Wi-Fi transmits information in packets of data, which in turn consist of symbols, each encoded with several bits.<\/p>\n\n\n\n
The modulation symbol is a phase and sample code of the signal generated by changing the high frequency carrier frequency, which can then be bit-sequenced or demodulated by the receiver, for example, a 16QAM symbol encodes 4 bits in each symbol. Thus, 4 bits are transmitted with each symbol transmission and decoding. At the same time, however, the 1024 QAM symbol transmits 10 bits, i.e. such a symbol must be able to differentiate with respect to the state of the 1024 different signals.<\/p>\n\n\n\n
To identify a symbol, a setting signal is added in front of each symbol, which allows the beginning of the symbol to be identified. With a long symbol and, if necessary, a longer setting signal, a larger coverage area is achieved.<\/p>\n\n\n\n
The video shows that the length of the symbol has changed with the advent of the Wi-Fi 6 standard from 3.2 microseconds to 12.8 microseconds. It now depends on the modulation how much information each symbol contains, but simple math says that a long symbol and preamble are easier to identify and demodulate in a reflective and noisy environment, so distances increase significantly.<\/p>\n\n\n\n
Watch the video for more details.<\/p>\n\n\n\n