IEE802.14 is certainly pursuing advanced modulation for the upstream, since it is generally accepted that QPSK will not scale (although it is fine for early deployments). There are a half-dozen or so competing approaches (DMT, VCMT, DWMT, CDMA, OFDM, etc.), and originally the committee seemed receptive to a standard which would embrace several options, allowing the market to sort out the winners and losers. They have recently decided to adopt a single approach, however, which means there will be a huge fight among the backers of each of the approaches, with the result that nothing is likely to come out of the committee anytime soon, and by the time they decide, it will be largely irrelevant (market will have already spoken by then).
The more relevant group for the US is probably MCNS, which is the standard-setting body for the cable industry. |
