The speed of the mobile phone is limited by the baseband, antenna and network operator. Three factors are indispensable. The baseband is basically the world of Qualcomm. Qualcomm has inserted Cat.12 support on the X12 LTE baseband of Snapdragon 820. Domestic operators have just entered the so-called 4G+era (mobile phones only need to support Cat.6). However, antenna design (several X several MIMO antennas refer to this) has been ignored by many companies.

The latest news on August 11 shows that the newly released Note7 is the first equipment For a 4 × 4 MIMO commercial mobile phone, 4 × 4 MIMO actually uses four antennas at the same time to keep connected to the base station, which is equivalent to opening four "flow pipes" at one time, The network connection speed can be doubled, and the principle is similar to the following figure:

Although the machine is limited to Cat.9， But in theory With the X12 LTE baseband of Snapdragon 820, the download speed can reach 600Mbps (LTE Cat. 12) and upload speed can reach 150Mbps (LTE Cat. 13). Another problem is that, Currently, BTSs generally only support two connections, and many home routers have just had a 3 * 3 MIMO design. So even though Note7 supports this technology, the BTS cannot provide "4-way connection" at the same time.

Another detail is that Exynos 8890 does not support this technology because it does not have this baseband chip from Qualcomm.

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