Generator of ensemble maximal length sequences

Thread Starter

FabulouSS

Joined Feb 5, 2019
10
Hello!

I can't understand how the M-sequence generator is physically implemented.
Specifically, I am interested in how to "shove" the value of a1 / a2 / a3 into the register
(see picture).
In Micro-Cap, I could not simulate work. :(
I would be grateful for the help! :)

I am writing with Google translator!


Я не могу понять, как физически реализуется генератор M-последовательности. Конкретно меня интересует то, как "засунуть" в регистр значение a1/a2/a3 (см. картинку). В Micro-Cap/Simulink у меня не вышло смоделировать работу. :(
Буду благодарен за помощь!
 

DickCappels

Joined Aug 21, 2008
6,098
Have you considered using a digital multiplexer followed by a transparent D latch in the data path for those three values?

When it is time to load the initial condition, set the multiplexers to select the preset inputs and clock the data into the D latches. Change the multiplexers to select the feedback taps and after the first clock to the generator but before the second set the clock input to the D latches so it can pass the data and then you can happily generate your sequence.

Since the pattern will repeat, do you really need to preload the generator?
 

Thread Starter

FabulouSS

Joined Feb 5, 2019
10
Have you considered using a digital multiplexer followed by a transparent D latch in the data path for those three values?
Multiplexer? So is it possible? Can an example with a multiplexer, if not difficult?

I figured out the generation! I attach pictures of the generator and the results of its work, as well as the generator itself in the Microcap program.


Unfortunately, I could not cope with one ambiguity - what is the volume of the M-sequence ensemble? I ran across the following formula:


Then for my case (three-digit register) the ensemble volume is equal to two. And I was able to build as many as four signals that are trans-orthogonal.

File in microcap:
View attachment MLS.rar

Thank you for attention! :)
 

Thread Starter

FabulouSS

Joined Feb 5, 2019
10
It seems I figured out the numbering and ensemble!
Numbered by the first three (since m = 3) bits:

000 - #0
001 - #1
010 - #2
011 - #3
100 - #4
101 - #5
110 - #6
111 - #7

Micro-Cap:
View attachment M-sequence.rar

Thank you all, now I figured it out! :)
 
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