In QAM, what is the difference between the power spectral density of different binary modulation signals?

QAM uses two independent baseband signals to suppress the amplitude modulation of two mutually orthogonal co-frequency carriers, and uses the orthogonality of the spectrum of this modulation signal in the same bandwidth to realize the transmission of two parallel digital information. This modulation method usually includes binary QAM(4QAM), quaternary QAM(l6QAM), octal QAM(64QAM) and so on. Their differences are as follows:

1, the corresponding spatial signal vector endpoint distribution map is called constellation map, with 4, 16, 64… vector endpoints respectively.

2. The relationship between series M and signal state M is applicable to 4QAM, 16 QAM, 64QAM and so on.

Extended data:

QAM analyzer:

QAM analyzer is a comprehensive solution for RF installation and maintenance, which is used to test DVB-C (Cable Digital Video Broadcasting) signals on cable TV systems. It provides engineers with the measurement function needed to accurately check the quality of service delivered to users. All the measurements are easy to access, and the measurement results are displayed in clear graphics.

Application:

Front-end equipment installation and maintenance;

System check;

Field installation and maintenance;

Modulator production or acceptance test;

Modulation test in optj 9 1-6 MHz channel bandwidth.

References:

Baidu encyclopedia-orthogonal amplitude modulation