China's defunct Tiangong-1 space lab is expected to make a fiery re-entry into the earth's atmosphere in the coming days and disintegrate in what Chinese authorities promise will be a "splendid" show.
Space Exploration
Mar 30, 2018
0
17
(AP) -- The rapid growth of smart phones and electronic tablets is making the Internet the destination of choice for consumers looking for news, a report released Monday said.
Internet
Mar 14, 2011
1
0
An Amazon device powered by the Alexa voice software recorded a couple's private conversation in their home and sent it to someone in their contact list without their knowledge, KIRO television reported.
Consumer & Gadgets
May 28, 2018
0
17
A baffling solar storm pulled colorful northern lights unusually far south, surprising space weather experts.
Space Exploration
Oct 25, 2011
5
2
Europe's satellite launch industry needs to be overhauled to keep up with tough challenges from US rival SpaceX and other emerging competitors, the head of European satellite giant Arianespace has said.
Space Exploration
Jun 18, 2014
0
0
Television and radio broadcasts used to be free. Stick an antenna in the air and that's still true even though much of it has now gone digital. As technology advanced, we got better delivery methods of those free signals ...
Telecom
Aug 13, 2009
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0
North Korea recently launched a cyber attack on South Korean TV stations and banks. Iran carried out a cyber campaign against U.S. banking sites. The U.S. and Israel released malware that disabled Iranian nuclear centrifuges. ...
Internet
Apr 12, 2013
1
0
A new law could result in fewer TV stations on the air, in exchange for faster wireless data services for smartphones and tablet computers.
Telecom
Feb 28, 2012
5
0
Verizon Wireless on Wednesday said it will auction a parcel of radio frequencies, which could be worth billions of dollars in an industry scrambling to offer consumers more cellular broadband.
Telecom
Apr 18, 2012
2
0
The National Football League has struck a deal with Google Fiber for carriage of its two cable channels on the search engine's new broadband distribution service it is offering in Kansas City, Mo., and Kansas City, Kan.
Telecom
Sep 7, 2012
0
0
A television channel is a physical or virtual channel over which a television station or television network is distributed. For example, in North America, "channel 2" refers to the broadcast or cable band of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video (VSB) and 59.75 MHz for analog audio (FM), or 55.31 MHz for digital ATSC (8VSB). Channels may be shared by many different television stations or cable-distributed channels depending on the location and service provider.
Depending on the multinational bandplan for a given region, analog television channels are typically 6, 7, or 8 MHz in bandwidth, and therefore television channel frequencies vary as well. Channel numbering is also different. Digital television channels are the same for legacy reasons, however through multiplexing, each physical radio frequency (RF) channel can carry several digital subchannels. On satellites, each transponder normally carries one channel, however small, independent channels can be used on each transponder, with some loss of bandwidth due to the need for guard bands between unrelated transmissions. ISDB, used in Japan and Brazil, has a similar segmented mode.
Channel separation on over-the-air channels is accomplished by skipping at least one channel between two analog stations' frequency allocations. (It should be noted that there are gaps between certain channels, where numbers are sequential, but frequencies are not contiguous, such as the skip from VHF low to high, and the jump to UHF.) On cable TV, it is possible to use adjacent channels only because they are all at the same power, something which could only be done over the air if the two stations were transmitted at the same power and height from the same location. For digital TV, selectivity is inherently better, therefore channels adjacent (either to analog or digital stations) can be used even in the same area.
This text uses material from Wikipedia, licensed under CC BY-SA
