A DOS program which acts as a sound spectrum 'analyzer' also reveals its data rate in the 9600 bps range. The image the program (slicer.exe) produces is clearly different from the slower data rates used by Moto I/II systems.
A Google search on IWN (Integrated Wireless shows some interesting stories --
http://iwce-mrt.com/ar/radio_feds_accelerate_network/
Here's a quote from another -- In an effort to improve public safety interoperability, all new or upgraded radio systems and new radio equipment should be compatible with a suite of standards called ANSI/TIA/EIA-102 Phase I (Project 25). These standards have been developed to allow for backward compatibility with existing digital and analog systems and provide for interoperability in future systems. The FCC has chosen the Project 25 suite of standards for voice and low-moderate speed data interoperability in the new nationwide 700 MHZ frequency band and the Integrated Wireless Network (IWN) of the U.S. Justice and Treasury Departments has chosen the Project 25 suite of standards for their new radio equipment. In an effort to realize improved interoperability, all radios purchased under this grant should be APCO 25 compliant." And, try
http://www.ojp.usdoj.gov/odp/docs/ODPApplication.pdf
One Dep't of Justice offical said the key architectural elements of IWN are:
*Association of Public Safety Communications Officials (APCO) Project 25 compliant
*Primarily VHF (UHF used in prisons and selected seaports and airports)
Trunked radio
*Internet Protocol (IP) based integrated voice and data infrastructure
*Over-the-air rekeying
* Commercial services to augment Government-owned land mobile radio