Convert mask vector to shift for shift register configuration
shift = mask2shift(prpoly,mask)
shift = mask2shift(prpoly,mask) returns
the shift that is equivalent to a mask, for a linear feedback shift
register whose connections are specified by the primitive polynomial prpoly.
The prpoly input can have one of these formats:
A binary vector that lists the coefficients of the primitive polynomial in order of descending powers
An integer scalar whose binary representation gives the coefficients of the primitive polynomial, where the least significant bit is the constant term
The mask input is a binary vector whose length
is the degree of the primitive polynomial.
To save time, mask2shift does not check that prpoly is
primitive. If it is not primitive, the output is not meaningful. To
find primitive polynomials, use primpoly or
see [2].
For more information about how masks and shifts are related
to pseudonoise sequence generators, see shift2mask.
If A is a root of the primitive polynomial and m(A) is the mask
polynomial evaluated at A, the equivalent shift s solves the equation
As = m(A). To interpret the vector mask as
a polynomial, treat mask as a list of coefficients
in order of descending powers.
[1] Lee, J. S., and L. E. Miller, CDMA Systems Engineering Handbook, Boston, Artech House, 1998.
[2] Simon, Marvin K., Jim K. Omura, et al., Spread Spectrum Communications Handbook, New York, McGraw-Hill, 1994.
isprimitive | log | primpoly | shift2mask