|reply to Matt3 |
said by Matt3:Per MHz, HSDPA is more efficient than EV-DO (even Rev.A). EDGE can do 2.3Mbps per MHz under ideal conditions on a single sector (with frequency reuse, more like 384Kbps per sector), but has terrible latency and a limit of about 300Kbps per device under ideal conditions. There are network limitations that reduce speed further, but a data only EDGE network could actually be quite fast.
I don't think that would occur. It's my understanding that CDMA and EVDO are inherently more efficient than GSM/HSDPA.
HSDPA as currently deployed by at&t does a maximum theoretical speed of 7.2Mbps per 5MHz or 1.44Mbps/MHz or 2.88Mbps/MHz if they deploy the HSDPA 14.4 upgrade.
EV-DO Rev.A has a maximum theoretical spectral efficiency in a data only of about 2.5Mbps/MHz, although that fails to take into account the significant penalty for having to have a separate 1.25MHz channel dedicated to voice and 1xRTT data.
So HSDPA and EV-DO are pretty close in theoretical spectral efficiency, with HSDPA enjoying the advantage on fully upgraded networks. (There are a few around the world, FWIW) Both are significantly better than EDGE when the reuse factor is taken into account.
It's wierdo, not weirdo. Yes, I know that's not the 'proper' spelling of the similar english language word.