re: IS "SATELLITE RECEPTION" *really* the basis for Internet, TV, and "Global Communications"?

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Thank you for weighing in... Regarding the above referenced tech specs, can you kindly explain to the class to what extent "C-band and Ku-band frequency ranges" have been be utilized? Thanks.

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Sure. In the US, Latin America, and SE Asia, linear television signals have been traditionally distributed via C-Band; Europe and Middle East via Ku-Band. This is for BtoB transmission. Each head-end or aggregator would then downlink these signals, aggregate them and then retransmit via their platform (cable, BtoC satellite, etc.), to their customers.

The most efficient method of transmitting linear television channels is via satellite. When a television channel is uplinked to a satellite there is no incremental capacity cost for incremental users. Therefore, each broadcaster or aggregator has zero incremental capacity costs as they add subscribers which translates to higher incremental margins.

For the US market, C-band satellites for media transmission have typically been built with 24 transponders, each containing 36 MHz - that’s it.

For the longest time, each MHz on the satellite would transport roughly 1 Mbps. Each standard definition (SD) channel would occupy roughly 4 Mbps.

With the advent of High Definition (HD), better compression allowed each HD channel to require only 8 Mbps, and advanced modulation offered an enhancement in throughout to roughly 2:1 Mbps:MHz.

With the number of channels available (East and west coast feeds), including the large national broadcasters with local affiliates , coupled with the large number of sports broadcasts (ad hot satellite usage) transmission of syndicated shows, ads, etc., the US media market would typically occupy about 25-30 C-band and Ku-band satellites, with the Ku-band being primarily used for ad hoc sport and news transmission, syndicated programming, etc.

FYI - People actually so point their satellite dishes to satellites.

First, I appreciate your response AND detailed explanation.

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For the US market, C-band satellites for media transmission have typically been built with 24 transponders, each containing 36 MHz - that’s it...

...the US media market would typically occupy about 25-30 C-band and Ku-band satellites, with the Ku-band being primarily used for ad hoc sport and news transmission, syndicated programming, etc

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Is it your opinion that commercial "cable" providers like say Comcast would be able to maintain internet or TV service with the "Satellite" service of 36 MHz?

And to what extent of area coverage (i.e., Global / National / Regional / Town / Military Base)?

Are these considered "Emergency Contingency Use" should the Land-Based cables / comm go down?

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FYI - People actually so point their satellite dishes to satellites.

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Who or what is your definitive source for this? (Just one will do)

I don't doubt your technical/engineering knowledge. If you don't mind my asking -- is your knowledge in the Satellite-Tech-Comm field based in the Private or Public sector?

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First, I appreciate your response AND detailed explanation. quote: For the US market, C-band satellites for media transmission have typically been built with 24 transponders, each containing 36 MHz - that’s it... ...the US media market would typically occupy about 25-30 C-band and Ku-band satellites, with the Ku-band being primarily used for ad hoc sport and news transmission, syndicated programming, etc Is it your opinion that commercial "cable" providers like say Comcast would be able to maintain internet or TV service with the "Satellite" service of 36 MHz?

No. Just doing the math with the huge number of channels available, the require amount of Mbps is monstrous to offer the kind of bouquet that Comcast Xfinity offers. Additionally, think about all of the special event, PPV, VOD, DVR, etc., requirements that each consumer now demands. These traditional satellites have been used for 1-way linear television transmission; there has been no return communication via satellite with those services.


And to what extent of area coverage (i.e., Global / National / Regional / Town / Military Base)?

Based on the curvature of the Earth, it takes 3-4 geosynchronous satellites to cover the globe, excluding the polar regions. I’m making a generalization because the commercial satellite downlink footprints are designed to maximize beam strength in the populated areas. Here’s a link to one of the major global commercial communication satellite operators: LINK They recently acquired GoGo inflight WiFi operator since that service primarily operated in their fleet. The US television-transmission focused satellites cover the whole of the US, Caribbean, and parts of Mexico and Canada, based on each of their orbital slots ( some of the more easterly positioned satellite will yield poor reception in Alaska and Hawaii).



Are these considered "Emergency Contingency Use" should the Land-Based cables / comm go down?

I’m not sure, but I would say no, since there are so many land-based cables, terrestrial cable connectivity is extremely resilient. Plus, a single satellite wouldn’t make a dent in any real emergency.

quote: FYI - People actually so point their satellite dishes to satellites. Who or what is your definitive source for this? (Just one will do)

Just in the field with RF engineers locking receive dishes on numerous satellite that are positioned at certain azimuth and elevation based on each location accessed.

I don't doubt your technical/engineering knowledge. If you don't mind my asking -- is your knowledge in the Satellite-Tech-Comm field based in the Private or Public sector?

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Private sector, although I have decent knowledge of the public sector uses. I’ve also sat on the boards of international governing boards of some industry groups.

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quote: ... there is still a lot beamed down from Sats. That REAL number is actually ZIP. Believe what you need to believe.

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The communication satellites for television and internet distribution are just giant mirrors and amplifiers in the sky. They mitigate the issues related to land/sea and the curvature of the Earth. There’s no real intelligence on the satellites (for traditional commercial uses).

The GPS, weather, imaging and other governmental satellites DO have intelligence on them and are not simply reflectors in the sky.

Also, the large telecoms petitioned the FCC for part of the C-band spectrum traditionally used for television transmission to use it for 5G. After a few years of negotiation, the commercial satellite operators, major broadcasters, major telecoms and FCC agreed to a structured draw down of 100-300 MHz of C-Band capacity on the lower end of the C-Band frequency. The media and commercial satellite community received payment and have vacated the spectrum recently.

New C-Band satellites are now smaller since the number of transponders is lower. This transition has also accelerated advanced compression and modulation schemes as well as terrestrial IP-based transmission as an adjunct or replacement for traditional satellite distribution. Also, some broadcasters are now sending their signals to large Cloud computing providers and are requiring aggregators to “pick up” their channel(s) at various meet me points.

For those interested in the subject of satellites and their "orbiting" and purported use (commercial / military)...

Here is a very cool website that allows the user to hover in space or swoop down over all global positions and sectors of coverage; You can zoom IN and OUT from these "Satellites" or "starlinks".

'Constllation starlink'

Some of you probably know this, but NASA uses BALLOONS as stationary "outposts" -- in other words, as "Satellite" transponders. "Orbiting"? Well, they may drift above us or be guided remotely, but this situation is what it is.

Someone once told me, "Truth is like poetry".

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There’s no real intelligence on the satellites (for traditional commercial uses).

The GPS, weather, imaging and other governmental satellites DO have intelligence on them...

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I'd already assumed the above; General Mills and Costco do not need a "satellite". Govt OTOH = "The Weatherman", "G00gle Earth", Car Nav, Target Sat

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Here's the conundrum here; If positioning of Satellite dishes on houses is stationary, how is it possible to "LOCK IN" on one specific orbiting Satellite for consistent reception IF that Satellites is whizzing away at a different position thousands of miles an hour?

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quote: It takes 3-4 geosynchronous satellites to cover the globe, excluding the polar regions. So if I'm to understand the concept -- 3-4 satellites "orbit" AND cover the entire globe / realm per day?

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There are commercial satellites positioned at roughly every 2 degrees. Each satellite can cover (at maximum beam) between 1/4-1/3 of the globe based on their geosynchronous positions the sky. Based on their elevation at >20,000 miles high, the 1/4-1/3 planetary coverage is naturally limited by the curvature of the earth. For example, if you used a satellite at 90 deg W, you’d need another at 180 deg W, then 270 deg W (90 deg E), and then at 0 deg. If you used a satellite 10 degrees further west, then all others would need to be positioned 10 degrees further west.

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quote: The US television-transmission focused satellites cover the whole of the US, Caribbean, and parts of Mexico and Canada, based on each of their orbital slots ( some of the more easterly positioned satellite will yield poor reception in Alaska and Hawaii). I'm a bit confused here; To your knowledge, the "TV reception-transmission" signal from Satilittes that you refer to -- are NOT Comcast / Commercial capable; but instead *might* be useful in a singular events -- like a Closed Circuit event?

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They are commercial but they carry signals that would then be downlinked by aggregators such as Comcast, Dish, Cox, etc. Those providers then aggregate and retransmit with their proprietary bells /whistles. For Dish/DirecTV, they aggregate and retransmit on their satellites for B to C.

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quote: RF engineers locking receive dishes on numerous satellite that are positioned at certain azimuth and elevation based on each location accessed. Here's the conundrum here; If positioning of Satellite dishes on houses is stationary, how is it possible to "LOCK IN" on one specific orbiting Satellite for consistent reception IF that Satellites is whizzing away at a different position thousands of miles an hour?

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Good question. That’s the magic of the geosynchronous satellites. Once they’ve reached their orbital slot, let’s say 90 deg W (and all of the geosynchronous satellites are directly over the equator), it takes very little fuel on the satellite to provide station keeping to keep them in that exact spot in the sky. It’s amazing, but that specific height allows them to stay at 90 deg W with very little effort.

I appreciate the exchange of thoughts and info.