Wireless Data Frequency Ranges
Wireless data transmission is used in cases where the arrangement of wired or fiber optic communication channels is not physically possible, or if existing wired communication channels do not satisfy consumers in terms of information transfer speed, or their use is economically impractical. Equipment for wireless connections can be classified by radio frequency parameters, the main of which is the radio frequency range in which this equipment operates. The range in which the equipment operates depends on such indicators as communication range, information transfer rate and line-of-sight requirements, dependence of communication quality on weather conditions. The dependence of the parameters is as follows: the higher the frequency, the higher the data transfer rate, the shorter the range, the higher the line of sight requirements and the greater sensitivity to weather change.
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2022: Open "new dimension" for wireless data transmission, speed - 1 TB/s
On February 10, 2022, Chinese researchers announced that they had managed to achieve record data rates using revolutionary technology that could help China take the lead in the global race for next-generation 6G wireless communications.
Using vortex millimeter waves (a range of radio waves with a wavelength of 10 mm to 1 mm, which corresponds to a frequency of 30 GHz to 300 GHz), the researchers transmitted 1 TB of data at a distance of 1 km in 1 second. The wireless link, installed in January 2022 at the Beijing Winter Olympics complex, can simultaneously broadcast more than 10 thousand high-definition live video channels, said a team led by Professor Zhang Chao from the Tsinghua University School of Aerospace Engineering in Beijing.
According to Zhang and his colleagues at Shanghai Jiao Tong University and China Unicom, vortex waves, unlike anything created in the field of radio communications over the past century, have added "a new dimension to wireless data transmission."
According to them, the experiment showed that China "leads the world in research on potential key technologies for 6G."
Existing mobile devices use electromagnetic waves for communication, which propagate like ripples in a pond. The information is represented by the "rise and descent" of these waves, which, from a mathematical point of view, have only two dimensions.
The vortex electromagnetic wave has a three-dimensional shape similar to a tornado. Additional information may be encoded in the vortex motion, or orbital angular momentum, of these waves to significantly increase communication capacity.
The rotational potential of radio waves was first reported by British physicist John Henry Poynting in 1909, but it was not easy to use it.
Zhang and colleagues said their breakthrough was based on the hard work of many research groups around the world over the past few decades.
The main problem is that the size of the rotating waves increases with distance, and attenuation of the signal makes high-speed data transmission difficult.
The Chinese team created a unique transmitter to generate a more focused vortex beam, causing waves to rotate in three different modes to transmit more information, and developed a high-performance receiver capable of receiving and decoding a huge amount of data in fractions of a second. According to scientists, they "defeated" physics and proved the effectiveness of data transmission using vortex radio waves.[1]
The following frequency bands are most common:
136 - 174 MHz
The data rate in this range reaches 19.2 kbps, the communication range is up to 50-70 km, communication can be carried out "due to the angle" and beyond the horizon by curving the path of the beam at the ground. Communication parameters are practically independent of weather conditions. Waves of this frequency are called ultra-short (VHF) and are used for broadcasting radio stations. Frequency is also used in portable radio stations and radios.
400 - 512 MHz
This range provides data transmission at a speed of up to 128 kbps, the communication range can reach 50 km. Radio communication is possible by receiving signals reflected from various buildings and structures, mountains and other objects, although line of sight is desirable. The waves of this frequency are called decimeter (DC).
820 - 960 MHz
This frequency band is used by the GSM-900, DUMPS and CDMA mobile communication standards. The data rate reaches 2 Mbps.
2.4 GHz
The ultra-high frequency of 2.4 GHz (microwave) has become widespread in information technologies created today. This frequency is used in devices using GPRS, Wi-Fi, WiMAX and Bluetooth. The data rate reaches 54 Mbps. It is curious that waves of the same frequency are used in microwave ovens in cooking.
5 GHz
Some versions of WiMAX and Wi-Fi technologies use a frequency of 5 GHz for data transmission. The data rate on Wi-Fi equipment of this frequency also reaches 54 Mbps.
There are others that have not yet received the same wide distribution of radio frequency ranges.
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