15 Generally, a shipborne PNT-DP is made up of three functional blocks:
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.1 Pre-processing;
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.2 Main processing; and
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.3 Post-processing.
16 The pre-processing function extracts, evaluates, selects and
synchronizes input (sensor and service) data (including the associated integrity
data) to preselect the applicable techniques to determine PNT and integrity output
data.
17 The architecture of the PNT-DP is shown in figure 1.

Figure 1: Architecture of PNT-DP
18 The main processing function generates the PNT output data and associated
integrity and status data.
19 The post-processing function generates the output messages by coding
the PNT output data (PNT, integrity, and status data) into specified data protocols.