| 摘要 |
FIELD: television and sound diffusion engineering. SUBSTANCE: method designed for distributing information programs in mobile networks includes digital compression of image signals and accompanying sound during transmission, their multiplexing to obtain compressed information television signal, noise-suppressing channel coding, carrier modulation using orthogonal frequency division of channels, and radiation; during reception it includes carrier signal demodulation, division of digital image signals and accompanying sound, their digital decoding and reproduction; transmission also includes subsampling and compression of image signals, addition of random value phase increment assigned out of set of random values known in advance to each signal subcarrier upon modulating carriers of orthogonal frequency division of channels, frequency conversion of highfrequency signal shaped in this way, and its radiation over narrowband , such as 250-500 MHz, municipal mobile channel; upon demodulation random-value phase increment introduced during transmission is subtracted in each signal subcarrier and during reproduction subsampling introduced during transmission is eliminated and image signal is returned to original form. Proposed method ensures no-break reception of television programs and/or audio stereophonic broadcasting in multiple-beam environment with rapidly changing phase structure of field during flow of traffic. EFFECT: enhanced reliability of television program reception. 2 cl, 2 dwg
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