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pNav Versions Comparison

Cold Start

Ideal Conditions ¹⁾

pNav coldstart takes app. 60 seconds and is app. 10% faster than pNav2.

Real Conditions²⁾

A cold start of pNav is problematic and can take up to hours. A cold start of pNav2 is reliable and takes at most a couple of minutes; see the Navigation of Rotating Satellite in the datasheet.

Reaqusition

Position fix exists

Fast using Almanach data for both pNav and pNav2.

No position fix

Same problem as Real Conditions Acquisition. pNav2 has no problem, while pNav is terribly slow, and reacquisition is not guaranteed.

Tracking Sensitivity

pNav can track only open sky satellites.

The tracking loops of pNav2 were optimized to track weak signals; see the Navigation of Rotating Satellite in the datasheet.

¹⁾ The antenna is pointed towards the zenith; the satellite is attitude-controlled and stable, with a perfect view of the sky.

²⁾ At least one condition of Ideal Conditions is not satisfied.