Power suppression at the Nyquist frequency for pilot-aided PAM and QAM systems

Two low-redundancy codes for in-band pilot insertion are introduced. KF10 suppresses the baseband PAM and the modulated QAM signal power at the Nyquist frequency so that the dual-pilot tone calibration technique of recent interest can be arranged to convey both a symbol timing and a carrier reference to the receiver. OF00 suppresses the signal power at zero as well as the Nyquist frequency and allows the utilization of a triple-pilot scheme which provides, in addition to a symbol timing, a carrier reference with no 180 degrees phase ambiguity.<
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