Signal synthesizer and method therefor

A digital synthesizer, comprising:

• a digital radio frequency memory (DRFM) for storing phase values and corresponding digital signals;
• a digital processing circuit receiving input from said DRFM, said circuit comprising a plurality of tapped delay lines, and a summer disposed to sum the output of said delay lines;
• and
• a signal modulator within each tapped delay line for imposing a frequency modulated and gain modulated signal and for independently synthesizing said signal wherein input to said tapped delay lines are phase values from said DRFM.

A method of synthesizing signals comprising:

• receiving digital samples of an analog signal produced by a physical object;
• storing said digital samples together with phase values corresponding to said samples in a digital radio frequency memory (DRFM);
• reading said phase values into a digital processing circuit;
• said circuit comprising a plurality of tapped delay lines, and a summer disposed to sum the output of said delay lines, wherein each tapped delay line comprises a signal modulator and wherein said reading causes said samples to traverse each said tapped delay to cause said summer to add the output of each of said delay lines;
• and
• imposing a frequency and gain modulation on a signal traversing each of said plurality of delay lines, the amount of frequency and gain modulation being preselected independent of the amount of frequency and gain modulation in each other delay line;
• and
• synthesizing a desired signal by using said modulated phase values from said DRFM.