AN INVESTIGATION OF FACTORS WHICH DEGRADE PHASE ACCURACY IN A VLF RELATIVE NAVIGATION SYSTEM.
Abstract
A VLF relative navigation system makes use of the fact that, at any given point on the earth, phase delay of a received VLF signal is highly stable and predictable. As the receiver is physically moved, phase delay changes linearly with distance from the transmitting station, so that by keeping track of the phase delay of the received signal from several VLF stations, one may keep an accurate plot of geographical position. Two problems experienced in measuring phase delay are the diurnal shift and long path interference. An investigation is made into a method of predicting the diurnal phase shift and the resultant phase due to simultaneous reception of long and short path signals. Also investigated is a receiving antenna having a cardioid shaped radiation pattern which could provide discrimination against long path signals. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1966
- Accession Number
- AD0807391
Entities
People
- Gerry Lee Preston
- John Douglas Mckay
Organizations
- Naval Postgraduate School