Would Time Difference of Arrival techniques combined with an array of four closely spaced antennas work with Gps signals as a means of determing the orentation of the antenna array vs the gps satellites ? (I'm thinking traditional TDOA techniques may not work with gps signals.)
Mike Naruta AA8K wrote: > Yes, but it is rather difficult to manufacture an > isotropic antenna. Unless the antenna is oriented > so as to present a normal hemisphere of same gain, > it might be theoretically possible to model the gain > versus direction, coupled with the knowledge of > location of satellites and received strength, to > determine the antenna's orientation with respect > to the world. > Now, there are lots of sources of error and > potential ambiguities for this process. As > you say, it is more straightforward to use a > magnetic field sensor. With position information > it should be easy to correct for true North. > Mike - AA8K > Magnus Danielson wrote: >> >> Yes, but you don't know in what direction from the unidirectional antenna. >> The antenna has no sense of direction, but the receiver knows very well in >> what direction relative north each sat is. The NMEA stream even include the >> coarse directions. >> >> If you has a steerable directional antenna, several antennas or moveable >> antenna, then you can convert the internal directions of the antenna into a >> north heading or heading towards anything else. >> >> But a normal unidirectional GPS antenna and associated receiver will be able >> to know where it is and from it provide very high precision direction >> relative north, but unless you move it or make any other form of aid, it >> will not be able to show the heading... but when you move around in with the >> car, then it can show it relative to the current heading of the car... as >> that forms a vector for which you can relate an angle... to north or to your >> intended destination. >> >> Cheers, >> Magnus >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. __________________________________________________________________ Yahoo! Canada Toolbar: Search from anywhere on the web, and bookmark your favourite sites. Download it now http://ca.toolbar.yahoo.com. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
