User's Manual

P25net Channel Controller Operations Manual
1-2
combining two or more P25net sites with a Radio Network Controller (RNC) and a Network
Location Register (NLR) through an IP based network, a multi site system can be created.
Figure 1-2 Typical P25net System
1.3 Analog Base Radio Requirements
The following are general considerations for radios suitable for P25net CC interface
requirements.
1.3.1 Duplex Operation
The radio must be capable of full duplex operation as a base station rather than a repeater. This
is necessary because the P25net CC must control the repeat function.
1.3.2 Unbalanced Wideband Audio
Unbalanced Tx and Rx wideband audio without pre-emphasis and de-emphasis is required to
pass the 0-3000Hz baseband necessary for P25 signals. DC coupling is preferred since it
provides the best low frequency response. The capability to turn off all filters is recommended.
“Balanced Line Audio” means that transformers are in the signal path and will limit low
frequency response.
1.3.3 PTT/Keyline
The P25net CC provides an open collector for grounding the radio PTT/Keyline to
transmit.
1.3.4 RSSI
The P25net CC uses the Receive Signal Strength Indicator (RSSI) signal in determining
validity of a received P25 signal.