Ξ July 26th, 2011 | → Comments Off on Radio Frequency Identification is Multiple Radio Frequency Technologies not just one! | ∇ Active RTLS, HF High Frequency, LF Low Frequency, RFID News, UHF Ultra High Frequency |
We are constantly amazed at the questions that prospective users ask when they visit our web site. While RFID has been around for more than 5 decades it seems many people still have the opinion that RFID is a single technology that uses multiple Radio Frequencies. Supposedly these different frequencies are used based on the needed read distance between the reader and tag and the material that the RFID tag is attached to.
Wow – would that be a lovely world to be in – easy, fast, simple.
RFID technology is far more complex that just multiple Radio Frequencies. There are the standard ISM (Industrial, Scientific and Medical) band frequencies that were reserved internationally for purposes other than communications. Generally these ISM frequencies do not require licensing but are usually locally regulated in the bandwidth and power that can be used and any devices used in these frequencies must accept any interference generated in this ISM band. Outside of the ISM band there are a number of frequencies that may or may not require local licenses to operate.
If we just concentrate only on the ISM band and only on the larger well known RFID frequencies we have the following wavebands – 125~150 kHz ( usually broken down to 125 kHz and 134.2 kHz), 13.56 MHz, 433 MHz, 860~960 MHz, 2.4 GHz, and finally 5.8 GHz. So we have at least 7 wave bands that can and are being used for RFID applications. Reality is there are 14 bands used – http://www.skyrfid.com/RFID_Frequencies.php – in this blog we are just looking at the commonly known bands.
In addition to the commonly used 7 wave bands; we have Passive and Active technologies that govern how the tag and readers inter-operate:
Passive Technology – where the non powered equipped RFID tag is dormant until excited by an RFID Interrogator (RFID Reader);
Semi Passive/Semi Active Technology where the tag contains a battery or some other power boosting device so that when excited by a Reader the tag contents can be read;
Active Tag and Reader Technology where the Tag has a power source and can talk/beacon without a Reader exciting it and the Reader can talk to the Tag and change its contents or communication methods;
And finally Active Tag and Passive Reader Technology where the Tag has a power source and can talk/beacon without a Reader exciting it and the Reader only listens for tags.
So now we see we have 7 wave bands and 4 different technologies that can be utilized within the wave band.
Within each of these technologies we also have the following Tag Read and Write Characteristics:
125 kHz – Low Frequency – Usually read only, but can be read and write – usually limited to 10 hexadecimal characters, usually short range almost touch – but with the right Reader and Tag combination can read over 1.5 meters!
134.2 kHz – Low Frequency – Also usually read only and 15 hexadecimal characters, but many of the tags can be read and write and like the 125 kHz was usually short read range – under 50 cm, but with the right tag and reader combination can easily go over 2 meters.
13.56 MHz – High Frequency – the biggest usage of all bands – and the most complex, no security, some security, DES security, EAS security, all kinds of flavors, mostly read write, several ISO standards, varying read distances, varying user memory sizes, and constantly evolving. For user memory we can go from 64 bits to over 4K on standard I/C’s. The new Smart Technology can have hundreds of kilobytes of storage and even its own operating system on the tag!
433 MHz – Ultra High Frequency – older band, was primarily Military but is now providing the longest read range of all bands – commonly read only and limited memory.
860 ~ 960 MHz – Ultra High Frequency – newest band – now known as the EPC Gen 2 band – never fully used in any country but parts of the band are used in different countries so that the same tag can be read all over the world – originally designed for end to end supply chain management, now being used for a huge number of passive tag applications. This EPC Gen 2 has a large number of flavors and variations built in to accommodate global acceptance –http://www.skyrfid.com/RFID_Gen_2_What_is_it.php
Within the 860 ~ 960 MHz band there is another band 916 MHz – not well known yet but growing in application usage. Commonly this band is Active tag Passive Reader with a shorter read distance than the huge 433 MHz read distance but far larger than the 2.4 GHz and 5.8 GHz ranges.
2.4 GHz – Super High Frequency – also known as the WiFi band – can be WiFi enabled or can be proprietary, but is usually active tag and active reader with a range of up to 100 meters, sometimes more.
5.8 GHz – Super High Frequency very similar band to our new wireless phones! shorter read distance than the 2,4 GHz band but we can amplify the read range with more power and larger antennas.
For more information on the passive tag Read Write and Memory capabilities – http://www.skyrfid.com/RFID_Tag__IC_Chips.php
So now we know there are at least 7 frequencies and 4 reader/tag technologies that can be used for RFID applications. Next blog we will look at each of the 7 ISM bands and try to understand their basic characteristics.
About SkyRFID Inc.
SkyRFID is a privately held Canadian company specializing in Automated Data Collection (ADC) solutions that use Radio Frequency Identification (RFID) technology. SkyRFID has over 20 years of experience in ADC and provides customers with everything from a single consulting engagement to a complete turnkey global solution. SkyRFID personnel have implemented solutions in all of the Americas and many other countries with great success. SkyRFID provides solutions in Low Frequency (LF), High Frequency (HF), Ultra High Frequency (UHF) and Microwave (SHF) RFID technologies and has considerable expertise in Animal Management,Asset Management, Access Control, Document Management, Library Systems, Field Service, Manufacturing, Parking Management, Supply Chain, Warehousing and Distribution, Event Management, Fleet Maintenance, and Custom Tags.
SkyRFID excels at Weapons Management and Tracking and Electronic Vehicle Identification and Management.
For more information contact SkyRFID Inc. at +1 647-476-3265
Web Site: www.skyrfid.com