摘要 |
FIELD: fiber-optical digital communication through waveguides which have significant chromatic dispersion at effective wavelength. SUBSTANCE: if digital signal to be transmitted is converted to optical signal by means of amplitude modulation, length of transmission piece is limited. If frequency modulation (also known as frequency shift keying) is used instead of amplitude modulation, length of transmission piece is increased significantly, but receiving part should be also equipped with appropriate receiver. Described system involves use of simple optical receiver which is not designed for frequency modulation of amplitude. This is possible since chromatic dispersion in waveguide and different traveling time of signal components of different wavelength <EMI ID=0.91 HE=9 WI=15 TI=CHI> leads to alternation of amplitude from source frequency modulation during transmission through waveguide. Alternation of amplitude encodes digital signal to be transmitted. EFFECT: increased functional capabilities. 16 cl, 11 dwg |