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Tiếng Việt What is phone frequency band?
What is phone frequency band? Phone frequency band is the concept that refers to the frequency of electromagnetic waves used to transmit and receive communication signals between phones and wireless technologies. As of today, there are 3 mobile phone frequency band technologies: 2G (GSM / EDGE); 3G (UMTS / HSPA), 4G (LTE / 4G LTE).
Phone frequency band is very important when traveling abroad
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When reading a phone's specification sheet or the 3G/4G frequencies announced by carriers, you will often see lines like 800 / 850 / 1700 / 1900 / 2100 / 2600 MHz. These are the 3G/4G frequencies that carriers are providing. Only phones with matching frequency bands can connect.
3G frequency band is the range of frequencies that carriers provide for devices to connect to the 3G mobile network. The current 3G frequency bands worldwide are 850/900/1800/1900/2100 MHz.
4G frequency band is the range of frequencies that carriers provide for devices to connect to the 4G LTE mobile network. The LTE standard is used in many different frequency bands depending on the region. In North America, the frequency bands 700/800/1700/1900 MHz are designated for LTE. In Europe, the 4G frequency bands are 800/1800/2600 MHz. 4G LTE frequency bands in Asia have 2 ranges: 1800 and 2600 MHz.
Frequency bands are very important because if your phone does not match the frequencies provided by the carrier, it will not be able to receive signal.
3G/4G frequency bands of carriers in Vietnam
In Vietnam, carriers provide mobile services on 2 frequency bands: 900 / 1800 MHz. All mobile telecommunications service providers in Vietnam have agreed to choose the 1800 MHz band for 4G LTE networks. Therefore, most current phone models can connect.
If a phone is imported from abroad, such as Japan or the US, it must be unlocked to be used. However, even after unlocking, the 4G connection capability is still weaker than international version phones.
Phones officially sold in Vietnam are international versions with 2-4 frequency bands. Therefore, they are not locked by carriers. You can choose a SIM from Viettel, Vinaphone, or Mobifone to use with your phone.
4G frequency bands in Vietnam
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3G/4G frequency bands in countries around the world
When buying a phone, you need to pay attention to its origin. Phones originating from Europe can all use 4G in Vietnam. This is because EU countries have chosen 900, 1800 MHz frequency bands as the standard. Meanwhile, if the origin is from North America or Asia, you need to check the frequency band carefully. This is because carriers in the US only use 700 / 850 / 1700 / 1900 MHz bands. As for Japan, it licenses LTE at 1500 MHz, 1700 MHz, and 2000 MHz bands. Some other Asian countries use 2100 MHz or 2600 MHz frequencies... Or like China, 3G can only be used for domestically manufactured phones.
The fact that carriers in different countries use different frequency bands makes it difficult to connect to 3G/4G networks when traveling. If your phone does not match the mobile frequency provided by the carrier, you will not be able to get a signal. This is a common case when Vietnamese people buy SIM cards in Japan, France, or China to use in their phones while traveling.
The most accurate way to check mobile phone frequency bands
Turn on your phone and open the dialer. Then, press the code *#06# to display the IMEI sequence. Enter this IMEI number on imei.info to see the frequency bands your phone supports. Then, check the country you are going to visit to see if it supports your phone's frequency bands.
The most accurate way to check phone frequency band
Another way is to check the phone specifications from mobile retailers like The Gioi Di Dong, FPT, Cellphone... to know your phone's frequency bands. Note that even if your phone supports 4G LTE, it must be enabled to be used. For example, if your phone can use 4G but is set to 3G, it will not appear.
iPhone frequency band check results
This is the most accurate way to check the frequency bands of iPhones and Android phones. You can check the frequency bands of Android phones like Samsung, Sony, HTC, and iPhones in just 1-2 minutes.
How to choose a mobile phone suitable for international travel
Currently, most phones support at least 2 frequency bands. Many new phone models even support 4 frequency bands. You should choose a quad-band phone to use 3G/4G worldwide. Quad-band phones include iPhone, Samsung, Sony, Nokia... With a quad-band phone, you can travel internationally without worrying about signal loss. However, make sure you buy an international version, not a network-locked version or one for the domestic market. When traveling abroad, you just need to buy an international SIM card and insert it to use without any further setup.
So you already knowwhat phone frequency bands are andhow to check your phone's frequency bands. Apply it now to find out which frequency bands your phone has and if it can be used abroad.
