Nexedge (NXDN) Systems

Conventional IP networks link digital conventional repeaters into one system for wide area coverage or to provide coverage fill-in extensions. As users roam through the network, subscriber units use beacon signals to select the best repeater. Subscriber zones can be programmed for Channel Select for traditional conventional operation, or Automatic Site Roam, which allows subscriber units to scan for site beacon signals to lock onto for network calls. Receiver Voting systems extend the portable talk-in range of a conventional repeater by utilizing a constellation of satellite receivers linked to the repeater site. Based on radio signal strength data (RSSI) sent via IP link, the repeater site selects the receiver site with the best audio quality for re-transmission. For a large organization, multiple repeaters can be connected to an IP network. This inexpensive solution allows voice and data to be exchanged between sites.

NXDN Type-D Trunking is the FB6*-based digital LTR protocol specified by the NXDN Forum. Unlike Type-C trunking, there is no dedicated control channel: trunking is under the control of the home repeater assigned to each radio. And like LTR, there is no registration. This cost-effective solution thus offers spectrum efficiency and simplicity.

FCC Station Class Code

NXDN Type-C Trunking is the FB8*-based full-featured digital protocol specified by the NXDN Forum and used for NEXEDGE since 2007. Type-C is otherwise known as centralized trunking; this is because, unlike Type-D, trunking is controlled centrally using a dedicated control channel that is continuously transmitting and receiving. As with MPT 1327, registration is required.
P25 Phase 1 (FDMA scheme) can also be used in a robust and reliable trunked configuration for larger organizations. Since the channels are assigned automatically, this provides greater capacity.
P25 Phase 2 (two-slot TDMA scheme) requires only 6.25 kHz of bandwidth and thus offers higher spectrum efficiency.

FCC Station Class Code

NEXEDGE Generation 2 (Gen2) offers a quantum leap in network size: the maximum number of sites than can be connected has increased from 48 to 1,000, representing virtually unlimited scalability. At the same time, it provides full compatibility with current equipment. For enterprises looking to create large-scale digital trunked networks, Gen2 has the features, capabilities and performance to satisfy all their requirements.