"The techniques for decoding in hardware received signals transmitted by phase‐coded mesosphere‐stratosphere‐troposphere (MST) radars are reviewed. The designs consist of digital and analog types which resemble filters or correlators in their operation. A new analog design is presented, and a discussion of the choice between hardware and software decoding is given. The number of bits required for digital coherent integrators and decoders is discussed, and the use of fast Fourier transforms for decoding is described."
