 32 cease nodes (eight stop nodes for every router).   To acquire the finest coverage distance, NI suggests a topology consisting of 1 gateway, eight router nodes, and 28 give up nodes (seven stop nodes for each 2nd-tier router). 

The NI WSN protocol is built on a self-recovery network, which means that the community will routinely re-configure if necessary.  Because of this, it is essential to research all network possibilities and keep the eight:1 child-to-discern ratio for all community opportunities whilst designing your WSN topology.

Q14. Can I Use The Measurement Nodes Outdoors?

Yes. NI offers an IP65 out of doors enclosure for the WSN dimension nodes. The NI WSN-3291 out of doors enclosure has two I/O glands for routing power or sensor cables, and is shipped with 4 I/O gland inserts so you can custom-tailor the glands in your software. The enclosure has an external antenna that connects to the node through an internal SMB connector as well as an internal mounting plate with locking mechanism to cozy the node inner.

NI also gives an IP65 outside enclosure for the NI WSN-9791 Ethernet Gateway.  An out of doors enclosure for the NI 9792 Programmable WSN Gateway could be supplied quickly.

Q15. How Do I Know Which Products Are Certified For My Country?

View the Wireless Product Certifications report to determine which merchandise are certified to be used for your geographical place.

Q16. Will Ni Offer More Measurement Options In The Future?

Yes, NI plans to continue investment in WSN technology and offer a breadth of size node I/O options which can be like minded with the current product supplying.

Q17. What Are The Power Requirements For Ni Wsn Devices?

The dimension nodes can function on 4 1.5 V, number one AA alkaline or Lithium cells or an external deliver. Some NI WSN nodes guide battery lower back-up, that means the node will robotically switch over to battery power if external electricity is lost.  

When nodes are configured as routers, they have to stay on to send and acquire records throughout the community, and need to be powered with an outside supply. 

You can use sources other than wall electricity, such as sun or vibration electricity harvesting, to offer outside energy.

The WSN-9791 and NI 9792 gateways calls for an outside 9 to 30 V energy supply.

Q18. Which Network Protocol Does The Ni Wsn Devices Use?

The proprietary NI WSN protocol is primarily based on IEEE 802.15.4 and ZigBee era. The IEEE 802.15.Four conversation trendy defines the Physical and Medium Access Control layers inside the networking version, offering conversation in 3 frequency bands consisting of the 2.4 GHz ISM band. ZigBee builds at the 802.15.Four widespread with the community and application layers, presenting features including device coordination, reliability thru mesh networking topologies, and the capability to create person-defined profiles that permit for customization and flexibility inside the protocol. NI-WSN sits on top of the ZigBee layer and closes the protocol to third-celebration devices, ensuring network and information reliability.

Q19. What Warranty Is Provided With Ni Wsn Devices?

All NI WSN gadgets have a one-12 months guarantee that covers defects in workmanship and material from the date of product shipment. Extended assurance alternatives are to be had that let you restoration your preservation costs over two or greater years.

Q20. How Fast Can I Acquire Using Ni Wsn Devices?

Using default firmware/device personality, wherein inputs are sampled and right now transmitted to the gateway, the size nodes can pattern at the order of 30-60 samples per minute.  This price is consumer-described and may be programatically assigned in NI LabVIEW.

Using the programmable nodes and the LabVIEW WSN Module, you could pattern quicker regionally and keep or procedure the facts for transmission at a later time.  Because of this, you can sample quicker than the default costs. View the LabVIEW WSN Benchmarks document for facts on sampling quicker with NI WSN dimension nodes.

Q21. What Are The Features Of These Products?

The measurement nodes each provide four analog input channels and two to four virtual channels that you could configure on a per-channel foundation for enter, sinking output, or sourcing output. Four AA alkaline or lithium batteries can deliver up to a 3-year node lifetime. The size nodes supply -forty to 70 °C temperature ranges and industrial shock and vibration scores, and they communicate thru 2.4 GHz IEEE 802.15.4 radios that provide up to three hundred m outdoor range with line of sight. The nine to 30 V externally-powered gateways provides flexible connectivity to Windows or real-time OS controllers.