Abstract: To generate a pulse for ranging, a kernel is convolved with a spreading sequence. The spreading sequence is parametrized by one or more ordered (length, sparsity) pairs, such that the first sparsity differs from the bit length of the kernel and/or a subsequent sparsity differs from the product of the immediately preceding length and the immediately preceding sparsity. Alternatively, a kernel is convolved with an ordered plurality of spreading sequences, all but the first of which may be non-binary. The pulse is launched towards a target. The reflection from the target is transformed to a received reflection, compressed by deconvolution of the spreading sequence, and post-processed to provide a range to the target and/or a direction of arrival from the target.

Abstract: A system for measuring the height of bin content includes a transmitter for transmitting an acoustic pulse towards the upper surface of the content, a non-collinear receiver array for receiving an echo of the pulse and producing signals in response to the echo, and a processing apparatus for computing one or more directions of arrival of the signals from the upper surface to the array along with corresponding measured distances. Preferably, the receivers are transducers that also serve as transmitters. Two or more such measured distances constitute a map of the upper surface for estimating the quantity of the bin content. Preferably, the system includes a pulse shaper and repeater for optimizing the pulse shape relative to the signals.