CaribouLite SDR Complete #
Hardware adoption of the CaribouLite SDR HAT — a software-defined radio receiver on a Raspberry Pi,
built as a baked image in deevnet-image-factory, proven on the
Pi Lab
bank, and graduated to dedicated hardware.
The project write-up is at Pi SDR.
Purpose #
Software-defined radio (SDR) receiver for RF signal monitoring and experimentation. The CaribouLite HAT provides dual-channel SDR capability directly on the Pi’s GPIO header.
Hardware #
| Component | Specification |
|---|---|
| Compute | Raspberry Pi 4 Model B, 8GB |
| SDR HAT | CaribouLite SDR |
| Storage | 32GB SD card (minimum) |
| Antenna | SMA connector, antenna per use case |
CaribouLite Specifications #
| Attribute | Value |
|---|---|
| Frequency range | 30 MHz – 6 GHz (with gaps) |
| Channels | 2 (S1000: sub-1GHz, HiF: 30MHz-6GHz) |
| ADC | 13-bit |
| Bandwidth | Up to 2.5 MHz per channel |
| Interface | GPIO header (directly mounted) |
Network Position #
graph LR
A[Core Router] <--> B[Access Switch
IoT VLAN] <--> C[CaribouLite SDR
Pi4 + SDR HAT]
Deployed on the IoT VLAN for isolation from management traffic.
Software Stack #
| Layer | Component |
|---|---|
| OS | Raspberry Pi OS (64-bit) |
| SDR Driver | CaribouLite kernel module |
| SDR Framework | SoapySDR |
| Applications | GNU Radio, SDR++ (optional GUI) |
Configuration #
Kernel Module #
The CaribouLite kernel module loads automatically via udev rules. Verify with:
lsmod | grep cariboulite
SoapySDR Integration #
CaribouLite integrates with SoapySDR for application compatibility:
SoapySDRUtil --find
SoapySDRUtil --probe="driver=Cariboulite"
Test Scripts #
Located at /opt/deevnet/tests/:
| Script | Purpose |
|---|---|
test-sdr-detect.sh | Verify CaribouLite HAT detected |
test-sdr-channels.sh | Confirm both SDR channels operational |
test-sdr-receive.sh | Capture samples, verify data flow |
Running Tests #
sudo /opt/deevnet/tests/run-all-tests.sh
Expected output:
[PASS] Network connectivity
[PASS] CaribouLite HAT detected
[PASS] Kernel module loaded
[PASS] SoapySDR integration
[PASS] Channel S1000 operational
[PASS] Channel HiF operational
Post-Startup Scripts #
Located at /opt/deevnet/post-startup/:
| Script | Purpose |
|---|---|
init-sdr.sh | Initialize SDR hardware, set default gains |
These run on first boot after the hardware is detected.
Use Cases #
| Application | Description |
|---|---|
| ADS-B reception | Aircraft tracking (1090 MHz) |
| FM broadcast | Local FM station monitoring |
| Weather satellite | NOAA APT reception (137 MHz) |
| ISM band monitoring | 433/868/915 MHz IoT traffic |
| Amateur radio | HF/VHF/UHF experimentation |
Maintenance #
| Task | Frequency | Procedure |
|---|---|---|
| Firmware updates | As released | Check CaribouLite GitHub for updates |
| Test validation | Monthly | Run test scripts, verify all pass |
| Antenna inspection | Quarterly | Check connections, replace worn cables |
Project History #
The project was tracked on the Roadmap until it completed; its plan is kept here.
Vision & Scope #
Adopt the CaribouLite SDR HAT and deploy a software-defined radio platform on Raspberry Pi for RF signal monitoring and experimentation.
In scope: CaribouLite hardware integration; remote SDR access via network streaming; client
software for tuning and visualization; a baked image via deevnet-image-factory.
Out of scope: transmit capability; signal decoding and demodulation pipelines.
Milestones #
| Milestone | Tasks | Status |
|---|---|---|
| Requirements | supported frequency ranges defined; network streaming protocol defined | ✅ |
| CaribouLite backend | base Pi image with Ansible support; CaribouLite driver installation; post-image configuration | ✅ |
| SDR client | network streaming configuration; GQRX (or alternative) front-end setup | ✅ |
| Documentation | build documentation; client documentation | ✅ |