AppleiPhoneThe XS/XS Mx/XR mobile phone has been released for a whole month. It has been on the market for a while. The voice of the Tucao is much less expensive. The choice now is to buy or not to buy, do not buy, continue to spit, buy It has already been used, but there are many problems with it, especially the signal problem of the new generation iPhone. The signal problem of iPhone XS/XS Max is somewhat metaphysical. Some people use it without any problem. Some people use the discovery signal to be worse than the iPhone X. This problem has many explanations.IntelBaseband, butHuaweiThe engineer gave his answer, and the root cause of the iPhone XS/XS Max signal may be 4x4 MIMO. Apple used this technology to roll over for the first time.
The iPhone XS/XS Max signal is not well discussed. Whether it is personal experience or professional testing, the results given by many parties are not consistent. At first, everyone tends to think that it is Intel's baseband. After all, Intel's technology in this field. And experience accumulation is not as good as Qualcomm, but PCMag magazine has also done a professional test, that the Intel baseband uplink download is no problem, faster than Qualcomm baseband.
In addition to the baseband, there is also an analysis of the problem of radio frequency. On this issue, wiwavelength has done EIRP testing. The conclusion is that in the previous generation iPhone X, the Qualcomm baseband version and the Intel baseband version performed very consistently, and the iPhone XR signal performance was also better.
For the problem that the iPhone XS/XS Max signal is not good, I know that there is a Huawei antenna engineer who also did the analysis.HereProfessional analysis will not be described one by one. He analyzed three possibilities of poor signal - baseband, radio frequency and antenna. The first two parts may cause the signal to be bad, and the problem may be on the antenna:
"This year is the first time for the iPhone to do 4*4 MIMO. So it can be seen in the appearance that there are 2 more seams. In order to add 2 more antennas, upgrade from the original 2*2 to 4*4. Unfortunately It is so simple to increase the antenna without opening more slots. The isolation of the 4*4 MIMO antenna at the same frequency is very difficult to achieve. At the same time, the original antenna size will also become smaller, resulting in performance degradation. Now everyone only pays attention to the lte signal is not good, in fact, the top diversity, GPS / WIFI antenna performance is also worse."
Under this question, similar to his point of view, the answer from Skyworks' RF RF engineer is that the antenna design change has caused signal problems. Adding an antenna is not a place to install. The antenna's directivity is between the antennas. The isolation is an indicator that needs to be carefully designed during design.
For the problem of poor signal, Apple official has not yet concluded, but the antenna change is very likely to cause signal problems. The iPhone 4 mobile phone also had a signal difference due to antenna problems. In addition, from the existing tests, the signal is not good mainly due to the iPhone XS/XS Max. The iPhone XR performs normally in the wiwavelength test, and it has no 4x4 MIMO function, so the signal gate caused by the antenna is more A bit convincing.
However, the iPhone XR mobile phone signal is still the same as the iPhone XS/XS Max. This has to be a real machine experience. On the 19th of this month, iPhone XR officially accepted the reservation, and then waited for a while to know the result.