Hi Feras,
RF spectrum analyzer allows the user to calculate and display electrical signals in the frequency domain. It can display the signal intensity, power spectral density and phase.
Using it we visualize graph of follwoing :
•Signal
•Noise
•Signal + Noise
•All
Where as The Electrical Carrier Analyzer (ECAN) measures and compares different results in two different frequencies. It can also calculate carrier to noise ratio.The ECAN will estimate the signal and the noise power for each electrical signal channel based on the central frequency of the internal filters. The analysis tab displays results such as frequency, power, noise, and SNR.
As both measure the results of two different parameters , so both having different values.