| 摘要 |
PURPOSE: To eliminate errors due to multiple paths by removing the contribution part of multi-path signals from reception signals, utilizing remaining non- damaged line-of-sight signals and deciding accurate propagation time from a signal source to a receiver. CONSTITUTION: A receiver processor 30 is provided with integrators 45K (K is an integer whose interval is 1-N), samples from multipliers 40K are updated after respective integration cycles T and a digital signal processor 50 reads them by input 51K. The processor 50 utilizes the read samples and calculates the set of equations I-III by a prescribed program. In the case of a GPS(global positioning) system, it is better to select the integration cycle T to be less than 10 ms so as to obtain an appropriate data estimated value and it is not absolutely required that the processor 50 calculate the entire set of the equations I-III once every 10 ms. In the case that only ionized layer change achieves an important role, it is sufficient to calculate the set of the equations I-III at the frequency of once every second or less and the data of a local generator and frequency deviation are decided from the estimated phase.
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