2 p.

The Jicamarca antenna is the largest radar antenna in the world. It is a flat and almost horizontal array of cross-dipoles, covering an area of 300 m by 300 m (9 Ha). It has a center frequency of 50 MHz with a bnndwidth of 1 MHz (determined by power combiners and splitters at the feed point of the antenna).

In this paper we discuss many aspects of codes and decoding and their applications to MST experimenta. This includes Barker codes and longer individual codes, and then complementary codes and other code sets. We discuss software decoding and also hardware decoders and coherent integrators.

During the Condor campaign a number of instruments were set up in Peru to support the rocket experiments. In this series of papers we report on the results of the experiments designed to study the equatorial F region. In this overview paper we summarize the main results as well as report upon the macroscopic developments of spread F as evidenced by data from backscatter radars, from scintillation observations, and from digital ionosonde meaurements. In this latter regard, we argue here that at least two factors other than the classical gravitational Rayleigh-Taylor plasma instability process must operate to yield the longest-scale horizontal organization of spread F structures. The horizontal scale typical of plume separation distances can be explained by invoking the effect of a shear in the plasma flow, although detailed comparison with theory seems to require shear frequencies a bit h...