PySDR: Nyquist Sampling and Aliasing
Companion to the Sampling chapter of PySDR
- Author Marc
- Category Analog
- Blocks 8
- Connections 3
- File
analog/sampling_aliasing.grc
Blocks used
| Block | Module | Used |
|---|---|---|
| GUI Layout | GNU Radio | 1 |
| Note | GNU Radio | 1 |
| QT GUI Frequency Sink | GNU Radio | 1 |
| QT GUI Range | GNU Radio | 1 |
| QT GUI Time Sink | GNU Radio | 1 |
| Signal Source | GNU Radio | 1 |
| Throttle | GNU Radio | 1 |
| Variable | GNU Radio | 1 |
Notes in this flowgraph
- Fs = 100 kHz, so Nyquist is 50 kHz. Sweep the tone past 50 kHz and watch the peak fold back
Flowgraph source
analog/sampling_aliasing.grc
options:
parameters:
author: Marc
comment: ''
copyright: ''
description: Companion to the Sampling chapter of PySDR
generate_options: qt_gui
id: PySDR__Nyquist_Sampling_and_Aliasing
title: 'PySDR: Nyquist Sampling and Aliasing'
states:
coordinate: [10, 10]
rotation: 0
state: enabled
blocks:
- name: samp_rate
id: variable
parameters:
comment: ''
value: '100000'
states:
coordinate: [320, 10]
rotation: 0
state: enabled
- name: tone_freq
id: variable_qtgui_range
parameters:
comment: ''
label: Tone frequency (Hz)
min_len: '200'
orient: QtCore.Qt.Horizontal
rangeType: float
start: '100'
step: '100'
stop: '100000'
value: '2000'
widget: counter_slider
states:
coordinate: [730, 10]
rotation: 0
state: enabled
- name: freq_sink
id: qtgui_freq_sink_x
parameters:
affinity: ''
alias: ''
alpha1: '1'
alpha10: '1'
alpha2: '1'
alpha3: '1'
alpha4: '1'
alpha5: '1'
alpha6: '1'
alpha7: '1'
alpha8: '1'
alpha9: '1'
autoscale: 'False'
average: '1.0'
axislabels: 'True'
color1: '"blue"'
color10: '"dark blue"'
color2: '"red"'
color3: '"green"'
color4: '"black"'
color5: '"cyan"'
color6: '"magenta"'
color7: '"yellow"'
color8: '"dark red"'
color9: '"dark green"'
comment: ''
ctrlpanel: 'False'
fc: '0'
fftsize: '1024'
freqhalf: 'False'
grid: 'True'
label1: ''
label10: ''''''
label2: ''''''
label3: ''''''
label4: ''''''
label5: ''''''
label6: ''''''
label7: ''''''
label8: ''''''
label9: ''''''
legend: 'True'
marker1: '-1'
marker10: '-1'
marker2: '-1'
marker3: '-1'
marker4: '-1'
marker5: '-1'
marker6: '-1'
marker7: '-1'
marker8: '-1'
marker9: '-1'
maxoutbuf: '0'
minoutbuf: '0'
name: '"Where the tone appears"'
nconnections: '1'
samp_rate: samp_rate
style1: '1'
style10: '1'
style2: '1'
style3: '1'
style4: '1'
style5: '1'
style6: '1'
style7: '1'
style8: '1'
style9: '1'
tr_chan: '0'
tr_level: '0'
tr_mode: qtgui.TRIG_MODE_FREE
tr_tag: '""'
type: float
update_time: '0.1'
width1: '1'
width10: '1'
width2: '1'
width3: '1'
width4: '1'
width5: '1'
width6: '1'
width7: '1'
width8: '1'
width9: '1'
ymax: '10'
ymin: '-100'
states:
coordinate: [620, 210]
rotation: 0
state: enabled
- name: note_nyq
id: note
parameters:
affinity: ''
alias: ''
comment: ''
note: Fs = 100 kHz, so Nyquist is 50 kHz. Sweep the tone past 50 kHz and watch the peak fold back
states:
coordinate: [290, 110]
rotation: 0
state: enabled
- name: throttle
id: blocks_throttle2
parameters:
affinity: ''
alias: ''
comment: ''
ignoretag: 'True'
limit: auto
maximum: '0.1'
maxoutbuf: '0'
minoutbuf: '0'
samples_per_second: samp_rate
type: float
vlen: '1'
states:
coordinate: [290, 230]
rotation: 0
state: enabled
- name: time_sink
id: qtgui_time_sink_x
parameters:
affinity: ''
alias: ''
alpha1: '1'
alpha10: '1'
alpha2: '1'
alpha3: '1'
alpha4: '1'
alpha5: '1'
alpha6: '1'
alpha7: '1'
alpha8: '1'
alpha9: '1'
autoscale: 'False'
axislabels: 'True'
color1: blue
color10: dark blue
color2: red
color3: green
color4: black
color5: cyan
color6: magenta
color7: yellow
color8: dark red
color9: dark green
comment: ''
ctrlpanel: 'False'
grid: 'True'
label1: Signal 1
label10: Signal 10
label2: Signal 2
label3: Signal 3
label4: Signal 4
label5: Signal 5
label6: Signal 6
label7: Signal 7
label8: Signal 8
label9: Signal 9
legend: 'True'
marker1: '0'
marker10: '-1'
marker2: '-1'
marker3: '-1'
marker4: '-1'
marker5: '-1'
marker6: '-1'
marker7: '-1'
marker8: '-1'
marker9: '-1'
name: '"Samples in the time domain"'
nconnections: '1'
samp_rate: samp_rate
size: '200'
stemplot: 'False'
style1: '1'
style10: '1'
style2: '1'
style3: '1'
style4: '1'
style5: '1'
style6: '1'
style7: '1'
style8: '1'
style9: '1'
tr_chan: '0'
tr_delay: '0'
tr_level: '0'
tr_mode: qtgui.TRIG_MODE_FREE
tr_slope: qtgui.TRIG_SLOPE_POS
tr_tag: '""'
type: float
update_time: '0.1'
width1: '1'
width10: '1'
width2: '1'
width3: '1'
width4: '1'
width5: '1'
width6: '1'
width7: '1'
width8: '1'
width9: '1'
ylabel: Amplitude
ymax: '1.5'
ymin: '-1.5'
yunit: '""'
states:
coordinate: [620, 390]
rotation: 0
state: enabled
- name: tone
id: analog_sig_source_x
parameters:
affinity: ''
alias: ''
amplitude: '1'
comment: ''
frequency: tone_freq
maxoutbuf: '0'
minoutbuf: '0'
samp_rate: samp_rate
type: float
waveform: analog.GR_COS_WAVE
states:
coordinate: [10, 230]
rotation: 0
state: enabled
- name: wasm_gui_layout_0
id: wasm_gui_layout
parameters:
affinity: ''
alias: ''
columns: '12'
comment: ''
layout: '{}'
row_height: '60'
states:
coordinate: [930, 220]
rotation: 0
state: enabled
connections:
- [throttle, '0', freq_sink, '0']
- [throttle, '0', time_sink, '0']
- [tone, '0', throttle, '0']
metadata:
file_format: 1
grc_version: 3.11.0.0