MSSR "Avrora"
1. The implementation of extended surveillance by using ADS-B is the promising way to increase the Air Traffic Control (ATC) systems efficiency.
At present, the extended surveillance realization provides for the implementation of mode S SSR and ADS-B systems on the base of:
- listening of extended squitters transmissions;
- mode 4 VDL;
- universal transceiver (UAT).
Although the realization of extended surveillance using mode S SSR is the most usual way, it is likely to find its application only in the areas of high air traffic intensity due to economic reasons.
In the other areas the standard MSSRs allowing the ATC system to get air traffic situation information independently of airborne navigation systems and their data sources condition are used and are likely to be used in future.
MSSR upgrading by adding the capability to receive the ADS-B information allows to realize the extended surveillance functions with minimum expenses and also to maintain the surveillance independence using ADS-B data validity monitoring.
2. The block diagram of the MSSR-JAC modification for receiving the ADS-B data, transmitted in extended squitters via the mode 4 VDL channels (optional) is presented in Fig 1. The supplementary equipment is shown in blue and grey. Four fixed antennas with 90° beamwidth, located at the antenna module are used for the extended squitters reception. A four-channel receiver provides separate receiving and decoding of squitters for each of four azimuth sectors. The information on the same target from the different sources is combined on the basis of the respective 3D tracks identity analysis.
Fig.1 Modified MSSR-JAC block diagram.
3. Main performance specifications of the modified MSSR-JAC are given in the following table:
Parameter name
| RBS | UVD | ADS |
En-route/
terminal | En-route/
terminal | Squitter |
| Coverage area | | |
|
| Max range, km | 465/250 | 465/250 | 400 |
| Min range, km | 1 | 1 | 0.25 |
| Altitude, km | 20/12 | 20/12 | 20/12 |
| Elevation angle, deg | 0.3/45 | 0.3/45 | 0.3/45 |
| Number of targets | | |
|
| Per scan |  200/400 | 200 |
| Modes | A/C | N/H | Passive reception |
| | | | |
| Accuracy (RMS) | | |
|
| Azimuth, deg | 0.8 | 0.12 | |
| Range, m | 20 | 20 | |
| Latitude, min | | | GPS |
| Longitude, min | | | GPS |
| Altitude discrete, m | 30 | 10 | GPS |
| | | | |
| Resolution | | |
|
| In azimuth, deg | 1 | 1.5 | GPS |
| By range, m | 100 | 400 | GPS |
| Detection probability | 0.98 | 0.98 | 0.95 |
| | | | |
| Scan rate, sec | 20..10/6..4 | 20..10/6..4 | 0.5..5 |
| | | | |
| Extended surveillance data | No | No | Yes |
|
