6.4 Presentation of target information

  6.4.1.1 Target information may be provided by radar target tracking and/or by reported target information from the Automatic Identification System (AIS).

  6.4.1.2 The operation of the radar target tracking function and the processing of reported AIS information, including the number of targets presented, related to screen size, is defined within the Performance standards for radar equipment, as adopted by the Organization. The presentation of radar target tracking and AIS information is defined within these performance standards.

  6.4.1.3 As far as practical, the user interface and data format for operating, displaying and indicating radar tracking and AIS information should be consistent.

  6.4.2.1 There should be an indication when the target tracking and/or reported target processing/display capacity is about to be exceeded.

  6.4.2.2 There should be an indication when the target tracking and/or reported target processing/display capacity has been exceeded.

  6.4.3.1 To ensure that the clarity of the total presentation is not substantially impaired, it should be possible to filter the presentation of sleeping AIS targets (e.g. by target range, CPA/TCPA or AIS target class A/B, etc.).

  6.4.3.2 If a filter is applied, there should be a clear and permanent indication. The filter criteria in use should be readily available.

  6.4.3.3 It should not be possible to remove individual AIS targets from the display.

  6.4.4.1 If zones for the automatic activation of AIS targets are provided, they should be the same as for automatic radar target acquisition, if available. Any user defined zones (e.g. acquisition/activation zones) in use should be presented in graphical form.

  6.4.4.2 In addition, sleeping AIS targets should be automatically activated when meeting user defined parameters (e.g. target range, CPA/TCPA or AIS target class A/B).

  6.4.5.1 Targets should be presented with their relevant symbols according to SN/Circ.243.

  6.4.5.2 AIS information should be graphically presented either as sleeping or activated targets.

  6.4.5.3 The course and speed of a tracked radar target or reported AIS target should be indicated by a vector that clearly shows the predicted motion. The vector time (length) should be consistent for presentation of any target regardless of its source.

  6.4.5.4 The presentation of vector symbols should be consistent irrespective of the source of information. The presentation mode should be clearly and permanently indicated, including for example: True/Relative vector, vector time and vector stabilisation.

  6.4.5.5 The orientation of the AIS target symbol should indicate its heading. If the heading information is not received, the orientation of the AIS symbol should be aligned to the COG. When available, the turn or rate of turn (ROT) indicator and/or the path prediction should indicate the manoeuvre of an activated AIS target.

  6.4.5.6 A consistent common reference point should be used for the alignment of tracked target symbols and AIS target symbols with other information on the same display.

  6.4.5.7 On large scale/low range displays, a means to present a true scale outline of an activated AIS target should be provided.

  6.4.5.8 It should be possible to display the past positions of activated targets.

  6.4.6.1 A target selected for the display of its alphanumeric information should be identified by the relevant symbol. If more than one target is selected for data display, the symbols and the corresponding data should be clearly identified.

  6.4.6.2 There should be a clear indication to show that the target data is derived from radar or AIS or from a combination of these.

  6.4.6.3 For each selected tracked radar target the following data should be presented in alphanumeric form: Source(s) of data, measured range of target, measured bearing of target, predicted target range at the closest point of approach (CPA), predicted time to CPA (TCPA), true course of target, true speed of target. Additional target information should be provided on request.

  6.4.6.4 For each selected AIS target the following data should be presented in alphanumeric form: Source of data, ship's identification, position and its quality, calculated range of target, calculated bearing of target, CPA, TCPA, COG, SOG, navigational status. Ship's heading and rate of turn should also be made available. Additional target information should be provided on request.

  6.4.6.5 If the received AIS information is incomplete, the absent information should be clearly indicated in the target data field as missing.

  6.4.6.6 The data should be displayed and continually updated, until another target is selected for data display or until the window is closed.

  6.4.6.7 Means should be provided to present own ship AIS data on request.

  6.4.6.8 The alphanumeric displayed data should not obscure graphically presented operational information.

  6.4.7.1 A clear indication of the status of the alarms and of the alarm criteria should be given.

  6.4.7.2 A CPA/TCPA alarm of a tracked radar or activated AIS target should be clearly indicated and the target should be clearly marked by a dangerous target symbol.

  6.4.7.3 If a user defined acquisition/activation zone facility is provided, a target entering the zone should be clearly identified with the relevant symbol and for tracked radar targets an alarm should be given. The zone should be identified with the relevant symbology, and should be applicable to tracked radar and AIS targets.

  6.4.7.4 The last position of a lost target should be clearly marked by a lost target symbol on the display, and the lost target alarm should be given. The lost target symbol should disappear if the signal is received again, or after the alarm has been acknowledged. There should be a clear indication whether the lost target alarm function for AIS targets is enabled or disabled.

  6.4.8.1 An automatic target association function serves to avoid the presentation of two target symbols for the same physical target. If target data from AIS and radar tracking are both available and if the AIS and radar information are considered as one target, then as a default condition, the activated AIS target symbol and the alphanumeric AIS target data should be automatically selected and displayed. The user should have the option to change the default condition to the display of tracked radar targets and should be permitted to select either radar tracking or AIS alphanumeric data.

  6.4.8.2 If the AIS and radar information are considered as two distinct targets, one activated AIS target and one tracked radar target should be displayed. No alarm should be raised.

 The AIS presentation status should be indicated as follows:

 A trial manoeuvre simulation should be clearly identified by the relevant symbol positioned astern of own ship within the operational display area of the screen.