| 摘要 |
<p>A satellite communications apparatus has a corrector (20) for reducing distortion of a signal in a communication channel. The corrector is formed by a forward model (42) representative of a pre-calculated estimate of non-linearity and group delay of the satellite transmission/reception channel from the input to the up sampler (21) through to the input of the down sampler (34). The forward model may also comprise a model of magnitude response of a satellite input multiplexer filter and output multiplexer filter. Cascaded identical stages of the corrector may be provided so that distortion in the channel is successively reduced towards zero by each successive stage. An initial approximator which is substantially the inverse of the distorting function of the forward model may be provided.</p> |
