Methods and apparatus for the generation and transmission of signals for echo location and other signalling purposes, as in geophysical exploration
US4204278A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 3, 1978 |
| Grant date | May 20, 1980 |
| Priority date | — |
| Expiry date | Jul 3, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Quasi periodic pulse trains are generated and swept in repetition frequency over an octave. Spectral harmonics of the pulse trains which prevent the trains from having a constant or "flat" power spectrum over a frequency range much greater than an octave are reduced or eliminated by adjusting the shape of the pulses in the trains. By means of selecting the timing of the pulses, other harmonics are reduced or preferentially augmented. The spectral energy of the signals which are generated during a transmission interval is of the type which possesses an autocorrelation function with a narrow main lobe and low side lobe levels which is especially suitable for echo location purposes such as in geophysical exploration in which seismograms are constructed by cross correlation of the signals which are transmitted with those which are received from the geological reflection surfaces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.