High resolution frequency wave number spectra for detection and location of weak signals

Claim 2

In a system for monitoring time varying radiation to determine the source location, frequency, and power by the production of a k-plane response of the system, the combination which comprises: a. an array of sensors, the elements of which are located in predetermined relation one to the other, b. means for producing a full house set of power-density spectra including autopower density of signals from all said detectors and cross-power density between all possible pairs of said detectors, c. means for adding the autopower density spectra from one of said detectors to the autopower density spectra from all of said detectors to produce a modified full house set of spectra in which each element of the set is a summation, and d. means for registering said modified full house set to facilitate production of two-dimensional high resolution kplane response.

Claim 3

The system of claim 1 wherein said sensors are seismometers positioned in an array at the earth''s surface.

Claim 4

The system of claim 1 wherein said sensors are seisometers positioned in a two-dimensional horizontal array at the earth''s surface.

Claim 5

The system of claim 1 wherein said sensors are seismometers positioned in an array at the earth''s surface in symmetry with respect to one of said sensors, and wherein means are provided for adding the cross-correlation signal from said one of said sensors to itself and to the cross-correlation signals from all the remaining sensors.

Claim 6

In the production of k-plane response from time varying energy arriving at a monitor station, the steps of: a. detecting said energy at a plurality of points in an array at said station, b. generating a full set of signals representative of the autopower density spectra of energy detected at all of said points, c. generating a second set of signals representative of the cross-power density spectra between energy detected at all of said points, d. adding one of the signals from said first set to itself and to each of the remaining signals of said first set to produce a modified set of autopower density spectra signals, and e. registering said modified set and said second set.

Claim 7

In the production of k-plane response from time varying energy arriving at a monitor station, the steps of: a. detecting said energy at a plurality of points in an array at said station, b. generating a full set of signals representative of the autopower density spectra of energy detected at all of said points, c. generating a second set of signals representative of the cross-power density spectra between energy detected at all of said points, d. adding one of the signals from said first set to itself and to each of the remaining signals of said first set to produce a modified set of autopower density spectra signals, and e. registering said modified set and said second set.

Claim 8

In the production of k-plane response from time varying energy arriving at a monitor station, the steps of: a. detecting said energy at a plurality of points in an array at said station, and b. causing an automatically operable system to perform the steps of: i. generating a full set of signals representative of the autopower density spectra of energy detected at all of said points, ii. generating a second set of signals representative of the cross-power density spectra between energy detected at all of said points, iii. adding one of the signals from said first set to itself and to each of the remaining signals of said first set to produce a modified set of autopower density spectra signals, and iv. registering said modified set and said second set.

Claim 9

In the production of k-plane response from time varying energy arriving at a monitor station, the steps of: a. detecting said energy at a plurality of points in an array at said station, and b. causing an automatically operable system to perform the steps of: i. generating a full set of signals representative of the autopower density spectra of energy detected at all of said points, ii. generating a second set of signals representative of the cross-power density spectra between energy detected at all of said points, iii. adding one of the signals from said first set to itself and to each of the remaining signals of said first set to produce a modified set of autopower density spectra signals, and iv. registering said modified set and said second set.

Claim 10

The method of claim 6 wherein seismic energy is detected at said points.

Claim 11

The method of claim 6 wherein electromagnetic energy is detectEd at said points.

Claim 12

The method of claim 6 wherein magnetic energy is detected at said points.

Claim 13

The method of claim 7 wherein the autopower density spectra for the signal generated at a center point in said array is added to itself and to the autopower spectra of signals generated at all other points in said array.

Claim 14

In a system where time varying radiation is monitored and a k-plane response is produced utilizing signals from an array of sensors located in predetermined relation one to the other to supply signals to a processing means to produce a full house set of power-density spectra signals including autopower density of signals from all said detectors and cross-power density between signals from all pairs of said detectors and which in turn supply processing means which produces said k-plane response from said autopower density spectra signals and said cross-power density spectra signals as signal-plus-noise inputs and estimated signal inputs, the new use to determine the location, frequency, and power of each radiation source which comprises: a. separately modifying the autopower density spectra signals from all of said detectors by the addition thereto of a given constant signal for application as said signal-plus-noise inputs to said processing means, and b. applying said given constant signal to said processing means as the estimated signal input.

Claim 15

In a system where time varying radiation is monitored and a k-plane response is produced utilizing signals from an array of sensors located in predetermined relation one to the other to supply signals to a processing means to produce a full house set of power-density spectra signals including autopower density of signals from all said detectors and cross-power density between signals from all pairs of said detectors and which in turn supply processing means which produces said k-plane response from said autopower density spectra signals and said cross-power density spectra signals as signal-plus-noise inputs and estimated signal inputs, the new use to determine the location, frequency, and power of each radiation source which comprises: a. separately modifying the autopower density spectra signals from all of said detectors by the addition thereto of a given constant signal for application as said signal-plus-noise inputs to said processing means, and b. applying said given constant signal to said processing means as the estimated signal input.

Claim 16

The new use set forth in claim 11 wherein said constant signal has a proportional value in the region of 1.0 relative to the autopower density spectra for the signal from one of said sensors for maintaining at a minimum the variation in the representation in k-plane response of the power from a given source.

Claim 17

The new use set forth in claim 11 wherein said constant signal has a proportional value in the region of 0.01 relative to the autopower density spectra for the signal from one of said sensors for maximizing the resolution in said k-plane response of weak sources.

Claim 18

The new use set forth in claim 11 wherein said constant signal is the autopower density spectrum signaL of the signal from one of said detectors.