Linx offers radio modules in several frequency bands targeted for different applications and different geographical regions.
315MHz is a common frequency for RKE and garage door systems. As a result, this frequency is somewhat crowded, increasing the chances for interference. Also, the antenna size gets larger, or the efficiency decreases for the same size antenna.
418MHz is a good frequency to use in the US as it is not very crowded. This gives the least likely chance for interference and therefore the best performance. This is the standard recommended frequency for North America.
433.92MHz is almost a global frequency, primarily due to automotive key fobs. This makes it a good frequency for products that will be marketed in multiple countries since only one product needs to be built. However, this makes the frequency popular and more crowded than 418MHz, increasing the chance for interference.
863 – 870MHz is an unlicensed band in Europe. The band is subdivided for different applications, and has restrictions on the amount of transmitter on time per hour based on which sub-band is being used. The band has only 2MHz to support many applications, so it has become somewhat crowded.
902 – 928MHz is more versatile than the 260 – 470MHz band in the US because the FCC has only specified the output power and harmonic levels. There are no restrictions on the type or duration of data that can be sent. This gives the design engineer a great deal of freedom in the possible applications, but also results in the band being more crowded. A disadvantage for cost-sensitive applications is that 900MHz modules are typically more expensive due to the more complex filtering and modulation required for link reliability at these higher frequencies.
2400 – 2483.5MHz is a true global frequency. Almost all developed nations have adopted the same regulations and requirements for this band. This was driven by applications such as Wi-Fi and Bluetooth but been adopted by many more applications. This means that it is possible to make one product and sell it into many countries, though the product does still need to get certified in each country or region. This has made the band extremely popular and extremely crowded. In addition, the range of these systems is much shorter and the signal penetration through walls and obstructions is much worse at these frequencies than at lower ones.
5725 – 5875MHz has not been adopted by many applications outside of Wi-Fi. This band is generally covered under the same rules as the 2400MHz band. There are not many products in this band. Currently, Linx does not offer any radios in these frequencies.
Review AN-00125: Considerations for Operation within the 260 – 470MHz Band, AN-00126: Considerations for Operation within the 902 – 928MHz Band, AN-00128: Data and bidirectional Transmissions under Part 15.231, FCC Resource Document and FCC Title 47 for more information. You may obtain a hard copy of FCC Title 47 from your local government bookstore or from the Government Printing Office in Washington.