Two dimensional transform utilizing ultrasonic dispersive delay line

A system for simultaneously determining the frequency spectrum and direction of arrival of incoming signals, said system comprising:

• means for converting the incoming signals into acoustic energy;
• a layered half space dispersive delay line whose input is coupled to the output of said converting means so that an interference pattern will travel through said delay line as a series of acoustic pulses;
• means for converting the acoustic output of said delay line into electrical pulses;
• whereby, the position of one of the electrical pulses along an end edge of said delay line at a given time is related to the direction of arrival of one of the incoming signls and the time that said one electrical pulse exits said delay line determines the frequency of said incoming signal.

Apparatus for simultaneously determining a two dimensional spatial and frequency transform of a plurality of transmitted radio signals, comprising:

• (a) an integral number, M, of linearly spaced radiation receivers, arranged to receive the transmitted radio signals, each receiver thereby outputting a received signal;
• (b) a variable frequency sweeping periodic oscillator which outputs a sweep signal;
• (c) a plurality of mixers, a corresponding one for each of the M radiation receivers, each mixer connected to receive the received signal output from its associated radiation receiver and each mixer connected to receive the sweep signal, so that each mixer thereby outputs a corresponding one of M chirped signals;
• and
• (d) means for two-dimensional dispersive delay, connected to receive each of the M chirped signal outputs from their associated mixers, said delay means further arranged to provide a plurality, N, where N does not necessarily equal M, of transformed output signals in which, for each transformed output signal, one or more pulses are periodically output for each of the transmitted radio signals, and in which the relative position in time of each pulse indicates one component of the frequency transform of the transmitted signals and the relative position in space of each pulse indicates one component of the spatial transform of the transmitted signals. associated with one of the transformed output signals, thereby providing the N transformed output signals.