CDMA is spread spectrum technology, which means that it spreads the information contained in a particular signal of interest over a much greater bandwidth than the original signal. When implemented in 题目和参考答案——青夏教育精英家教网—

题目内容

CDMA is " spread spectrum (频谱) " technology, which means that it spreads the information contained in a particular signal of interest over a much greater bandwidth (带宽) than the original signal.
When implemented (实现) in a cellular telephone system, CDMA offers numerous benefits to the cellular operators and their subscribers (订户). Following is an overview of CDMA benefits:
1. Improved call quality, with better and more consistent sound.
2. Simplified system planning through the use of the same frequency in every sector of every cell.
3. Increased talk time for portables.
4. Bandwidth on demand.
Compared with GSM ( Global System for Mobile communication ), which was developed mainly in Europe, the CDMA system matured (成熟) later and has better efficiency, low radiation, high voice quality and ability to adopt third-generation communications technology.
China, Indonesia, Japan, South Korea and now India will make up the major market for CDMA technology in addition to the United States, the Republic of Korea, Japan and Australia to ensure that CDMA users can receive phone calls from overseas.
56. Which of the following statements is TRUE?
A. CDMA has a clearer and higher sound than GSM.
B. You will not hear a better and more consistent sound if you don't use CDMA.
C. CDMA has the ability to adopt third-generation communications technology.
D. The original signal cannot satisfy the demand for bandwidth.
57. Which of the following statements is NOT true?
A. CDMA has low radiation and high voice quality.
B. CDMA can help you to have a long-time talk.
C. China and some Asian countries will have a large market for CDMA technology in future.
D. It's much simpler to use CDMA than GSM.
58. What is the main idea of this passage?
A. Compared with GSM, CDMA has more benefits.
B. Some information on CDMA and its advantages.
C. CDMA will probably take the place of GSM some day.
D. CDMA is more effective and healthy.

56-58 CDB

解析

练习册系列答案

寒假作业与生活陕西人民教育出版社系列答案

寒假作业陕西旅游出版社系列答案

相关题目

阅读理解

　　CDMA is"spread spectrum(频谱)" technology, which means that it spreads the information contained in a particular signal of interest over a much greater bandwidth(宽带)than the original signal．

　　When implemented(实现)in a cellular(手机)telephone system, CDMA offers numerous benefits to the cellular operators and their subscribers．Following is an overview of CDMA benefits：

　　1．Improved call quality, with better and more consistent sound．

　　2．Simplified system planning through the use of the same frequency in every sector of every cell．

　　3．Increased talk time for portables．

　　4．Bandwidth on demand．

　　Compared with GSM(Global System for Mobile communication), which was developed mainly in Europe, the CDMA system matured(成熟)later and has better efficiency, low radiation, high voice quality and ability to adopt third-generation communications technology．

　　China, Indonesia, Japan, South Korea and now India will make up the major market for CDMA technology in addition to the United States, the Republic of Korea, Japan and Australia to ensure that CDMA users can receive phone calls from overseas．

(1)

Which of the following statements is TRUE?
[　　]
A．	CDMA has a clearer and higher sound than GSM．
B．	You will not hear a better and more consistent sound if you don't use CDMA．
C．	CDMA has the ability to adopt third-generation communications technology．
D．	The original signal cannot satisfy the demand for bandwidth．

(2)

Which of the following statements is NOT true?
[　　]
A．	CDMA has low radiation and high voice quality．
B．	CDMA can help you to have a long-time talk．
C．	China and some Asian countries will have a large market for CDMA technology in future．
D．	It's much simpler to use CDMA than GSM．

(3)

What is the main idea of this passage?
[　　]
A．	Compared with GSM, CDMA has more benefits．
B．	Some information on CDMA and its advantages．
C．	CDMA will probably take the place of GSM some day．
D．	CDMA is more effective and healthy．

“Any time! Any where! Decades ago there was no such thing” – “Communication”.

Then, September 7th 1987, the global system for mobile communication or GSM was born. And international agreements that laid out the standards, regulations and practices gave rise to a global mobile phone industry.

To be honest, the world’s first mobiles were not so attractive and the range of effectiveness wasn’t very good. But they became a must-have among those wealthy people who could afford that. However, by advantage of GSM which has many different elements to it, we can all enjoy the ability to go around the world in 217 countries, land in that country and know that a phone would work.

There are other cell phone systems using different technology in the world. The majority of the United States and parts of South America have been using something called CDMA which is very rare in Europe. In some Asian countries like China, GSM and CDMA both exist at the same time. But the GSM Association claims 85% of the global mobile phone market. They estimated there are now about 2.5 billion different users who make more than 7 trillion minutes of calls everyday, and that’s not all.

20 years later, the mobile phone is so much more than just a phone. You can use it to send text messages, take pictures, show video, even surf the internet.

“The phone itself is involved from just being a communication tool, to be a tool for round-the-clock connectivity, you can not live without it even in a minute.” Mobile consultant Nick Lane also points out with so many customized styles and features, your mobile phone will become a symbol of you.

Where will the global mobile phone industry be in another 20 years? Certainly, there will be more connections than better coverage. As for where else technology will take us, one can only imagine.

According the passage, we can know that GSM is ____________.

A. a global-used mobile phone B. a global mobile phone industry

C. a global mobile phone association D. a global mobile communication system

From this passage, we can infer that ____________.

A. as soon as the first mobiles appeared, they became popular and many people have one

B. with a GSM mobile phone, you can make a phone call in most parts of the USA

C. there are only two cell phone systems in the whole world: GSM and CDMA

D. most of the mobile phone users in the world now are using the GSM mobile phone

By pointing out “your mobile phone will become a symbol of you”, what does Nick Lane want to tell us about the mobile phone in the future?

A. You can have a mobile phone with the unique look and functions as you like.

B. Others can find us without any difficulties if we carry our mobile phone.

C. The mobile phone can be used as a permit when you enter some places.

D. The mobile phone we carry can show others how wealthy we are.

What does the writer feel about the GSM development in the following 20 years?

A. Satisfied. B. Worried. C.Confident D. Confused.

“Any time! Any where! Decades ago there was no such thing” – “Communication”.

20 years later, the mobile phone is so much more than just a phone. You can use it to send text messages, take pictures, show video, even surf the internet.

Where will the global mobile phone industry be in another 20 years? Certainly, there will be more connections than better coverage. As for where else technology will take us, one can only imagine.

1.According the passage, we can know that GSM is ____________.

A. a global-used mobile phone B. a global mobile phone industry

C. a global mobile phone association D. a global mobile communication system

2.It's most difficult to find a CDMA mobile phone in ____________.

A. the United States B. South America C. Europe D. China

3.From this passage, we can infer that ____________.

A. as soon as the first mobiles appeared, they became popular and many people have one

B. with a GSM mobile phone, you can make a phone call in most parts of the USA

C. there are only two cell phone systems in the whole world: GSM and CDMA

D. most of the mobile phone users in the world now are using the GSM mobile phone

4.By pointing out “your mobile phone will become a symbol of you”, what does Nick Lane want to tell us about the mobile phone in the future?

A. You can have a mobile phone with the unique look and functions as you like.

B. Others can find us without any difficulties if we carry our mobile phone.

C. The mobile phone can be used as a permit when you enter some places.

D. The mobile phone we carry can show others how wealthy we are.

5.What does the writer feel about the GSM development in the following 20 years?

A. Satisfied.　　 B. Worried.　　 C. Confident.　　 D. Confused.

When implemented (实现) in a cellular telephone system, CDMA offers numerous benefits to the cellular operators and their subscribers (订户). Following is an overview of CDMA benefits:

1. Improved call quality, with better and more consistent sound.

2. Simplified system planning through the use of the same frequency in every sector of every cell.

3. Increased talk time for portables.

4. Bandwidth on demand.

Compared with GSM ( Global System for Mobile communication ), which was developed mainly in Europe, the CDMA system matured (成熟) later and has better efficiency, low radiation, high voice quality and ability to adopt third-generation communications technology.

56. Which of the following statements is TRUE?

A. CDMA has a clearer and higher sound than GSM.

B. You will not hear a better and more consistent sound if you don't use CDMA.

C. CDMA has the ability to adopt third-generation communications technology.

D. The original signal cannot satisfy the demand for bandwidth.

57. Which of the following statements is NOT true?

A. CDMA has low radiation and high voice quality.

B. CDMA can help you to have a long-time talk.

C. China and some Asian countries will have a large market for CDMA technology in future.

D. It's much simpler to use CDMA than GSM.

58. What is the main idea of this passage?

A. Compared with GSM, CDMA has more benefits.

B. Some information on CDMA and its advantages.

C. CDMA will probably take the place of GSM some day.

D. CDMA is more effective and healthy.

试题分类