Last Active
  • USB4 Version 2.0 to offer up to 80 Gbps data transfer

    urahara said:
    Here is a sequence for you to come down a little: 802.11 -> 802.11b -> 802.11a -> 802.11g -> 802.11n -> 802.11ac -> 802.11ax -> 802.11be ;)

    WiFi's more of a tree with branches. Some standards are band dependent.

    2.4GHz = 802.11b -> 802.11g -> 802.11n
    5GHz =  802.11a -> 802.11n -> 802.11ac (WiFi 5) -> 802.11ac Wave 2 -> 802.11ax (WiFi 6) -> WiFi 6E -> 802.11be (WiFi 7)
    6GHz = 802.11ax (WiFi 6E) -> 802.11be (WiFi 7)
    60GHz = 802.11ad -> 802.11ay

  • Elon Musk and T-Mobile try beating Apple with satellite vaporware

    I'm guessing a lot of people didn't watch the event.

    This will use a thin slice of existing T-Mobile mid-band (PCS, 1900-2100MHz) spectrum, which they have licenses for across the entire US.  This isn't necessarily 5G, and they said "the phone you already have."  I'm guessing that they'll only need to implement the 4G/LTE spec (or a lite version of it), enough to support voice and simple data.

    According to Musk, the antennas to support this will be roughly 5-7 meters wide and tall, and there will be serious electronics involved to counteract doppler effect etc. Because cell phones transmit omnidirectionally, cell antennas on towers are already designed to be really big ears to pick up the weakest of signals.  Licensed spectrum is much quieter than Part 15 (unlicensed) bands where WiFi and baby monitors and IoT devices live.  So they wouldn't have put out the "vaporware" if they didn't believe there was technical capability. 

    There's also only so much bandwidth available (2-4Mbps) for the whole spot beam, so they're starting with the easy stuff. SMS uses the SS7 signaling network (which runs on most telco phone switches across two 56K channels). They've got oodles of bandwidth to support texting and messaging, and with store-and-forward capabilities onboard the bird, that part's pretty much figured out.

    Since T-Mobile already owns the spectrum, the biggest challenge could be regulatory issues.
    just cruisinmuthuk_vanalingamhtbduryeigoh
  • Apple's M1 Ultra combines two M1 Max into a powerhouse chip

    The keynote also mentioned "the last" M1 chip in the lineup was Ultra.

    My bet is Mac Pro gets M2 (Max/Ultra) with each chip having 2 interconnects instead of one and perhaps 128GB per package, supporting quad/hex/octo configs within insane core counts.
  • T-Mobile will shut down Sprint's 3G network in March

    davgreg said:
    The only area rough around the edges is the millimeter wave 5G which is still problematic. I was in Nashville near Vanderbilt Thursday and the millimeter wave was up and running but the network not well optimized - crazy fast signals outside and nothing inside a simple brick restaurant. It was like this in Memphis recently as the same tech was rolled out but was much improved within a month or so.
    Physics.  The lower the frequency, the greater the likelihood it will travel far and go through objects.  Converse is true: the higher the frequency, the shorter the distance traveled and the more likely items are to interfere with that frequency's propagation.

    Lower bands = lower bandwidth channels; higher frequency bands = huge bandwidth channels.  Wider channels travel shorter distances; narrower channels can go further, generally speaking.

    The addition of 700MHz for LTE and 600MHz for 5G to T-Mobile's portfolio mean they will benefit tremendously from the lower frequencies, but you won't get crazy fast on those bands at great distance (I would argue that anything over 100Mbps to a cell phone > 1 mile away is pretty cool).

    Millimeter wave bands such as 28-47GHz, their Part 15 counterparts, 24GHz and 60GHz, and the lightly-licensed 70/80GHz E-band are amazing. I have deployed point-to-point links on 24-, 60-, and 70/80GHz, and they range in capacity from 1Gbps to 10Gbps.

    But those frequencies don't propagate through most solids. The antennas have to have line of sight to each other. At anything over 18GHz, rain begins to cause problems. 
    At 58-65GHz, oxygen absorbs the signal. Human bodies certainly have a blocking effect, and building walls most certainly will too.

    The 5G spec has all kinds of redudnancy/resiliency/aggregation built in to allow the phone's radios to switch back and forth between bands, based on what's available.

  • This is why Apple TV 4K Siri Remote scrubbing doesn't work on Disney+, other apps

    Apple's player API is extremely limiting if you want to do custom overlays, play more than one program at a time (2-,3-,4-up), or preview information from other channels or programs, etc. You also have limits on knowing if the content meets the user's content restriction criteria because they don't make that available unless you use their player controller. There's more than one reason there are dozens of custom player API's.  Most of them are lousy.

    I wrote my own that supported swiping to scrub through the stream, among other things. I wouldn't be surprised if Apple announces those API's at WWDC next week and all this hoopla is over nothing, presuming the dev teams adopt the new gesture recognizers.

    rundhvidwilliamlondonMacProforgot usernamefastasleep