Error vector magnitude

Okay kiddo, so error vector magnitude (EVM) is basically a way to check how accurate a radio signal is. When we talk on our phones or send pictures, those signals get sent through the air using something called radio waves. And if those waves aren't good quality, our calls or pictures might not come through very well.

So, EVM helps us check if the radio waves are doing a good job sending our signals. Here's how it works: imagine you want to throw a ball into a basket. If you throw it perfectly, it will go right into the basket (kind of like a signal being sent perfectly without any errors). But if you don't throw it perfectly, it might go off to the side or too high or too low (kind of like a signal having errors or mistakes). EVM is like measuring how far away the ball landed from the basket, which tells us how big the mistakes were in our throw.

In the same way, EVM checks how much the radio signal is "off" from where it should be. It does this by comparing the ideal signal with the actual signal that gets sent. The bigger the difference between these two signals, the bigger the error vector magnitude. And if it's too big, it means our signal isn't very accurate and our call or picture might not come through very well.

So, just like how we want to throw the ball into the basket as accurately as possible, we want our radio signals to be sent as accurately as possible. That's why EVM is important!