Sequence discriminators and their use in frequency division multiplex-communication systems

A simple theory of networks exhibiting sequence discrimination and their use for producing quadrature signals is first presented. A channel unit employing sequence discriminators (SD's), namely, passive (RC), passive with feedback, and active designs are discussed. A channel unit employing SD's and the associated modulation and demodulation schemes are suggested. Statistical sensitivity results and experimental results using thick film resistor and NPO chip capacitor implementations are also given. These indicate that the (SD) approach for single-sideband generation and detection is very promising in FDM applications. This technique which uses resistors, capacitors, and commercial integrated circuits is simple to implement and requires no specially developed technologies.