gr-inspector Signal Detector

Detects a narrowband tone in complex Gaussian noise with gr-inspector. Signal Detector calculates one 1024-bin periodogram at a time; Inspector GUI Sink plots it, overlays the detected RF map, and forwards that map to Message Debug. Enable Manual selection in the plot to drag a band instead.

Author GNU Radio World
Category gr-inspector
Blocks 10
Connections 7
File gr-inspector/signal_detector.grc

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Blocks used

Block	Module	Used
Variable	`GNU Radio`	2
Add	`GNU Radio`	1
GUI Layout	`GNU Radio`	1
Message Debug	`GNU Radio`	1
Noise Source	`GNU Radio`	1
QT GUI Inspector Sink	`gr-inspector`	1
Signal Detector	`gr-inspector`	1
Signal Source	`GNU Radio`	1
Throttle	`GNU Radio`	1

Flowgraph source

gr-inspector/signal_detector.grc

options:
    parameters:
        author: GNU Radio World
        comment: ''
        copyright: ''
        description: Detects a narrowband tone in complex Gaussian noise with gr-inspector. Signal Detector calculates one 1024-bin periodogram at a time; Inspector GUI Sink plots it, overlays the detected RF map, and forwards that map to Message Debug. Enable Manual selection in the plot to drag a band instead.
        generate_options: qt_gui
        id: gr_inspector_Signal_Detector
        title: gr-inspector Signal Detector
    states:
        coordinate: [10, 10]
        rotation: 0
        state: enabled
blocks:
-   name: fft_len
    id: variable
    parameters:
        comment: Periodogram size and detector decimation
        value: '1024'
    states:
        coordinate: [590, 10]
        rotation: 0
        state: enabled
-   name: samp_rate
    id: variable
    parameters:
        comment: Complex baseband sample rate
        value: '48000'
    states:
        coordinate: [760, 10]
        rotation: 0
        state: enabled
-   name: add
    id: blocks_add_xx
    parameters:
        affinity: ''
        alias: ''
        comment: ''
        maxoutbuf: '0'
        minoutbuf: '0'
        num_inputs: '2'
        type: complex
        vlen: '1'
    states:
        coordinate: [370, 200]
        rotation: 0
        state: enabled
-   name: detector
    id: inspector_signal_detector_cvf
    parameters:
        affinity: ''
        alias: ''
        auto: 'False'
        avg: '0.8'
        comment: Mark periodogram bins above the fixed -30 dB threshold
        fft_len: fft_len
        logfile: ''
        maxoutbuf: '0'
        min_bw: '0'
        minoutbuf: '0'
        quant: '0.001'
        samp_rate: samp_rate
        sensitivity: '0.2'
        threshold: '-30'
        window: window.WIN_HAMMING
    states:
        coordinate: [940, 150]
        rotation: 0
        state: enabled
-   name: inspector_gui
    id: inspector_qtgui_sink_vf
    parameters:
        affinity: ''
        alias: ''
        cfreq: '0'
        comment: Plot the PSD and detected bands; Ctrl+drag zooms, right-click zooms out
        fft_len: fft_len
        gui_hint: ''
        manual: 'False'
        maxoutbuf: '0'
        minoutbuf: '0'
        msgports: '1'
        rf_unit: '1'
        samp_rate: samp_rate
    states:
        coordinate: [1380, 170]
        rotation: 0
        state: enabled
-   name: noise
    id: analog_noise_source_x
    parameters:
        affinity: ''
        alias: ''
        amp: '0.03'
        comment: Low background noise makes the occupied band easy to see
        maxoutbuf: '0'
        minoutbuf: '0'
        noise_type: analog.GR_GAUSSIAN
        seed: '0'
        type: complex
    states:
        coordinate: [10, 340]
        rotation: 0
        state: enabled
-   name: rf_map
    id: blocks_message_debug
    parameters:
        affinity: ''
        alias: ''
        comment: Print RF-map changes as center-frequency and bandwidth pairs
        en_uvec: 'True'
        log_level: info
    states:
        coordinate: [130, 480]
        rotation: 0
        state: enabled
-   name: throttle
    id: blocks_throttle2
    parameters:
        affinity: ''
        alias: ''
        comment: Pace the synthetic stream for the live display
        ignoretag: 'True'
        limit: time
        maximum: '0.1'
        maxoutbuf: '0'
        minoutbuf: '0'
        samples_per_second: samp_rate
        type: complex
        vlen: '1'
    states:
        coordinate: [610, 190]
        rotation: 0
        state: enabled
-   name: tone
    id: analog_sig_source_x
    parameters:
        affinity: ''
        alias: ''
        amp: '0.8'
        comment: Signal to locate at +8 kHz
        freq: '8000'
        maxoutbuf: '0'
        minoutbuf: '0'
        offset: '0'
        phase: '0'
        samp_rate: samp_rate
        type: complex
        waveform: analog.GR_COS_WAVE
    states:
        coordinate: [10, 160]
        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: [300, 10]
        rotation: 0
        state: enabled
connections:
- [add, '0', throttle, '0']
- [detector, '0', inspector_gui, '0']
-   src_blk_id: detector
    src_port_id: map_out
    snk_blk_id: inspector_gui
    snk_port_id: map_in
-   src_blk_id: inspector_gui
    src_port_id: map_out
    snk_blk_id: rf_map
    snk_port_id: print
- [noise, '0', add, '1']
- [throttle, '0', detector, '0']
- [tone, '0', add, '0']
metadata:
    file_format: 2
    grc_version: 3.11.0.0