Spektrum DSM - Digital Spectrum Modulation

DSM Module Systems
The Only Choice for Aircraft and Surface Control

How It Works

DSM Technology operates in the internationally accepted, ultra high 2.4GHz Industry, Science, and Medical (ISM) frequency band. This positions the technology well out of the range of virtually all model-generated and conventional RC system interfaces. All the usual glitches that haunt conventional AM and FM aircraft systems are simply eliminated with DSM.

Every DSM transmitter is factory programmed with its own unique Global Unique Identifier (GUID). Once a DSM receiver is bound to a specific DSM transmitter, it will only recognize that signals radio or module. With over 4 billion possible GUID codes, it is virtually impossible for a DSM receiver to mistake a signal source from another transmitter or any type. And because the FCC regulations require all 2.4GHz ISM technology to incorporate collision avoidance technology, you will not have to worry about interference from sources like wireless routers, other spread spectrum users, or cordless devices.

Patented DuaLink Technology

All the Spektrum aircraft systems are built with DuaLink technology that ensures a superior RF link the pilot and their aircraft. When a DSM equipped aircraft transmitter is switched on, it scans for two free channels in the 2.4GHz band. When it finds them, the DSM aircraft receiver, which is "listening" for its transmitter's distinct GUID, will lock onto the two free and clear channels. By using two distinct 2.4GHz channels, DuaLink ensures that you will enjoy a solid connection and outstanding precision regardless the altitude of your aircraft or the amount of 2.4GHz noise in the environment.

The Direct Advantage of DSM

There are two primary types of 2.4GHz spread spectrum technology use in the RC industry. These are Frequency Hopping Spread Spectrum (FHSS) and Direct Sequence Spread Spectrum (DSSS). FHSS systems transmit a narrow band signal and rapidly jump from one frequency to the next, spending a few milliseconds on each frequency. DSSS systems transmit on a single selected frequency, but on a very wide band. Only a small portion of that band is used for specially encoded information. With Spektrum, this is done twice since the system allocates two channels with the DSSS function.

Because FHSS based systems are relatively easy and inexpensive to develop, this was the original technology Spektrum engineers started to develop. However, it was quickly discovered that FHSS had certain limitations that would prevent it from being the optimum solution for RC use. While more difficult and costly to develop, Spektrum chose to pursue a DSSS based solution. The result, a patented DSM technology used in all Spektrum's RC radio systems on the market today.

Other than solving critical response and re-link issues, DSM provides more processing gain for superior range too. And as many more Spektrum enthusiasts have been appearing at indoor flying events where wireless routers and other 2.4GHz RC systems are in use, they have quickly discovered yet another huge benefit. As the 2.4GHz noise floor rises by more 2.4GHz units being turned on, users do not experience any reduction in response time. The DSSS based technology keeps latency at an absolute minimum regardless of how busy the 2.4GHz environment becomes.