Method and apparatus for modulating a signal

摘要

A modulated signal (10) is sinusoidal wave signal wherein each half wave cycle carries a digital data value associated with an amount of its amplitude. A positive half wave cycle with an amplitude of M encodes a binary level zero digital data value while a positive half wave cycle with an amplitude of M+x encodes a binary level one digital data value. Similarly, a negative half wave cycle with an amplitude of -M encodes a binary level zero digital data value while a negative half wave cycle with an amplitude of -M-x encodes a binary level one digital data value. The positive and negative half wave cycles may transport dual portions of a channel at the same frequency as a modulated signal (20) for either a dual transmission capability or as a full duplex bidirectional transmit/receive channel. Each half wave cycle may also be modulated to carry a plurality of digital data values beyond binary level zero and one through selection of four or more amplitude levels to generate a modulated signal (30). A modulated signal (40) may also provide digital data value representations in each quarter wave of the sinusoidal wave signal to further increase bandwidth capability.