1)Frequency and regulations

Frequency	125K 13.4Khz	13.45Mhz	860-960Mhz	2.4Ghz
Reading Range	Short (few cm to cms)	Within 1m	1m-30meters	10-200meters
Works with Metal	Yes	Yes	No	Yes
Works with Liquids	Yes	Yes	No	Yes

 

In general, low-frequency and high-frequency tags tags are read from within 1 meter ,and UHF tags reading range can be 1meters to 30 meters .2.4G active tag can be 50m to 200 m max.6 Factor that affect UHF reading range

And there are different regulations and limits on tags in different countries, which will affect read range.  In Europe, the operating frequency is lower, and they are limited to using less power than in the U.S., so the range for the same tag might be reduced in another country.

 

2)Tag size and type

 

As a general rule, small tags will have shorter read ranges, and large tags will have longer read ranges as RFID tags contain antennas and because larger antennas will broadcast farther than smaller antennas,There are hundreds of different types of sizes and options (label,anti-metal tag,retail tag,laundry tag,windshield tag/animal ear tag ect). Different type and size for different application to suit different installation environment.

The larger the tag you choose, the larger the antenna will be, meaning it will have a greater read range than a small tag.  There are some exceptions to this rule, especially for tags designed to mount on metal assets.   These tags can be small and still achieve a large read range because they use metal to improve their performance.  Often customers prefer to find the smallest available tag, with the assumption that all tags have the same read range.  For example.animal ear tag can be optional as Pigeon Foot Ring ,sheep cow ear tag, Animal Microchip.frequency can be  125Khz and 860-960Mhz ,and each tag (ear tag) can be different size and even customized for a bigger reading range or installation limited.

3）Target object

All RFID tags are affected by the materials around them, but the degree to which they are affected depends on the type of tag. Straight UHF tags are affected most as metal reflection of RF energy and water absorption of RF energy.These tags have no on board power source, so they rely on energy that they harvest from the reader. If they are close to conductive material, the transfer of power from the reader is disrupted, and the communication with the RFID chip is lost. Conductive materials in this case include metal and water, particularly salty water. The human body contains lots of salty water, so a passive RFID chip held close to the body (or in a pocket or wallet) may be difficult to read.

 

4)Reader and antenna

Reader &antenna tape affect RFID tag reading range. For UHF tags, power is provided by the reader, and the trade off between range, battery life and antenna size for a mobile reader means that read range is reduced. A typical working range for a mobile handheld reader is up to 6meters. again, depending on tag configuration. A fixed  reader has more power available, and a larger antenna. Read range in normal practical conditions can be up to 30 meters.

5)Environmental Factors:

Different environmental conditions can affect the performance of RFID tag. Water, metal, florescent lighting, large machinery, and competing frequencies (other radio waves) may adversely affect UHF RFID read ranges. The best way to maximize read range is to note the various possible forms of interference and attempt to mitigate that interference by testing, making changes to your system, and retesting.Really suggest do field test again and again before bulk use.

 

Weather conditions can often be a variable on the read range.  For instance, some target object is exposed to extremes of hot or cold temperatures, humidity, and rain.  All these unpredictable conditions can cause variations in read range.

Reading range is one of the main factor for us to choose the right tag,if you want learn more about how to choose the right RFID tag,follow us or contact with us