Choose Right Frequency for Remote Control Transmitter Project – 315MHz VS 433MHz

For newly developed remote control transmitter or receiver project, we always recommend our customer to use 433.92Mhz frequency or known as 433Mhz or 434Mhz in some places, as there are many advantages for choosing this frequency.

When starting a remote control transmitter and receiver project, most times customer won’t ask which frequency to use, as what they want is having something that works out of box, frequency doesn’t matter in this case, but if customer has some concerns, and want to choose the right frequency, here are reasons.

First, choosing 433.92Mhz is more suitable for international marketing.

Customer in Europe will no doubt choose 433Mhz since is it required in EU / CE R&TTE regulations, while in the USA, customer usually can choose from 260 to 470Mhz freely, as they’re all approved frequencies in FCC ID regulation, but due to the cost and other concerns, there are simply two options that chosen most by customers, that is 315Mhz or 433Mhz.

So 315Mhz is not allowed in Europe, while both 315Mhz and 433Mhz can be allowed in USA, so to be more international, we would recommend our customers choose 433Mhz because it is simply a worldwide frequency that can be used everywhere.

Second, choosing 433.92Mhz has operating distance advantage.

As a customer, or manufacturer, in most circumstances, it is desired to achieve the maximum range by transmitting maximum output power allowed by regulatory agency, to make device operate in longer distance, or can be more stable in tough situations, thus higher transmitted power is good in most circumstances, while take FCC ID for example, the allowed transmitting power within 260 to 470Mhz range varies on different frequency, for example, the allowed power rating at 315Mhz is around 5dB lower than 433Mhz, thus although most receivers can have a 2dB sensitivity advantage at 315Mhz over 433Mhz, we will suffer from at least 3dB loss when choosing 315Mhz frequency, which simply means we have to use better receiver, or has shorter operating distance when using same receiver module.

In conclusion, if there is no other aspects to consider, such as specific requirement in given operating environment, then choose 433.92Mhz is the better choice, as it can not only reduce the overall cost, but also increase the average performance.