A
All networks like 3G and 4G will be things of the past, because 5G will be reachable in the near future. So, what’s so special about a 5G future? First of all, its download speed can be as fast as 20GB/s, which is 100 to 200 times that of 4G. But what’s more impressive is 5G’s low delay rate. Now, 4G takes an average of 200 milliseconds(毫秒) to send and receive information. But 5G will get it down to 1 millisecond.
5G is a great breakthrough. It’s going to change the way equipment connects to the Internet, and more importantly, to each other. And self-driving cars may be one of the biggest breakthroughs to come out of 5G. Human reaction time is 200 milliseconds, yet we still have accidents every day. The self-driving car under a 5G network could react and communicate its reaction to hundreds of cars around it, all within 1 millisecond. It’ll play a great role in preventing car accidents and ending traffic jams completely.
5G can benefit us in many other ways. Operations could be performed by robots controlled by experts from the other side of the world. Therefore, more lives will be saved in time. Factories can be staffed by robots that can communicate their tasks to each other, and they can do more work efficiently over a 5G network. Imagine a group of drones(无人机) flying over a field of crops, using sensors(传感器) on the ground to sort, pick, feed, and water plants all on their own. Then farmers won’t have to work so hard anymore.
However, 5G is not perfect. One major disadvantage has to do with why it’s so fast. 5G uses the millimeter waves, while 4G uses the 15 to 40 centimeter-long waves. And shorter waves go fast but not very far. On 4G networks, the signal can go 10 kilometers. But the 5G signal can go at most 300 meters, and it can’t even go through walls or rain. So, what does that mean? Having such a short signal distance means we need to build a lot of transmitters(信号发射塔) in the future.
1. How does the author show us 5G’s advantages in Paragraph 1?
A. By giving examples of the uses of 5G.
B. By making comparisons between 4G and 5G.
C. By explaining the scientific principles of 5G.
D. By analyzing 5G’s development from 4G.
2. According to the author, the self-driving cars will ________.
A. cause more car accidents
B. slow down 5G’s development
C. run without being connected to the Internet
D. have a much faster reaction speed than humans
3. What does the underlined part “be staffed by robots” in Paragraph 3 mean?
A. Be built by robots.
B. Have robots as workers.
C. Offer employees home robots.
D. Produce more medical robots.
4. What does the last paragraph mainly talk about?
A. The main weakness of 5G networks.
B. How to make 4G networks more perfect.
C. The types of long waves and short waves.
D. How to improve the signal of mobile phones.
