QT GUI Frequency Sink

A graphical sink to display multiple signals in frequency.

This is a QT-based graphical sink that takes a set of floating point streams and plots the PSD. Each signal is plotted with a different color, and functions can be used to change the label and color for a given input number.

The sink supports plotting streaming float data or messages. The message port is named "in". The two modes cannot be used simultaneously, and should be set to 0 when using the message mode. GRC handles this issue by providing the "Float Message" type that removes the streaming port(s).

Parameters

(R): Run-time adjustable

Type

options: [Complex, Float, Complex Message, Float Message]

Name

title for the plot

FFT Size

size of the FFT to compute and display. If using the PDU message port to plot samples, the length of each PDU must be a multiple of the FFT size.

options: [32,64,128,256,512,1024,2048,4096,8192,16384,32768]

default: 1024

Spectrum Width

options (if Float input): [Full, Half]

Window Type

options: [Blackman-harris, Hamming, Hann, Blackman, Rectangular, Kaiser, Flat-top]

default: window.WIN_BLACKMAN_hARRIS

Normalize Window Power

options: [Yes, No]

Center Frequency (Hz) (R)

center frequency of signal (only used for x-axis labels)

Bandwidth (Hz)

bandwidth of signal (used to set x-axis labels)

default: samp_rate

Grid

options: [Yes, No]

Autoscale

options: [Yes, No]

Average

options: [None, Low, Medium, High]

Y min

default: -140

Y max

default: 10

Y label

default: "Relative Gain"

Y units

default: "dB"

Number of Inputs

default: 1

Update Period (R)

default: 0.10

Show Msg Ports

options: [Yes, No]

GUI Hint

See GUI Hint

Messages

Inputs

'freq'

set the center frequency

'bw'

set the bandwidth

Outputs

'freq'

the frequency where the output plot was double-clicked

Example Flowgraph

Source Files

C++ files

for Complex input

for Float input

Header files

for Complex input

for Float input

Public header files

TODO

Block definition

gr-qtgui/grc/qtgui_freq_sink_x.block.yml