How to Measure Adjacent Channel Power with a Spectrum Analyzer?

Feb. 23, 2024

Adjacent channel power, as the name suggests, measures the power of the left and right channels (also known as upper and lower channels) adjacent to the transmitter's working channel. The smaller the power leakage of the carrier channel measured in the adjacent channel, the better the performance. Excessive energy leakage into adjacent channels will cause interference to adjacent operating systems and affect the normal communication of adjacent channels, so adjacent channel power is an important index to evaluate the performance of transmitters.

The adjacent channel power function of the spectrum analyzer is used to measure and analyze the power characteristics of the signal in a specified frequency range. The measurement of adjacent channel power can help us quickly locate the maximum and minimum value of signal strength, to carry out leakage detection, interference analysis, communication debugging, and other work. When we need to know the power distribution characteristics of the signal in a certain frequency range, we can use the adjacent channel power function to measure.

Below is the introduction to how to use spectrum analyzer SA9232 and RF signal generator TFG3836 to measure adjacent channel power.

Set the central frequency of the spectrum analyzer according to the generator output frequency.

To enter the adjacent channel power function, you need to press【MEAS】,select【ACP】

Set the adjacent channel frequency offset and bandwidth according to the requirements, up to 6 adjacent channels.

ACP Measurement 

Fig 1. ACP Measurement