【Technical Blog】Wi-Fi Speed Brief Introduction

Hi~ I ‘m Wi-Fi Speed~ Nice to meet you~

Electromagnetic waves are transmitted at a fixed speed of light, so scientists use electromagnetic waves to produce various changes to transmit information. I’m not like the speed of a vehicle, but I, the Wi-Fi speed, means how many information I can transmit by electromagnetic waves.

For example, I’m using a car with a fixed speed to transport as much packet as possible.

In order to protect the packet from being damaged, many protective covers will be used. But in order to transport as much as information, I need to remove the protective covers and use some ways to packet the information. Thus, various nouns are generated.
1. From CCK to OFDM, from 64QAM to 1024QAM, etc., we use various methods to carry out more information.
2. From HT20 to HT160, the car is designed to be wider and wider to occupying multiple lanes.
3. From one antenna to multiple antennas, the carriage is then stacked on another carriage.
The above result is the dazzling rates, as shown in the following table:

The more information carried; the more information lost. So how to balance reliability and efficiency in the process of data transmission?

• I need more antennas, higher information compression ways to carry more information.
• The signals are affected by obstacles and distances. A proper distance can help me to transport the information reliably.
• Compared with wired transmission, wireless transmission shares the same channels with others, so:
  

• I need to follow the rule and wait to pass. As a result, the actual rate will only 70% percent of the maximum rate. For example, a dual antenna 11ndevice claims a maximum speed of 300 Mbps, but the actual speed is only about 210 Mbps.
  

• The more users connected, the longer the time I need to wait, and the speed rate will become slow. So, it would be better to have a reasonable balance plan to get the best negotiation rate.
• Compared with HT20, HT40 means that it occupies more channels, and the probability of interference is greatly increased, which requires a reasonable deployment configuration.
  

In the end, in order to reach the best negotiation rate, the network experience may be affected.