qpsk-mod 0.1.0

A library for QPSK modulation

qpsk_mod

Perform Quadrature Phase Shift Keying (QPSK) modulation on the input signal.

Parameters:
a (array-like): Input binary data stream.
fc (float): Carrier frequency.
of (int): Oversampling factor, determining the number of samples per symbol.

Returns:
tuple:
    s_t (numpy.ndarray): The modulated signal in the time domain.
    I (numpy.ndarray): The in-phase component of the input signal.
    Q (numpy.ndarray): The quadrature component of the input signal.

This function performs the following steps:
1. Separates the input data stream into in-phase (I) and quadrature (Q) components.
2. Upsamples and converts the binary data into bipolar format.
3. Modulates the in-phase component with a cosine carrier.
4. Modulates the quadrature component with a sine carrier.
5. Combines the modulated components to form the QPSK modulated signal.
6. Plots various intermediate signals for visualization.

Example:
>>>import qpsk_mod as qp
>>> a = np.array([0, 1, 1, 0, 1, 1, 0, 0])
>>> fc = 100
>>> of = 4
>>> s_t, I, Q = qp.qpsk_mod(a, fc, of)

Installation

pip install qpsk-mod