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Do you know which phones currently support the Wi-Fi 7 protocol? People who ignore mobile phone launches may still not know. In case you don't know, popular phones such as s23ultra, Xiaomi 13 series, and Honor Magic5 series support Wi-Fi 7 protocol, but there is not much publicity, and they are not even mentioned on the product details page. Which Phones Currently Support Wi-Fi 7? How Do You Know A phone That Supports Wi-Fi 7? It is currently very simple to determine whether a mobile phone supports the Wi-Fi 7 protocol. Here is how: If the mobile phone "SoC" is Qualcomm Snapdragon 8 Gen2 or MediaTek Dimensity 9200 or above, it supports the Wi-Fi 7 protocol but may require an OTA upgrade to the system version. When mobile phones first supported the Wi-Fi 6 protocol, various manufacturers worked hard to promote it, but now it is Wi-Fi 7's turn; why is there no aggressive promotion yet? Why is Wi-Fi 7 Not Yet Popular? On the one hand, there are too many selling points of mobile phone technology now, and the technical upgrade of Wi-Fi is already weak. Another reason may be the implementation of Wi-Fi 7. In early June 2023, the Chinese Ministry of Industry and Information Technology only solicited approval opinions for Wi-Fi 7 equipment, which ended on July 1. Therefore, the solicitation for Wi-Fi 7 equipment approval opinions ended in less than two months and has not yet been implemented in China. For example, Xiaomi's 10G router has reserved space for Wi-Fi 7 in its hardware, but it is also waiting for the full implementation of the policy before it can be supported through subsequent updates. What Is Wi-Fi 7 And How is It Better Than Wi-Fi 6? Although Wi-Fi 7 has not yet become popular, this is just the right time to introduce the relevant knowledge of Wi-Fi 7 to all. 1. Technical Improvements of Wi-Fi 7 Over Wi-Fi 6 Wi-Fi 7 is the 7th generation Wi-Fi network technology. The technical standard is the aforementioned "IEEE 802.11be". On the official website of the Wi-Fi Alliance, it is shown that the standard "IEEE 802.11be" is being improved. Due to the development of VR, metaverse, remote office, 4K video, and other applications, network requirements have further increased. Wi-Fi 6 can no longer meet these applications' data transmission speed and network delay requirements. Therefore, IEEE and Wi-Fi Alliance are rapidly promoting the development of Wi-Fi 7. How Does Wi-Fi 7 Compare With Wi-Fi 6? The figure below compares the technical standards of Wi-Fi 7 and Wi-Fi 6. Compared with Wi-Fi 6, the maximum transmission speed of Wi-Fi 7 can reach 46Gbps, nearly five times that of Wi-Fi 6. Wi-Fi 7 will support more frequency bands, including 2.4GHz, 5GHz, and 6GHz. Before this, Wi-Fi 6 supported two frequency bands: 2.4GHz and 5GHz. Similarly, Wi-Fi 6E only supported the 6GHz frequency band (Wi-Fi devices are intended for compatibility with the following). However, due to frequency band allocation issues in different regions, the 6GHz frequency band supported by Wi-Fi 7 will be different. For example, the United States, South Korea, and Brazil have allocated the entire 6GHz frequency band (5.925 - 7.125GHz) to Wi-Fi 6E and Wi-Fi 7. Some countries have allocated the 6GHz low-frequency band (5.925 - 6.425GHz) to Wi-Fi and the remaining frequency band (6.425 - 7.125GHz) to IMT (International Mobile Communications, including 5G/6G systems), such as within the European Union, Japan, and Australia among many other countries. Considering the future 5G and 6G development, China has allocated the 6.425-7.125GHz frequency band to IMT. Therefore, this frequency band will not be used for Wi-Fi, and the 6GHz low-frequency band (5.925-6.425GHz) has also not been allocated to Wi-Fi. This move temporarily leaves room for subsequent development. In other words, China Wi-Fi 7 may not ultimately support the 6G frequency band. This can be confirmed by the frequency band given in the Ministry of Industry and Information Technology’s request to approve Wi-Fi 7 equipment. Due to the lack of the 6GHz frequency band, there are insufficient spectrum bandwidth resources to accommodate the 320MHz channel. Therefore, Wi-Fi 7 devices in China can only support the 240MHz channel, and the maximum transmission speed is also limited to 30Gbps. In theory, it can meet the needs of the metaverse, VR, remote office, 4K video, and other applications. In wireless transmission, the basic channel is 20MHz. If wireless transmission is compared to freight, 20MHz is the basic single lane. To increase the speed of freight, two adjacent 20MHz are merged into a dual lane, which is a 40MHz channel. By analogy, there are 80MHz channel and 160MHz channel. Wider channels allow for higher information transmission capabilities. Taking the above figure as an example, the 2.4GHz band only has three consecutive non-overlapping 20MHz channels, of which two consecutive non-overlapping 20MHz channels can be bound to 40MHz channels (this is usually not recommended in the 2.4GHz band). The 5GHz band has up to 13 consecutive non-overlapping 20MHz channels and supports up to 160MHz channels under the Wi-Fi 5 and Wi-Fi 6 standards. The 6GHz spectrum bandwidth resources are abundant. So, it can support 320MHz channels. Even in the case of 6G spectrum division in the United States, there are 1200MHz spectrum bandwidth resources. The modulation method, Wi-Fi 7, has also been improved, supporting 4096QAM, which means that the information supported by each modulation symbol has been increased from the previous 10bit under 1024QAM modulation to 12bit, and the amount of data transmitted is more. In addition, the number of Wi-Fi 7 spatial streams has also been expanded from 8 to 16 in Wi-Fi 6, which means that one AP can transmit data to 16 receivers simultaneously (one STA can have multiple receivers). The spatial streaming speed is increased by two times. The above are the technical upgrades of Wi-Fi 7 compared to Wi-Fi 6. There are also three new technical highlights on Wi-Fi 7 to enable devices to transmit data faster and more stably under the Wi-Fi 7 protocol. 2. Multi-link Transmission Technology (MLO) Of Wi-Fi 7 On previous Wi-Fi 6 devices, although two frequency bands are provided, 2.4GHz and 5GHz, the device can only transmit on one frequency band when transmitting data. If conditions change, it will jump to another frequency band for transmission. The process is shown on the left side of the picture below. The multi-link transmission of Wi-Fi 7 can transmit data in two frequency bands simultaneously. This is shown on the right side of the figure above, and the transmission modes are divided into two. One is multiple transmit and single receive. The AP simultaneously sends the same data to the receiving end in multiple frequency bands (2.4GHz, 5GHz, 6GHz). The system automatically selects the data in the fastest frequency band. If the frequency band is interfered with, the system accepts other data. Frequency band data. This method can improve the stability of data transmission. Another mode is multi-send and multi-receive, splitting one piece of data into three parts and sending them simultaneously through three frequency bands. The receiving end combines the data after receiving it. Multi-send and multi-receive modes can increase the speed of data transmission. 3. Comparison of Multiple Resource Units (MRU) IN wI-fI 7, Wi-Fi 6, and Wi-Fi 5 On Wi-Fi 5, each channel can only send information to one receiving end per unit of time. To improve the utilization of Wi-Fi 6, the Resource Unit (RU: Resource Unit) is introduced. Through Orthogonal Frequency Division Multiple Access (OFDMA) technology, the 20MHz channel can be divided into 256 subcarriers and 242 effective subcarriers. The Wi-Fi Alliance stipulates that the minimum resource unit is 26 subcarriers. Therefore, the effective subcarriers of RUs within a channel can be 26 (26-tone RU), 52 (52-tone RU), 106 (106-tone RU), and 242 (242-tone RU). In the Wi-Fi 6 standard, the Wi-Fi Alliance specifies the number of subcarriers in a RU, mainly including 26-tone RU, 52-tone RU, 106-tone RU, 242-tone RU, 484-tone RU, 996-tone RU, 1992-tone RU, one user can only correspond to one RU. Wi-Fi 7 supports a multi-resource unit (MRU: Multi-RU). One user can correspond to a combination of multiple RUs, such as a 26-tone RU and 52-tone RU or a 484-tone RU and 996-tone RU combination. For example, there are three users using 20MHz at the same time. One user is assigned to a 106-tone RU, and the other two are assigned to a 52-tone RU. The remaining 26-tone RU can be reassigned to the former to receive two RUs. , reaching 106-tone RU +26-tone RU, improving resource utilization and information transmission speed. Categories of Wi-Fi 7 RUs Not any RU can be combined. The Wi-Fi 7 protocol divides RU into two categories: Small part RU: 26-tone RU, 52-tone RU, 106-tone RU; Obe RU: 242-tone RU, 484-tone RU, 996-tone RU, 1992-tone RU. The Wi-Fi Alliance stipulates that only RUs of the same type can be combined, small RUs can be combined with small RUs, and large RUs can be combined with large RUs. For example, the 1992-tone and 996-tone RU are equivalent to 160MHz and 80Mhz channels. Don't Miss: Reasons to Surf The Internet with A Wi-Fi Hotspot Instead of Your Phone's Mobile/Cellular Data The difference between WiFi4, WiFi5, and WiFi6 Network Standards Preamble Puncturing Technology The purpose of preamble puncturing technology is the same as that of multi-resource units, which is to improve channel utilization. However, preamble puncturing is more used to restore channel utilization in the event of interference. As mentioned in the previous channel section, the basic channel is 20MHz. Through channel bundling, 40MHz channels, 80MHz channels, and 160MHz channels can be formed. However, bundling can be divided into main channels and auxiliary channels. The allocation principle is as follows: Main channel 20MHz and 20MHz combination: 20MHz (main) + 20MHz (auxiliary); Combined into the main channel 40MHz and then combined: 40MHz (main) + 40MHz (auxiliary); Combined into the main channel 80MHz and then 80MHz (main) + 80MHz (auxiliary). Before Wi-Fi 7, once the auxiliary channel in the combination was interfered with, it could not be combined into a wider main channel. For example, if the 20MHz auxiliary channel was interfered with and could not be combined with the 20MHz main channel, then the remaining 40MHz auxiliary channel and 80MHz auxiliary channel could not be combined or used. This results in a waste of channel resources. Preamble puncturing solves this problem. It can shield the interfered 20MHz auxiliary channel without affecting the main channel to form a wider channel. The 20MHz main channel can still be combined with the 40MHz auxiliary channel to form a 60MHz channel, then with the 80MHz auxiliary channel to form a 140MHz channel. Channel. Preamble puncturing greatly improves the anti-interference ability of information transmission, and information can still be transmitted quickly, even in an interference environment. 5. Summary And Conclusion The above is about the related technologies of Wi-Fi 7. Multiple technical upgrades make it faster, lower latency, and more stable. According to Huawei’s previous test with Xiaomi 13 Pro, Xiaomi 13 Pro, which supports the Wi-Fi 7 communication protocol standard, has a transmission speed of 4.3Gbps in the Wi-Fi 7 environment. It is two times that of the Wi-Fi 6 environment. In addition, the delay is within 4ms, while the delay in the Wi-Fi 6 environment is about 10ms. Mobile phone and router manufacturers have reserved room for upgrades to Wi-Fi 7 but are unwilling to promote it too much. After all, the promoted functions differ from subsequent standards, which becomes false propaganda.