APAB — Agentic Phased Array Builder

LLM-driven phased-array antenna design and analysis via MCP tools.

APAB connects an LLM agent to engineering tools for phased-array antenna design: full-wave unit-cell simulation with mutual coupling (over frequency, scan angle, polarization) propagated into array-level patterns and system-level metrics.

Features

• 17 MCP tools — unit-cell simulation (EdgeFEM), array patterns, system-level trades, import/export, plotting
• Agent orchestrator — natural-language design sessions with automatic tool dispatch
• Full pipeline — unit cell → coupling → pattern → system metrics in one run
• Trade studies — DOE sampling with Pareto extraction for multi-objective optimization
• Offline-first — default Ollama provider runs fully local; remote providers opt-in
• Observable — OpenTelemetry traces for every session, turn, LLM call, and tool call; run bundles with audit log, provenance manifest, and trace.jsonl
• Framework-neutral — same MCP tools drive APAB's own agent, a Strands agent, or a deterministic LangGraph pipeline
• Extensible — plugin entry points for LLM providers, EM adapters, and compute backends

Installation

Requires Python 3.10+.

Install from PyPI

pip install apab[ollama]            # array-level tools + Ollama (no C++ deps)
pip install apab[ollama,edgefem]    # + full-wave unit-cell simulation (EdgeFEM)
pip install apab[openai]            # + OpenAI provider
pip install apab[anthropic]         # + Anthropic provider
pip install apab[observability]    # + OpenTelemetry tracing
pip install apab[strands]          # + Strands Agents adapter
pip install apab[langgraph]        # + deterministic LangGraph pipeline

For the default LLM provider, install Ollama and pull a model:

ollama pull qwen2.5-coder:14b

EdgeFEM (optional)

EdgeFEM (full-wave solver) is a C++ extension that requires CMake and Eigen3. Only needed for unit-cell simulation — array pattern and system tools work without it.

• macOS: brew install cmake eigen
• Ubuntu/Debian: sudo apt-get install cmake libeigen3-dev
• Windows: Install CMake from cmake.org, Eigen3 via vcpkg

Then: pip install apab[edgefem]

Development Installation

git clone https://github.com/jman4162/agentic-phased-array-builder.git
cd agentic-phased-array-builder
python3 -m venv .venv
source .venv/bin/activate
pip install -e ".[dev,ollama,edgefem]"

Quick Start — CLI

# 1. Initialize a project with a ready-to-run config
apab init --name my_array --dir ./my_project --quickstart
cd my_project

# 2. Check your environment (Ollama running? Model pulled?)
apab doctor

# 3. Start an interactive design session
apab design
# Try prompts like:
#   "Design an 8x8 patch array at 28 GHz with Taylor tapering"
#   "Compute the array pattern and evaluate system metrics"

# 4. Or run non-interactively from config
apab run

# 5. Autonomous optimization (inspired by autoresearch)
apab optimize --protocol research.md --max-experiments 20
# Agent iterates: propose change → simulate → keep/discard → repeat

# 6. Generate a report from a run
apab report <run_id>

# 7. Run as MCP server (for Claude Desktop, etc.)
apab mcp serve

For full-wave unit-cell simulation (requires EdgeFEM), use --quickstart-fullwave instead of --quickstart.

Quick Start — Python API

from apab import ArraySpec, ScanPoint, PAMPatternEngine

spec = ArraySpec(
    size=[8, 8],
    spacing_m=[0.005, 0.005],
    taper="uniform",
    steer=ScanPoint(theta_deg=15, phi_deg=0),
)
engine = PAMPatternEngine()
result = engine.full_pattern(spec, freq_hz=28e9, theta0=0, phi0=0)
print(f"Directivity: {result.directivity_dbi:.2f} dBi")
print(f"Sidelobe level: {result.sidelobe_level_db:.2f} dB")

This creates an 8x8 element array with half-wavelength spacing at 28 GHz, computes the full 2-D radiation pattern, and returns directivity and sidelobe level. For a complete workflow including unit-cell simulation, mutual coupling, and link budgets, see examples/06_full_pipeline_case_study.py.

See examples/ for more: coupling analysis, trade studies, agent sessions, and Touchstone import.

Case Study

See examples/06_full_pipeline_case_study.py for a complete 28 GHz 5G phased-array case study with EdgeFEM FEM simulation, array patterns, mutual coupling, link budget, and trade study. A companion paper is in examples/case_study_paper.tex.

Configuration

Edit apab.yaml to configure your project:

project:
  name: my_array
  workspace: ./workspace

llm:
  provider: ollama
  model: qwen2.5-coder:14b
  base_url: http://localhost:11434

unit_cell:
  period_x_mm: 5.0
  period_y_mm: 5.0
  substrate_height_mm: 0.254
  substrate_eps_r: 2.2
  patch_length_mm: 3.0
  patch_width_mm: 3.8

sweep:
  freq_start_ghz: 27.0
  freq_stop_ghz: 29.0
  freq_points: 5
  theta_max_deg: 60
  theta_points: 7
  phi_points: 5

array:
  size: [8, 8]
  spacing_m: [0.005, 0.005]
  taper: taylor
  steer:
    theta_deg: 0
    phi_deg: 0

Architecture

┌─────────────────────────────────────────────────┐
│  Agent Orchestrator (LLM ↔ tool-calling loop)   │
├─────────────────────────────────────────────────┤
│  MCP Tool Layer (17 tools via FastMCP)          │
├─────────────────────────────────────────────────┤
│  Domain Wrappers (PAM, PAS, EdgeFEM, importers) │
├─────────────────────────────────────────────────┤
│  External Libraries (edgefem, phased-array-*)   │
└─────────────────────────────────────────────────┘

Available MCP Tools

Observability

Every run_to_completion produces a run bundle: audit.json (tool-call audit log), manifest.json (config hash, dependency versions, status, token usage), and, with tracing enabled, trace.jsonl (one JSON object per OpenTelemetry span). All three share a trace ID.

observability:
  enabled: true
  otlp_endpoint: http://localhost:4318   # optional: Jaeger, Tempo, etc.

Spans follow apab.session > apab.turn > apab.llm.chat / apab.tool.<name> with token counts, latency, cost estimates, and redaction-aware tool arguments. See docs/observability.md for the attribute reference and lab/ for a one-container Jaeger setup.

Agent framework adapters

The MCP tool layer is the stable surface; three frontends drive it:

Examples

Development

# Run all tests
pytest tests/ -v

# Linting and type checking
ruff check src/ tests/
mypy src/apab/

# Prose check for docs (advisory)
scripts/slopcheck.sh

# Run examples
python examples/01_simple_patch_28ghz.py

Disclaimer

This software is provided for educational and research purposes only. Phased-array antenna technology may be subject to export control regulations including the U.S. International Traffic in Arms Regulations (ITAR) and Export Administration Regulations (EAR). Users are solely responsible for ensuring that their use of this tool, including any designs, simulations, or analyses performed, complies with all applicable laws and regulations.

The authors and contributors make no representations regarding the export control status of any outputs produced by this software and assume no liability for any misuse or for any violations of export control regulations arising from its use.

License

MIT

See SPEC.md for the full specification and CHANGELOG.md for release history.