Antenna matching network

This guide builds an antenna signal path from three Zener elements:

Component() wrappers for the connector and antenna
a reusable matching-network module
a board that connects the complete RF path

The example uses the repository model defined in the language specification: the board calls Board(), reusable blocks live under modules/ and components/, and local modules use relative paths.

Repository layout

Create one package for each reusable block:

my-rf-demo/
├── pcb.toml
├── AntennaDemo.zen
├── modules/
│   └── AntennaMatch/
│       ├── AntennaMatch.zen
│       └── pcb.toml
└── components/
    ├── ChipAntenna/
    │   ├── ChipAntenna.zen
    │   ├── ChipAntenna.kicad_sym
    │   ├── ChipAntenna.kicad_mod
    │   └── pcb.toml
    └── SMAConnector/
        ├── SMAConnector.zen
        ├── SMAConnector.kicad_sym
        ├── SMAConnector.kicad_mod
        └── pcb.toml

The root pcb.toml can be as small as:

[workspace]
pcb-version = "0.4"

[board]
name = "AntennaDemo"
path = "AntennaDemo.zen"
description = "Replace with concise board description."

Use pcb new board and pcb new package to create this structure. The component values below are examples. Select production values from the antenna data, finished PCB stackup, and vector network analyzer measurements.

Before writing Zener source, copy the KiCad symbol and footprint for each physical part into its package directory with the filenames shown above. Zener does not copy these assets from an installed KiCad library. Confirm that the symbol pin names match the wrapper’s pins mapping.

1. Wrap the physical endpoints

Use standard-library generics for common passives. Use a small custom module for the specific SMA connector and antenna. Each wrapper calls Component() once and exposes the required pins through io().

SMA connector

# components/SMAConnector/SMAConnector.zen
CENTER = io(Net, help="Coax center conductor")
SHIELD = io(Ground, help="Coax shield")

prefix = config(str, default="J")

Component(
    name = "SMAConnector",
    symbol = Symbol(
        library = "SMAConnector.kicad_sym",
    ),
    footprint = File("SMAConnector.kicad_mod"),
    prefix = prefix,
    pins = {
        "In": CENTER,
        "Ext": SHIELD,
    },
)

Chip antenna

# components/ChipAntenna/ChipAntenna.zen
FEED = io(Net)

prefix = config(str, default="AE")

Component(
    name = "ChipAntenna",
    symbol = Symbol(
        library = "ChipAntenna.kicad_sym",
    ),
    footprint = File("ChipAntenna.kicad_mod"),
    prefix = prefix,
    pins = {
        "A": FEED,
    },
)

Use raw Component() only when a standard-library generic does not represent the physical part. Standard-library generics provide maintained symbols, footprints, and BOM behavior for the matching components.

Hover over pins in the editor to inspect the pin names loaded from the symbol.

2. Build the matching module

The module reserves three tuning footprints: a series inductor, a shunt capacitor, and a final series resistor. Populate the resistor with a damping value or with 0ohm.

# modules/AntennaMatch/AntennaMatch.zen
load("@stdlib/units.zen", "Capacitance", "Inductance", "Resistance")

Capacitor = Module("@stdlib/generics/Capacitor.zen")
Inductor = Module("@stdlib/generics/Inductor.zen")
Resistor = Module("@stdlib/generics/Resistor.zen")

series_l = config(Inductance, default=Inductance("6.8nH"))
shunt_c = config(Capacitance, default=Capacitance("1.5pF"))
series_r = config(Resistance, default=Resistance("0ohm"))
package = config(str, default="0402")

RF_IN = io(Net, direction="input")
RF_OUT = io(Net, direction="output")
GND = io(Ground)
MATCH_NODE = Net()

Inductor(
    name = "L_SERIES",
    value = series_l,
    package = package,
    P1 = RF_IN,
    P2 = MATCH_NODE,
)

Capacitor(
    name = "C_SHUNT",
    value = shunt_c,
    package = package,
    P1 = MATCH_NODE,
    P2 = GND,
)

Resistor(
    name = "R_SERIES",
    value = series_r,
    package = package,
    P1 = MATCH_NODE,
    P2 = RF_OUT,
)

Layout(name = "AntennaMatch", path = "layout/AntennaMatch")

Use io() for parent connections and Net() for internal nodes such as MATCH_NODE.

The declared config() types convert parent-supplied strings such as "6.8nH", "1.5pF", and "0ohm" to physical quantities.

3. Compose the board

Instantiate the connector, matching network, and antenna in the board file:

# AntennaDemo.zen
SMAConnector = Module("./components/SMAConnector/SMAConnector.zen")
ChipAntenna = Module("./components/ChipAntenna/ChipAntenna.zen")
AntennaMatch = Module("./modules/AntennaMatch/AntennaMatch.zen")

rf_source = Net("RF_SOURCE")
rf_feed = Net("RF_FEED")
gnd = Ground("GND")

SMAConnector(
    name = "J_RF",
    CENTER = rf_source,
    SHIELD = gnd,
)

AntennaMatch(
    name = "MATCH",
    RF_IN = rf_source,
    RF_OUT = rf_feed,
    GND = gnd,
    series_l = "6.8nH",
    shunt_c = "1.5pF",
    series_r = "0ohm",
    package = "0402",
    schematic = "embed",
)

ChipAntenna(
    name = "AE1",
    FEED = rf_feed,
)

Board(
    name = "AntennaDemo",
    layers = 2,
    layout_path = "layout/AntennaDemo",
)

The resulting RF path is:

SMA center -> series inductor -> tuning node -> series resistor -> antenna feed
                                 |
                            shunt capacitor
                                 |
                               ground

4. Build and lay out the board

Run these commands from the repository root:

pcb build AntennaDemo.zen
pcb layout AntennaDemo.zen

pcb build validates the design. pcb layout generates the KiCad board and opens it for placement and routing.

RF performance depends on placement and stackup. Place the matching components close to the antenna feed, route the RF trace for the required impedance, and leave access for component changes during bringup.

Optional mounting holes

Add mounting holes with the standard-library generic:

MountingHole = Module("@stdlib/generics/MountingHole.zen")

for i in range(4):
    MountingHole(
        name = "H" + str(i + 1),
        diameter = "M2",
    )

Run pcb layout again, then place the holes to satisfy the enclosure and copper keep-out requirements.

Design rationale

The antenna and connector packages contain only physical-part definitions.
The matching network owns the topology and tuning values.
The board file contains only board-level composition.

This separation permits changes to matching values, footprints, or the antenna package without changing board-level connectivity.

Toolchain

Registry

Examples

Repository layout

1. Wrap the physical endpoints

SMA connector

Chip antenna

2. Build the matching module

3. Compose the board

4. Build and lay out the board

Optional mounting holes

Design rationale

​Repository layout

​1. Wrap the physical endpoints

​SMA connector

​Chip antenna

​2. Build the matching module

​3. Compose the board

​4. Build and lay out the board

​Optional mounting holes

​Design rationale

Repository layout

1. Wrap the physical endpoints

SMA connector

Chip antenna

2. Build the matching module

3. Compose the board

4. Build and lay out the board

Optional mounting holes

Design rationale