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(To be removed) Offset quadrature phase shift keying modulation

oqpskmod is not recommeded. Use comm.OQPSKModulator instead.


y = oqpskmod(x)
y = oqpskmod(x,ini_phase)



y = oqpskmod(x) modulates the input signal, x, using offset quadrature phase shift keying (OQPSK). The function upsamples by a factor of 2, because OQPSK does not permit an odd number of samples per symbol.

y = oqpskmod(x,ini_phase) specifies the initial phase of the modulated signal.


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Generate random 4-ary data. Create modulator and demodulator objects.

dataIn = randi([0 3],100,1);
oqpskmod = comm.OQPSKModulator;
oqpskdemod = comm.OQPSKDemodulator;

OQPSK modulate the data, and pass it through an AWGN channel.

txSig = oqpskmod(dataIn);
rxSig = awgn(txSig,10);

OQPSK demodulate the received signal. Determine the number of symbol errors.

dataOut = oqpskdemod(rxSig);
numErrs = symerr(dataIn,dataOut)
numErrs = 79

Input Arguments

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Input signal, specified as a vector or matrix of positive integers. The elements of x must have values in the range of [0, 3].

Data Types: double | single

Initial phase of the OQPSK modulation, specified in radians as a real scalar.

Example: pi/4

Data Types: double | single

Output Arguments

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Complex baseband representation of an OQPSK-modulated output signal, returned as a vector or matrix. The columns of y represent independent channels.

Data Types: double | single
Complex Number Support: Yes

Introduced before R2006a

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