The side mount dipole antenna is a vertically polarized VHF/UHF antenna designed for mounting on the side of a tower or mast. Rather than at its top. Antenna Experts manufactures the SMD series of omni-directional side-mount dipole antennas covering 30 MHz to 512 MHz, with a 3 dB gain, low VSWR, and marine-grade construction. All SMD antennas are designed and manufactured in-house in India for use in base stations, communication towers, coastal or shipboard sites. We can build bands outside of the standard range upon request.
What is a Side Mount Dipole Antenna?
A side-mount dipole antenna is a centre-fed dipole mounted to the side of a tower structure, rather than sitting on top of it. This matters in practice: tower tops are crowded, and side mounting lets multiple antennas share a single structure without competing for the summit position.
The SMD series antennas are exposed open dipoles designed for vertically polarized waves, delivering an omni-directional pattern with 3 dBd gain. They are mounted in vertical polarization on the side of a tower using the supplied stainless steel hardware, and a central mast is included with the antenna.
Key Features & Specifications
The SMD series covers the full VHF and UHF span in dedicated frequency bands. Each band has 3 dBd omni-directional gain and low VSWR across the entire band.
Parameter and Specification
Frequency bands — 30–66 MHz, 66–88 MHz, 134–174 MHz, 220–290 MHz, 300–400 MHz, 406–512 MHz
Gain — 3 dBd, omni-directional
Polarization — Vertical
VSWR — Low across the full band
Boom / elements — 6063-T6 anodized aluminium, ultra corrosion resistant
Fasteners — Type 316 marine grade stainless steel
Termination — N-Female, sealed in flame-retardant heat shrink
Weatherproofing — Balun and dipole connections sealed in epoxy
Lightning protection — Low-resistance discharge path through tubular boom
Models — SMD-50, SMD-75, SMD-150, SMD-450 and others
There are two design points worth highlighting. The wide azimuth and elevation beamwidth results in excellent null fill, resulting in consistent coverage without dead zones close to the tower. Additionally, marine-grade stainless fasteners and epoxy-sealed balun and dipole connections make every Side Mount Dipole Antennas a marine variant as standard - suitable for coastal and shipboard installations where salt air destroys ordinary hardware.
The application
Sites with base stations and repeaters - omni-directional coverage from side-mounted towers
Communications networks using VHF and UHF frequencies ranging from 30 MHz to 512 MHz
Corrosion-resistant construction is a standard feature of marine and coastal installations
High gain military grade variants are available for military and tactical communications
The 136-174 MHz and 406-512 MHz bands provide reliable omni-coverage for public safety and land mobile radio.
Towers with multiple antennas - side mounting allows the tower top to be used for other equipment
30–512 MHz cover the common VHF/UHF communication, tactical, and land mobile bands.
Why Choose Antenna Experts?
An antenna that must survive for many years on an exposed tower should have a high level of construction quality.
Antenna Experts designs and manufactures the SMD series in-house in India. The boom and elements are made from corrosion-resistant architectural anodized aluminum 6063-T6. The fasteners are all made of stainless steel type 316 marine grade. The centre-fed dipole ends and cable connections are sealed in epoxy at the end of the boom, which waterproofs the connection and adds rigidity to the dipole structure. The N-Female termination is sealed in flame-retardant heat shrink tubing for complete waterproofing.
The tubular aluminium boom carries a low-resistance discharge path, protecting the installation against lightning strikes during storms — an important concern for any tower-mounted antenna.
Because design and production are in-house, Antenna Experts also builds side mount dipole antennas for frequency bands outside the standard range. As a side mount dipole antenna manufacturer, supplier and exporter, the company handles custom design, finishing and international delivery as routine work.
Customization options
Frequency band — antennas designed and supplied for bands outside the standard 30–512 MHz range
Central mast — supplied as standard, or the antenna can be supplied without it
Mounting hardware — configure for your tower or mast
Connector — specified to your system
Military grade variants — high gain military specification available
Send your band and site requirements and the antenna will be built around them.
Frequently Asked Questions
What frequency bands does the SMD series cover?
Antenna Experts manufactures side-mount dipole antennas for 30–66 MHz, 66–88 MHz, 134–174 MHz, 220–290 MHz, 300–400 MHz, and 406–512 MHz. Bands outside this range can be designed and supplied on request.
What gain does a side-mounted dipole antenna provide?
The SMD series delivers 3 dBd omni-directional gain with low VSWR across the full band, together with wide azimuth and elevation beamwidth for excellent null fill and consistent coverage.
Why install a dipole on the side of a tower instead of the top?
Side mounting frees the tower top for other equipment and allows several antennas to share one structure. The SMD series is designed for vertical polarization when side-mounted, using the supplied stainless steel hardware.
Are these antennas suitable for marine environments?
Yes. All SMD series antennas are marine variants as standard. They are built with 6063-T6 anodized aluminium and type 316 high grade stainless fasteners, with the balun and dipole connections sealed in epoxy for complete waterproofing.
Is the antenna protected from lightning?
Yes. The dipoles are mounted on a tubular high-strength aluminium boom which provides a low-resistance discharge path against lightning strikes during stormy weather.
Get a Quote or Custom Design
Choosing a side-mount dipole antenna comes down to your frequency band, the coverage pattern your site needs, and whether the environment demands marine-grade protection. The SMD series answers all three: dedicated bands from 30 to 512 MHz, 3 dBd omni-directional coverage with strong null fill, and corrosion-resistant construction as standard rather than an upgrade.