Spectra of biternary digital f.m.

Spectra of digital f.m. have been published recently for general n-level transmission. However, biternary signals, as used in p.c.m. systems, are not covered by the published formulas and require a special treatment. Spectrum density and spectrum distribution are derived for biternary transmission, numerical curves are presented for certain values of f.m. deviation, and the results are compared with ordinary binary transmission.