scripts init

scripts/commpy/impairments.py

@@ -0,0 +1,43 @@
+
+# Authors: Veeresh Taranalli <veeresht@gmail.com>
+# License: BSD 3-Clause
+
+"""
+============================================
+Impairments (:mod:`commpy.impairments`)
+============================================
+
+.. autosummary::
+   :toctree: generated/
+
+   add_frequency_offset     -- Add frequency offset impairment.
+
+"""
+
+from numpy import exp, pi, arange
+
+__all__ = ['add_frequency_offset']
+
+def add_frequency_offset(waveform, Fs, delta_f):
+    """
+    Add frequency offset impairment to input signal.
+
+    Parameters
+    ----------
+    waveform : 1D ndarray of floats
+        Input signal.
+
+    Fs : float
+        Sampling frequency (in Hz).
+
+    delta_f : float
+        Frequency offset (in Hz).
+
+    Returns
+    -------
+    output_waveform : 1D ndarray of floats
+        Output signal with frequency offset.
+    """
+
+    output_waveform = waveform*exp(1j*2*pi*(delta_f/Fs)*arange(len(waveform)))
+    return output_waveform