Long before Sirius Backseat TV was even announced, many a satrad geek has questioned how much bandwidth would be required to deliver the mobile video entertainment.

Well, the math-geniuses over at Satellite Radio TechWorld have a pretty darn good theory. Based on Sirius' response to a complaint filed by the WCS Coalition about Sirius Backseat TV, we learn that the video programming will use less than 1/5 of its bandwidth.

Now for some number crunching:

"So, we can calculate that [Sirius Backseat TV] will consume 2.5 MHz of the 12.5 MHz band, or 0.625 to 0.833 MHz per channel. Since it is broadcast on 3 carriers (two satellites and one repeater), the numbers have to be divided by 3, meaning that each channel per carrier will consume 208 to 278 KHz. If we understand the technology correctly, that should translate into video streaming somewhere on the order of 625 to 833 kbps per channel."

That might be our nearest indicator as to the level of quality to expect for the service. The demo at CES looked pretty damn good, though that could have been, well, just a demo.

[Satellite Radio TechWorld] 

XM Satellite Radio has announced that it will enhance its popular XM WX Weather package (most people just call it XM Weather), adding more features at no additional charge.

"We're excited to announce the expansion of coverage to Canada and Puerto Rico," said XM spokesman Roderick MacKenzie at the Sun 'n Fun Fly-In in Lakeland, Fla.

XM WX Weather will include Canadian weather products such as Weather Warnings, Outlooks, METARs, SIGMETs, and winds aloft. And who doesn't need METARs, SIGMETs and winds aloft? I know I sure can't live without 'em.

XM also said it will offer subscribers an "End of Season" package that allows them to put their payments on hold during the off-season when they don't need the service. It's not being thrifty, it's called common sense.

The "End of Season" package will reportedly also be available for the "consumer" version of XM WX, called XM WX SkyWatch. With limited fishing and hunting seasons, this would definitely help sell the service for the outdoorsy type who wants to rock out to XMLM while on the duckboat.

[AV Web]