Re: A question on pseudo-random codes

On Aug 18, 8:33 pm, "nagarajcs" <nagara...@xxxxxxxx> wrote:
On Aug 17, 10:46 am, "nagarajcs" <nagara...@xxxxxxxx> wrote:
Hi all,

For m-sequences(generated by an n-bit LFSR with predefined feedback
taps),
the next generated bit can be determined by the current state of the
shift
register. In other words, given the whole sequence, the shift of any
bit
can be uniquely identified by looking at n-bits (preceding or
succeeding
that bit).

For Gold codes, the same is possible with 2n-bits.

I want to know what is the term used in literature for this length
which
can identify the shift in a random sequence.

Sorry if this question is a very basic one.

Nagaraj

I think you're referring to "linear span". Googled and found these
course notes; check out the definition at the top of page 2:

http://comsec.uwaterloo.ca/~ggong/EE599S07/BM-chapter99.pdf

- Kenn

Thanks mate!! Yes.. it is the "Linear Span".

Does the word 'linear' relate to the linear in LFSR? Is there a generic
term for the sequences generated not necessarily through LFSR?

Nagaraj

Linear... sounds reasonable. PRBS (pseudo random bit sequences)
generally describes sequences generated through either an LFSR or
other deterministic process. Although an LFSR isn't necessarily
constrained to be binary (it could be over any finite field), so the
"B" in PRBS doesn't quite fit.

- Kenn
.

Relevant Pages

  • Re: 8 Bit Random Numbers
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