US5221927A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lidar-acoustic sounding of the atmosphere
Assignee: UNITED STATE OF AMERICA COMMERCE, Secretary of
•
Filing: 1992-05-20
•
Granted: 1993-06-22
•
Expires: 2012-05-20
Abstract
Abstract A method of remote sensing of atmospheric conditions based on the detection of acoustic modulation of lidar returns in the atmosphere. The measured modulation is caused by density changes of the lidar scattering elements induced by an acoustic wave launched collinearly with the lidar. Applications are disclosed for measuring atmospheric humidity, cloud particle size, and temperature profiling.
Inventors
- 👤 Allan J. Palmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:36
CPC Classifications
G; G01; G01S; G01S17/00; G01S17/88; G01S17/95; G01S15/00; G01S15/88; G01S15/885; Y; Y02; Y02A; Y02A90/00; Y02A90/10
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
58 words
A method of remote sensing of atmospheric conditions, comprising the steps of: transmitting a lidar beam from a lidar transmitter at a predetermined direction into the atmosphere; transmitting an acoustic wave from an acoustic transmitter into the atmosphere collinearly with the lidar transmitter; and measuring acoustic modulation of lidar returns in the atmosphere to determine specific atmospheric conditions.
Claim 2
Independent Claim
58 words
A method of remote sensing of atmospheric conditions, comprising the steps of: transmitting a lidar beam from a lidar transmitter at a predetermined direction into the atmosphere; transmitting an acoustic wave from an acoustic transmitter into the atmosphere collinearly with the lidar transmitter; and measuring acoustic modulation of lidar returns in the atmosphere to determine specific atmospheric conditions.
Claim 3
Dependent Claim
31 words
The method of claim 1, further including the step of measuring differential acoustic absorption in an acoustic propagation path between the acoustic transmitter and lidar scattering volume to determine atmospheric humidity.
Claim 4
Dependent Claim
20 words
The method of claim 2, wherein modulation amplitude is measured as a function of acoustic frequency at a known range.
Claim 5
Dependent Claim
33 words
The method of claim 1, further including the step of measuring frequency dependence of movement of cloud particles in response to the transmitted acoustic wave to determine the size of the cloud particles.
Claim 6
Dependent Claim
16 words
The method of claim 4, wherein the transmitted acoustic wave has a frequency near 200 Hz.
Claim 7
Dependent Claim
37 words
The method of claim 1, further including the step of simultaneously transmitting two lidar beams having a wavenumber difference, .sup.Δ K, approximately equal to one-half of the acoustic wavenumber to determine the temperature profile of the atmosphere.
Claim 8
Dependent Claim
28 words
The method of claim 6, further including the step of determining a .sup.Δ K resonance line at the frequency of the selected acoustic wavenumber in the scattering volume.
Claim 9
Dependent Claim
32 words
The method of claim 7, further including the step of determining the temperature in the scattering volume from the frequency of the .sup.Δ K resonance line and a known vertical wind component.
Claim 10
Independent Claim
89 words
A method of remote sensing of atmospheric conditions, comprising the steps of: simultaneously transmitting two lidar beams having predetermined lidar wavenumbers and having a wavenumber difference, ΔK, the lidar beams being transmitted from a lidar transmitter at a predetermined direction into the atmosphere; transmitting an acoustic wave having a predetermined acoustic wavenumber from an acoustic transmitter into the atmosphere collinearly with the lidar transmitter, wherein ΔK is approximately equal to one-half the acoustic wavenumber; and measuring acoustic modulation of lidar returns in the atmosphere to determine specific atmospheric conditions.
Claim 11
Independent Claim
89 words
A method of remote sensing of atmospheric conditions, comprising the steps of: simultaneously transmitting two lidar beams having predetermined lidar wavenumbers and having a wavenumber difference, ΔK, the lidar beams being transmitted from a lidar transmitter at a predetermined direction into the atmosphere; transmitting an acoustic wave having a predetermined acoustic wavenumber from an acoustic transmitter into the atmosphere collinearly with the lidar transmitter, wherein ΔK is approximately equal to one-half the acoustic wavenumber; and measuring acoustic modulation of lidar returns in the atmosphere to determine specific atmospheric conditions.
Claim 12
Dependent Claim
27 words
The method of claim 9, further including the step of determining a ΔK resonance line at the frequency of the selected acoustic wavenumber in the scattering volume.
Claim 13
Dependent Claim
31 words
The method of claim 10, further including the step of determining the temperature in the scattering volume from the frequency of the ΔK resonance line and a known vertical wind component.
Claim 14
Dependent Claim
17 words
The method of claim 9 further including the step of determining the temperature profile of the atmosphere.
Claim 15
Dependent Claim
16 words
The method of claim 9 wherein the acoustic wavenumber is small compared to the lidar wavenumber.
Claim 16
Dependent Claim
14 words
The method of claim 13 further including the step of determining the atmospheric humidity.
Claim 17
Dependent Claim
16 words
The method of claim 13 further including the step of determining the size of cloud particles.
Claim 18
Dependent Claim
36 words
The method of claim 6 further including the step of choosing a basic processed signal to be a cross correlation spectrum between a scattered field product and a local oscillator phase locked with the acoustic wavenumber.
Claim 19
Dependent Claim
16 words
The method of claim 9; wherein, the lidar pulse length is longer than the acoustic wavelength.
Claim 20
Dependent Claim
16 words
The method of claim 1; wherein, the acoustic wavenumber is small compared to the lidar wavenumber.
Claim 21
Dependent Claim
17 words
The method of claim 2, wherein, the lidar pulse length is short compared to the acoustic wavelength.
Claim 22
Dependent Claim
17 words
The method of claim 4; wherein, the lidar pulse length is short compared to the acoustic wavelength.
References Cited (Backward Citations)
US2822536A
Cited
US4222265A
Cited
US4351188A
Cited
US4611912A
Cited
US4660038A
Cited
US4613938A
Cited
US4761650A
Cited
US5029999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-21 | 1996-12-21 | 1997-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-21 | 2000-12-21 | 2001-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-21 | 2004-12-21 | 2005-06-22 | $7700.00 | Window Closed / Lapsed |