11/15/2013
Miracast is a new wireless display technology that is finally coming of age. Miracast allows teachers to magically display what is on a computer/device screen to a large screen HDTV or HDMI-capable projector WITHOUT any cables!
Miracast provides a solution to the dream of being able to walk about the room with a portable device completely untethered from any cables and having the screen magically appear on the big screen at the front of the room.
We have been successfully using miracast at the ITC to wirelessly project from Windows 8 tablets to the big screen HDTV for the past 10 months. For the most part miracast has been a reliable way (once setup) to share my Windows 8 Surface Pro screen wirelessly to the big screen. We have this also working on a NEC Projector (NP-M311W) that has an HDMI input for a miracast receiver.
There have been many products on the market in recent years that allow you to wirelessly display a computer screen but many have been prohibitively expensive to garner wide-spread adoption in the average classroom, that is starting to change with miracast.
To use miracast you need to have an approved and capable miracast device that meets certain technical requirements along with a miracast receiver and a big screen source with a HDMI input. This largely involves new graphics cards with appropriate drivers and firmware to support miracast along with the right combination of CPU and wireless adapter. Since miracast is so new we are going through some growing pains in making everything work seamlessly together but once setup and working you will find miracast worth the effort.
Miracast not only wirelessly displays the video to the big screen but also transmits the audio!
Below is a link to a YouTube Video of some of the experiments we have conducted at the ITC using the Netgear PTV3000 and the ScreenBeam 100 miracast receivers.
Over the past 10 months there have been many new developments with miracast technology, most notably the latest Windows 8.1 update has added built-in native support for miracast. This is great news for educators.
Although miracast has been under development for the past couple of years the first devices were certified in September of 2012. Miracast is just now becoming available to the general public and the number of devices on the market that support it is growing.
Because miracast is so new there are still many issues to work out in order for the technology to become reliable enough for the average classroom. To begin with you must have the right combination of hardware with compatible graphic cards and drivers to support miracast. Support for older devices is limited so be aware that you may need to buy new devices in order to use this new wireless display technology.
Microsoft just published a new Miracast Guide this week that explains the basics of using wireless display technology with the Windows 8.1 operating system.
Windows 8.1 on your big screen with Miracast Guide
The following is a quote about supported devices from the November 12th 2013 Windows Experience Blog:
“Wireless display works on new Windows 8.1 wireless PCs. This includes Surface 2 and Surface Pro 2, Nokia Lumia 2520, and Intel Atom Generation 3 (“Bay Trail”) and Intel Core Generation 4 (“Haswell”) systems. Some PC manufacturers have also added wireless display to some of their systems that originally shipped with Windows 8. This includes the Surface Pro and many systems based on Intel Core Generation 3 (“Ivy Bridge”) and Intel Wi-Fi. Be sure to check for updates from Windows Update and from your PC manufacturer, including driver updates listed as Optional, when determining whether your PC manufacturer has made wireless display available on your upgraded Windows 8 device.”
It clearly states that the first generation Surface Pro should be miracast capable with the Windows 8.1 update but we have had mixed results.
In our experience the ScreenBeam receiver has been working reliably with Windows 8.1 however the Netgear PTV3000 worked initially but has since become “undiscoverable” using the original Surface Pro. We are running the latest Windows 8.1 update and the latest 2.4.3 firmware for the Netgear PTV3000. We had previously been successful using the Netgear PTV3000 with Windows 8 but something has changed in Windows 8.1 that is causing issues. We will keep trouble-shooting in hopes that we can make the original Surface Pro work with the PTV3000.
This is where it can get messy. If you would like to learn more about the technical requirements and issues read on.
Before the Windows 8.1 update I had to use the ScreenBeam transmitter with the Surface Pro but since Windows 8.1 natively supports miracast I no longer need the transmitter. This frees up the only USB port on the Surface Pro so I am happy to give the transmitter up.
To learn more about the setup I used back in March 2013 please refer to this blog post:
Day 7 – How to Wirelessly Display (Mirror) the Surface Pro Windows 8 Tablet to a HDTV or HDMI Projector
One of the benefits of miracast is that it uses WiFi Direct (WiDi) meaning that you do not need an 802.11 wireless network in order for it to work. This has a couple of benefits over other technologies like AirPlay and Chromecast. First, you do not need to worry about bandwidth issues over a shared 802.11 wireless network. Second, connecting to school networks and dealing with subnets can be tricky so this is best to avoid if possible. Third, unlike Airplay you do not need to log into an AppleID account to use it. Also, other technologies like Chromecast can only display items within a Chrome browser tab, miracast allows whatever is displayed on the Windows 8.1 tablet to be displayed whether it be a Word document, OneNote, PowerPoint, browser window, music or video app, …. whatever, a huge plus for miracast.
If you use a device like the Surface Pro that has Pen input you can annotate on the fly while giving lessons.
So, to recap, miracast connects using a “pairing” process similar to how you connect a Bluetooth keyboard to a computer. Once the pairing is complete you will see the miracast-compatible device on the big screen HDTV! What you see and do on the tablet is displayed immediately on the big screen in real-time. There is a slight lag, especially when streaming HD video content but it is very usable. In my testing the physical range is about 50 to 75 feet, plenty of room to roam about the average sized classroom.
Many newer HDTVs and projectors are coming with miracast capability built in. If you have a newer HDTV that supports miracast you may not need the Netgear or ScreenBeam miracast receivers.
Here are more articles I have found helpful with trouble-shooting miracast issues:
Miracast is still a nascent technology, when you have the supported combination of hardware, drivers, and software it can work really well. However, if one component is not compatible then you will experience problems or in most cases miracast will not work at all.
Luckily, I have found a few “right” combinations and am enjoying the wireless display experience when I present in front of large groups of students. Being untethered from a projector and free to roam about the room is a liberating feeling for a teacher.
Keep on Learning,
Tom Grissom, Ph.D.
