Robert Ehrlich skrev den Wed, 04 Feb 2004
18:21:08 +0000:

I understand clearly how the TCAS can determine range and altitude (by
timing the return and decoding the encoded altitude), but how can it
determine the bearing? directional antennas coupled with compass
information?

Directional receiving antenna was correct, compass information was not.
You con't care about the bearing, only the direction. Which won't be too
exact anyway.

Cheers,
Fred