Antenna Symbol
Definition: The Antenna symbol represents a transducer that converts between guided electromagnetic waves (in a transmission line) and free-space radio waves, drawn in IEC 60617-07 as a vertical line with radiating diagonal strokes or a triangle above a horizontal base, and in ANSI/IEEE 315-1975 as a similar mast-with-strokes or dipole representation, with the single feed pin connecting to the RF circuit.
Also known as: aerial, RF antenna, radio antenna, wireless antenna, antenna symbol, aerial symbol.
What the Antenna symbol means
The Antenna symbol in a circuit diagram marks the point where an electrical circuit interfaces with the electromagnetic environment. In transmitter circuits, the antenna symbol shows where RF power leaves the circuit and is radiated as radio waves. In receiver circuits, it marks the point where incoming radio-frequency energy is captured and fed into the front-end amplifier or tuner.
Antenna symbols appear on every wireless circuit schematic — from simple AM/FM radios to cellular, Wi-Fi, Bluetooth, and satellite communication systems. The symbol does not specify the antenna's physical form (dipole, monopole, patch, Yagi, helical) unless annotated; it simply indicates an RF connection point to free space. The designator prefix is typically E or ANT (e.g., ANT1).
How to identify the Antenna symbol
The standard Antenna symbol is a vertical line (the mast or feedline) with two or three short diagonal lines radiating outward from the top at approximately 45°, forming a stylised broadcasting or receiving structure. Some variants show a plain inverted triangle above the feedline (representing a dipole or ground-plane antenna). The symbol has a single feed pin at the bottom of the vertical line. Yagi and directional antenna symbols add horizontal element lines to the mast. In schematics for PCB design, the antenna symbol is often accompanied by the reference designator 'ANT1' or 'E1' and a note giving the antenna type, impedance (typically 50 Ω), and frequency band.
Function and usage boundary
An antenna converts electrical power into radiated electromagnetic energy (transmitting) or converts received electromagnetic energy into an electrical signal (receiving). The antenna symbol in a schematic indicates where the RF signal path ends and free-space propagation begins. Impedance matching between the antenna (typically 50 Ω for coaxial systems) and the transmitter/receiver is critical; a mismatch causes reflections measured by the voltage standing wave ratio (VSWR). Baluns, matching networks, or antenna tuners are often shown between the transceiver symbol and the antenna symbol.
Standards: IEC vs ANSI
| IEC 60617 | IEC 60617-07:1996 (Graphical symbols for diagrams — Part 7: Switchgear, controlgear and protective devices / also includes RF/HF symbols) and IEC 60617-09 define the antenna symbol as a vertical line with radiating strokes or a triangle. The basic symbol code is 07-04-01 (aerial/antenna). |
|---|---|
| ANSI/IEEE 315 | ANSI/IEEE 315-1975 Section 4 defines the antenna symbol similarly: a vertical element with diagonal radiating lines. Variants for dipole, loop, and directional antennas are distinguished by additional strokes. The standard designator is ANT or E. |
| Key difference | IEC 60617 and ANSI/IEEE 315 antenna symbols are functionally identical; both use radiating-stroke mast conventions. Minor differences exist in the number and angle of radiating strokes. IEC sometimes uses a plain triangle (▲) on a line for an omnidirectional antenna; ANSI uses the mast-with-strokes more consistently. |
The displayed SVG is the live editor implementation, not a licensed reproduction or certification of an IEC or IEEE database glyph. Verify the exact official entry and project edition before issuing work.
Logical terminals
| Logical ID | Editor terminal name |
|---|---|
| feed | Feed |
Where the Antenna symbol is used
- RF transmitter output stage schematics showing the connection between power amplifier and radiating element
- Wireless receiver input schematics (Wi-Fi, Bluetooth, Zigbee, LoRa, cellular) marking the antenna feed point
- PCB schematics for modules with an integrated PCB trace antenna or external SMA/U.FL connector
- Radio telescope and satellite communication ground station circuit diagrams
- RFID reader and tag circuit diagrams showing the antenna coil connection
- Amateur radio (ham radio) transceiver schematics including tuner and balun sections
- Automotive telematics and keyless entry system schematics
Key facts
- The Antenna symbol represents an RF transducer that converts between electrical signals in a circuit and electromagnetic waves in free space, as defined in IEC 60617-07 and ANSI/IEEE 315-1975.
- The symbol is drawn as a vertical line (feedline) topped with two or three diagonal radiating strokes at approximately 45°, or alternatively as an inverted triangle above a baseline for a dipole-style representation.
- The single pin on the antenna symbol is the feed point (labelled 'Feed' in this schematic system) and connects to the RF signal path; it has a characteristic impedance of 50 Ω in most coaxial-feed systems.
- The schematic designator for an antenna is ANT (e.g., ANT1) or E (e.g., E1) per ANSI/IEEE 315; 'ANT' is more common in modern PCB design tools.
- Antenna symbols do not specify the physical antenna type; the type (dipole, monopole, patch, Yagi, helical, loop) is conveyed through a text note or a specific variant symbol with additional strokes or elements.
- Impedance matching between the antenna (typically 50 Ω) and the RF circuit is critical; VSWR should be below 2:1 for efficient power transfer, and mismatch causes reflected power measured in dB return loss.
- In multi-antenna diversity systems (MIMO), the schematic will show multiple antenna symbols labelled ANT1, ANT2, etc., each connected to separate RF paths or a diversity switch.
- The antenna symbol also appears on logic-level schematics for wireless modules (ESP8266, nRF24L01, LoRa) where it simply marks the external antenna connection pad rather than a full RF circuit.
Diagrams that use this symbol
- car audio wiring diagram
- car stereo wiring diagram
- car radio connection diagram
- car radio wiring diagram
- radio wiring diagram
- stereo wiring diagram
- amplifier connection diagram
- block diagram of digital communication system
Frequently asked questions
What does the antenna symbol look like in a circuit diagram?
The antenna symbol is a vertical line (feedline) with two or three short diagonal lines radiating outward from the top at roughly 45°, resembling a broadcasting mast. A variant shows an inverted triangle above a horizontal base. The single connection pin is at the bottom of the vertical line where it meets the circuit.
What does the antenna symbol mean in a schematic?
The antenna symbol marks the point where the electrical circuit connects to free space for wireless signal transmission or reception. In transmitter circuits it shows where RF power is radiated; in receiver circuits it shows where incoming radio energy enters the circuit.
What is the IEC vs ANSI difference for antenna symbols?
Both IEC 60617-07 and ANSI/IEEE 315-1975 use a vertical mast with radiating strokes for the antenna symbol. IEC sometimes uses a plain triangle (▲) on a vertical line for omnidirectional antennas; ANSI uses the mast-with-strokes convention more consistently. Functionally the two representations are identical.
What is the designator letter for an antenna?
The standard designator for an antenna is ANT (e.g., ANT1) or E (e.g., E1) per ANSI/IEEE 315-1975. Modern PCB design tools and datasheets most commonly use ANT. The letter E comes from the older convention of treating the antenna as an 'electric field element'.
What standard defines the antenna symbol?
The antenna symbol is defined in IEC 60617-07:1996 (symbol code 07-04-01) and ANSI/IEEE 315-1975 Section 4. Both standards describe the mast-with-radiating-strokes convention. The symbol is widely reproduced in datasheets, schematics, and PCB design tools without modification.
What is the impedance of the antenna symbol's feed pin?
The antenna feed pin in most RF circuit schematics is 50 Ω, which is the standard characteristic impedance for coaxial transmission lines and RF connectors (SMA, BNC, SMA). Balanced antenna systems (dipoles with twin-lead feed) use 300 Ω, and a balun is shown in the schematic when the circuit is unbalanced (50 Ω) but the antenna is balanced.
What are the common variants of the antenna symbol?
Common antenna symbol variants include: the basic omnidirectional mast with radiating strokes (general antenna), the dipole symbol (two horizontal lines forming a balanced pair), the loop antenna (circular symbol), the dish/directional symbol (curved reflector with feed), and the Yagi symbol (multiple horizontal elements on a boom). Each variant indicates a different radiation pattern or antenna type.
Related symbols
- Balun symbol
- Colpitts Oscillator symbol
- Directional Coupler symbol
- LoRa Module symbol
- nRF24L01 RF Module symbol
- RF Attenuator symbol
Physical breadboard, PCB, and panel mapping
No universal physical profile is published for this symbol yet. Create a versioned custom part from the exact manufacturer dimensions and terminal map before fabrication.
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