Method for transmitting information on the basis of quadrature amplitude modulation

摘要

Method for transmitting information on the basis of quadrature amplitude modulation. Methods are known for coding the pulses in PAM or PCM by means of the amplitudes of the half-waves or cycles of an alternating current and then in each case adding 2 alternating coding currents which are phase-shifted through 90@ in relation to one another and transmitting them as an alternating coding current. Furthermore, it is also known, for example, to quarter the frequency of an alternating coding current by extracting the samples in time division multiplexing with a 90@-degree phase shift and by transferring them onto the half-waves or cycles of 4 alternating coding currents phase-shifted through 90@, two of which can then be added together once more. In the invention, the two summation alternating currents can then be added together once more so that 4 channels can be transmitted with one alternating coding current by modifying the phase angle of the 4 alternating coding currents or samples for transmission, with temporary storage if required, in such a way that their summation alternating currents are phase-shifted through 90@ in relation to one another and can thus be added together once more. <IMAGE>