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ON-LINE RESOURCES

• Latest News

• Data Guides

• Application Notes

• Knowledge Base

• Software Updates

If you have questions regarding any Linx product and have Internet access,

make www.linxtechnologies.com your first stop. Our website is organized in an

intuitive format to give you the answers you need in record time. Day or night,

the Linx website gives you instant access to the latest information regarding the

products and services of Linx. It's all here: manual and software updates,

application notes, a comprehensive knowledge base, FCC information and much

more. Be sure to visit often!

www.antennafactor.com

The Antenna Factor division of Linx offers

a diverse array of antenna styles, many of

which are optimized for use with our RF

modules. From innovative embeddable

antennas to low-cost whips, domes to

yagi's, and even GPS, Antenna Factor

likely offers or can design an antenna to

meet your requirements.

www.connectorcity.com

Through its Connector City division, Linx offers a wide

selection of high-quality RF connectors, including FCC-

compliant types such as RP-SMAs that are an ideal

match for our modules and antennas. Connector City

focuses on high-volume OEM requirements, which

allows standard and custom RF connectors to be offered

at a remarkably low cost.

www.linxtechnologies.com

A whip-style antenna provides outstanding overall performance

and stability. A low-cost whip is can be easily fabricated from a

wire or rod, but most designers opt for the consistent

performance and cosmetic appeal of a professionally made

model. To meet this need, Linx offers a wide variety of straight

and reduced height whip-style antennas in permanent and

connectorized mounting styles.

The wavelength of the operational frequency determines an

antenna’s overall length. Since a full wavelength is often quite

long, a partial 1/2- or 1/4-wave antenna is normally employed.

Its size and natural radiation resistance make it well matched to

Linx modules. The proper length for a straight 1/4-wave can be

easily determined using the formula below. It is also possible to

reduce the overall height of the antenna by using a helical

winding. This reduces the antenna’s bandwidth, but is a great

way to minimize the antenna’s physical size for compact

applications. This also means that the physical appearance is

not always an indicator of the antenna's frequency.

Linx offers a wide variety of specialized antenna styles and

variations. Many of these styles utilize helical elements to

reduce the overall antenna size while maintaining

reasonable performance. A helical antenna's bandwidth is

often quite narrow and the antenna can detune in proximity

to other objects, so care must be exercised in layout and

placement.

Whip Style

Loop Style

L =

234

Where:

L = length in feet of

quarter-wave length

F = operating frequency

in megahertz

Specialty Styles

A loop- or trace-style antenna is normally printed directly on a

product's PCB. This makes it the most cost-effective of antenna

styles. The element can be made self-resonant or externally

resonated with discrete components but its actual layout is usually

product specific. Despite the cost advantages, loop-style antennas

are generally inefficient and useful only for short-range

applications. They are also very sensitive to changes in layout and

PCB dielectric, which can cause consistency issues during

production. In addition, printed styles are difficult to engineer,

requiring the use of expensive equipment including a network

analyzer. An improperly designed loop will have a high SWR at the

desired frequency, which can cause instability in the RF stage.

Linx offers low-cost planar and chip antennas that mount directly

to a product's PCB. These tiny antennas do not require testing and

provide excellent performance in light of their small size. They

offer a preferable alternative to the often-problematic "printed"

antenna.

COMMON ANTENNA STYLES

There are literally hundreds of antenna styles and variations that can be

employed with Linx RF modules. Following is a brief discussion of the styles

most commonly utilized. Additional antenna information can be found in Linx

application notes #00100, #00140, and #00500. Linx offers a broad line of

antennas and connectors that offer outstanding performance for low cost.