Technical Documentation

🏗️ System Architecture

Overall Architecture

┌─────────────────────────────────────────────────────────────────────────┐
│                         MRRC System Architecture V4.9.3                 │
├─────────────────────────────────────────────────────────────────────────┤
│  Client Layer                                                            │
│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐  ┌──────────┐  │
│  │ Mobile UI    │  │ Desktop UI   │  │ CW Decode    │  │ FT8 Ctrl │  │
│  │ mobile_modern │  │ modern.html  │  │ cw_live.html │  │ ft8_ultron│  │
│  └──────┬───────┘  └──────┬───────┘  └──────┬───────┘  └────┬─────┘  │
│         │                  │                 │                │        │
│         └──────────────────┴─────────────────┴────────────────┘        │
│                                    │                                     │
│                            HTTPS / WebSocket                             │
│                                    ▼                                     │
├─────────────────────────────────────────────────────────────────────────┤
│  Service Layer                                                           │
│  ┌──────────────────────────────────────────────────────────────┐      │
│  │                      MRRC Main (Tornado)                       │      │
│  ├──────────────────────────────────────────────────────────────┤      │
│  │  /WSCTRX     - Main control + audio (PTT/frequency/mode)     │      │
│  │  /WSATR1000  - Tuner power/SWR real-time display             │      │
│  │  /WSCW       - CW backend decode (optional)                  │      │
│  └──────┬─────────────────────────────────────────────┬──────────┘      │
│         │                                             │                  │
│         ▼                                             ▼                  │
│  ┌─────────────────┐                         ┌──────────────────┐     │
│  │  rigctld        │                         │  ATR-1000 Proxy  │     │
│  │  (Hamlib)       │                         │  atr1000_proxy   │     │
│  └────────┬────────┘                         └────────┬─────────┘     │
│           │                                            │                │
│           ▼                                            ▼                │
│  ┌─────────────────┐                         ┌──────────────────┐     │
│  │  Transceiver    │                         │  ATR-1000 Tuner  │     │
│  │  IC-M710       │                         │  Power/SWR Meter │     │
│  └─────────────────┘                         └──────────────────┘     │
│                                                                          │
│  ┌──────────────────────────────────────────────────────────────┐      │
│  │                    FT8/ULTRON Integration (Optional)          │      │
│  ├──────────────────────────────────────────────────────────────┤      │
│  │  ULTRON Automation Tool → JTDX/WSJT-X → UDP 2237             │      │
│  │  DXCC Target Tracking, Smart QSO, Auto CQ                    │      │
│  └──────────────────────────────────────────────────────────────┘      │
└─────────────────────────────────────────────────────────────────────────┘

Core Components

Component	File	Function
Main Program	`MRRC`	WebSocket server, handles audio streams and control commands
Audio Interface	`audio_interface.py`	PyAudio wrapper, supports multiple format decoding
DSP Processing	`wdsp_wrapper.py`	WDSP library wrapper, NR2/AGC/ANF
Transceiver Control	`hamlib_wrapper.py`	rigctld communication wrapper
Tuner Proxy	`atr1000_proxy.py`	ATR-1000 independent proxy process
Voice Assistant	`voice_assistant_service.py`	Whisper ASR + Qwen3-TTS
FT8 Integration	`ft8/ultron.py`	ULTRON automation tool, DXCC tracking

🔊 Audio Processing Pipeline

Receive Audio Chain (RX)

Transceiver Audio (48kHz Float32)
    │
    ▼
┌─────────────────┐
│ DC Removal +    │  Protect downstream processing
│ Soft Clipping   │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ Int16 Convert   │  48kHz → 16bit
└────────┬────────┘
         │
         ▼  (Optional)
┌─────────────────┐
│ WDSP Processing │  NR2/NB/ANF/AGC
│  - Spectral NR  │  15-20dB reduction
│  - Noise Blank  │
│  - Auto Notch   │
│  - AGC Gain     │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ Opus Encode     │  16kHz/20kbps
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ WebSocket       │  Browser transport
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ AudioWorklet    │  Low latency playback
└─────────────────┘

Transmit Audio Chain (TX)

Microphone Input (48kHz)
    │
    ▼
┌─────────────────┐
│ Anti-Alias      │  6kHz lowpass
│ Filter          │
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ Downsample      │  48kHz → 16kHz
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ TX Equalizer    │  3-band EQ presets
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ Opus Decode     │  16kHz → 48kHz
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ WebSocket       │  Send to server
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│ Transceiver In  │  CAT PTT control
└─────────────────┘

🎛️ WDSP Digital Signal Processing

WDSP (Warren Pratt's Digital Signal Processing) is a high-performance DSP library from the OpenHPSDR project, widely used in professional amateur radio software.

Feature Modules

Module	Function	Effect
NR2	Spectral Noise Reduction	15-20dB noise reduction depth
NB	Noise Blanker	Eliminates impulse interference
ANF	Automatic Notch Filter	Removes single-tone interference
AGC	Automatic Gain Control	4 selectable modes

AGC Modes

LONG: Long delay, suitable for stable signals
SLOW: Slow response, balanced choice
MED: Medium response, default recommendation
FAST: Fast response, suitable for rapid QSY

📡 CW Decoding System Architecture

MRRC V4.9 introduces a complete CW real-time decoding system with a Browser-First AI design philosophy.

Dual-Mode Decoding Architecture

┌─────────────────────────────────────────────────────────────┐
│                     CW Decoding Dual-Mode                   │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  Frontend Mode (Recommended)                                 │
│  ┌──────────────┐    ┌──────────────┐    ┌──────────────┐  │
│  │ Audio Stream │───►│ ONNX Runtime │───►│ CTC Decode   │  │
│  │ (16kHz)      │    │ (2MB model)  │    │              │  │
│  └──────────────┘    └──────────────┘    └──────────────┘  │
│         │                                       │             │
│         │                              ┌────────▼────────┐    │
│         │                              │ QSO State       │    │
│         │                              │ Machine         │    │
│         │                              │ Smart Reply     │    │
│         │                              └────────────────┘    │
│         │                                                     │
│  Latency: <50ms                                              │
│  Dependencies: None (pure browser)                           │
│                                                              │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  Backend Mode (Alternative)                                  │
│  ┌──────────────┐    ┌──────────────┐    ┌──────────────┐  │
│  │ WebSocket   │───►│ morseangel   │───►│ Text Output  │  │
│  │ /WSCW       │    │ (PyTorch)    │    │              │  │
│  └──────────────┘    └──────────────┘    └──────────────┘  │
│                                                              │
│  Latency: <100ms                                            │
│  Dependencies: PyTorch + CUDA                                │
│                                                              │
└─────────────────────────────────────────────────────────────┘

Technical Specifications

Metric	Frontend Mode	Backend Mode
Model Size	2MB (ONNX)	160MB (PyTorch)
Inference Latency	<50ms	<100ms
Character Error Rate	<3%	<2%
Network Dependency	None	Required

Try It Live

CW Real-time Decode CW Test Page

📊 ATR-1000 Integration

System Architecture

┌─────────────────────────────────────────────────────────────┐
│                    ATR-1000 Integration                      │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  Frontend (mobile_modern.js)                                 │
│      │                                                        │
│      │ WebSocket /WSATR1000                                  │
│      ▼                                                        │
│  ┌─────────────────┐                                         │
│  │ MRRC Main       │  Message routing + batch broadcast     │
│  └────────┬────────┘                                         │
│           │                                                  │
│           │ Unix Socket                                      │
│           ▼                                                  │
│  ┌─────────────────┐     WebSocket                          │
│  │ atr1000_proxy  │◄────────────────────────────────┐        │
│  │ Independent    │                                  │        │
│  │ Process        │                                  │        │
│  └────────┬────────┘                                  │        │
│           │                                             │        │
│           └──────────────────────┬──────────────────────┘        │
│                                  │                                │
│                                  ▼                                │
│                    ┌──────────────────────┐                      │
│                    │  ATR-1000 Device     │                      │
│                    │  192.168.1.63:60001  │                      │
│                    │  Power/SWR/Relay     │                      │
│                    └──────────────────────┘                      │
└─────────────────────────────────────────────────────────────┘

Smart ATU Learning

Auto Learning: Records frequency-to-tuner parameter mapping during each transmission
Quick Tune: Automatically applies learned parameters when frequency changes
Persistence: Saves to atr1000_tuner.json

📻 FT8/ULTRON Integration

ULTRON Enhanced is MRRC V4.9's new FT8 digital mode automation tool, supporting JTDX, WSJT-X, MSHV software integration.

Core Features

Feature	Description
Auto CQ	Automatically call CQ when idle
Smart Response	Automatically respond to incoming calls
DXCC Tracking	Entity whitelist, intelligent selection
Band Strategy	Different targets per band
Log Analysis	Automatically analyze worked entities

Run Commands

# Enter FT8 directory
cd ft8

# Run ULTRON (Python version)
python run_ultron.py

# DXCC enhanced mode
python ultron_dxcc.py

# Analyze DXCC status
python dxcc_analyzer.py

Try It Live

FT8 Console

📝 Communication Protocols

WebSocket Commands

Command	Format	Description
Set Frequency	`setFreq:14074000`	In Hz
Set Mode	`setMode:USB`	USB/LSB/CW/FM
PTT Control	`setPTT:1`	1=TX, 0=RX
Volume	`setRXA:50`	0-100
Filter	`setFilter:2400`	In Hz
WDSP Control	`setWDSP:NR2:1`	Module:on/off

🏗️ System Architecture

Overall Architecture

Core Components

🔊 Audio Processing Pipeline

Receive Audio Chain (RX)

Transmit Audio Chain (TX)

🎛️ WDSP Digital Signal Processing

Feature Modules

AGC Modes

📡 CW Decoding System Architecture

Dual-Mode Decoding Architecture

Technical Specifications

Try It Live

📊 ATR-1000 Integration

System Architecture

Smart ATU Learning

📻 FT8/ULTRON Integration

Core Features

Run Commands

Try It Live

📝 Communication Protocols

WebSocket Commands

📚 Reference Documentation

Project Documentation

External Resources

Need More Help?