only finitely many ratios of the sequence are usable. For example, if we require R >. 1.01, then we may use any n from 4 (R = 2) to 202 (R = 1.01) inclusive. The loop bandwidth in Figure 6 need be no wider than is required to track out the relative doppler rate between the remote and reference elements [10]. Figure 6 lends itself very well for use in a receiving array. We need only insert a clean-up loop between the reference element and the PCC’s in the initial node assembly, so that the reference signal applied to these PCC’s contains only the carrier phase, [], and no modulation. The phase detector in Figure 6 then serves as a demodulator whose output is fed to the data summer (through a delay distortion correcting processor if required) along with the data from the other PCC’s. The phase reference regenerator (PRR) for the circuit of Figure 6 may take various forms. The straightforward approach is illustrated by the circuit shown in Figure 7a which recovers the phase reference by the proper combination of the conjugate, [], and the pilot signal, [], Note that three mixers are required here, not just two; we cannot add two signals of the same frequency in a single mixer because the upper sideband would then have the same frequency as the second harmonic of the strong signal. We must add the pilot signal to the output of Ml in two stages, M2 and M3, in order to remove this "degeneracy." Figure 7b shows an indirect method of phase reference regeneration. Here, instead of recovering [] from [] and applying it as the phase reference to succeeding PCC’s as in Figure 7a, we use the PCC at the first order element to produce a "relative" conjugate,
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