Archive for the ‘wireless’ Category

Israeli Drone Pilots Made Their Life-and-Death Choices Over Gaza, and how?

Saturday, November 24th, 2012

A Heron drone at the Palmahim air base in Israel in December of 2011. Photo: AP/Dan Balilty

The latest round of fighting between Israel and Hamas has settled into an uneasy ceasefire. But that won’t stop Israel’s drones from filling the skies over Gaza. In this 2009 story, written during the final days of the last Israel-Hamas  conflict, we took a look at how one drone pilot grappled with the moral choices that came with remotely spying, and ordering death, from above.

Life or Death choices will never been easier with judgement done through small screen. how these guys, manage doing these task properly or most importantly humanly. Guess, wired have this story covered here. Come on, take a look.

Courtesy: Wired.com

 

GPS Units Disable Themselves If They Go Faster Than 1,200 MPH

Saturday, August 13th, 2011

This is somehow a legacy border, but anyone out there have busted this fact? – GPS units disable themselves if they go faster than 1,200 mph and if they go above 60,000 feet…

GPS module

In GPS technology, the phrasing “COCOM Limits” is also used to refer to a limit placed to GPS tracking devices that should disable tracking when the device realizes itself to be moving faster than 1,000 knots (1,900 km/h; 1,200 mph) at an altitude higher than 60,000 feet (18,000 m).This was intended to avoid the use of GPS in intercontinental ballistic missile-like applications.

Some manufacturers apply this limit literally (disable when both limits are reached), other manufacturers disable tracking when a single limit is reached.

This limit is a frequent obstacle encountered, if not discussed, among hobbyists seeking to make high altitude balloons and of course would be a problem for homemade space programs.

courtesy: wikipedia

A GPS without GPS

Monday, July 11th, 2011

gsmlocalizerWow, that sounds weird. It’s actually a mini GSM-based localizer without any GPS devices attached. It’s an old device with the cheaper SimCom module SIM900.  Here is a complete working GSM localizator which is pretty cheap and small too.

As introduction, this system allows localization without directly using GPS technology; we are able to locate the desired object fairly precisely by using database availability together with the geographic position of the cells themselves. In some country the cell coordinates are not publicly known (i.e. in Italy). If so, where do we find such data? Through Google Maps… Google has been able to store billions of data regarding the location of its clients’ cell phones. But how does GSM localization work? The radio mobile network is made up of a number of adjacent radio cells, each of which is characterized by an identifier consisting of four data: a progressive number (Cell ID), a code related to the area in which that given cell is (LAC, or Local Area Code), the code of national network to which the cell belongs (MCC, an acronym for  Mobile Country Code), and finally the company code (MNC, or Mobile Network Code), which obviously identifies the phone company itself. For this reason, once a cell name and coordinates are known, and considering the maximum distance allowed between this cell and a phone  before the phone connects to a new cell, it is possible to find out, approximately, the most distant position of the phone itself. For example, if the maximum distance has been determined to be one mile, the cell phone can be within a one-mile radius. It can be deduced that the more cells are found in a given area, the more precisely one can determine where the phone is located (up to 200-350 feet). The idea of employing only a GSM device to build a remote localization system occurred to us when we realized that Google Maps Mobile, which had been conceived to allow smartphones equipped with a GPS receiver to use Google for satellite navigation, was extended to all cell phones, as long as they were able to support GPRS or UMTS data.  Naturally, this method allows but for a rough estimate: determining the precise position of the cell phone hinges on data regarding the coverage of a given cell which can only be provided by the Google server.

DataCell

The circuit

Compared to traditional localizers based on GPS, this device presents many advantages, primarily because it is lighter and less bulky, has a cost lesser and greater autonomy to exercise. This means that about one battery lithium ion, such as 1 Ah, our tracker can be in operation for several days (it all depends on the number of SMS that have to do). A locator based on cellular network may answare more immediately: the GPS receiver may take several minutes to determine its position. Our tracker works battery and thus can be brought on by people who may have the need to ask help or be tracked, but also placed on board motor vehicles (without installation) or simply introduced in goods in transit. To avoid unnecessarily draining the battery, the localizator provides its position via SMS, on requesto with a simple phone call. Among the functions implemented there is the SOS: By pressing the button the localizator sends a text message asking for help, containing the coordinates of position, the sending can be done to a maximum of eight thelephone numbers. When queried or with the autoreport function, sends an SMS with the localization.To know the location of remote device must send an SMS request cell is connected and sends a request (via GPRS) to Google’s site, the latter responds with the coordinates and the figure for the precision. Everything happens in seconds.

0908_Schema

Well, you can get hell of these stuff from link provided afterward. Design files and the firmware are included. A fun stuff to experiment with at your disposal. Mini GSM localizer without GPS at open-electronics.org.

All images are courtesy of open-electronics.org

Going cellular with your Arduino projects

Sunday, February 6th, 2011

going-cellular-with-arduino

It will be more interesting if we can get our projects connected, via wires or wirelessly. It can extend the functionality of the project itself. Here, i would like to share some useful stuff in order to add functionalities to your Arduino project.

You can add a huge measure of extensibility to a project by using a cellular connection. Anywhere the device can get service you can interact with it. In the past this has been a pretty deep slog through datasheets to get everything working, but this tutorial will show the basics of interacting with phone calls and text messages. It’s the 26th installment of what is becoming and mammoth Arduino series, and the first one in a set that works with the SM5100B cellular shield.

We love the words of warning at the top of the article which mention that a bit of bad code in your sketch could end up sending out a barrage of text messages, potentially costing you a bundle. But there’s plenty of details and if you follow along each step of the way we think you’ll come out fairly confident that you know what you’re doing. Just promise us that you won’t go out and steal SIM cards to use with your next project. Find part two of the tutorial here and keep your eyes open for future installments.

courtesy hackaday

Wirelessly Automate Your Home

Sunday, November 14th, 2010

home-automation-via-router.png

I’ve stumbled across this quite simple idea of home automation using Wifi. [Mrx23] combined OpenWRT, a microcontroller, and a set of RF controlled outlet switches to add automation to his plug-in devices. An RF remote that controls the switched outlets has been connected to an Arduino. The router communicates with the Arduino via a serial connection. And the router is controlled by a web interface which means you can use a smartphone or other web device to control the outlets.

The best thing about this system is the power that the router wields. Since it has an underlying Linux kernel you have the option of setting CRON jobs to turn lighting on and off, and group settings can be established to set up a room’s lighting level for watching movies, hosting guests, etc. Combine this with the fact that OpenWRT can use port forwarding for Internet control and the possibilities really start to open up.

Courtesy Mrx23 at Instructables.com

Wireless explanations

Friday, October 29th, 2010

Wireless-Internet-Security.jpg

Consumers today can choose from WHDI, wireless HD, WiDi, wireless USB and Wi-Fi Direct. Confused? Check out our guide to these emerging wireless streaming-media technologies.

WHDI

Wireless Home Digital Interface, or WHDI, was finalized in 2009 to give consumers a way to link the PC to the TV. Think of it as the wireless equivalent of HDMI. The technology has a latency of less than 1 millisecond, which means it’s good enough not just for watching movies but should also work well to stream games from your browser to the TV.

WHDI can stream 1080p video at up to 3 Gbps (gigabits per second). All you need is a wireless HDI dongle that can plug into your laptop and a little receiver that goes behind the TV. That set will cost about RM464.48 and will be available early next year.

Meanwhile, TV makers such as Sharp and LG are rolling out TVs with built-in support for WHDI standard.

Slowly, the WHDI consortium hopes to convince PC makers integrate WHDI chips into laptops, similar to the way Wi-Fi chips are built in today.

WirelessHD

While other wireless technologies focus on streaming content from the PC to the TV, WirelessHD targets the most common electronic eyesore in homes: the black HDMI cables that snake out from behind the TV towards the set-top box, PC or the DVD player.

If built into TV sets, WirelessHD can offer fast data transfers of up to 10 GBps to 28 Gbps. That makes it the fastest of the lot for point-to-point data transfer.

So far, TV makers such as Panasonic, LG and Vizio have said they will offer wireless-HD–enabled sets by the end of the year. (more…)

A brief about Smart Home

Thursday, October 14th, 2010

Smart Home is an intelligent and easy-to-use home management system that offers a richer set of home services by allowing appliances to interact with each other seamlessly. Capabilities of appliances are used as “Lego Kits” that can be mixed and matched to provide different home services for security, well-being, energy management and entertainment.

  • Built upon open communication UPnP standards.
  • “Lego Kits” to provide services to the home user.
  • A single user interface to manage appliances and customize home services.

Brief Introduction
The Smart Home project’s objective is to develop a reference implementation of a smart home system. This implementation utilities the Uninersal Plug n Play (UPnP) standard that has been adopted by major consumer electronic (CE) manufacturers as the emerging standard for device interoperability.

UPnP is an open standard (www.upnp.org) and its adoption by the CE industry consortium such as the Digital Living Network Alliance (DLNA) (www.dlna.org) augurs well for the end consumer. Home solutions (devices, system etc) will no longer be stovepipe (proprietary, single brand) in nature, as an open standard will ensure a common playing field and consumers will be free to choose amongst the various brand offerings.

Motivation
The following set of current problems/opportunities form the basis of the motivation underlying this project.

  • Devices are standalone in nature and typically do not communicate with other devices.
  • Due to the above (1), devices cannot cooperate/collaborate to jointly provide a richer set of services to the consumer.
  • Devices are difficult to setup and configure.
  • Even if (3) was made simple, it is difficult to pair devices and provision services.
  • Home networks are becoming more pervasive. Such networks are not just confined to ICT equipments (computers, printers, access point etc). Typical home devices/equipment such as lamps, stereo set, television etc will be part of the home network.

TeenyChron: A Linux-based GPS-synched NTP server

Sunday, September 26th, 2010

tinychron.jpg

The genesis of this clock stems from one of my other hobbies, Ham Radio. I wanted a reasonably accurate clock that would display both local and UTC time on a large LED display. Everything I could find missed the mark by at least one feature. So I set out to design a clock with the above features, and also with the additional feature of being a stratum one NTP time Server, that is synchronized to a GPS’s pulse per second (PPS) signal.

At the heart of the system I am using a small single board computer based upon an ARM processor running Linux. I actually purchased the board in 2006 for another undertaking that is still in my long list of projects. The TS-7400 Computer-on-Module is built and sold by Technologic Systems. In the configuration I bought the SBC I paid $155 for a single unit. Mine has 64MB of RAM, 32MB of Flash, a battery backed up real time clock (RTC), and runs a 200Mhz ARM processor. I’ve configured the board to boot and mount a file system from a 2Gig SD card. I love this board! It runs a full version of Debian Linux. To date, every standard software package I’ve loaded complies and runs without any trouble.

courtesy of TeenyChron

Home automation, a buzz word?

Friday, September 17th, 2010

Doing my routine jobs at my workplace, I stumbled upon some articles regarding home automation. It’s an old stuff actually, but I’m sure it will be interesting to read. I’ll share it later with you guys. It’ll be a busy weekend gathering enough points for this issue. There are some criterias to be covered when talking about home automation:

  • efficient energy management
  • security and surveilance
  • news and entertainment
  • drainage and watering monitoring system
  • alternative energy

If you have any other ideas, that some stuff are related to this issue. Just tweet it to me: @diblos

Modem used in an alarm system

Sunday, August 29th, 2010

ORP Systems

This alarm system senses motion and then alerts you by phone. And this fellow, [Oscar] had an old external modem sitting around and, with some wise hardware choices, he came up with a simple circuit to use it. First up is the PIC 16F628A chosen because it doesn’t require an external crystal. This connects with the modem via a DS275 RS232 transceiver because it requires no external parts for connection. The final portion of the puzzle is a PIR sensor that triggers a pin interrupt in the sleeping PIC, which then dials your number to alert you. It doesn’t look like anything happens other than your phone ringing, but that’s enough for a simple system. We’re glad to see how easy it was to use that modem… time to go hunting for one in dreaded junk trunk. Don’t miss the clip after the break.

What you can see in the video is: The modem is turned on and the pic configures it to disable command echo, change to return numeric responses and turn off the volume of the modem speaker. The user has 15 seconds to leave the room, then the pic waits a motion detection. When it is detected the pic dials a fixed phone number and the user will receive the alert.

The pic is programmed in CCS and the source code is included. Well, I bet it’ll be a great project to make. ^_^

Source ORP Systems