The NXDN (Next Generation Digital Narrowband) common air interface protocol, which was developed jointly by ICOM and Kenwood, uses Frequency Division Multiple Access (FDMA), employing a 4-level FSK modulation scheme.
Kenwood's brand for NXDN equipment is "NEXEDGE", while Icom's brand for NXDN equipment is "IDAS", or Icom Digital Advanced System.
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