2 Comments on “Tutorial 23b – Trellis coded Modulation (TCM)”

I really enjoy your tutorials, the ones that I have read have been extremely useful and a great compliment to the courses I’ve taken. Thanks. I probably wouldn’t have sent you this e-mail if it wasn’t for your Amazon comment under Richard Lyons Understanding Digital Signal Processing. I’m reading his book now, I’m glad you decided to spread your knowledge with the same writing style.

Going through your tutorial, I think I may have found some errors in your Figures. There may be an offset in the indexes that generated the calculations. My hand calculations don’t match your Figures, and the numbers used in the examples give calculations that can valid for more than one edge, I can’t eliminate any assumptions I’ve made. I was hoping you’d provide some clarity. Thanks.

Figure 16 – Page 13.
Center Trellis
Some of the 0.586 should be a 2, 3.414

Figure 19 – Page 15
I think some of the labels are swapped.

Figure 21 – Page 17
If Figure 19 labels were swapped, same applies.

Page 28
For the final equality of Y.
It should be 2*x^4 [0 1 1]T instead of x^4

I think your tutorials are great. They’ve helped me to understand the concept much more clearer; therefore, improving my ability to explain complex concepts at a more laymen’s level.

I really enjoy your tutorials, the ones that I have read have been extremely useful and a great compliment to the courses I’ve taken. Thanks. I probably wouldn’t have sent you this e-mail if it wasn’t for your Amazon comment under Richard Lyons Understanding Digital Signal Processing. I’m reading his book now, I’m glad you decided to spread your knowledge with the same writing style.

Going through your tutorial, I think I may have found some errors in your Figures. There may be an offset in the indexes that generated the calculations. My hand calculations don’t match your Figures, and the numbers used in the examples give calculations that can valid for more than one edge, I can’t eliminate any assumptions I’ve made. I was hoping you’d provide some clarity. Thanks.

Figure 16 – Page 13.

Center Trellis

Some of the 0.586 should be a 2, 3.414

Figure 19 – Page 15

I think some of the labels are swapped.

Figure 21 – Page 17

If Figure 19 labels were swapped, same applies.

Page 28

For the final equality of Y.

It should be 2*x^4 [0 1 1]T instead of x^4

I think your tutorials are great. They’ve helped me to understand the concept much more clearer; therefore, improving my ability to explain complex concepts at a more laymen’s level.