A Consideration of the Moment 〈F(t)|F(t)|n〉Av in the Detection Problem
Peter J. Westervelt · The Journal of the Acoustical Society of America · 1951
The recognition of a signal having asymmetric wave form or harmonically related line structure will be discussed. A general consideration will be given to the average 〈F(t)|F(t)|n〉Av when F(t) consists of a signal plus noise. A simple circuit for taking the average when n − 1 consists of two square law rectifiers connected in parallel. The application of this circuit to the recognition of a signal consisting of fundamental and second harmonic terms will be treated in detail.