Files
PLFM_RADAR/9_Firmware/9_3_GUI/adi_agc_analysis.py
T
Jason 609589349d fix: range calibration, demo/radar mutual exclusion, AGC analysis refactor
Bug #1 — Range calibration for Raw IQ Replay:
- Add WaveformConfig dataclass (models.py) with FMCW waveform params
  (fs, BW, T_chirp, fc) and methods to compute range/velocity resolution
- Add waveform parameter spinboxes to playback controls (dashboard.py)
- Auto-parse waveform params from ADI phaser filename convention
- Create replay-specific RadarSettings with correct calibration instead
  of using FPGA defaults (781.25 m/bin → 0.334 m/bin for ADI phaser)
- Add 4 unit tests validating WaveformConfig math

Bug #2 — Demo + radar mutual exclusion:
- _start_demo() now refuses if radar is running (_running=True)
- _start_radar() stops demo first if _demo_mode is active
- Demo buttons disabled while radar/replay is running, re-enabled on stop

Bug #3 — Refactor adi_agc_analysis.py:
- Remove 60+ lines of duplicated AGC functions (signed_to_encoding,
  encoding_to_signed, clamp_gain, apply_gain_shift)
- Import from v7.agc_sim canonical implementation
- Rewrite simulate_agc() to use process_agc_frame() in a loop
- Rewrite process_frame_rd() to use quantize_iq() from agc_sim
2026-04-14 03:19:58 +05:45

339 lines
13 KiB
Python

# ruff: noqa: T201
#!/usr/bin/env python3
"""
One-off AGC saturation analysis for ADI CN0566 raw IQ captures.
Bit-accurate simulation of rx_gain_control.v AGC inner loop applied
to real captured IQ data. Three scenarios per dataset:
Row 1 — AGC OFF: Fixed gain_shift=0 (pass-through). Shows raw clipping.
Row 2 — AGC ON: Auto-adjusts from gain_shift=0. Clipping clears.
Row 3 — AGC delayed: OFF for first half, ON at midpoint.
Shows the transition: clipping → AGC activates → clears.
Key RTL details modelled exactly:
- gain_shift[3]=direction (0=amplify/left, 1=attenuate/right), [2:0]=amount
- Internal agc_gain is signed -7..+7
- Peak is measured PRE-gain (raw input |sample|, upper 8 of 15 bits)
- Saturation is measured POST-gain (overflow from shift)
- Attack: gain -= agc_attack when any sample clips (immediate)
- Decay: gain += agc_decay when peak < target AND holdoff expired
- Hold: when peak >= target AND no saturation, hold gain, reset holdoff
Usage:
python adi_agc_analysis.py
python adi_agc_analysis.py --data /path/to/file.npy --label "my capture"
"""
import argparse
import sys
from pathlib import Path
import matplotlib.pyplot as plt
import numpy as np
from v7.agc_sim import (
encoding_to_signed,
apply_gain_shift,
quantize_iq,
AGCConfig,
AGCState,
process_agc_frame,
)
# ---------------------------------------------------------------------------
# FPGA AGC parameters (rx_gain_control.v reset defaults)
# ---------------------------------------------------------------------------
AGC_TARGET = 200 # host_agc_target (8-bit, default 200)
ADC_RAIL = 4095 # 12-bit ADC max absolute value
# ---------------------------------------------------------------------------
# Per-frame AGC simulation using v7.agc_sim (bit-accurate to RTL)
# ---------------------------------------------------------------------------
def simulate_agc(frames: np.ndarray, agc_enabled: bool = True,
enable_at_frame: int = 0,
initial_gain_enc: int = 0x00) -> dict:
"""Simulate FPGA inner-loop AGC across all frames.
Parameters
----------
frames : (N, chirps, samples) complex — raw ADC captures (12-bit range)
agc_enabled : if False, gain stays fixed
enable_at_frame : frame index where AGC activates
initial_gain_enc : gain_shift[3:0] encoding when AGC enables (default 0x00 = pass-through)
"""
n_frames = frames.shape[0]
# Output arrays
out_gain_enc = np.zeros(n_frames, dtype=int)
out_gain_signed = np.zeros(n_frames, dtype=int)
out_peak_mag = np.zeros(n_frames, dtype=int)
out_sat_count = np.zeros(n_frames, dtype=int)
out_sat_rate = np.zeros(n_frames, dtype=float)
out_rms_post = np.zeros(n_frames, dtype=float)
# AGC state — managed by process_agc_frame()
state = AGCState(
gain=encoding_to_signed(initial_gain_enc),
holdoff_counter=0,
was_enabled=False,
)
for i in range(n_frames):
frame_i, frame_q = quantize_iq(frames[i])
agc_active = agc_enabled and (i >= enable_at_frame)
# Build per-frame config (enable toggles at enable_at_frame)
config = AGCConfig(enabled=agc_active)
result = process_agc_frame(frame_i, frame_q, config, state)
# RMS of shifted signal
rms = float(np.sqrt(np.mean(
result.shifted_i.astype(np.float64)**2
+ result.shifted_q.astype(np.float64)**2)))
total_samples = frame_i.size + frame_q.size
sat_rate = result.overflow_raw / total_samples if total_samples > 0 else 0.0
# Record outputs
out_gain_enc[i] = result.gain_enc
out_gain_signed[i] = result.gain_signed
out_peak_mag[i] = result.peak_mag_8bit
out_sat_count[i] = result.saturation_count
out_sat_rate[i] = sat_rate
out_rms_post[i] = rms
return {
"gain_enc": out_gain_enc,
"gain_signed": out_gain_signed,
"peak_mag": out_peak_mag,
"sat_count": out_sat_count,
"sat_rate": out_sat_rate,
"rms_post": out_rms_post,
}
# ---------------------------------------------------------------------------
# Range-Doppler processing for heatmap display
# ---------------------------------------------------------------------------
def process_frame_rd(frame: np.ndarray, gain_enc: int,
n_range: int = 64,
n_doppler: int = 32) -> np.ndarray:
"""Range-Doppler magnitude for one frame with gain applied."""
frame_i, frame_q = quantize_iq(frame)
si, sq, _ = apply_gain_shift(frame_i, frame_q, gain_enc)
iq = si.astype(np.float64) + 1j * sq.astype(np.float64)
n_chirps, _ = iq.shape
range_fft = np.fft.fft(iq, axis=1)[:, :n_range]
doppler_fft = np.fft.fftshift(np.fft.fft(range_fft, axis=0), axes=0)
center = n_chirps // 2
half_d = n_doppler // 2
doppler_fft = doppler_fft[center - half_d:center + half_d, :]
rd_mag = np.abs(doppler_fft.real) + np.abs(doppler_fft.imag)
return rd_mag.T # (n_range, n_doppler)
# ---------------------------------------------------------------------------
# Plotting
# ---------------------------------------------------------------------------
def plot_scenario(axes, data: np.ndarray, agc: dict, title: str,
enable_frame: int = 0):
"""Plot one AGC scenario across 5 axes."""
n = data.shape[0]
xs = np.arange(n)
# Range-Doppler heatmap
if enable_frame > 0 and enable_frame < n:
f_before = max(0, enable_frame - 1)
f_after = min(n - 1, n - 2)
rd_before = process_frame_rd(data[f_before], int(agc["gain_enc"][f_before]))
rd_after = process_frame_rd(data[f_after], int(agc["gain_enc"][f_after]))
combined = np.hstack([rd_before, rd_after])
im = axes[0].imshow(
20 * np.log10(combined + 1), aspect="auto", origin="lower",
cmap="inferno", interpolation="nearest")
axes[0].axvline(x=rd_before.shape[1] - 0.5, color="cyan",
linewidth=2, linestyle="--")
axes[0].set_title(f"{title}\nL: f{f_before} (pre) | R: f{f_after} (post)")
else:
worst = int(np.argmax(agc["sat_count"]))
best = int(np.argmin(agc["sat_count"]))
f_show = worst if agc["sat_count"][worst] > 0 else best
rd = process_frame_rd(data[f_show], int(agc["gain_enc"][f_show]))
im = axes[0].imshow(
20 * np.log10(rd + 1), aspect="auto", origin="lower",
cmap="inferno", interpolation="nearest")
axes[0].set_title(f"{title}\nFrame {f_show}")
axes[0].set_xlabel("Doppler bin")
axes[0].set_ylabel("Range bin")
plt.colorbar(im, ax=axes[0], label="dB", shrink=0.8)
# Signed gain history (the real AGC state)
axes[1].plot(xs, agc["gain_signed"], color="#00ff88", linewidth=1.5)
axes[1].axhline(y=0, color="gray", linestyle=":", alpha=0.5,
label="Pass-through")
if enable_frame > 0:
axes[1].axvline(x=enable_frame, color="yellow", linewidth=2,
linestyle="--", label="AGC ON")
axes[1].set_ylim(-8, 8)
axes[1].set_ylabel("Gain (signed)")
axes[1].set_title("AGC Internal Gain (-7=max atten, +7=max amp)")
axes[1].legend(fontsize=7, loc="upper right")
axes[1].grid(True, alpha=0.3)
# Peak magnitude (PRE-gain, 8-bit)
axes[2].plot(xs, agc["peak_mag"], color="#ffaa00", linewidth=1.0)
axes[2].axhline(y=AGC_TARGET, color="cyan", linestyle="--",
alpha=0.7, label=f"Target ({AGC_TARGET})")
axes[2].axhspan(240, 255, color="red", alpha=0.15, label="Clip zone")
if enable_frame > 0:
axes[2].axvline(x=enable_frame, color="yellow", linewidth=2,
linestyle="--", alpha=0.8)
axes[2].set_ylim(0, 260)
axes[2].set_ylabel("Peak (8-bit)")
axes[2].set_title("Peak Magnitude (pre-gain, raw input)")
axes[2].legend(fontsize=7, loc="upper right")
axes[2].grid(True, alpha=0.3)
# Saturation count (POST-gain overflow)
axes[3].fill_between(xs, agc["sat_count"], color="red", alpha=0.4)
axes[3].plot(xs, agc["sat_count"], color="red", linewidth=0.8)
if enable_frame > 0:
axes[3].axvline(x=enable_frame, color="yellow", linewidth=2,
linestyle="--", alpha=0.8)
axes[3].set_ylabel("Overflow Count")
total = int(agc["sat_count"].sum())
axes[3].set_title(f"Post-Gain Overflow (total={total})")
axes[3].grid(True, alpha=0.3)
# RMS signal level (post-gain)
axes[4].plot(xs, agc["rms_post"], color="#44aaff", linewidth=1.0)
if enable_frame > 0:
axes[4].axvline(x=enable_frame, color="yellow", linewidth=2,
linestyle="--", alpha=0.8)
axes[4].set_ylabel("RMS")
axes[4].set_xlabel("Frame")
axes[4].set_title("Post-Gain RMS Level")
axes[4].grid(True, alpha=0.3)
def analyze_dataset(data: np.ndarray, label: str):
"""Run 3-scenario analysis for one dataset."""
n_frames = data.shape[0]
mid = n_frames // 2
print(f"\n{'='*60}")
print(f" {label} — shape {data.shape}")
print(f"{'='*60}")
# Raw ADC stats
raw_sat = np.sum((np.abs(data.real) >= ADC_RAIL) |
(np.abs(data.imag) >= ADC_RAIL))
print(f" Raw ADC saturation: {raw_sat} samples "
f"({100*raw_sat/(2*data.size):.2f}%)")
# Scenario 1: AGC OFF — pass-through (gain_shift=0x00)
print(" [1/3] AGC OFF (gain=0, pass-through) ...")
agc_off = simulate_agc(data, agc_enabled=False, initial_gain_enc=0x00)
print(f" Post-gain overflow: {agc_off['sat_count'].sum()} "
f"(should be 0 — no amplification)")
# Scenario 2: AGC ON from frame 0
print(" [2/3] AGC ON (from start) ...")
agc_on = simulate_agc(data, agc_enabled=True, enable_at_frame=0,
initial_gain_enc=0x00)
print(f" Final gain: {agc_on['gain_signed'][-1]} "
f"(enc=0x{agc_on['gain_enc'][-1]:X})")
print(f" Post-gain overflow: {agc_on['sat_count'].sum()}")
# Scenario 3: AGC delayed
print(f" [3/3] AGC delayed (ON at frame {mid}) ...")
agc_delayed = simulate_agc(data, agc_enabled=True,
enable_at_frame=mid,
initial_gain_enc=0x00)
pre_sat = int(agc_delayed["sat_count"][:mid].sum())
post_sat = int(agc_delayed["sat_count"][mid:].sum())
print(f" Pre-AGC overflow: {pre_sat} "
f"Post-AGC overflow: {post_sat}")
# Plot
fig, axes = plt.subplots(3, 5, figsize=(28, 14))
fig.suptitle(f"AERIS-10 AGC Analysis — {label}\n"
f"({n_frames} frames, {data.shape[1]} chirps, "
f"{data.shape[2]} samples/chirp, "
f"raw ADC sat={100*raw_sat/(2*data.size):.2f}%)",
fontsize=13, fontweight="bold", y=0.99)
plot_scenario(axes[0], data, agc_off, "AGC OFF (pass-through)")
plot_scenario(axes[1], data, agc_on, "AGC ON (from start)")
plot_scenario(axes[2], data, agc_delayed,
f"AGC delayed (ON at frame {mid})", enable_frame=mid)
for ax, lbl in zip(axes[:, 0],
["AGC OFF", "AGC ON", "AGC DELAYED"],
strict=True):
ax.annotate(lbl, xy=(-0.35, 0.5), xycoords="axes fraction",
fontsize=13, fontweight="bold", color="white",
ha="center", va="center", rotation=90)
plt.tight_layout(rect=[0.03, 0, 1, 0.95])
return fig
def main():
parser = argparse.ArgumentParser(
description="AGC analysis for ADI raw IQ captures "
"(bit-accurate rx_gain_control.v simulation)")
parser.add_argument("--amp", type=str,
default=str(Path.home() / "Downloads/adi_radar_data"
"/amp_radar"
"/phaser_amp_4MSPS_500M_300u_256_m3dB.npy"),
help="Path to amplified radar .npy")
parser.add_argument("--noamp", type=str,
default=str(Path.home() / "Downloads/adi_radar_data"
"/no_amp_radar"
"/phaser_NOamp_4MSPS_500M_300u_256.npy"),
help="Path to non-amplified radar .npy")
parser.add_argument("--data", type=str, default=None,
help="Single dataset mode")
parser.add_argument("--label", type=str, default="Custom Data")
args = parser.parse_args()
plt.style.use("dark_background")
if args.data:
data = np.load(args.data)
analyze_dataset(data, args.label)
plt.show()
return
figs = []
for path, label in [(args.amp, "With Amplifier (-3 dB)"),
(args.noamp, "No Amplifier")]:
if not Path(path).exists():
print(f"WARNING: {path} not found, skipping")
continue
data = np.load(path)
fig = analyze_dataset(data, label)
figs.append(fig)
if not figs:
print("No data found. Use --amp/--noamp or --data.")
sys.exit(1)
plt.show()
if __name__ == "__main__":
main()