Understanding How Antennas Transmit and Receive Signals in Modern Electronics

Posted on August 1, 2025 Kyle Salem Aircraft Parts

Satellite communications, mobile networks, GPS navigation, and other capabilities are all made possible through the use of antennas. These components are built to facilitate the invisible exchange of signals that powers countless systems we rely on every day. In this blog, we will take a closer look at how antennas are built and the process of transmitting and receiving electromagnetic waves, as well as the components that support their performance.

How Antennas Are Built

While there are always variations, most modern antennas share a set of common design elements:

Conductive Elements: Typically composed of copper, aluminum, or other conductive metals, these elements form the radiating and receiving surfaces of the antenna.
Dielectric Materials: These materials are used to separate conductive sections or support insulation, helping manage signal propagation.
Ground Planes: A ground plane reflects radio waves to boost radiation efficiency.
Feed Line or Connector: This connective component delivers energy from a transmitter to the antenna or carries received signals back to the receiver.

Design Considerations

Antennas are carefully built to align with their intended use, with considerations including:

Frequency Band: The operating frequency determines the wavelength of the signal, which influences the antenna’s physical dimensions. As such, an antenna is usually designed with a length that is proportional to the signal's wavelength.
Gain and Directivity: Gain measures how well an antenna focuses energy, while directivity indicates its preferred signal direction.
Polarization: Polarization refers to the orientation of the electric field, which must align with the intended receiving or transmitting antenna.
Impedance Matching: Proper impedance matching ensures minimal signal reflection and maximum power transfer.

The Process of Transmitting and Receiving

Step 1: Transmission of Electromagnetic Waves

When an antenna is connected to a signal source, such as a radio transmitter or RF generator, it receives an alternating electrical current that causes electrons to oscillate within the antenna’s conductive elements. In turn, it generates a time-varying electromagnetic (EM) field. As this field builds and collapses, it radiates energy outward from the antenna in the form of radio waves, which are electric and magnetic fields that oscillate at right angles to each other and to the direction of wave propagation.

Step 2: Reception of Incoming Signals

When receiving, an antenna behaves in reverse. Incoming radio waves induce a voltage across the antenna's conductive elements, routing it through the feed line to a receiver that demodulates and processes the signal. Notably, the antenna has to be resonant at the desired frequency range to effectively detect and capture the signal energy.

Components That Pair with Antennas

Antennas cannot operate in complete isolation, instead operating as part of a broader system that tends to include supporting components like:

Transceivers: Transceivers combine transmitting and receiving functions, being the primary interface between the antenna and the rest of the communication system.
RF Amplifiers: Positioned between the signal source and the antenna or between the antenna and receiver, RF amplifiers increase signal strength to improve both transmission range and reception clarity.
Matching Networks: Installed between the antenna and feed line, matching networks adjust impedance levels to lessen signal reflection and uphold efficient power transfer.
Filters: Often integrated between the antenna and receiver, filters reduce interference from external sources and eliminate unwanted frequencies.
Coaxial Cables or Waveguides: These transmission lines connect antennas to RF equipment, carrying high-frequency signals while shielding them from interference.

Different Antenna Variants

Antenna Type	Key Characteristics	Standard Applications
Dipole Antenna	Symmetrical, straight-wire design with two conductive elements	Radio, television, RF testing
Monopole Antenna	Single vertical element above a ground plane, half the size of a dipole with similar behavior	Car radios, mobile base stations
Parabolic Dish	Curved reflector dish with a central feed antenna, focuses signals into a narrow beam	Satellite communications, radar systems
Patch(Microstrip)	Flat, surface-mountable antenna mounted on a dielectric substrate	Mobile devices, aircraft systems, GPS receivers
Helical Antenna	Conductor wound in a helical form, providing circular polarization and a wide bandwidth	Spacecraft, satellite communication

Choose a Dependable Source for Antennas and Related Components

In summary, understanding how antennas transmit and receive signals—alone and in conjunction with surrounding devices—is essential whether working on consumer electronics or aerospace platforms. Their specific design and implementation with support components directly affect aspects like signal quality and coverage range, making it vital to seek out the most reliable products that align with a given device or system’s needs. ASAP Semiconductor stands ready to meet these demands with a vast selection of antennas and supporting hardware.

Each item available through ASAP Semiconductor is sourced from established and vetted manufacturers, and we validate conformance with industry and application standards through various means. As a dedicated procurement partner, those who shop with us benefit not only from an expansive inventory, but also from one-on-one support and curated fulfillment options that save time and money. To explore our top-notch antenna options and more, check out our stock today!