An indirect procedure for counting intermodulation products among narrow-band carriers [satellite links]

The problem of computing intermodulation generated by a large number of narrowband carriers is examined. In general, narrowband carriers sharing a nonlinear repeater may have different power levels and different spectral shapes. Therefore, different kinds of intermodulation products will appear. It is well known that replacing identical contiguous carriers by a noise band may lead to a poor approximation when baseband computations involving carriers with peaked spectral shapes (e.g. SCPC/FM) are considered. However, it is shown here that this noise band representation offers an effective way to calculate the total RF intermodulation power corresponding to each kind of product and can therefore be viewed as a means of indirectly counting intermodulation products