SageData supplies the products and services you need to automate data collection and processing, providing you with greater productivity, data accuracy, and insight into the operation of your business.
In this section we describe how to choose the barcode and RFID tags to use with our systems. We also supply software, scanning hardware, system design and configuration, and pre-printed labels .
On this page we cover
Barcode label material, symbology and common application errors
RFID tags and selection criteria
Barcode Labels
1 - Introduction
A barcode is a label which contains some of its information in barcode format. In most cases, the content of the barcode is also printed in human readable format
Barcodes allow the user to quickly and accurately record information that is unique to a particular item. When paired with SageData software that allows user input of real time data (location, status, user ID, etc), the scope, accuracy and productivity of many data collection tasks is greatly increased and with it the quality of the business decisions based on that data.
The scanners used for these differing tasks vary depending on the environment, the quantity of information to be collected, and the rate at which it must be collected
2 - Materials & Security
Barcode labels can be printed on a variety of materials including paper, polyester, fabric and aluminium.
Labels can be printed on tamper resistant materials, which make it impossible to remove a label and place it on a different item. We offer pre-printed labels with or without serialized numbering
Click here to request a quotation for pre-printed barcode labels or blank label stock.
3 - Symbologies
There are over 70 different barcode symbologies available but only a few are widely used today. Think of the different barcode symbologies as a different font that you would use on your printer. Options include:
- Code 128 - A modern all purpose code
- Code 39 - A solid and robust code, similar to code 128, still in common use.
- UPC - The code we find on our groceries. Not recommended for other industrial uses
- EAN the European version of UPC.
How to choose the best barcode symbology for your application? Contact SageData directly to find out which would be best for your application.
4 - Common Errors.
There are a number of errors made in the implementation of barcodes. The most common are:
Quiet Zone
All bar codes require a "quiet zone" of white space to prevent the reader seeing a wide black bar at the beginning and end of the barcode. This can be difficult to diagnose, as the labels will scan properly when on the roll or if placed on a white surface.
A black and white problem
Barcodes are intended to be printed as black stripes on a white background. Any other combination is operating outside the specification and the success of a scan is down to luck. We recommend that if colour is required for identification, it be applied as a strip above or below the barcode.
Squeezing too hard
A fairly common problem occurs as the numbers in a system increase and the barcode gets longer, which may mean less quiet zone (see above). Alternately, as the bars (and spaces between them) become thinner, the barcode becomes more difficult to read. Solution - use a different symbology - or a longer label!
For more information about barcodes, visit our learning centre
RFID Tags
1 - Introduction
RFID - Radio Frequency Identification is a technique which uses a radio signal to communicate with a small tag, and, by extension, the item to which that tag is attached. These are commonly small items, goods in transit, fixed assets or file folders, but use can extend up to larger items, vehicles and agricultural or construction machinery
2 - Considerations in choosing RFID tags
RFID tags can be grouped by a number of characteristics, specifically: active or passive tags, circular or linear antenna, operating frequency.
2.1 Active or Passive RFID Tags
Passive tags have no internal energy source. They have an antennae or receiving coil, which collects and stores energy transmitted by the reader. The tag then emits a short burst of energy, encoded with the critical information it is communicating. Passive tags only transmit when they have been energised by a reader.
Passive tags tend to be cheaper and smaller, and their life is only limited by the reliability of their components. They can be expected to function for decades. The range at which the tags can be read depends on their frequency of operation, and the power of the reader. Range can vary from less than a centimeter to several meters.
The ability to read a tag is affected greatly by the reader. Readers can be fixed, or integrated with a portable handheld computer. In mobile applications some readers are still relatively bulky and large, with the transmitting and receiving antennae being three or four inches high and just as wide. Others are smaller, sometimes with a reduced read range as a consequence.
Active tags get their power from a small internal battery.
They can be read at greater distances, but they tend to be slightly larger and more expensive. The life of an active tag is limited by the life of the battery, which generally cannot be replaced. The life of an active tag is of the order of several years, though this can be modified as the tag is set up, with speed of response being traded for battery life. From the time of manufacture, until the battery expires, these tags regularly transmit a small message which uniquely identifies them whether in range of a reader or not. A typical cycle would be once per second.
2.2 Antennae types - circular or linear.
The two different formats of antenna result in different reading capabilities. The linear antenna can give a longer read range, but requires a specific alignment for the tag to be read. If the reader is held "on its side", then range is dramatically diminished. For a circular antenna, the orientation of the reader with respect to the tag does not affect read range.
As an example, a typical mobile circular antennae may have a read range of six feet, regardless of orientation, compared to a similar linear reader, which might have a read range of twelve feet when properly aligned, but only twelve inches when either the tag or the reader is rotated through ninety degrees.
2.3 Frequency Range - passive tags
Tags can today be broken down by frequency into three categories. Each has specific benefits and drawbacks, and choosing the "best" tag depends very much on the application.
Low Frequency tags operate in the range 125 KHz. These were the first tags to be developed, and are frequently used in animal tracking. Their physical design makes them thicker and more expensive to manufacture. Range is of the order of an inch or so.
High Frequency RFID tags operate in the range 10-15 MHz. These are frequently used for access controls. These tags are thinner and typically occupy a similar surface area to a credit card, though smaller button versions are available which can be sewn into the hem of a garment. Read range is typically up to twelve inches.
Ultra High Frequency tags operate in two bands, around 900 MHz and 2.4 GHz. These are the most recently developed tag, and are used in unit tracking and supply chain applications. These tags use a simple design, though the antennae still needs to be a few inches long to give a reasonable read reliability. Often, the tags are encapsulated, and may be artificially thick, to enable the tag to be mounted on a metal surface. Read ranges can be up to twenty feet of more, but the tags are more affected by metal or liquid.
We can provide a variety of tags in LF, HF or UHF variants, with different package options available in each category. RFID tags must be carefully selected for each specific application.
If you would like further and more detailed information on your specific application, one of our experts will be pleased to help you. Please feel free to call or email with your questions.
For more information about RFID tags, visit our learning centre
For more information...
SageData is based in Ottawa, Ontario, Canada.
We design systems around RFID, Barcodes and Handheld computers.
For further information, contact Doreen Wallace or Keith Jackson.
To reach us by email, click here.
To reach us by phone from Ottawa, dial 613 225 4404
To reach us by phone from outside Ottawa, dial 1-888-838-1067
(c) SageData . Ottawa . Ontario . Canada
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