Title :
A new method for computing intermodulation products in SCPC systems
Author_Institution :
Commun. Res. Lab., Minist. of Posts & Telecommun., Kashima, Japan
Abstract :
Many authors have already published papers on methods for computing intermodulation products in satellite communications systems, in which the signals are amplified by nonlinear travelling wave tube (TWT) amplifiers. This paper describes a simple new method for calculating the output power spectrum of nonlinear satellite transponders in SCPC systems. This method uses exponential functions to describe the input-output characteristics of TWT and assumes input signals as a Gaussian process. The intermodulation spectra can be represented by simple closed-form functions which are simple to calculate and require less computation time than previously proposed methods.<>
Keywords :
Gaussian processes; intermodulation; modulation; nonlinear network analysis; radiofrequency amplifiers; satellite communication; spectral analysis; transponders; travelling wave amplifiers; Gaussian process; SCPC systems; exponential functions; input signals; input-output characteristics; intermodulation products; intermodulation spectra; losed-form functions; nonlinear TWT amplifiers; nonlinear satellite transponders; output power spectrum; satellite communications systems; Gaussian processes; Power amplifiers; Power generation; Satellite communication; Signal processing; Transponders;
Journal_Title :
Communications, IEEE Transactions on