This correspondence deals with the development of a practical approach for the assessment of intermodulation distortion in modern cable television (CATV) systems operating over the 400 MHz range. In particular, Volterra series expansions are used in establishing appropriate high-frequency models for the description of such wide-band CATV channels. Furthermore, experimental measurements made on a typical system are utilized to illustrate the development of Volterra models which may be used subsequently in the prediction of intermodulation distortion in such systems.

This paper considers the performance of digital data transmission in nonlinear channels with memory. The analysis is based on the application of a particular form of Volterra series representation for the nonlinear system describing the transmission channel. First, expressions are derived for the output mean and power spectral density under certain conditions. Next, the paper presents a computationally convenient expression for the error rate involved in such transmission.

This paper investigates the characterization of nonlinear distortion produced in FDM systems under high-frequency operation, by using noise loading techniques. By employing a general Volterra-based model, the paper develops an appropriate noise loading technique for the assessment of nonlinear distortion in such wide-band transmission systems. The advantage of using Volterra series representation is that it takes account of system nonlinear-memory behavior in a combined formulation.

Walsh-type signals exciting memoryless power-law systems are considered. The input is assumed to consist of a sum of weighted Walsh functions. A method is given for finding the weights of the Walsh functions in the output when the input is a finite Walsh series. It is shown that the fast Walsh transform can be used to facilitate the necessary computation.