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  • DigitalFreak - Thursday, January 5, 2012 - link

    I don't even see a point to the BCM43526. It's USB 2.0, yet has a wireless transfer rate of up to 866Mbps? Even the 43516 is iffy.
  • quiksilvr - Thursday, January 5, 2012 - link

    It's 2 spatial streams so its usb 2.0 x 2.
  • jing0201 - Monday, February 6, 2012 - link

    Do you mean that will have 2 port of USB?
  • dagamer34 - Thursday, January 5, 2012 - link

    I'd expect then to make USB 3.0 versions soon. But heck, even 2.0 versions would be faster if you got 300Mbps in real world speed.
  • zorxd - Thursday, January 5, 2012 - link

    866 Mbps is the maximum theoretical speed. Expect the real world speed to be below 480 Mbps.
  • name99 - Thursday, January 5, 2012 - link

    There are a number of issues here.
    Most important is that 866 Mbps refers to the rate at which bits are encoded (under optimal conditions) in a single packet. But under normal conditions you don't get to send an uninterrupted stream of packets one after the other with no gaps --- you have to share the radio waves with everyone else who is also using the network, even if the only other user is the base station sending you ACK packets.

    So the point is 866 Mbps doesn't refer to the LONG-TERM data rate of connection, just to its instantaneous rate. What will happen in practice is that the data will come in as a steady stream through the USB interface and be buffered, to be shot out over the wireless occasionally at a faster rate.

    Yes, if everything were lined up perfectly, the maximum data rate you could probably get over the wireless connection is maybe around 450Mbps (I don't know enough about the changes in the spec regarding MAC and timings to know if you could do better than that, so let's use the rule of thumb that for existing WiFi sustained you get about half the nominal bit rate). Obviously in that case you're going to be throttled by the USB connect to about 300Mbps. BUT
    (a) that's still a lot better than you're getting now and
    (b) under normal conditions (you're far from the base station, you have a lot of interference, you're sharing with a few other users) the maximum sustained wireless speed you're going to see is less than 300Mbps so it's a moot point.

    The two streams of the 43526 is still going to give you better performance, and more consistent performance in the face of noise, than the single stream of the 43516.
  • iwodo - Thursday, January 5, 2012 - link

    Well as they have stated in the primer, you will properly never get that theoretical maximum speed even if you are standing right next to the receiver.

    Even with full signal you should , and may be increased efficiency you should expect the maximum real world speed to be 50 - 60% of Max theoretical, around 520Mbps, now add in interference and other crap. I bet 80% of the time you wont be saturating your USB Real World 256Mbps speed.

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