Technical Analysis: Comparison and Analysis of Carrier 3G Network Radiation

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To say 3G network, today's three major operators in China adopt different 3G network standards, China Mobile is TD-SCDMA, China Unicom is WCDMA, and China Telecom is CDMA2000. All three systems are based on CDMA technology. China Mobile and China Unicom's 2G era are based on the GSM network, while China Telecom is CDMA (1X). Mobile phone radiation has always been the focus of people's attention. Although people know that strong radiation will endanger health, what is the situation of mobile phone radiation? What is the difference in radiation between different network standards? Let's take a look.

Technical Analysis: Comparison and Analysis of Carrier 3G Network Radiation

GSM/CDMA transmit power requirements

First, we need to look at the difference in transmit power between GSM and CDMA networks under 2G networks, and understand their respective radiation conditions, and then further extend to 3G networks. From the requirements of CDMA and GSM related technical specifications for mobile phone transmit power, it can be known that the currently used GSM mobile phone 900MHz band has a maximum transmit power of 2W (33dBm), and the 1800MHz band has a maximum transmit power of 1W (30dBm). Higher power. At the same time, the specification requirements, for the GSM900 and 1800 bands, the emission intensity value comparison (unit: microwatts / square centimeter)

Not connected, connected to Unicom GSM network, maximum 411, average 352, maximum 393, average 285

Unicom WCDMA network

130 30

60 5

Telecom CDMA network

31 4

31 3

Telecom CDMA2000 network

In the network comparison between China Unicom and China Telecom, under the 2G network, China Unicom switched to the GSM network. Whether the dialing is not connected or connected, the bursting emission intensity will be relatively large, generally reaching a maximum of more than 400. When it is not turned on, its emission intensity is maintained at a high level, which is between 200-300. After turning on, the emission intensity is gradually reduced, but it is maintained at about 100-200.

Under Unicom's WCDM network, the emission intensity is greatly reduced, and the maximum value is maintained below 100, with an average of only 0-30. After the connection, the radiation can be neglected; China Telecom will automatically switch to CDMA 1X network, and it performs best. The maximum emission intensity is only around 30, and the emission intensity is only in the single digits, whether it is not turned on or turned on. Let's take a look at the comparison between Unicom and Mobile:

Emission intensity test

As mentioned above, the launch intensity of a mobile phone is related to the network design of the mobile phone in addition to the network environment. Vivo Xplay's strongest signal is at the bottom position. It is probably the place where the antenna is designed. Although it is not near the earpiece, it does not hurt the human ground. However, compared with the HTC One, the signal shielding needs to be strengthen.

Emission intensity comparison (unit: microwatt / square centimeter)

Not connected to the connected Unicom GSM network maximum 414 Average 335 Maximum 387 Average 310

Unicom WCDMA network

84, 34

65, 30

Mobile GSM network

421,350

340, 240

Mobile TD-SCCDMA network

54,13

45, 2

Speaking of the status of the network, China Unicom's GSM network is similar to the previous test. The emission intensity is not strong and the transmission is strong, with an average of more than 300. Under China Unicom's WCDMA, the emission intensity has been greatly improved, basically in line with the HTC One test, and the average can be maintained at a low level below 30 (a sudden situation of more than 100).

China Mobile's test is affected by the network environment. The status of the GSM network is basically the same as that of Unicom's GSM. It has reached a value of more than 300. Under the TD-SCDMA network, dial-up calls are automatically converted to 2G E-network bearers ( The Xplay signal is still displayed as H), so the emission intensity is similar to that of the GSM network. First of all, we speculate that although the TD signal is good in our location, the call bearer may be assigned by the E network, which causes the TD not to take the voice call line, so we found another TD signal to re-test, sure enough In the case of TD bearer calls, the transmission intensity will also drop significantly, even lower than WCDMA.

Summary: It can be seen from the test that although the three major operators adopt different network standards, their essence belongs to CDMA technology, so it has a larger radiation advantage than GSM network. We can determine that the GSM network is more radiant than the CDMA network in all aspects of the environment. Everyday, if we call 3G network, such as call, SMS, Internet access, etc., the radiation intensity will remain at a low level. Of course, CDMA still has advantages here, but compared with 2G network, the advantage of 3G era is not too obvious. .

However, we need to be aware that among the three major operators, China Mobile and China Unicom have made great progress in 3G coverage, but some network blind spots or weaker signals will still be converted to 2G E networks, where China Telecom The advantages of CDMA networks will be highlighted.

3G network radiation

In the 3G era, although the three major operators have adopted different network standards, they are not fundamentally different from CDMA technology, so the mobile phone's transmit power can be effectively controlled. In theory, the transmission power of TD-SCDMA, WCDMA and CDMA2000 are all at the same level, and the radiation can be greatly reduced.

We have already learned about the radiation situation of GSM/CDMA networks. In 2G networks, in most environments (assuming stable network signals and high base station density), CDMA networks are undoubtedly smaller than GSM networks in terms of transmit power and emissions. Under the 3G network, since the three major operators have adopted the CDMA technology standard, they can reduce the radiation of mobile phones. Having said that, China Mobile and China Unicom use the GSM network in the 2G era. Although after 3 years of network construction, the 3G network coverage and signals have been greatly improved, but there are still many blind spots or weak signals of 3G signals. Place, this will cause the phone to automatically switch to the 2G GSM network.

Because the technical systems of CDMA and GSM have different requirements on the transmit power of CDMA and GSM mobile phones, as well as the initial transmit power value and power control mechanism, the average transmit power of CDMA mobile phones is much lower than that of GSM mobile phones during communication. Transmit power. It can be seen from the test that the average transmission power of CDMA mobile phones is more than 500 times smaller than that of GSM mobile phones. Considering that GSM mobile phones are only transmitted within one eighth of the time, the energy of CDMA radiation is higher than that of GSM mobile phones in the same time. Smaller than 60 times.

CDMA technology is relatively "green"

In summary, China Telecom's 3G network coverage is relatively good. Regardless of the 2G or 3G network, the transmission power and radiation of calls and Internet access are small, and the coverage of China Mobile and China Unicom's 3G network still needs to be strengthened. The GSM network under 2G has strong radiation. Of course, this radiation intensity is still in the safe range, consumers do not have to worry too much, it is recommended to avoid long-term calls in the GSM network where the signal is weak.