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Chinese standard has been subjected to several comparison tests with the interna
Author:   Source:dtvnel   Time:2011-03-15 13:46:00  Number: big middle small
From 2007 to 2009, Cuba, Venezuela, Peru, and Ecuador respectively carried out the comparison test of Chinese DTMB standard system with four similar digital standard systems of the United States, Japan,Europe, and Brazil. Chinese DTMB standard has made remarkable achievements and is ranked first in the technology evaluation, which had gotten attracted the attention of the leaders of CPC Central Committee and the State Council.


From December 18 to 26, 2007, a test team led by Beijing Haier,a member unit of Zhongguancun digital TV Industry Alliance (hereinafter referred to as the Industry Alliance),and participated by the units such as Tsinghua, BBEF, Communicate Technology Inc. was established,and with the DTMB system adopting Chinese 8MHz bandwidth,participated in the comparison test organized by the Cuban Ministry of Information with the European DVB-T standard system. The exciters, transmitters, measuring instruments, the antenna system and set-top boxes used in the test are all Chinese DTMB standard or domestic equipment and products. The test results show that the receiving level margin of Chinese standard is better than that of European standard in 41 points, accounting for 49.4%of 83test points that are normal in receiving, and the performance of two standards are the same in 29 points (accounting for 34.9%); the receiving level margin of European standard is better than that of the Chinese standard in 13 points (accounting for 15.7%).

 
The Cuba’s technical experts believed that the test results shows that the performance of Chinese standard is better than that of European standard, meanwhile,they requested China side to provide a 6M system meeting the using habits of Cuba as soon as possible. Under the support of Zhongguancun Administrative Commission, the Industry Alliance has only spent three months to provide a new DTMB system with 6MHz band width suitable for the South America.
 
From May 11 to June 9, 2009, at the invitation of Cuba Ministry of Information, the test group went to Havana again to participate in the comparison test with the European DVB-T standards, Brazil SB-TVD standard (i.e., a modified version of the Japanese ISDB-T standard). In a total of 70 test points, excluding two invalid points, 68 points are valid.There are 67test points at which the Chinese DTMB standard is ranked the first(98.5%), and 1 point at whichDTMB is ranked the second (1.5%).TheCuba’s technical staff and officials, including 2 Ecuador’s technical officials made a special trip to Cuba to observe the testing process,have no doubt on the advancement of Chinese DTMB standard. The following are the charts and pictures associated with this test.
 
Parameters of system being tested
  Subcarrier Code rate Guard interval Modulation Bandwidth Transmission rate Transmission power
DTMB 4K 0.6 1/9 64QAM 6MHz 18.274Mb/s 500W
DVB-T 8K 2/3 1/32 64QAM 6MHz 18.006Mb/s 500W
SB-TVD 8K 3/4 1/8 64QAM 6MHz 18.255Mb/s 500W
Test results
  Fieldstandard tests at 68 points Outdoorhousehold antenna test at 58 points  Attack test of 15 indoor interference items  for  5 times
Excellent Better in average Excellent Better in average
DTMB 67 2/10dB 56 6/12dB Chinese standard is better than European and Brazil standard
DVB-T 1 1/9dB 2 1/10dB
SB-TVD 0 / 0 /
 




2) In Venezuela
From June 8 to 27, 2008,the test team led by Beijing Haier,and participated by the units such as Tsinghua, BBEF, Communicate Technology Inc. went to Caracas,the capital of Venezuela,to attend the comparison test of Chinese, Japanese, and European standards. The test includes indoor, outside fixed reception, outdoor mobile reception, and anti-interference reception to household electrical appliances and anti-interference reception to motorcycle. The test was hosted by the Venezuela side, and Cuban experts participated in the entire process, and the European Union and Japan all sent the delegations of officials to attend the test. The total test results are: Chinese standard is better than Japanese standard (4:1)and the European standard (5:0). The following are the charts and pictures associated with this test.
 
Parameters of system being tested
  子载波
Subcarrier
码率
Code rate
保护间隔
Guard interval
调制
Modulation
带宽
Bandwidth
传输速率
Transmission rate
发射功率
Transmission power
DTMB 4K 0.6 1/9 64QAM 6MHz 18.274Mb/s 500W
DVB-T 8K 3/4 1/8 64QAM 6MHz 18.662Mb/s 500W
ISDB 8K 3/4 1/8 64QAM 6MHz 18.255Mb/s 500W
Test results

Ø Fixed receiving level margin: in a total of 32 test points, the Chinese standard defeats the European standard in 32 points, and defeats the Japanese standard in 28 points 
Ø Mobile reception time ratio: Japanese standard is about 80%, Chinese standard is about 60%, and the European standard is about 20%
Ø Depth of indoor reception: Chinese and EU standards are better than Japanese standard
Ø Indoor anti interference ability to household electrical appliances: Chinese and Japanese standards are better than the European standard
Ø Outdoor anti interference ability to motorcycles: Chinese and Japanese standards are better than the European standard
 

3) In Peru
From October 8 to December 4, 2008,the Chinese digital television test group led by Beijing Haier,and participated by the units such as Tsinghua and BBEF attended Chinese DTMB standard comparison test in Peru. The comparison tests were performed in Lima in the beaches, Iquitos in the tropical rain forest, in the plateau of Cuzco above 3 kilometers which have the greatly different television receiving conditions, and performed SD,HD and mobile TV comparison tests. The tests set the records of Chinese DTMB standard in the test time, test sites, test items in Latin America. Test results shows that the Chinese standard is ranked the first, exceeding the similar standards of the United States, Europe and Japanese. The following are the charts and pictures associated with this test.
 
 
Parameters of system being tested
  Subcarrier Code rate Guard interval Modulation Bandwidth Transmission rate Transmission power
ATSC /   / 8VSB 6MHz 19.390Mb/s 1000W
DTMB 4K 0.6 1/16 64QAM 6MHz 18.274Mb/s 1000W
DVB-T 8K 3/4 1/16 64QAM 6MHz 18.662Mb/s 1000W
ISDB 8K 3/4 1/9 64QAM 6MHz 18.255Mb/s 1000W
Test results
 
Ø Lima:it belongs to the first group together with the standards of European and Japanese, and it’s better than the standards of the United States and Brazil
Ø Cuzco: it belongs to the first group together with the European standard, and it’s better than the standards of the United States, Japanese and Brazil
Ø Iquitos: it is ranked the first, and it’s better than the standards of Europe, Japanese, the United States and Brazil

 

4) In Ecuador
 
At the end of June 2009, the Chinese standard test delegation led by China Potevia, participated by the units such as Tsinghua and BBEF attended the standard comparison test in Ecuador. The test lasted more than 20 days, and the test results showed the Chinese standard is far superior to Japanese - Brazil standards: in a total of 94 test points (83 outdoor test points, 11 indoor test point), the Chinese standard is better than Japan - Brazil standards in 31 points, worse than Japan - Brazil standard in 1 point, and they keep the same level in other points. The following are the charts and pictures associated with this test.
 
Parameters of system being tested
  Subcarrier Code rate Guard interval Modulation Bandwidth Transmission rate Transmission power
DTMB 4K 0.6 1/9 64QAM 6MHz 18.274Mb/s 500W
ISDB-SB 8K 3/4 1/8 64QAM 6MHz 18.255Mb/s 500W
测试结果 Test results
  83 outdoor test points 11 indoor test points
Failing to receive normally Excellent Failing to receive normally Excellent
DTMB 9 20 0 2
ISDB-SB 29 1 2 0