DSMX

DSMX is a radio control link protocol used by Spektrum. It is an improvement over the older protocol DSM2, with which DSMX is backwards compatible. DSMX was released in 2011.

DSMX uses both frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS) techniques. It hops over 23 channels in 2.4GHz band. Frequency shift pattern is calculated using a globally unique ID stored in the transmitter.

The main advantage of DSMX compared to DSM2 is higher resistance to noise in the 2.4GHz band (e.g., from WiFi, microwaves, smart home devices or radio controllers). According to Spektrum, DSMX transmitters can operate well in the vicinity of 100 other DSMX transmitters, allowing it to be used in large RC gatherings. Nevertheless, DSMX is know to have poorer resiliency compared to more modern RC links.

DSMX receivers communicate to the flight controller using SPEKTRUM2048 protocol.