来源 ：人民网财经 2019-11-15 07:56:59|盲人四柱预测详解
Get ready for some changes to good old broadcast TV.
After years of planning and study, ATSC 3.0, also known as Next Gen TV, is nearly here. Several US stations have already started broadcasting. But that doesn't mean you need to rush out and buy a new ATSC 3.0-ready TV -- in fact, right now you can't.
Next Gen TV has the capability to broadcast high-quality Ultra HD 4K video, HDR and wide color gamut, high frame rates up to 120Hz, and more. Like current over-the-air TV broadcasts -- and unlike cable, satellite or live TV streaming -- it will be free. You'll just need an antenna and a TV or separate tuner that can decode it. ATSC 3.0 proponents also claim better reception indoors and on the go, perhaps on your phone or even to your car.
Read more: Best TV antennas for cord-cutters, starting at just
One potential downside for consumers? ATSC 3.0 will also let broadcasters track your viewing habits, information that can be used for targeted advertising, just like websites and companies like Facebook and Google use today.
Here's the top-line info:
For a deeper dive into the features of ATSC 3.0, check out our original article. Though many of the features are listed as possibilities, most are being implemented according to the latest specification.
The short version? Higher quality 4K video, for free, over the air.
Ultra HD resolutions, high dynamic range (HDR), wide color gamut and frame rates up to 120 frames per second are all in the mix. ATSC 3.0 will also support current HD and older, lower resolutions, so there's no need to convert them at the station (your TV will do it, and it typically does a good job). The use of OFDM broadcast technology instead of 8VSB used in the current system means that potentially there will be better reception indoors and near tall buildings. The HEVC "H.265" codec means higher quality and higher resolution signals can be broadcast without a massive increase in bandwidth. This is good, because there's no increase in bandwidth. Each TV station keeps its current 6MHz band.
Keeping an eye down the road, there's the possibility to add 8K resolutions in the future.
Beyond the image quality aspect, there are also other interesting features, like the ability to turn on your TV remotely to broadcast emergency signals (so that's sure to wake you up), have web-enabled interactive features and a way to include targeted ads. We'll get to that last one in a minute.
A demonstration of a Next Gen TV Olympic broadcast, co-hosted by WRAL-TV, NBC Universal and NAB in February 2018.
In November of 2017, the FCC approved ATSC 3.0 as the next generation of broadcast standard, on a "voluntary, market-driven basis" (PDF). It also required stations to continue broadcasting ATSC 1.0 (i.e. "HD"). This is actually part of the issue as to why it's voluntary.
During the mandatory DTV transition in the early 2000s, stations in a city were given a new frequency (channel, in other words), to broadcast digital TV, while they still broadcast analog on their old channel. These older channels were eventually reclaimed by the FCC for other uses when the proverbial switch was flipped to turn off analog broadcasts. Since that's not happening this time, stations and markets are left to themselves how best to share or use the over-the-air spectrum in their areas.
Because there's no new bandwidth, broadcasters will temporarily share transmitters. Two or more stations will use one tower for ATSC 1.0 (HD) broadcasts and those stations will use another tower for ATSC 3.0 (UHD) broadcasts. This will mean a temporary reduction in bandwidth for each channel, but potentially a limited impact on picture quality due to the better modern HD encoders. More info here.
Without a mandate, stations might not bother spending the money upgrading to 3.0. It's easy to see the end result of this being no stations, or not enough stations, agree to the costly upgrades in equipment that ATSC 3.0 entails. If that happens, ATSC 3.0 is dead before it starts, or at best, languishes for years until a less regulation-averse FCC makes the transition mandatory.
People involved with the transition now, however, are optimistic. Dennis Wharton, executive vice president of communications at the National Association of Broadcasters, pointed out to CNET that the improvement in quality, overall coverage and the built-in safety features mean that most stations would be enthusiastic to offer ATSC 3.0.
John Hane, president of the Spectrum Consortium (an industry group with broadcasters Sinclair, Nexstar and Univision as members), was equally confident: "The FCC had to make it voluntary because the FCC couldn't provide transition channels. [The industry] asked the FCC to make it voluntary. We want the market to manage it. We knew the market would demand it, and broadcasters and hardware makers in fact are embracing it."
So far, this seems to be the case. Stations in 40 markets across the country have promised to start broadcasting 3.0 before the end of 2020. Some early stations have already gone live, though even if you live in their areas you won't be able to see anything without hardware that, as yet, isn't available.
Given the competition broadcasters have with cable, streaming and so on, 3.0 could be a way to stabilize or even increase their income by offering better picture quality, better coverage and, most importantly, targeted ads.
Ah yes, targeted ads…
One of 3.0's more controversial features is a "return data path," which is a way for the station you're watching to know you're watching. Not only does this allow a more accurate count of who's watching what shows, but it creates the opportunity for every marketer's dream: targeted advertising.
Ads specific to your viewing habits, income level and even ethnicity (presumed by your neighborhood, for example) could get slotted in by your local station. This is something brand-new for broadcast TV. Today, over-the-air broadcasts are pretty much the only way to watch television that doesn't track your viewing habits. Sure, the return data path could also allow "alternative audio tracks and interactive elements," but it's the targeted ads and tracking many observers are worried about.
The finer details are all still being worked out, but here's the thing: If your TV is connected to the internet, it's already tracking you. Pretty much every app, streaming service, smart TV and cable or satellite box all track your usage to a greater or lesser extent.
Return data path is still in the planning stages, even as the other aspects of 3.0 are already going live. If we take a step back and look at how the physics of how it could work, there's a silver lining: it almost certainly would still require internet access. Most likely there will be an opt-out or opt-in option, but if this type of thing bothers you, just don't connect your TV to the internet. There's no way any TV could broadcast a signal with enough power for your local TV station to receive it. I mean, I suppose there's a darker timeline where the TVs have a 4G or 5G transmitter built in and talk to the network without any other connection from you -- but that seems pretty far-fetched. That would be costly to build and costly to run.
It's likely if the hoped-for mobile adoption of ATSC 3.0 happens, this return path would be far easier. However, that part of 3.0 is also further in the distance than the rest.
That said, we'll keep an eye on this for any further developments.
Another point of potential contention is getting ATSC 3.0 tuners into phones. At a most basic level, carriers like AT&T, Verizon and T-Mobile are in the business of selling you data. If suddenly you can get lots of high-quality content for free on your phone, they potentially lose money. Ever wonder why your phone doesn't have an FM radio tuner? Same reason.
T-Mobile made a preemptive strike along those lines in September 2017, writing a white paper (PDF) that, among other things, claims, "In light of the detrimental effects that inclusion of ATSC 3.0 can have on the cost and size of a device, the technology trade-offs required to accommodate competing technologies, and the reduced performance and spectral efficiency that it will have for other mobile bands and services, the decision as to whether to include ATSC 3.0 in a device must be left to the market to decide."
"The market" determined you didn't need an FM tuner in your phone, and in the few phones that had an FM tuner, if you bought it through an American provider, it was almost always disabled.
TV broadcasters, on the other hand, are huge fans of ATSC 3.0 on mobile phones. It means more potential eyeballs and, incidentally, a guarantee of active internet access for that return data path. Hane feels that tuners in phones is "inevitable," and feels that international adoption of ATSC 3.0 will help push it forward. Wharton says that the focus now is getting TVs to work, but mobile is in the plan.
It's highly unlikely the FCC, current or future, would make any sort of tuner mandate for mobile phones. There is talk of "gateways" that would receive the ATSC signals, and then send them over your home network via Wi-Fi for you to watch on any smartphone or tablet. A sort of Wi-Fi-enabled external tuner. In all likelihood these same "gateways" would also let your current TV see ATSC 3.0 signals.
It's also possible we'll see tablets, perhaps inexpensive off-brand Android tablets, with built-in tuners. But there's almost no chance of an ATSC tuner showing up in an iPhone.
Then there's portable TVs, of which there are HD versions on the market, and have been for years. The next-generation ATSC 3.0 versions of these will likely get better reception in addition to the higher resolution offered by the new standard.
ATSC 3.0 is not compatible with any tuner on the market now, nor is it in any way backward compatible. To get it, you'll eventually need either a new TV or an external tuner, neither of which are currently available. We should start seeing tuners, and perhaps TVs, in 2020. Most likely these early models will be expensive, but that isn't an issue, since:
For those that do get TV over the air, point 2 is key. Broadcasters have to broadcast regular old HD for five years after the launch of 3.0. In those five years you'll probably get a new TV, or worst case, have to eventually buy an external tuner. Here's the actual language:
"The programming aired on the ATSC 1.0 simulcast channel must be 'substantially similar' to the programming aired on the 3.0 channel. This means that the programming must be the same, except for programming features that are based on the enhanced capabilities of ATSC 3.0, advertisements and promotions for upcoming programs. The substantially similar requirement will sunset in five years from its effective date absent further action by the Commission to extend it."
In other words, the HD broadcast has to be essentially the same as the new 3.0 broadcast for five years, perhaps longer depending on future FCC actions.
Which brings us to point 3. HD tuners were inexpensive when they first came out, and are even more so now. The HD tuner I use is currently on Amazon. Even if ATSC 3.0 tuners are more expensive when they first come out, by the time anyone actually requires one, they'll almost certainly be affordable.
Which is good, because there aren't any planned subsidies this time around for people to get a tuner for cheap. I'm sure this is at least partly due to how few people actually still use OTA as their sole form of TV reception. Maybe this will change as more stations convert, but we're a ways away from that.
As you can see, there are lots of parts that need to get upgraded all along the chain before you can get 3.0 in your home.
Here's another way to think about it: The first HD broadcasts began in the mid-90s, but when did you buy your first HDTV? As far as the 3.0 transition is concerned, we're in the mid-90s now. Things seem like they're moving at a much more rapid pace than the transition from analog to DTV/HDTV, but even so, it will be a long time before ATSC 3.0 completely replaces the current standard.
The transition from analog broadcasting to HD, if you count from the formation of the Grand Alliance to the final analog broadcast, took 16 years.
Though many aspects of technology move rapidly, getting dozens of companies, plus the governments of the US and many other countries, all to agree to specific standards, takes time. So does the testing of the new tech. There are a lot of cogs and sprockets that have to align for this to work, and it would be a lot harder to fix once it's all live.
But technology moves faster and faster. It's highly doubtful it will take 16 years to implement 3.0. As we mentioned at the top, multiple stations are already broadcasting, with many more scheduled to do so throughout 2019 and 2020. It seems that NAB's Wharton is going to be on the money with his prediction last year:
"The progress made on Next Gen TV has been remarkable. Lots of work remains, but we're cautiously optimistic that consumers will see Next Gen sets in stores by Christmas 2020."
Will every station in your city switch to 3.0? Probably not, but the bigger ones likely will. This is especially true if there are other 3.0 stations in your area. There's a potential here for stations to make additional money in the long run with 3.0, and that's obviously a big motivator.
There's also the question of how much content there will be. If it follows the HDTV transition model, big sporting events in 4K HDR will come first, followed by lots and lots of shows featuring nature scenes and closeups of bugs. Seriously -- this was totally a thing. Then we'll see a handful of scripted prime-time shows. My guess would be the popular, solidly profitable ones that are produced (not just aired) by networks. Series like Law & Order: SVU or Grey's Anatomy, and probably the late-night talk shows, are likely candidates, but that's speculation at this point.
So should you hold off buying a new TV? Nope, not unless you only get your shows over the air. And even if you do, by the time there's enough content to be interesting, there will be cheap tuner boxes you can connect to whatever TV you have.
For now, ATSC 3.0, aka Next Gen TV, seems to be right around the corner. I think it's safe to say we'll have even more to talk about at CES 2020.
Got a question for Geoff? First, check out all the other articles he's written on topics like why you shouldn't buy expensive HDMI cables, TV resolutions explained, how HDR works and more.
Still have a question? Tweet at him @TechWriterGeoff, then check out his travel photography on Instagram. He also thinks you should check out his best-selling sci-fi novel and its sequel.B:
盲人四柱预测详解【那】【一】【位】【中】【年】【男】【子】【在】【把】【马】【车】【给】【套】【好】【了】【以】【后】，【又】【重】【新】【的】【回】【过】【头】【来】，【对】【着】【陆】【大】【有】【和】【顾】【小】【宝】【小】【心】【的】【介】【绍】【说】【道】。 “【两】【位】【少】【侠】？【马】【车】【已】【经】【套】【好】【了】！” ”【这】【一】【匹】【马】【可】【是】【很】【温】【顺】【的】，【想】【要】【让】【他】【动】【起】【来】【也】【是】【很】【容】【易】【的】，【如】【果】【想】【要】【让】【他】【往】【左】【边】【走】，【那】【就】【抖】【一】【下】【他】【左】【边】【的】【缰】【绳】，【如】【果】【想】【要】【让】【他】【往】【右】【边】【走】，【那】【就】【抖】【一】【下】【他】【右】【边】【的】【缰】【绳】，【如】【果】
【好】【人】【国】【大】【乱】！ 【好】【人】【国】【的】【局】【势】【在】【渐】【渐】【失】【控】！ 【不】【仅】【好】【人】【国】【朝】【廷】【那】【边】【失】【去】【了】【对】【局】【势】【的】【掌】【控】【力】，【薛】【薇】【儿】【这】【边】【应】【付】【数】【以】【百】【万】【计】【的】【追】【随】【者】，【也】【是】【力】【不】【从】【心】【的】！ 【战】【乱】【和】【治】【理】，【完】【完】【全】【全】【就】【是】【两】【个】【对】【立】【的】【方】【面】，【薛】【薇】【儿】【本】【来】【以】【为】，【她】【掀】【起】【好】【人】【国】【的】【战】【乱】【的】【时】【候】，【迎】【来】【的】【是】【战】【争】，【却】【没】【想】【到】，【好】【人】【国】【朝】【廷】【那】【边】【竟】【然】【还】【是】【按】【兵】【不】【动】
【突】【如】【其】【来】【的】【变】【故】【惊】【到】【了】【南】【江】【河】【畔】【驻】【足】【的】【人】。 【朱】【雀】【雕】【像】【表】【面】【散】【发】【出】【金】【红】【色】【光】【芒】，【好】【似】【燃】【烧】【的】【火】【焰】【一】【般】。 “【朱】【雀】【显】【灵】【了】。” 【众】【人】【惊】【呼】。 【侃】【侃】【而】【谈】【的】【青】【年】【睁】【大】【眼】【睛】【盯】【着】【朱】【雀】【雕】【像】，【再】【三】【揉】【了】【揉】【眼】【睛】【确】【认】【自】【己】【有】【没】【有】【看】【错】。 【他】【之】【前】【说】【的】【那】【些】【话】【一】【部】【分】【是】【真】【的】，【一】【部】【分】【是】【他】【胡】【编】【乱】【造】【的】。 【他】【呆】【若】【木】【鸡】，【喃】
【大】【梁】【城】【中】。 “【大】【王】，【敝】【国】【本】【不】【欲】【再】【起】【战】【端】，【但】【是】【寡】【君】【深】【恨】【甘】【茂】【背】【信】【弃】【义】，【听】【闻】【甘】【茂】【离】【开】【秦】【国】【后】【被】【大】【王】【收】【留】，【所】【以】【这】【才】【派】【遣】【三】【十】【万】【大】【军】【前】【来】【缉】【拿】【甘】【茂】。 【是】【以】，【臣】【希】【望】【大】【王】【不】【要】【让】【敝】【国】【为】【难】，【交】【出】【甘】【茂】，【则】【敝】【国】【立】【即】【撤】【军】，【绝】【不】【迟】【疑】。” 【魏】【王】【遫】【听】【着】【楚】【使】【的】【要】【求】，【心】【中】【冷】【笑】【不】【止】。 【什】【么】【叫】【不】【欲】【再】【起】【战】【端】，【之】盲人四柱预测详解【三】【日】【后】，【起】【义】【军】【中】【已】【安】【排】【好】【军】【力】，【只】【等】【入】【夜】【后】，【趁】【着】【夜】【色】【悄】【悄】【埋】【伏】，【便】【可】【布】【下】【天】【罗】【地】【网】。 【斥】【候】【军】【不】【断】【进】【进】【出】【出】，【汇】【报】【最】【新】【军】【情】。 【霍】【清】【然】【心】【中】【终】【是】【有】【些】【放】【不】【下】，【自】【己】【出】【了】【营】【地】【策】【马】【巡】【视】。 【营】【地】【外】【到】【处】【都】【是】【人】【迹】【罕】【至】【的】【荒】【山】【野】【岭】，【没】【有】【人】【能】【料】【到】【这】【里】【有】【一】【天】【会】【成】【为】【两】【军】【交】【战】【之】【处】，【无】【数】【年】【轻】【的】【将】【士】【流】【尽】【鲜】【血】，【埋】
【铺】【天】【盖】【地】【的】【导】【弹】【降】【临】【到】【交】【战】【的】【中】【心】【地】【带】。 【光】、【热】、【冲】【击】【波】，【把】【大】【半】【个】【宜】【州】【市】【全】【部】【淹】【没】，【远】【处】【观】【察】【战】【场】【的】【士】【兵】，【除】【了】【火】【光】【什】【么】【也】【看】【不】【到】。 【第】【一】【波】【上】【百】【枚】【导】【弹】【发】【射】【之】【后】，【在】【不】【到】【五】【分】【钟】【的】【时】【间】，【又】【接】【连】【有】【两】【波】【导】【弹】【发】【射】。 【离】【宜】【州】【市】【三】【十】【公】【里】【外】【的】【人】，【都】【能】【感】【觉】【到】【明】【显】【的】【大】【地】【震】【动】，【就】【像】【是】【宜】【州】【在】【发】【生】【十】【级】【地】【震】【一】
【东】【广】【电】【视】【台】【在】【三】【月】【中】【旬】【播】【出】【了】【一】【起】【车】【祸】【的】【新】【闻】，【新】【闻】【里】【因】【为】【雨】【天】【加】【大】【风】【的】【缘】【故】，【一】【辆】【集】【装】【箱】【车】【的】【集】【装】【箱】【不】【知】【什】【么】【缘】【故】【就】【从】【集】【装】【箱】【车】【上】【掉】【下】【来】【了】，【很】【不】【幸】【地】【平】【砸】【在】【一】【辆】【正】【在】【超】【车】【轿】【车】【的】【车】【顶】。 【轿】【车】【的】【四】【个】【轱】【辘】【都】【砸】【塌】【了】，【但】【是】【轿】【车】【却】【没】【怎】【么】【滴】，【驾】【驶】【室】【虽】【然】【有】【轻】【微】【塌】【陷】【但】【还】【是】【板】【板】【整】【整】【地】【坐】【在】【马】【路】【上】。 【因】【为】【四】【个】【轱】