We consider a linear array whose collinear radiating elements are periodically spaced at a distance which is a multiple of the carrier wavelength. Each radiating element may introduce a phase delay of either 0 or 180° according to the control bit stream for that particular element. The control bit streams are each different phases of specially constructed binary sequences. The duration of a control sequence bit times the speed of light is also a multiple of the carrier wavelength. This modulation architecture achieves two objectives. The first objective is main beam pointing. Modulating the different elements by different phases of specially constructed sequences results in a novel method of phased array control. One particular set of sequences considered yields an antenna pattern governed by an elegant result from finite group theory. The second objective is spectrum spreading. Because each element can be modeled as a linear time-invariant device, we can employ the Wiener-Lee relation to calculate the power spectral density of the radiated beam.

© 1984 Optical Society of America

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