Lateral Positional Offset Errors
Table 1.
Lateral positional offset errors caused by small inaccuracy in the data from the support vessels compass about the actual or true headings. Ranges in the table are listed in meters. The underlined areas in the table highlight lateral positional errors of approximately 5 meters or less. See notes below for assumed conditions.
|
Horz. Range
[meters]
|
0.5 Deg
|
1.0 Deg
|
2.0 Deg
|
3.0 Deg
|
5.0 Deg
|
|
|
|
|
|
|
|
|
150
|
1.3
|
2.6
|
5.2
|
7.9
|
13.1
|
|
300
|
2.6
|
5.2
|
10.5
|
15.7
|
26.1
|
|
500
|
4.4
|
8.7
|
17.4
|
26.2
|
43.6
|
|
750
|
6.5
|
3.1
|
26.2
|
39.3
|
65.4
|
|
1000
|
8.7
|
17.5
|
34.9
|
52.3
|
87.2
|
|
1500
|
13.1
|
26.2
|
52.3
|
78.5
|
130.7
|
|
2000
|
17.5
|
34.9
|
69.8
|
104.7
|
174.3
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Notes:
Correct speed of sound is used.
Correct hydrophone offsets are used.
Hydrophone motion is corrected in the IPS with data from a vertical referencing unit (VRU), as done with a BATS system.
The above omitted any DGPS induced errors.
Support vessels compass headings contains no bias and is with respect to true North
Table 2.
Maximum tracking range in meters for beacons with and without depth telemetry. Note that the listed values have be rounded down to the closes hundreds of meters for clarity. The values in the table below are based upon a beacons turn-around-time (TAT) of 15 ms, a speed of sound of 1500 m/s and if used a depth telemetry Full Scale period of 1000 ms.
|
Interrogation Rate
[sec]
|
Max Range
[meters]
|
|
|
|
W/O Telemetry
|
With Telemetry
|
|
|
|
|
|
2.0
|
1400
|
700
|
|
3.0
|
2200
|
1400
|
|
4.0
|
2900
|
2200
|
|
5.0
|
3700
|
2900
|