Bob Scher, CEO, Dynasys Technologies Inc.
Clearwater, Florida

The use of RFID is very quickly becoming a popular technology choice for automatic data collection. It allows for a fast, reliable solution in industries where bar code technology could not previously provide a satisfactory result. With RFID technology moving forward at such a rapid rate, there are more and more vendors claiming to be experts in the field, leaving the end user with the difficult choice of selecting the optimum hardware and a suitably qualified solution provider.

Choosing the Right Technology

The first and very important part of choosing your solution is to correctly select the right technology.

Some things to consider:

• Choosing the right frequency system

RFID transponder systems commonly have operating frequencies as low as 60 kHz and as high as 5.8Ghz a factor of nearly one million times. It is therefore necessary to understand why there is such frequency diversity so that the correct operating frequency system is chosen for the operating conditions of the desired application. Electromagnetic propagation, by which energy is transferred radio frequencies, has a magnetic field mode and an electric field mode. The magnetic mode is generally preferred for a system operating below 100 MHz this allows the use of antenna systems that compromise of small coils.

The electric field mode is preferred for frequencies above 100 MHz, which typically utilize much smaller antennas. Both systems have their various advantages and disadvantages. In general the lower frequency magnetic coupled systems can withstand a more metal and moisture interference than the higher frequency systems, however ranges of more than 1.5 meters are not easily achieved using passive tags. Also as a general rule, the larger the antenna (tag coil) and reader antenna (reader coil) the better the read range.

Although the higher frequency tags can offer greater read range these systems typically utilize powered tags (Active) to achieve the extended range. The downside of using a powered tag is that it has a limited life span due to the limited battery life.

Passive tags in the higher frequency electric field ranges can normally demonstrate impressive read ranges, but can be very directional and susceptible to interference from moisture and metal presence.

• Choosing the right tag

With the above in mind one should realistically identify the read range actually required. This will help you to select products that operate at the suitable frequency, whether active or passive. In most cases the cost of the tag is an important consideration. Although active tags provide impressive read ranges, they usually come at a much higher price and are normally larger in size when compared to passive tags. Most production line and asset management applications can utilize passive tags, due to their relatively low cost and smaller sizes.


These passive tags are available in many different forms and materials. They are commonly available as label tags, transponder disks and key fobs.
Manufactures have adopted the 125Khz - 134 kHz band as their operating frequency for their passive systems. These tags are relatively inexpensive and offer a good all around performance for many applications.

Once you have identified whether you need an active tag or a passive tag you need to consider the following:

Should you choose ACTIVE tags you need to identify the required life span of the tag. Many active tags have a limited life span of a few years and once expired the tag must be replaced. However, active tags are also available with external power supplies giving them an extended life span.

Should you choose PASSIVE tags you need to consider how robust the tags need to be. This will affect the size, material and cost of the tag. Generally, the greater the read range required the large the physical size of the passive tag.

• Choosing the right reader

The most important aspect in choosing the proper reader is the overall reading distance required. When using 125 - 134 kHz passive systems, the greater the read range required the higher the power of the reader required and the larger the antenna (scanning coil) required. When dealing with active tags, the choice of antenna system becomes most critical. This has an affect on both the size and cost of the reader.

In many applications a hand held terminal or portable reader is required. These are typically used for reading passive tags. The readers can be peripheral adapters directly attached to hand held computers. Other hand held solutions require a tethered connection to the hand held computer or host PC, making them better suited to fixed reading points or desk top applications.

• Choosing the installer

This is a vitally important part of a successful RFID solution. It is critical that the installer is familiar with RFID technology and the products that are to be installed. High quality readers, if installed or positioned incorrectly, can produce disappointing results.

Choosing Your RFID Component Manufacturer

A number of RFID manufacturers have become well recognized throughout the world. The technology was originally pioneered by these manufacturers to provide reliable and robust proximity card solutions, now widely accepted and used extensively for secure access control applications. A number of these early pioneers continued to develop the technology, producing readers with extended and faster read and write capabilities. With the increase in consumer demand for RFID systems, the cost of the readers and the tags has seen some dramatic reductions.

Each RFID manufacturer has developed its own product range offering specific characteristics such as read ranges and data transmission protocol. A suitably qualified manufacturer should be able to offer a diversity of systems; each developed to cater for a specific requirement.

The diversity of systems offered is an important indicator that the manufacturer is willing to work closely with the consumer in order to customize a solution to meet the specific requirements.

Choosing the Right Distributor or System Integrator

A good starting point is to find a company that has a sound track record in the automatic identification market.

RFID technology operates on radio frequency signals and for this reason, changes in the environment can alter its performance significantly. It is important that the integrator understands these complex technical aspects and is able to provide professional advice to the end user.

The System Integrator should already well known as an engineering solution provider. The Integrator must ensure that the prospective user understands the benefits and limitations of certain RFID products and be able to supply the optimum equipment for the specific application. In many instances it is important for the success of the project that the supplier is able to work with the manufacturers to supply customized tags and antennas.

Choosing the Right Products

It is important that the supplier selected is able to offer you all the available options, including active and passive tagging systems. By selecting products from a supplier that offers a diverse range it will enable you to maintain an RFID standard throughout your operation. This will ensure that systems are expandable and that the tags used will be read by all readers whether they are intended for access control or asset management purposes.

Make certain that your supplier provides you with information on the various frequencies at which tags can operate. The different frequencies display different characteristics in a variety of environments and can ultimately affect the success of the solution. In an application where the environment is constantly changing, such as on a production line where conveyers are moving products, it is vitally important that the readers have the ability to automatically adjust their tuned frequency to always give the best possible read range.

The right combination of product range, knowledge, system integration and technical support will ensure that your transition into the exciting and rapidly developing world of RFID will be a painless and successful venture.

Please click on the following link to download a PDF file of this document: Making the Right Choices