Networking. Frequency Bandwidth: 20MHz vs 40 MHz vs Auto. We have two wireless AP's in the house, one is from the ISP provided router and one is a WiFi repeater. Our area isn't congested, though there are times when two of my neighbors' AP's pop up randomly. In theory, 40Mhz has twice the channel bandwidth compared to 20Mhz, and the theoretical data transmission rate is also twice as high; However, from a practical application perspective, setting a higher bandwidth has a greater chance of conflicting with surrounding WiFi signals, which can affect the actual data transmission rate. .

difference between 20mhz and 40mhz bandwidth