Given a discrete-time, linear, shift-invariant channel with finite impulse response, the problem of designing finite-length input signals with bounded amplitude (l/sub /spl infin// norm) such that the corresponding output signals are maximally separated in amplitude (l/sub /spl infin// sense) is considered. In general, this is a nonconvex optimization problem, and appears to be computationally difficult. An optimization algorithm that seems to perform well is described. Optimized signal sets and associated minimum distances (minimum l/sub /spl infin// separation between two distinct channel outputs) are presented for some example impulse responses. A conjectured upper bound on the minimum distance is given that is easily computed given the impulse response of the channel, the number of inputs, and the input length. This upper bound is shown to be valid for a limited class of impulse response functions.>

The maximum data rate that can be reliably communicated given a linear, time-invariant, dispersive channel, a receiver that samples the channel output to within an accuracy of +or-d where d>0, and a transmitter with an output amplitude constraint is evaluated. For any dispersive channel the maximum rate depends on d and is finite. The transmitted waveforms must be designed so that two channel outputs associated with two distinct transmitted signals are separated in amplitude at a particular time by d. It is shown that given any channel impulse response with rational Laplace transform, there exists an optimal sets of inputs that are +or-A everywhere where A is the maximum allowable amplitude. Furthermore, in any finite time interval, each input changes sign a finite number of times. If the channel impulse response is a single decaying exponential, it is shown that simple binary signaling, in which A or -A, depending on the current message bit, is transmitted during each symbol interval, maximizes the data rate.>