Code division multiplexing
Frequency division multiplexing and time division multiplexing and wavelength division multiplexing is simple, no need to say,

Frequency division multiplexing waves with different frequencies, wavelength division multiplexing is one of the frequency division multiplexing and time division multiplexing is time apart, for you for a moment, a moment for me, also do not have what good say of,

Code division multiplexing is interesting,

How to deal with?

Is to give all a substrate using code division multiplexing of base station, and then in the substrate of any two substrate multiplication is 0, do what is the point?

We, for example,

A stand of code for: 00011011; B stand of code for: 11100000; Station C code is: 00000100 A * C=0; B * C=0; A * B=0

If A station to send 1, then A stand actually send information for: 00011011; If A station sends 0, then A station sends information actually is: 11100100, we consider code 00011011-1-1-1 1 1 1 1 1

Why do you do that? Slowly, don't worry, first I layers to open its mysterious veil,

This (1-1-1-1-1 of 1 1 1 * 00011011)/4=1 isn't it? Is this 1 we send 1? Yes

So (1-1-1-1-1 of 1 1 1 * 11100100)/4=1 isn't it? Is this - 1 0 we sent? Yes

Suppose the when A station sends A message Z, B site also sent A message X, C site also sent A message to Y, the three mixed messages up became Z + 11100000 * 00011011 * 00000100 * X + Y

So if we want to get A message, using the code division multiplexing calculated 00011011 * 11100000=0;=0, 00000100 * 00011011 is to filter out the information of X and Y,