Documentation

This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English verison of the page.

Note: This page has been translated by MathWorks. Please click here
To view all translated materals including this page, select Japan from the country navigator on the bottom of this page.

mskmod

Minimum shift keying modulation

Syntax

y = mskmod(x,nsamp)
y = mskmod(x,nsamp,dataenc)
y = mskmod(x,nsamp,dataenc,ini_phase)
[y,phaseout] = mskmod(...)

Description

y = mskmod(x,nsamp) outputs the complex envelope y of the modulation of the message signal x using differentially encoded minimum shift keying (MSK) modulation. The elements of x must be 0 or 1. nsamp denotes the number of samples per symbol in y and must be a positive integer. The initial phase of the MSK modulator is 0. If x is a matrix with multiple rows and columns, the function treats the columns as independent channels and processes them independently.

y = mskmod(x,nsamp,dataenc) specifies the method of encoding data for MSK. dataenc can be either 'diff' for differentially encoded MSK or 'nondiff' for nondifferentially encoded MSK.

y = mskmod(x,nsamp,dataenc,ini_phase) specifies the initial phase of the MSK modulator. ini_phase is a row vector whose length is the number of channels in y and whose values are integer multiples of pi/2. To avoid overriding the default value of dataenc, set dataenc to [].

[y,phaseout] = mskmod(...) returns the final phase of y. This is useful for maintaining phase continuity when you are modulating a future bit stream with differentially encoded MSK. phaseout has the same dimensions as the ini_phase input, and assumes the values 0, pi/2, pi, and 3*pi/2.

Examples

collapse all

Generate a random binary signal.

x = randi([0 1],100,1);

MSK modulate the data.

y = mskmod(x,8,[],pi/2);

Pass the signal through an AWGN channel. Display the eye diagram.

z = awgn(y,30,'measured');
eyediagram(z,16);

References

[1] Pasupathy, Subbarayan, “Minimum Shift Keying: A Spectrally Efficient Modulation,” IEEE Communications Magazine, July, 1979, pp. 14–22.

Introduced before R2006a

Was this topic helpful?