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ACHIEVING A SUCCESSFUL RF IMPLEMENTATION

Adding an RF stage brings an exciting new

dimension to any product. It also means that

additional effort and commitment will be needed to

bring the product successfully to market. By utilizing

premade RF modules, such as the KH Series, the

design and approval process is greatly simplified. It

is still important, however, to have an objective view

of the steps necessary to ensure a successful RF

integration. Since the capabilities of each customer

vary widely, it is difficult to recommend one

particular design path, but most projects follow steps

similar to those shown at the right.

In reviewing this sample design path you may notice

that Linx offers a variety of services, such as

antenna design and FCC prequalification, that are

unusual for a high-volume component manufacturer.

These services, along with an exceptional level of

technical support, are offered because we recognize

that RF is a complex science requiring the highest

caliber of products and support. “Wireless Made

Simple” is more than just a motto, it’s our

commitment. By choosing Linx as your RF partner

and taking advantage of the resources we offer, you

will not only survive implementing RF, you may even find the process enjoyable.

HELPFUL APPLICATION NOTES FROM LINX

It is not the intention of this manual to address in depth many of the issues that

should be considered to ensure that the modules function correctly and deliver

the maximum possible performance. As you proceed with your design you may

wish to obtain one or more of the following application notes, which address in

depth key areas of RF design and application of Linx products. These

applications notes are available on-line at www.linxtechnologies.com or by

contacting the Linx literature department.

DECISION TO UTILIZE RF IS MADE

RESEARCH RF OPTIONS

LINX MODULE IS CHOSEN

ORDER EVALUATION KIT(S)

TEST MODULE(S) WITH

BASIC HOOKUP

INTERFACE TO CHOSEN

CIRCUIT AND DEBUG

CONSULT LINX REGARDING

ANTENNA OPTIONS AND DESIGN

LAY OUT BOARD

SEND PRODUCTION-READY

PROTOTYPE TO LINX

FOR EMC PRESCREENING

OPTIMIZE USING RF SUMMARY

GENERATED BY LINX

SEND TO PART 15

TEST FACILITY

RECEIVE FCC ID #

COMMENCE SELLING PRODUCT

TYPICAL STEPS FOR

IMPLEMENTING RF

00100

RF 101: Information For The RF Challenged

00125

Considerations For Operation In The 260MHz to 470MHz Band

00130

Modulation Techniques For Low-Cost RF Data Links

00140

The FCC Road: Part 15 From Concept To Approval

00150

Use And Design Of T-Attenuation Pads

00160

Considerations For Sending Data Over A Wireless Link

00300

Addressing Linx OEM Products

00500

Antennas: Design, Application, And Performance

NOTE #

LINX APPLICATION NOTE TITLE

LEGAL CONSIDERATIONS

When working with RF, a clear distinction must be made between what is technically

possible and what is legally acceptable in the country where operation is intended. Many

manufacturers have avoided incorporating RF into their products as a result of

uncertainty and even fear of the approval and certification process. Here at Linx our

desire is not only to expedite the design process, but also to assist you in achieving a

clear idea of what is involved in obtaining the necessary approvals to legally market your

completed product.

In the United States the approval process is actually quite straightforward. The

regulations governing RF devices and the enforcement of them are the responsibility of

the Federal Communications Commission (FCC). The regulations are contained in the

Code of Federal Regulations (CFR), Title 47. Title 47 is made up of numerous volumes,

however, all regulations applicable to this module are contained in volume 0-19. It is

strongly recommended that a copy be obtained from the Government Printing Office in

Washington, or from your local government bookstore. Excerpts of applicable sections

are included with Linx evaluation kits or may be obtained from the Linx Technologies web

site (www.linxtechnologies.com). In brief, these rules require that any device that

intentionally radiates RF energy be approved, that is, tested, for compliance and issued

a unique identification number. This is a relatively painless process. Linx offers full EMC

pre-compliance testing in our HP/Emco-equipped test center. Final compliance testing is

then performed by one of the many independent testing laboratories across the country.

Many labs can also provide other certifications that the product may require at the same

time, such as UL, CLASS A/B, etc. Once your completed product has passed, you will be

issued an ID number that is then clearly placed on each product manufactured.

Questions regarding interpretations of the Part 2 and Part 15 rules or measurement

procedures used to test intentional radiators, such as Linx RF modules, for compliance

with the Part 15 technical standards, should be addressed to:

Federal Communications Commission

Equipment Authorization Division

Customer Service Branch, MS 1300F2

7435 Oakland Mills Road

Columbia, MD 21046

Tel: (301) 725-1585 / Fax: (301) 344-2050 E-Mail: labinfo@fcc.gov

International approvals are slightly more complex, although many modules are designed

to allow all international standards to be met. If you are considering the export of your

product abroad, you should contact Linx Technologies to determine the specific suitability

of the module to your application.

All Linx modules are designed with the approval process in mind and thus much of the

frustration that is typically experienced with a discrete design is eliminated. Approval is

still dependent on many factors, such as the choice of antennas, correct use of the

frequency selected, and physical packaging. While some extra cost and design effort are

required to address these issues, the additional usefulness and profitability added to a

product by RF makes the effort more than worthwhile.

N

NO

OT

TE

E:: Linx RF modules are designed as component devices that require

external components to function. The modules are intended to allow for full Part

15 compliance, however, they are not approved by the FCC or any other agency

worldwide. The purchaser understands that approvals may be required prior to

the sale or operation of the device, and agrees to utilize the component in keeping

with all laws governing its use in the country of operation.