what is the wave analyzer in this artical? How to get Eb/No?

In order to mearsure the Eb/No, I need to get the noise power density. In this application notes, it says the No can be measured by wave analyzer, does it mean a spectrum analyzer? But how extractly to do that? I did use spectrum analyzer to examine the BPSK signal, its something like the attached pic, I cann't figure out where is the noise floor because the noise floor is not flat, it will is higher when the freq is more close to the carrier freq. So how to get the noise power density?

The application note can be download from here:

http://rfwireless.rell.com/pdfs/TN_WJpsk2.pdf

The application note can be download from here:

http://rfwireless.rell.com/pdfs/TN_WJpsk2.pdf