BBC Frequency Hop Control

A jam-resistant BBC control channel that commands a frequency hop.
Author James Morrison
Category gr-bbc
Blocks 29
Connections 18
File gr-bbc/bbc_fhss_control.grc
Press Load to open this flowgraph in an editor embedded above, then ▶ to run it. Nothing is downloaded until you do.
Open in the full editor ▶ Download the .grc
Blocks used

Block	Module	Used
Variable	`GNU Radio`	10
OOK Modulator	`gr-bbc`	2
Throttle	`GNU Radio`	2
Vector Source	`GNU Radio`	2
Add	`GNU Radio`	1
BBC Decoder	`gr-bbc`	1
BBC Encoder	`gr-bbc`	1
BBC Frequency Command	`GNU Radio`	1
Frequency Xlating FIR Filter	`GNU Radio`	1
Message Debug	`GNU Radio`	1
Multiply Const	`GNU Radio`	1
Null Sink	`GNU Radio`	1
OOK Demodulator	`gr-bbc`	1
QT GUI Waterfall Sink	`GNU Radio`	1
Signal Source	`GNU Radio`	1
Stream to Vector	`GNU Radio`	1
Vector to Stream	`GNU Radio`	1
Flowgraph source

gr-bbc/bbc_fhss_control.grc
options:
  parameters:
    author: James Morrison
    catch_exceptions: 'True'
    category: '[GRC Hier Blocks]'
    cmake_opt: ''
    comment: ''
    copyright: ''
    description: A jam-resistant BBC control channel that commands a frequency hop.
    gen_cmake: 'On'
    gen_linking: dynamic
    generate_options: qt_gui
    hier_block_src_path: '.:'
    id: bbc_fhss_control
    max_nouts: '0'
    output_language: python
    placement: (0,0)
    qt_qss_theme: ''
    realtime_scheduling: ''
    run: 'True'
    run_command: '{python} -u {filename}'
    run_options: prompt
    sizing_mode: fixed
    thread_safe_setters: ''
    title: BBC Frequency Hop Control
    window_size: ''
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [10, 10]
    rotation: 0
    state: enabled
blocks:
- name: MESSAGE_LENGTH
  id: variable
  parameters:
    comment: ''
    value: '8'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [600, 10]
    rotation: 0
    state: enabled
- name: CODEWORD_LENGTH
  id: variable
  parameters:
    comment: ''
    value: '1024'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [830, 10]
    rotation: 0
    state: enabled
- name: CHECKSUM_BITS
  id: variable
  parameters:
    comment: ''
    value: '32'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1080, 10]
    rotation: 0
    state: enabled
- name: samp_rate
  id: variable
  parameters:
    comment: ''
    value: 128e3
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1300, 10]
    rotation: 0
    state: enabled
- name: symbol_rate
  id: variable
  parameters:
    comment: ''
    value: '8000'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1470, 10]
    rotation: 0
    state: enabled
- name: carrier_freq
  id: variable
  parameters:
    comment: Control channel, as a baseband offset.
    value: 20e3
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [10, 170]
    rotation: 0
    state: enabled
- name: tone_freq
  id: variable
  parameters:
    comment: The payload signal that gets hopped.
    value: 5e3
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [180, 170]
    rotation: 0
    state: enabled
- name: jam_amplitude
  id: variable
  parameters:
    comment: Jammer power relative to the control channel.
    value: '1.0'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [350, 170]
    rotation: 0
    state: enabled
- name: jam_bytes
  id: variable
  parameters:
    comment: ''
    value: '[0x0d, 0xb4, 0x5b, 0x02] * 1024'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [550, 170]
    rotation: 0
    state: enabled
- name: commands
  id: variable
  parameters:
    comment: Two hop commands in hex, matching Message Debug's display; sent in turn.
    value: '[0x2b, 0x32, 0x30, 0x30, 0x30, 0x30, 0x00, 0x00, 0x2d, 0x32, 0x30, 0x30, 0x30, 0x30, 0x00, 0x00]'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [830, 170]
    rotation: 0
    state: enabled
- name: blocks_vector_source_x_0
  id: blocks_vector_source_x
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    repeat: 'True'
    tags: '[]'
    type: byte
    vector: commands
    vlen: MESSAGE_LENGTH
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [10, 270]
    rotation: 0
    state: enabled
- name: bbc_bbc_encoder_0
  id: bbc_bbc_encoder
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    message_length: MESSAGE_LENGTH
    codeword_length: CODEWORD_LENGTH
    checksum_length: CHECKSUM_BITS
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [360, 270]
    rotation: 0
    state: enabled
- name: blocks_vector_to_stream_0
  id: blocks_vector_to_stream
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    num_items: CODEWORD_LENGTH
    type: byte
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [800, 290]
    rotation: 0
    state: enabled
- name: bbc_OOKModulator_0
  id: bbc_OOKModulator
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    carrier_freq: carrier_freq
    samp_rate: samp_rate
    symbol_rate: symbol_rate
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1130, 270]
    rotation: 0
    state: enabled
- name: blocks_vector_source_x_1
  id: blocks_vector_source_x
  parameters:
    affinity: ''
    alias: ''
    comment: Jammer payload
    maxoutbuf: '0'
    minoutbuf: '0'
    repeat: 'True'
    tags: '[]'
    type: byte
    vector: jam_bytes
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [360, 410]
    rotation: 0
    state: enabled
- name: bbc_OOKModulator_1
  id: bbc_OOKModulator
  parameters:
    affinity: ''
    alias: ''
    comment: Jammer on the control channel
    maxoutbuf: '0'
    minoutbuf: '0'
    carrier_freq: carrier_freq
    samp_rate: samp_rate
    symbol_rate: symbol_rate
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [800, 400]
    rotation: 0
    state: enabled
- name: blocks_multiply_const_vxx_0
  id: blocks_multiply_const_vxx
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    const: jam_amplitude
    type: complex
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1130, 420]
    rotation: 0
    state: enabled
- name: blocks_add_xx_0
  id: blocks_add_xx
  parameters:
    affinity: ''
    alias: ''
    comment: Marks are added, never removed.
    maxoutbuf: '0'
    minoutbuf: '0'
    num_inputs: '2'
    type: complex
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1470, 290]
    rotation: 0
    state: enabled
- name: blocks_throttle2_0
  id: blocks_throttle2
  parameters:
    affinity: ''
    alias: ''
    comment: Keeps the waterfall running in real time.
    maxoutbuf: '0'
    minoutbuf: '0'
    ignoretag: 'True'
    limit: auto
    maximum: '0.1'
    samples_per_second: samp_rate
    type: complex
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [80, 560]
    rotation: 0
    state: enabled
- name: bbc_OOKDemodulator_0
  id: bbc_OOKDemodulator
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    bandwidth: '0'
    carrier_freq: carrier_freq
    samp_rate: samp_rate
    symbol_rate: symbol_rate
    threshold: '0.25'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [410, 560]
    rotation: 0
    state: enabled
- name: blocks_stream_to_vector_0
  id: blocks_stream_to_vector
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    num_items: CODEWORD_LENGTH
    type: byte
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [740, 580]
    rotation: 0
    state: enabled
- name: bbc_bbc_decoder_0
  id: bbc_bbc_decoder
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    message_length: MESSAGE_LENGTH
    codeword_length: CODEWORD_LENGTH
    checksum_length: CHECKSUM_BITS
    max_candidates: '256'
    max_steps: '5000000'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1030, 740]
    rotation: 0
    state: enabled
- name: blocks_null_sink_0
  id: blocks_null_sink
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    type: byte
    vlen: MESSAGE_LENGTH
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [130, 1150]
    rotation: 0
    state: enabled
- name: blocks_message_debug_0
  id: blocks_message_debug
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    en_uvec: 'True'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [130, 1250]
    rotation: 0
    state: enabled
- name: wasm_bbc_frequency_command_0
  id: wasm_bbc_frequency_command
  parameters:
    comment: Decoded message to hop command; browser-native replacement for the upstream Embedded Python adapter.
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [130, 1050]
    rotation: 0
    state: enabled
- name: analog_sig_source_x_0
  id: analog_sig_source_x
  parameters:
    affinity: ''
    alias: ''
    comment: The signal being hopped.
    maxoutbuf: '0'
    minoutbuf: '0'
    amp: '1'
    freq: tone_freq
    offset: '0'
    phase: '0'
    samp_rate: samp_rate
    type: complex
    waveform: analog.GR_COS_WAVE
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [1030, 560]
    rotation: 0
    state: enabled
- name: blocks_throttle2_0_0
  id: blocks_throttle2
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    ignoretag: 'True'
    limit: auto
    maximum: '0.1'
    samples_per_second: samp_rate
    type: complex
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [130, 910]
    rotation: 0
    state: enabled
- name: freq_xlating_fir_filter_xxx_0
  id: freq_xlating_fir_filter_xxx
  parameters:
    affinity: ''
    alias: ''
    comment: Hops when the control channel says so.
    maxoutbuf: '0'
    minoutbuf: '0'
    center_freq: '0'
    decim: '1'
    samp_rate: samp_rate
    taps: '1'
    type: ccc
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [520, 920]
    rotation: 0
    state: enabled
- name: qtgui_waterfall_sink_x_0
  id: qtgui_waterfall_sink_x
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    alpha1: '1.0'
    alpha2: '1.0'
    alpha3: '1.0'
    alpha4: '1.0'
    alpha5: '1.0'
    alpha6: '1.0'
    alpha7: '1.0'
    alpha8: '1.0'
    alpha9: '1.0'
    alpha10: '1.0'
    color1: '0'
    color2: '0'
    color3: '0'
    color4: '0'
    color5: '0'
    color6: '0'
    color7: '0'
    color8: '0'
    color9: '0'
    color10: '0'
    label1: ''
    label2: ''
    label3: ''
    label4: ''
    label5: ''
    label6: ''
    label7: ''
    label8: ''
    label9: ''
    label10: ''
    axislabels: 'True'
    bw: samp_rate
    fc: '0'
    fftsize: '1024'
    freqhalf: 'True'
    grid: 'False'
    gui_hint: ''
    int_max: '10'
    int_min: '-140'
    legend: 'True'
    name: '"Hopping signal"'
    nconnections: '1'
    showports: 'False'
    type: complex
    update_time: '0.10'
    wintype: window.WIN_BLACKMAN_hARRIS
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [930, 900]
    rotation: 0
    state: enabled
connections:
- - blocks_vector_source_x_0
  - '0'
  - bbc_bbc_encoder_0
  - '0'
- - bbc_bbc_encoder_0
  - '0'
  - blocks_vector_to_stream_0
  - '0'
- - blocks_vector_to_stream_0
  - '0'
  - bbc_OOKModulator_0
  - '0'
- - bbc_OOKModulator_0
  - '0'
  - blocks_add_xx_0
  - '0'
- - blocks_vector_source_x_1
  - '0'
  - bbc_OOKModulator_1
  - '0'
- - bbc_OOKModulator_1
  - '0'
  - blocks_multiply_const_vxx_0
  - '0'
- - blocks_multiply_const_vxx_0
  - '0'
  - blocks_add_xx_0
  - '1'
- - blocks_add_xx_0
  - '0'
  - blocks_throttle2_0
  - '0'
- - blocks_throttle2_0
  - '0'
  - bbc_OOKDemodulator_0
  - '0'
- - bbc_OOKDemodulator_0
  - '0'
  - blocks_stream_to_vector_0
  - '0'
- - blocks_stream_to_vector_0
  - '0'
  - bbc_bbc_decoder_0
  - '0'
- - bbc_bbc_decoder_0
  - '0'
  - blocks_null_sink_0
  - '0'
- - bbc_bbc_decoder_0
  - decoded
  - blocks_message_debug_0
  - print
- - bbc_bbc_decoder_0
  - decoded
  - wasm_bbc_frequency_command_0
  - decoded
- - wasm_bbc_frequency_command_0
  - freq
  - freq_xlating_fir_filter_xxx_0
  - freq
- - analog_sig_source_x_0
  - '0'
  - blocks_throttle2_0_0
  - '0'
- - blocks_throttle2_0_0
  - '0'
  - freq_xlating_fir_filter_xxx_0
  - '0'
- - freq_xlating_fir_filter_xxx_0
  - '0'
  - qtgui_waterfall_sink_x_0
  - '0'
metadata:
  file_format: 1
  grc_version: 3.10.9.2