Wide band clear air scatter doppler radar

• US 9,310,481 B2
• Filed: 03/13/2013
• Issued: 04/12/2016
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Foster-Miller Incorporated (Thermo Fisher Scientific Incorporated)
• Original Assignee: LogLinear Group LLC
• Inventors: Henderson, Mark, Bradley, Marshall
• Primary Examiner(s): Bythrow, Peter
• Application Number:
  US13/801,778
• Publication Number:
  US 20130321200A1
• Time in Patent Office: 1,126 Days
• Field of Search: 342/26.R, 342/26.A, 342/26.B, 342/26.C, 342/26.D
• US Class Current: 1/1
• CPC Class Codes: G01S 13/583 using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves and based upon the Doppler effect resulting from movement of targets
• CPC Class Codes: G01S 13/589 measuring the velocity vector
• CPC Class Codes: G01S 13/951 ground based
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

Systems and methods for measuring wind speed and direction in clear air conditions using a wide band Doppler radar in accordance with embodiments of the invention are disclosed. In one embodiment of the invention, a wide band Doppler radar system includes an antenna assembly includes at least one transmit antenna and at least one receive antenna; a transceiver connected to the antenna assembly configured to transmit a radar beam includes a transmit signal on a Ka-band carrier frequency and receive a backscattered radar beam includes a carrier frequency that is frequency shifted relative to the transmitted Ka-band carrier frequency of the backscattered radar beam; a data acquisition system connected to the transceiver configured to estimate a wind velocity vector by calculating a Doppler shift between at least one transmitted radar beam and at least one received backscattered radar beam.

Claims

1. A wide band Doppler radar system comprising:

an antenna assembly comprising at least one transmit antenna and at least one receive antenna, where;

each of the at least one transmit antenna is configured to transmit a radar beam comprising a transmit signal on a Ka-band carrier frequency; and

each of the at least one receive antenna is configured to receive a backscattered radar beam comprising a carrier frequency that is frequency shifted relative to the transmitted Ka-band carrier frequency of the backscattered radar beam;

a transceiver connected to the antenna assembly configured to;

transmit a radar beam comprising a transmit signal on a Ka-band carrier frequency using each of the at least one transmit antenna; and

receive a backscattered radar beam comprising a carrier frequency that is frequency shifted relative to the transmitted Ka-band carrier frequency of the backscattered radar beam using each of the at least one receive antenna; and

a data acquisition system connected to the transceiver configured to estimate a wind velocity vector in clear air conditions by calculating a Doppler shift between at least one transmitted radar beam and at least one received backscattered radar beam.

2. A wide band Doppler radar system of claim 1, wherein the antenna assembly further comprises a horn antenna having waveguide flanges.

3. A wide band Doppler radar system of claim 1, wherein the transceiver operates between 33.3 GHz and 33.5 GHz.

4. A wide band Doppler radar system of claim 1, wherein the transceiver operates as a frequency modulated continuous wave (FMCW) radar.

5. A wide band Doppler radar system of claim 1, wherein the antenna assembly further comprises 4 transmit antennas.

6. A wide band Doppler radar system of claim 5, wherein the antenna assembly further comprises 4 receive antennas.

7. A wide band Doppler radar system of claim 5, wherein the transceiver connected to the antenna assembly is further configured to transmit radar beams that separated by 90 degrees in azimuth.

8. A wide band Doppler radar system of claim 7, wherein the transceiver connected to the antenna assembly is further configured to transmit radar beams that tilted 80 degrees up from the horizontal.

9. A wide band Doppler radar system of claim 7, wherein the data acquisition system is configured to determine the wind velocity vector from the Doppler shift based on the velocities, V_i of the transmitted and received backscattered radar beams transmitted where i is the number of the radar beam and where:

V_i=−

sin(Ψ

_r+φ

_i)cos θ

v_x−

cos(Ψ

_r+φ

_i)cos θ

v_y−

sin θ

v_z

where Ψ

_r is the azimuthal orientation of the radar beam, φ

_i is the radar beam steering angle, and θ

is the tilt angle of the radar relative to the horizontal.

10. A wide band Doppler radar system of claim 9, wherein the data acquisition system is configured to determine the wind velocity vector

V_wind=(v_x,v_y,v_z)

from the Doppler shift based on transmitted and received backscattered radar beams transmitted where:

11. A method of estimating wind speed and direction using a wide band Doppler radar system comprising:

configuring at least one transmit antenna to transmit a radar beam comprising a transmit signal on a Ka-band carrier frequency;

configuring at least one receive antenna too receive a backscattered radar beam comprising a carrier frequency that is frequency shifted relative to the transmitted Ka-band carrier frequency of the backscattered radar beam;

transmitting a radar beam comprising a transmit signal on a Ka-band carrier frequency using each of the at least one transmit antenna;

receiving a backscattered radar beam comprising a carrier frequency that is frequency shifted relative to the transmitted Ka-band carrier frequency of the backscattered radar beam using each of the at least one receive antenna; and

estimating a wind velocity vector by calculating a Doppler shift between at least one transmitted radar beam and at least one received backscattered radar beam.

12. A method of claim 11, wherein the at least one the transmit antenna and the at least one receive antenna are parts of a horn antenna having waveguide flanges.

13. A method of claim 11, wherein transmitting a radar beam comprising a transmit signal on a Ka-band carrier frequency further comprises operating between 33.3 GHz and 33.5 GHz.

14. A method of claim 11, wherein transmitting a radar beam comprising a transmit signal on a Ka-band carrier frequency further comprises generating a continuous wave.

15. A method of claim 11, wherein configuring at least one transmit antenna to transmit a radar beam further comprises configuring 4 transmit antennas.

16. A method of claim 15, wherein configuring at least one receive antenna too receive a backscattered radar beam further comprises configuring 4 receive antennas.

17. A method of claim 16, wherein the radar beams are separated by 90 degrees in azimuth.

18. A method of claim 17, wherein the radar beams are tilted 80 degrees up from the horizontal.

19. A method of claim 17, wherein the transmitting and receiving are performed at a single location.

20. A method of claim 19, wherein the estimation is calculated from a transmitted radar beam transmitted in the direction of true north.