一起聽英語(yǔ) 91 衛(wèi)星導(dǎo)航系統(tǒng)
Alice: Hello, I'm Alice.
Stephen: And I'm Stephen.
Alice: And this is 6 Minute English! This week we’re talking about sat navs.
Stephen: Sat navs – that’s short for satellite navigation systems.
Alice: They’re the gadgets people put in their cars to help give them directions.
Engineers have been asking if we’re becoming too reliant on them. Before we
find out more, here’s a question for you, Stephen:
Stephen: Ok – I’m ready and waiting.
Alice: When we talk about ‘satellite navigation’ in English, there is an abbreviation
we use called GPS. Do you know what it stands for? I’ll give you some choices.
Is it:
a) greater place signal
b) global positioning signal, or
c) global positioning system
Stephen: I’m pretty sure I know the answer – but I won’t spoil it for everyone else. I’ll
tell you at the end of the programme.
6 Minute English © bbclearningenglish.com 2011
Page 2 of 6
Alice: That’s fine. Sat navs using GPS have become very popular in recent years. But
they can sometimes get people into trouble. The BBC News website has lots of
examples about people driving into rivers or getting stuck on roads which are
too narrow. This woman is talking about the lorries which keep getting stuck
under a 15th century stone archway in her town because they’re following
directions on their sat navs.
Insert 1: Woman
The amount of lorries that we see nearly every day - they get to that point and there’s no
signs anywhere. At the bottom of the road, it doesn’t say: “Don’t go down there - there’s
a bridge.” And they get to this point here and every one of them have to reverse - and
there’s cars everywhere. It’s just absolute mayhem.
Alice: Oh dear – she says it’s mayhem. Lorries either get stuck under the bridge or
they cause lots of problems trying to turn around - or to go backwards, to
reverse - on a very narrow road. She says it’s absolute mayhem.
Stephen: Mayhem – chaos.
Alice: In another incident, a car got stuck on the edge of a steep hill when its sat nav
directed it down a path which wasn’t suitable for vehicles any more. Antony
Chmarny, who works for a satellite navigation manufacturer, says the gadgets
should only be used as an aid to driving:
Insert 2:
Sat nav voice: Turn around when possible – then turn right.
Antony Chmarny: If it doesn’t look suitable, don’t drive down it, don’t drive down a
one-way street the wrong way if a sat nav tells you to do that.
6 Minute English © bbclearningenglish.com 2011
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Alice: I think he means, use your common sense – don’t drive down a one-way street
the wrong way even if a sat nav tells you to do it!
Stephen: I like the sat navs which you can programme with different voices – so you can
have your favourite singer or actor with you in the car as your navigator!
Alice: What a good idea! Let’s hear now from an engineer who is worried that we’re
becoming too reliant on sat nav and GPS technology. Professor Martyn
Thomas from the Royal Academy of Engineering says the weak radio signal it
uses can easily be messed up.
Stephen: Messed up – that’s interfered with, or destroyed.
Insert 3:
Professor Martyn Thomas: You can get interference – either deliberate or accidental
interference, because it is a very weak radio signal.
BBC interviewer Justin Webb: Yes, it’s quite easy, isn’t it, to mess it up?
Professor Martyn Thomas: Oh, extremely, yes. The radio signal is about the strength…
in light terms, it’s like looking at a 100 watt bulb from 12,000 miles away.
Justin Webb: So someone who really wanted to put out a large area – satellite
navigation systems, could do so?
Professor Martyn Thomas: Yes, you could. It would essentially have to be
jammed line-of-sight, so you’d have to do it from high ground.
Alice: Researchers were able to interfere with GPS signals on a ship using a
transmitter on high ground.
Stephen: A transmitter produces radio signals or interference - signals which, if strong
enough, can block other signals.
6 Minute English © bbclearningenglish.com 2011
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Alice: Professor Martyn Thomas said all kinds of things went wrong with the onboard
equipment on the ship.
Stephen: Without saying anything was wrong – incorrect – the ship reported that it was
travelling ten miles inland and moving faster than the speed of sound:
Insert 4: Professor Martyn Thomas
All kinds of things went wrong. The onboard equipment, that was reporting where they
were, at one point said that they were ten miles inland and moving faster than the speed
of sound. But more alarmingly, quite often the onboard systems, without saying
anything was wrong, was reporting their position as being just subtly wrong. And of
course, the onboard systems would broadcast that position and information to other
ships.
Alice: Professor Martyn Thomas from the Royal Academy of Engineering who thinks
we should be careful about becoming too reliant on GPS and sat navs, because
they can be interfered with. Apparently some people buy blocking gadgets to
put on their sat navs in company cars, so their employers won’t know where
they’ve been! Well, before we go, Stephen, can you tell us about the
abbreviation ‘GPS’?
Stephen: So, does it stand for global positioning system?
Alice: Yes, well done. So, before we go - a chance to hear some of the words and
phrases we’ve heard in the programme today: would you mind, Stephen?
Stephen: Sure.
satellite navigation systems
gadgets
6 Minute English © bbclearningenglish.com 2011
Page 5 of 6
abbreviation
mayhem
to reverse
aid
common sense
navigator
messed up
interfere with
Alice: Thanks, Stephen.
Stephen: You’re welcome.
Alice: Well, that’s all we have time for today. We’ll have more 6 Minute English next
time.
Both: Bye!
