A method of variable rate measurements in a device. The method generally
includes the steps of (A) generating an intermediate signal conveying
both a position of the device and a velocity of the device in response to
a plurality of navigation signals received from external the device, (B)
calculating an extrapolated position of the device at a second time based
on the position and the velocity both measured at a first time, (C)
adjusting an interval between the second time and a third time in
response to a difference between the extrapolated position and the
position measured at the second time and (D) generating a position signal
conveying the position and the velocity, wherein the third time occurs
after the second time and the second time occurs after the first time.