WiFi & GPS

The WiFi stack gets an update with the new iPad courtesy of Broadcom's 65nm BCM4330, compared to the BCM4329 used in the previous two iPads. Both 2.4GHz and 5GHz operation are supported, although as I mentioned earlier the carrier-dependent personal hotspot is only available over 2.4GHz.

As with most smartphone/tablet designs the BCM4330 only supports a single spatial stream, for a maximum link speed of 72Mbps. Similar to the iPad 2, Apple hides the WiFi antenna behind the speaker grille at the bottom of the tablet. The cellular antennas (there are now two) are at the top of the tablet, behind the plastic RF window.

WiFi Performance Comparison
Distance from AP 3 feet 20 feet (Different Room) 50 feet (Different Room/Floor) 100 feet (Different Room)
ASUS TF Prime (2.4GHz) 26.9 Mbps 9.85 Mbps 13.5 Mbps 2.20 Mbps
Apple iPad 2 (2.4GHz) 35.1 Mbps 29.9 Mbps 26.9 Mbps 10.6 Mbps
Apple iPad 3 (2.4GHz) 35.1 Mbps 29.9 Mbps 27.9 Mbps 9.98 Mbps
Apple iPad 2 (5GHz) 36.7 Mbps 36.7 Mbps 36.7 Mbps 11.9 Mbps
Apple iPad 3 (5GHz) 36.7 Mbps 36.7 Mbps 36.7 Mbps 11.7 Mbps

With a similar WiFi stack and similar antenna placement, it's no surprise that I noticed very similar WiFi performance to the iPad 2.

The same goes for GPS performance between the new iPad and the iPad 2. Both devices were able to lock and track me driving around in a car with comparable accuracy from what I could tell.

Airplay Support with the new Apple TV

When paired with a second or third generation Apple TV, the iPad supports wireless display mirroring or content streaming to the iPad via AirPlay. In other words, if you have an Apple TV hooked up to your HDTV, you can use your HDTV as a large, mirrored, secondary display for your iPad—wirelessly. The only requirement is that you have a 2nd or 3rd generation Apple TV and that it's on the same network as your iPad. With those requirements met, enabling AirPlay mirroring is simple—just bring up the iOS task switcher, swipe left to right until you see the brightness/playback controls and tap the AirPlay icon.

Mirroring gives you exactly what you'd expect—a complete mirror of everything you see on the local iPad screen. All sounds are also sent over and come out via your TV's speakers—the local speaker remains silent.

The frame rate isn't as high on the remote display, but there's virtually no impact to the performance of the iPad itself. There's noticeable latency of course since the display output is transcoded as a video, sent over WiFi to the Apple TV, decoded and displayed on your TV via HDMI. I measured the AirPlay latency at ms, which is reasonable for browsing the web but too high for any real-time games. If you want to use the iPad to drive your HDTV for gaming you'll need to buy the optional HDMI output dongle.

While AirPlay mirroring on the iPad works at 720p, if you're playing a 1080p movie on the new iPad and you have a 3rd generation Apple TV, the video is also displayed in 1080p rather than downscaled to 720p.

Video playback is an interesting use case for AirPlay and the iPad. If you don't have mirroring enabled, you can actually start playing a movie on the iPad, have it stream to your TV via the Apple TV, and go about using your iPad as if nothing else was happening. Most apps will allow you to stream video in the background without interrupting, however some games (e.g. GTA 3, Infinity Blade 2) and some apps (e.g. iMovie) will insist on streaming their UI to your Apple TV instead.

Although iOS and the iPad don't do a great job of promoting multi-user experiences, using AirPlay to push video to a TV wirelessly is an exception. If you frequently load your iPad up with movies you can use it to keep others entertained while you either get work done or just goof around on your iPad at the same time. It's a great fit for families where people want to do two different things. If you do put a lot of movies on your iPhone/iPad, the 3rd generation Apple TV is probably a must buy for this reason alone.

Gaming Conclusion & Controller Support: An Android Advantage What's Next: 6th gen iPhone, Haswell & Windows 8
POST A COMMENT

232 Comments

View All Comments

  • seanleeforever - Thursday, March 29, 2012 - link

    Correction: YOU won't buy it doesn't mean the rest of us won't buy it.

    PS3/XBOX came out in 2005, or about 7 years now. i have no issues buying the latest game and still play.

    what phone or pad did you have 7 years ago? oh, you have nothing... heck, the phones/pads you bought 3 years ago probably wont' be able to run today's game.
    Reply
  • tipoo - Wednesday, March 28, 2012 - link

    Tegra Zone enhancements, the article mentions that. Reply
  • PeteH - Wednesday, March 28, 2012 - link

    What mechanism is being used to upscale legacy (1024x768) apps? Pixel doubling? Bi-cubic? Bi-linear? Something else? Reply
  • Guspaz - Wednesday, March 28, 2012 - link

    At the most basic level, pixel doubling. However, text that is rendered through iOS gets a free resolution boost so long as the app was compiled with the latest version of xcode. It's pretty common on the iPad 3 to see apps where the interface elements are low-res, but all the text is high-res. And in apps that are predominantly text (like an SSH client, for example), that's all that really matters. Who cares if the triangle picture on a button isn't high res?

    For stuff like games, that stuff is just pixel doubled.
    Reply
  • PeteH - Wednesday, March 28, 2012 - link

    I'm not saying you're wrong, but how do you know games (for example) utilize pixel doubling? Reply
  • Guspaz - Wednesday, March 28, 2012 - link

    I know because I can look at a game that doesn't support the new screen (such as Plants vs Zombies HD) on my iPad 3 and see that it's using pixel doubling? It does the same for iPhone apps when you use the 2x zoom option. One thing I have not tried is an old 320x480 iPhone app. I'm curious, since that would require 4x zoom.

    Newer games may choose to render at a lower resolution and then upscale using some sort of filter (perhaps even on the GPU), but at that point they are specifically targeting the new display. An older game that is completely oblivious to the newer display is scaled by the OS using pixel doubling without any interaction from the game.
    Reply
  • Steelbom - Thursday, March 29, 2012 - link

    Actually, when using iPhone apps, the iPad uses the 640x960 version rather than the 320x480 version, if available. Reply
  • mosu - Wednesday, March 28, 2012 - link

    A person in his 50's doesn't care about 300dpi res because he only sees 200dpi, so retina display is just for kids? I really don't get why Apple did not use a standard res panel like 1920x 1200 if they wanted a greater quality image.It means they're stuck with a single form factor? Reply
  • PeteH - Wednesday, March 28, 2012 - link

    It's much easier to stick with a single aspect ratio, especially for the developers. Your app looks the same on every device (albeit sharper on higher DPI displays), no need to tweak things for multiple aspect ratios. Reply
  • Sabresiberian - Thursday, March 29, 2012 - link

    Umm, where do you get this idea?

    Generalized statements about vision limitations in humans are usually taken out of context, at best.

    ;)
    Reply

Log in

Don't have an account? Sign up now