sdr.plot.phase_tree(x: NDArray, sps: int, span: int = 4, sample_rate: float | None = None, color: 'index' | str = 'index', **kwargs)

Plots the phase tree of a continuous-phase modulated (CPM) signal signal \(x[n]\).

Parameters:
x: NDArray

The baseband CPM signal \(x[n]\).

sps: int

The number of samples per symbol.

span: int = 4

The number of symbols per raster.

sample_rate: float | None = None

The sample rate \(f_s\) of the signal in samples/s. If None, the x-axis will be labeled as “Samples”.

color: 'index' | str = 'index'

Indicates how to color the rasters. If "index", the rasters are colored based on their index. If a valid Matplotlib color, the rasters are all colored with that color.

**kwargs

Additional keyword arguments to pass to sdr.plot.raster().

Example

Modulate 100 MSK symbols.

In [1]: msk = sdr.MSK(); \
   ...: s = np.random.randint(0, msk.order, 100); \
   ...: x = msk.modulate(s)
   ...: 

In [2]: plt.figure(figsize=(8, 4)); \
   ...: sdr.plot.phase_tree(x, msk.sps)
   ...:
../../_images/sdr_plot_phase_tree_1.png