Spherical codes for M-ary code shift keying

The author presents a number of spherical codes which can be implemented in practice and which are capable of providing significant coding gains on the AWGN channel. The geometrical approach to code design used also provides an alternative design method to the conventional algebraic approach. Other codes could easily be designed along similar lines, for a desired code rate or for some other desired characteristic. The principles given will help in the design of optimal codes. The approach has the additional advantage that it results in codes with a high degree of symmetry and a well-defined structure, which may be helpful in the design of a decoder