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Narrowband Transition

Railroads are mandated along with public safety to move to "narrow band" channel spacing by 2013. The FCC also recommends moving to 6.25 channel spacing on or near the year 2018. The Association of American Railroads (AAR) has come out in support of moving from the current 25 kHz channel spacing to 6.25 kHz "Very Narrow Band" (VNB).

Although there is no immediate requirement for users to move to VNB, the Association of American Railroads, after evaluating their long term requirements, and current scarcity of frequencies has recommended to their members to bypass an interim upgrade from 25 kHz to 12.5 kHz, but to move directly to 6.25 kHz.

In a prepared statement, the AAR announced that for interoperability, the Wireless Communications Committee recommends that any railroad purchasing VHF tri-mode radios for use in the 160 MHz band should specify NXDN compliance for 6.25 kHz VNB operation.