Modulation by Linear Maximal Shift Register Sequences: Amplitude, Biphase and Complement-Phase Modulation
MICHIGAN UNIV ANN ARBOR COOLEY ELECTRONICS LAB
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The report describes the use of linear-maximal shift-register sequences either to amplitude modulate AM or to angle modulate a sinusoidal carrier. Two cases of angle modulation are considered biphase modulation BM and complement-phase modulation CM. In biphase modulation the carrier angle switches between pi2 and - pi2, whereas in complement-phase modulation the carrier angle switches between pi4 and - pi4. It is shown that the ratio of the average power to the peak power for AM is only one-half as large as for either BM or CM. On the other hand, the ratio of the carrier power to the average power for either AM or CM is one-half, but for BM this ratio is approximately zero. Finally, a replica-correlation technique for use with any of the three modulations is described.