Automatic Vehicle Monitoring (AVM)
From Signal Identification Wiki
 | |
|---|---|
| Frequencies | 517.875 MHz,507.225 MHz |
| Frequency Range | 507.225 MHz - 517.875 MHz |
| Mode | NFM |
| Modulation | FFSK |
| ACF | — |
| Emission Designator | — |
| Bandwidth | 7.5 kHz |
| Location | Melbourne, Australia |
| Short Description | Proprietary FFSK data network used for public transport telemetry. |
| I/Q Raw Recording | Download file |
| Audio Sample | |
The Automatic Vehicle Monitoring (AVM) system was implemented on Melbourne's public Bus and Tram network in the 1980s. It is primarily used to track and control vehicles, as well as providing route information and location data. Since 2009 the system feeds the PIDs at tram stops and stations, as well as the TramTracker app for mobile devices.
Samples[edit]
- Uplink
This sample below is the uplink channel. Note the rapid FFSKFast Frequency-Shift Keying data bursts from multiple mobile units:
- Voice Transmissions
Data is also transmitted at the end of each mobile voice transmission:
Tram driver communication:
Short conversation between driver and dispatch:
