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multi dimensional multiple access (MDMA)

MDMA modulation (Multi Dimensional Multiple Access) combines the advantages of the classic modulation methods ofamplitudemodulation ( AM), frequency modulation( FM) and phase modulation. This adaptation of the modulation methods is suitable for WLANs with medium and high transmission rates and is characterized by extremely low power consumption. MDMA can be adapted in its quality to the services and provides a different quality of service to a voice transmission than to a money transaction.

MDMA uses two basic signals for processing and symbol transmission: The Sync pulse for processing in baseband techniques and the Chirp pulse for radio transmission. The sync pulse is a narrow short duration pulse with the shortest pulse duration relative to the available bandwidth. The product of pulse duration and bandwidth is thus "1". The chirp pulse is a burst whose frequency changes linearly from a lower frequency to an upper frequency in the specified time. It fills the available bandwidth in a specified time. Both pulses, the sync pulse and the chirp pulse, occupy the same bandwidth and can be easily transformed against each other using a surface wave filter. The combination of both pulses form the basic principle of MDMA modulation.

Principle of MDMA modulation

Principle of MDMA modulation

MDMA, which is used in nanoNET, is equally suitable for indoor and outdoor applications. Data rates are well over 100 Mbit/s at distances of 100 m outdoors and 10 m indoors. At 2 Mbit/s, the distances increase to 800 m and 80 m respectively.

Particularly noteworthy is the low interference from other devices transmitting in the ISM band and the resulting possible reduction in transmission power and battery life.

Informations:
Englisch: multi dimensional multiple access - MDMA
Updated at: 19.04.2013
#Words: 262
Links: modulation, access manager (AM), frequency modulation (FM), fault management (FM), phase modulation (PM)
Translations: DE
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