What type of radio signals are designed to be jam resistant?

Frequency-hopping radios are designed to be jam resistant due to their unique method of transmission. Instead of transmitting on a single frequency, these radios rapidly change their transmission frequency, hopping between different frequencies in a predetermined sequence. This technique makes it difficult for a jammer to disrupt communications, as the jamming signal would need to cover a wide range of frequencies and be synchronized with the hopping sequence to effectively interfere.

This method enhances the robustness of the communication system against interference and jamming since if a particular frequency is being targeted by interference, the communication can continue seamlessly on other frequencies. It's an effective approach to maintain transmission integrity in environments where electronic warfare tactics, such as jamming, may be employed.