| 摘要 |
A method and apparatus for modulating and demodulating information for bandlimited communication is disclosed. Serialized digital data is divided into equal segments which are arranged in parallel. Each data segment is converted into a digital representation of a modulating value (either frequency, phase, amplitude or some combination). Each such digital representation is then combined in a particular manner with a number of digital representations of different carrier frequencies. This overlapping, whereby each digital representation of a carrier frequency is combined with several digital words in such a way that the corresponding analog carrier frequency would be modulated, and each digital word so "modulates" several carrier frequency representations, is called shoring. The resulting digital signals are processed to construct a digital representation of an analog signal which is the superposition, or amplitude sum over time, of all the different modulated carrier frequencies. The digital representation is then converted into an analog signal for transmission.
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