nitrojacob L1 Preamble Detection & Cross-Correlation Skill 🛰️
Use this skill when continuous or burst RF IQ datasets contain preamble synchronization headers (Barker codes, Zadoff-Chu sequence, Schmidl-Cox OFDM preambles, Bluetooth LE 0xAA/0x55, AIS 0x555555, GSM training sequences). It cross-correlates the stream against known reference waveforms, pinpoints exact packet start indices, and extracts packet segments prior to demodulation and framing identification.
Instructions
- Execute Preamble Detection CLI Tool:
PYTHONPATH=/usr/lib/python3/dist-packages:. .agents/skills/preamble-detection/scripts/detect_preamble.py --input /tmp/rx_stream.sigmf-data --type BT_LE --output /tmp/detected_packet.sigmf-data - Programmatic Usage:
from gr_playground.dsp.packet_detection import L1PacketDetector # Barker Code Cross-Correlation det_res = L1PacketDetector.detect_barker_preamble(iq_samples, barker_length=11, threshold=0.5) print("Packets found:", det_res["num_packets_found"]) print("Start indices:", det_res["peak_indices"]) # Bluetooth LE / GMSK Preamble Detector gmsk_res = L1PacketDetector.detect_gmsk_preamble(iq_samples, preamble_type="BT_LE", threshold=0.5) print("BT_LE packets found:", gmsk_res["num_packets_found"])