For urban traffic simulator, we can use Sumo simulator with other simulators like Omnet++ or Matlab or Ns2/3.
I know Sumo can model mobility and other simulators coupled to Sumo for communication protocols or communication networks.
While it is possible to simulate VANET with just using Matlab.
What is the difference between them (SUMO and others or just using Matlab)?
How can we find which is better?
Thank you
It really depends on how much influence the traffic situation has to your scenario. If you are just interested in checking whether your protocol works even if two vehicles drive at 200 km/h in opposite directions but there is no interaction with other vehicles, you do not need SUMO. But if your scenarios involve jams or complex junctions and you want (more or less) realistic trajectories for interacting vehicles you are better off with a traffic simulation like SUMO (especially if you want to run on real world scenarios importing data from OpenStreetMap etc.).
Related
I'm trying to integrate omnet++ with a 3d robot simulator, and this is roughly what I'm picturing.
So There are a number of objects in the robot simulator, and they communicate with each other using 802.11 which will be simulated by omnet++. Each node in omnet++ corresponds to each object in the robot simulator, and an object's movement will be synchronized with the corresponding node in omnet++.
But since omnet++ is a discrete event simulator, I need to deal with the clock mismatch problem between omnet++ and the robot simulator.
I know omnet++ has cRealTimeScheduler class for synchronizing simulation clock to wall clock, but I'm not sure if this will do what I want.
I'm a noob when it comes to network simulation, so I want to know if this is even possible or not. Does using cRealTimeScheduler class take care of clock synchronization? or do I need to take a different tack? (a different scheduler, or even a different simulator?)
Any help will be greatly appreciated. Thank you.
If the robot simulator itself is running in real-time, then you are fine with the cRealTimeScheduler approach. cRealTimeScheduler will synchronize with the wall clock time. If the robot simulator is also running in real-time then the two will be implicitly synchronized, too.
If the robot simulator has its own simulation time (i.e. can run faster than real time) then you should create your own scheduler class that synchronizes the two simulation. This is called co-simulation where two simulation in tandem. Veins (sumo + omnet) is also doing this where Sumo (car traffic simulator) and omnet (network simulator) is working together.
What you are trying to achieve is possible, however I'm not familiar with the robot simulator part, but as long as the other simulator is also communicating with messages are discrete time points, and you can get the simulation time from the robot simulator, you should be fine.
I'm developing navigation system for my university as some kind of research activity. I'm using SVGKit to display floor plans. And now I need to provide user locationing service for navigation and tracking. So here's my questions:
1) Do I need some special hardware installed in university (Cisco MSE for example, or some cheaper analogues), or I can apply some software/technologies to our current hardware for server-side user location determining? If I do, what equipment do I need for it? I mean, it would be one unit for the whole university, or one per each floor, or what?
2)
Q: Why doesn't the Redpin iPhone client conform to the iPhone SDK
Agreement? A: Apple does not provide a public API to retrieve WiFi
data. In order to get the iPhone client working we had to use a
private API, which is disallowed by the iPhone SDK Agreement.
(c) http://redpin.org/faq.html Does it mean that RedPin is unacceptable in AppStore, so I can't use it?
3)Does Navizon I.T.S. requires some specific hardware equipment except standart routers?
Thank you all, maybe you can offer me better solutions, I hope. Thanks in advance.
Indoor positioning is a very vast field and many different solutions are available which all use a different combination of hardware/software. Some need no specific hardware to work, others need a very expensive infrastructure to be put in place. In the end, it all depends on the accuracy you are trying to achieve. Here are the most common solutions used, I ordered them by the type of technology used:
Wifi: two main techniques are used here, trilateration and fingerprinting. Both do not require specific hardware if your uni already has deployed access points (APs). Trilateration converts signal strength to distance and then intersect circles (almost exactly like GPS). In general this has poorish accuracy and you need to know the exact position of APs for it to work. Fingerprinting is a pattern matching technique where you first build a wireless map of the environment and then match the measurement against this map.
Bluetooth: same techniques as above can be used with Bluetooth nodes. Of course, there's less Bluetooth nodes than Wifi so you might need to deploy some extra nodes for it to be accurate enough. Same accuracy as Wifi (roughly 5 meters)
Dead reckoning: uses an accelerometer, gyroscope and compass to calculate the speed of heading of the user. Needs to be initialized and calibrated regularly by another absolute positioning technique. Subject to drift so accuracy degrades quickly over time. Upside is its very cheap, no extra hardware or initial survey phase are needed.
UWB: very accurate techniques based on time of flight measurements. Requires expensive hardware for both transmitter and receiver. You can achieve cm accuracy with this but it's probably not what you're after
This is still an field of research so it's not that easy to find something that just works. I suggest contacting the IT department of your university, if they run a Cisco system, I know some of them provide some sort of positioning capabilities but I don't have much details.
As for your iPhone question, any app that accesses the private API to access Wifi measurements will be rejected by the App store, so you won't be able to publish anything that relies on Wifi. You can still use it for research purpose though, you'll just have to figure out the code yourself as there's no official documentation (some unofficial doc is out there though)
Good luck!
I have a simulation project for wireless sensor networks. In the project I'm suppose to simulate two WSN protocols for performance and security. Protocols like ZigBEE, SPINS. Tinysec, LEDS, LiSIP. Any two from the list. The simulation is to be done in NS2. I don't know how and where to start? For simulation I need working codes for the protocols, how to I write the codes? I meant how should approach to write them or will I get it online.
Is this ever going to be possible? We have voice, image, data, etc..over ethernet. Is Touch over ethernet possible?
With the strides being made in Brain Computer Interfaces (e.g. controlling computers with nothing more than neural impulses), it's only logical to conclude that one day we'll be able to "reverse the stream" and have computers send the impulses to our brain that we can then interpret as touch, sight, hearing, taste, and smell. Who knows, it's quite possible that it has been done already and we are all dreamers in a digital world.
How's that for a mind frack?
Is there is a way to determine an iPhone's exact location (indoors, and to a distance of just a couple of feet) via use of radio/antenna's or some other infrastructure located around premises (i.e a hospital, shopping mall, school). Will appreciate any ideas/direction (technologies, research) as for how to overcome this limitation.
If you mean for an area you have control over (setting up a location network for a specific school/hospital) as opposed to generic location, you'd be able to triangulate your position based on wifi signal power for APs with known locations.
If you wanted it to be a generic solution, and you know there would be multiple APs in/around the buildings you wanted, you could triangulate all wifi signals while you have GPS outside the building, and then reference those locations when you lose gps accuracy. The first part is something that many wardriving applications already do.
Here's an article describing a commercial technology for this purpose in high-level detail: link
And here's a link to a SO page where people have started discussing possible methodologies: link
Use the GPS and hope that you got good coverage.
Other than this, you can deploy several wifi hotspots that can measure the signal strength for each packet and do a triangulation to calculate the iPhone position with regards to three or more of these hotspots based on the signal strength each of them measured.
A quick search for "signal triangulation" on the internet reveals a Wi-Fi Based Real-Time Location Tracking technology from Cisco. I have not used it, so I can't vouch for it; and I suspect it's rather expensive. There might be other solutions as well.
The alternative would be to buy several wifi routers or access points and flash them with your own version of the firmware. You can probably use OpenWRT or DD-WRT as a base for this.