First the news: Motorola announced the launch of a new universal edge QAM today, the APEX1000. In brief, edge quadrature amplitude modulators (QAMs) are used to translate signals from IP into radio frequency (RF). (Leslie Ellis explains it by saying this modulation turns spectrum into bandwidth.) Operators are finding they need more QAM channels of late because of growing demand for switched digital video (SDV), on-demand video, broadcast TV and DOCSIS data services. The issue of QAMs has been covered a bit recently because there is a cost associated with deploying more QAM channels even though at the same time they help operators save money and bandwidth by enabling SDV. (I’m hoping to have a deeper cost/benefit analysis some time soon.)
Confused? Don’t worry. The important thing to understand today is that a universal edge QAM makes it possible to use QAM channels for whatever services operators need most. In a single APEX1000 there are 48 QAM channels available, all of which can be used for SDV, VOD, broadcast TV or data service delivery.
Meanwhile, the APEX news is interesting in conjunction with an article Jonathan Tombes has out today. Tombes’ write-up in Cable 360 questions whether the pendulum has started to swing away from switched digital video, one of the big drivers for more QAM channels. I’d say the answer is no, but of course that comes across a little biased given Motorola’s interest in selling both QAMs and SDV technology.
So consider this: everyone has focused on SDV as a direct bandwidth-saving tool, but it has the potential to do much more. If operators can selectively switch on a particular channel, they can also selectively deliver different content formats depending on the technical set-up of a given subscriber. Bottom line: SDV provides an awful lot of flexibility, and plenty of benefit to justify spending a bit more on QAMs – especially when those QAMs can be swapped over for different uses as needed.
There are some very complex equations here, but what they mean is that operators can create the systems that work best for them. All it takes is a little math.