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Palace Width Sweep: Parallel Simulation

Sweep the microstrip width from 5 to 50 um (5 points), run all simulations in parallel on GDSFactory+ cloud using the non-blocking API, then compare S11 and S21 across widths.

Requirements:

  • IHP PDK: uv pip install ihp-gdsfactory
  • GDSFactory+ account for cloud simulation

Define the sweep

import gdsfactoryplus as gfp

pdk = gfp.get_pdk()
pdk.activate()
import numpy as np

widths = np.arange(2, 21, 4)

Build components and configure simulations

import gdsfactory as gf
from ihp import LAYER, PDK, cells

from gsim.common.stack import get_stack
from gsim.palace import DrivenSim

PDK.activate()

stack = get_stack(air_above=300.0)  # auto-detects active PDK

sims = []

for w in widths:
    # Build component
    c = gf.Component()
    r1 = c << cells.straight_metal(length=1000, width=w)

    r = c.get_region(layer=LAYER.TopMetal2drawing)
    r_sized = r.sized(+20000)
    c.add_polygon(r_sized, layer=LAYER.Metal1drawing)
    c.add_ports(r1.ports)

    # Configure simulation
    sim = DrivenSim()
    sim.set_output_dir(f"./palace-sim-w{w:.1f}")
    sim.set_geometry(c)
    sim.set_stack(stack)

    for port in c.ports:
        sim.add_port(
            port.name, from_layer="metal1", to_layer="topmetal2", geometry="via"
        )

    sim.set_driven(fmin=1e9, fmax=100e9, num_points=80)
    sim.mesh(preset="default")

    sims.append(sim)

print(f"Configured {len(sims)} simulations")
22:36:51 | WARNING  | Small conductor feature detected (2.000 um) may be under-resolved by refined_mesh_size=5.000 um. Pass auto_size=True to scale the mesh down.


/tmp/ipykernel_4605/3909240475.py:9: UserWarning: get_stack(air_above/air_below) is deprecated and ignored. Use simulation.set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...).
  stack = get_stack(air_above=300.0)  # auto-detects active PDK


22:36:53 | WARNING  | Absorbing boundary is applied to solid dielectric surfaces (sin, sio2) because the model has no air region, which produces large spurious insertion loss and reflection. Add an airbox via set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...). Note that get_stack(air_above=...) is deprecated and ignored.


22:36:55 | WARNING  | Absorbing boundary is applied to solid dielectric surfaces (sin, sio2) because the model has no air region, which produces large spurious insertion loss and reflection. Add an airbox via set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...). Note that get_stack(air_above=...) is deprecated and ignored.


22:36:57 | WARNING  | Absorbing boundary is applied to solid dielectric surfaces (sin, sio2) because the model has no air region, which produces large spurious insertion loss and reflection. Add an airbox via set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...). Note that get_stack(air_above=...) is deprecated and ignored.


22:36:59 | WARNING  | Absorbing boundary is applied to solid dielectric surfaces (sin, sio2) because the model has no air region, which produces large spurious insertion loss and reflection. Add an airbox via set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...). Note that get_stack(air_above=...) is deprecated and ignored.


22:37:01 | WARNING  | Absorbing boundary is applied to solid dielectric surfaces (sin, sio2) because the model has no air region, which produces large spurious insertion loss and reflection. Add an airbox via set_airbox(margin_x=..., margin_y=..., z_above=..., z_below=...). Note that get_stack(air_above=...) is deprecated and ignored.


Configured 5 simulations

Upload and start all jobs (non-blocking)

# Upload and start all jobs without waiting
job_ids = []
for sim in sims:
    job_id = sim.run(wait=False, check_cache=True)
    job_ids.append(job_id)

print(f"Started {len(job_ids)} jobs: {job_ids}")
Info    : Reading 'palace-sim-w2.0/palace.msh'...
Info    : 5322 nodes
Info    : 35421 elements
Info    : Done reading 'palace-sim-w2.0/palace.msh'
Info    : Reading 'palace-sim-w2.0/palace.msh'...
Info    : 5322 nodes
Info    : 35421 elements
Info    : Done reading 'palace-sim-w2.0/palace.msh'


Cache hit: reusing job 01a08256-fb10-7aa0-ae99-4186d3a49c26
Info    : Reading 'palace-sim-w6.0/palace.msh'...
Info    : 5722 nodes
Info    : 38443 elements
Info    : Done reading 'palace-sim-w6.0/palace.msh'
Info    : Reading 'palace-sim-w6.0/palace.msh'...
Info    : 5722 nodes
Info    : 38443 elements
Info    : Done reading 'palace-sim-w6.0/palace.msh'


Cache hit: reusing job 01a08257-014d-7782-b9b9-fb8f722819bd
Info    : Reading 'palace-sim-w10.0/palace.msh'...
Info    : 5796 nodes
Info    : 39011 elements
Info    : Done reading 'palace-sim-w10.0/palace.msh'
Info    : Reading 'palace-sim-w10.0/palace.msh'...
Info    : 5796 nodes
Info    : 39011 elements
Info    : Done reading 'palace-sim-w10.0/palace.msh'


Cache hit: reusing job 01a08256-f7fb-7360-8480-ccac9ebefc5e
Info    : Reading 'palace-sim-w14.0/palace.msh'...
Info    : 5784 nodes
Info    : 38804 elements
Info    : Done reading 'palace-sim-w14.0/palace.msh'
Info    : Reading 'palace-sim-w14.0/palace.msh'...
Info    : 5784 nodes
Info    : 38804 elements
Info    : Done reading 'palace-sim-w14.0/palace.msh'


Cache hit: reusing job 01a08257-0df7-7371-8877-3b5163c7a787
Info    : Reading 'palace-sim-w18.0/palace.msh'...
Info    : 6115 nodes
Info    : 41268 elements
Info    : Done reading 'palace-sim-w18.0/palace.msh'
Info    : Reading 'palace-sim-w18.0/palace.msh'...
Info    : 6115 nodes
Info    : 41268 elements
Info    : Done reading 'palace-sim-w18.0/palace.msh'


Cache hit: reusing job 01a08257-148a-7732-9092-a70cafb9c2df
Started 5 jobs: ['01a08256-fb10-7aa0-ae99-4186d3a49c26', '01a08257-014d-7782-b9b9-fb8f722819bd', '01a08256-f7fb-7360-8480-ccac9ebefc5e', '01a08257-0df7-7371-8877-3b5163c7a787', '01a08257-148a-7732-9092-a70cafb9c2df']

Wait for all jobs to complete

import gsim

# Poll all jobs concurrently, download and parse results
results = gsim.wait_for_results(job_ids)
Waiting for 5 jobs...
  palace-4f8e1ab1                completed    0m 00s
  palace-e7777c64                completed    0m 00s
  palace-f5ac2225                completed    0m 00s
  palace-fbf9259b                completed    0m 00s
  palace-47647029                completed    0m 00s


Extracting results.tar.gz...
Downloaded 11 files to /home/runner/work/simulation-templates/simulation-templates/docs/notebooks/sim-data-palace-4f8e1ab1


Extracting results.tar.gz...
Downloaded 11 files to /home/runner/work/simulation-templates/simulation-templates/docs/notebooks/sim-data-palace-e7777c64


Extracting results.tar.gz...
Downloaded 11 files to /home/runner/work/simulation-templates/simulation-templates/docs/notebooks/sim-data-palace-f5ac2225


Extracting results.tar.gz...
Downloaded 11 files to /home/runner/work/simulation-templates/simulation-templates/docs/notebooks/sim-data-palace-fbf9259b


Extracting results.tar.gz...
Downloaded 11 files to /home/runner/work/simulation-templates/simulation-templates/docs/notebooks/sim-data-palace-47647029

Plot S11 and S21 comparison

import matplotlib.pyplot as plt

fig, (ax1, ax2) = plt.subplots(2, 1, figsize=(6, 6))

for w, sp in zip(widths, results, strict=True):
    ax1.plot(sp.freq, sp.s11.db, label=f"w={w:.1f} um")
    ax2.plot(sp.freq, sp.s21.db, label=f"w={w:.1f} um")

ax1.set(
    xlabel="Frequency (GHz)", ylabel="|S11| (dB)", title="S11 — Return Loss vs Width"
)
ax1.legend()
ax1.grid(True)

ax2.set(
    xlabel="Frequency (GHz)", ylabel="|S21| (dB)", title="S21 — Insertion Loss vs Width"
)
ax2.legend()
ax2.grid(True)

plt.tight_layout()

png