Spectrum Analysis (+Signal Generation)
In this section we will have a closer look at how spectrum analysers operate, including the generation of microwave signals.
Lecture slides on signal generation/synthesis.
Lecture slides on spectrum analysis.
Our second lesson test is on the topics Microwave synthesis and Spectrum analysis. This time we split this test into two parts, a) on synthesis and b) on analysis, to be taken in two separate contact sessions.
Prepare for the a) part by reading Chapters 3 (p. 41-62) in the main course book. In essence Chapter 3 discusses reasons why a frequency synthesiser never outputs a pure sine-wave tone, but something like shown in Fig. 3.1 in the course book. Additionally to this you should understand why the combination of direct digital and indirect synthesis, illustrated in Fig. 3.16, is so advantageous.
This lesson test is held as part of the lecture. First, answer all the questions individually within 10 minutes. Then (after the lecture), the teacher will assign you to breakout rooms in Zoom where you answer the same questions again in small groups, and you choose one group member who puts the answers, i.e. you need to agree on the answers (this second attemp will not count unless done as a group). With the (second) "group" attempt students can improve their evaluation by up to 50 % of the points available in the first attempt, i.e. the assessment weight of the first attempt is two thirds, and of the group attempt one third (for this lesson test).
Our second lesson test is on the topics Microwave synthesis and Spectrum analysis. This time we split this test into two parts, a) on synthesis and b) on analysis, to be taken in two separate contact sessions.
Prepare for this part b) by reading part of Chapter 4 (p.64-69) in the main course book. The goal of reading Chapter 4 is to recognise and recall the function of the super-heterodyne principle used in traditional spectrum analysers illustrated in Fig. 4.1 and it is essential to understand the role of the RBW filter in terms of the dynamic range of the instrument. It is also useful to understand the technological limitations of the real-time spectrum analysers. Additionally, it is recommended to read Section 2.3 of the R&S Educational Note attached below, or Sections 2.3-2.5 (p. 75-106) in the third text book can be read alternatively.
This lesson test is held as part of the lecture/regular session. First, answer all the questions individually within 10 minutes. Then (at the end of the session), the teacher will assign you to groups in which you answer the same questions again, and you choose one group member who puts the answers, i.e. you need to agree on the answers (this second attemp will not count unless done as a group). With the (second) "group" attempt students can improve their evaluation by up to 50 % of the points available in the first attempt, i.e. the assessment weight of the first attempt is two thirds, and of the group attempt one third (for this lesson test).
This is a useful educational note on "Measuring with Modern Spectrum Analyzers" provided by Rohde&Schwarz
This external link to a supplementary video is purely for your information. It illustrates the limits of digital processing and the trend towards "simply" A-to-D converting the complete RF input signal instantaneously across the whole instrument bandwidth and using FFT to create/analyse the spectrum. This is a very interesting engineering video, which is why we included this link here.