Networked waveform system

• US 20100079330A1
• Filed: 05/07/2009
• Published: 04/01/2010
• Est. Priority Date: 05/07/2008
• Status: Active Grant

• Current Assignee: Colorado State University Research Foundation
• Original Assignee: Colorado State University Research Foundation
• Inventors: Bharadwaj, Nitin, Venkatachalam, Chandrasekaran
• Granted Patent: US 8,077,074 B2
• Time in Patent Office: Days
• US Class Current: 342/59
• CPC Class Codes: G01S 13/003 Bistatic radar systems; Multistatic radar systems
• CPC Class Codes: G01S 13/582 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 13/951 ground based
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/024 using polarisation effects in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195
• 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

Certain embodiments provide a network waveform system that can include multiple radars disposed at different geographical positions within an environment. The multiple radars may be configured to transmit a network waveform. The network waveform may include multiple radar waveforms. Each radar waveform of the multiple waveforms may be transmitted by a specific radar of the multiple radars. The system can also include a computer system coupled with the multiple radars that can include a processor and a memory. The memory may be configured to store information including data received from the multiple radars, data processed by the processor, and processing code executable by the processor. The processing code may include instructions to receive output data from the multiple radars resulting from the transmitted network waveform instructions to jointly process the output data from the multiple radars to determine a measurement of the environment based on the network waveform.

Claims

1. A networked waveform system for resolving radar measurement ambiguities, comprising:

a plurality of radars disposed at different geographical positions within an environment and being configured to transmit a network waveform, wherein the network waveform includes a plurality of radar waveforms such that each radar waveform of the plurality of radar waveforms is transmitted by a specific radar of the plurality of radars;

a computer system coupled with the plurality of radars including a processor and a memory, the memory being configured to store information including data received from the plurality of radars, data processed by the processor, and processing code executable by the processor, wherein the processing code includes;

instructions to receive output data from the plurality of radars resulting from the transmitted network waveform; and

instructions to jointly process the output data from the plurality of radars to determine a measurement of the environment based on the network waveform.

2. The networked waveform system of claim 1, wherein the instructions to determine a measurement of the environment includes solving an optimization problem given

$\mathrm{by}$



w ^ = arg 





min w 



Gw - v ^ k 

2 ,

where {circumflex over (v)}_k is a measured Doppler velocity vector, w=[u v]^T is a wind vector whose elements are velocity components in a horizontal plane, G is a geometric transformation relating the wind vector to the measured Doppler velocity, and ŵ

is a retrieved wind velocity vector.

3. The networked waveform system of claim 1, wherein each radar waveform of the plurality of radar waveforms includes at least one pulse repetition frequency.

4. The networked waveform system of claim 3, wherein at least a subset of the plurality of radars transmits a radar waveform including at least a second pulse repetition frequency.

5. The networked waveform system of claim 1, wherein the processor code further comprises instructions to transmit instructions to the plurality of radars to transmit a specific network waveform.

6. The networked waveform system of claim 1, wherein the measurement of the environment comprises a velocity measurement.

7. The networked waveform system of claim 6, wherein the processor code is configured to determine a velocity greater than 100 meters per second.

8. The networked waveform system of claim 1, wherein the measurement of the environment comprises a reflectivity measurement.

9. The networked waveform system of claim 1, wherein the processor code is configured to determine whether the transmitted waveform is a networked waveform.

10. The networked waveform system of claim 1, wherein at least one of the plurality of radars is at least one of an X-band radar, a monostatic radar, or a magnetron radar.

11. The networked waveform system of claim 1, wherein the processor code further comprises instructions to determine a dealiased wind field.

12. A method for resolving radar measurement ambiguities, comprising:

transmitting a plurality of radar waveforms from a plurality of radars disposed at geographically different positions within an environment;

receiving from the plurality of radars output data resulting from the transmitted plurality of radar waveforms, wherein at least a subset of the output data is aliased;

processing the output data from the plurality of radars jointly;

determining a dealiased measurement of the environment from the processed output data.

13. The method for resolving radar measurement ambiguities of claim 12, wherein determining a dealiased measurement of the environment includes solving an optimization problem given by

$\hat{w}=\arg $





min w 



Gw - v ^ k 

2 ,

where {circumflex over (v)}_k is the measured Doppler velocity vector, w=[u v]^T is a wind vector whose elements are velocity components in a horizontal plane, G is a geometric transformation relating the wind vector to the measured Doppler velocity, ŵ

is a retrieved wind velocity vector.

14. The method for resolving radar measurement ambiguities of claim 12, wherein the plurality of radar waveforms is a network waveform.

15. The method for resolving radar measurement ambiguities of claim 12, wherein the each radar waveforms of the plurality of radar waveforms includes at least one pulse repetition frequency.

16. The method for resolving radar measurement ambiguities of claim 15, wherein at least a subset of the plurality of radars is each configured to transmit a waveform including at least a second pulse repetition frequency.

17. The method for resolving radar measurement ambiguities of claim 12, further comprising transmitting instructions to the plurality of radars to transmit a specific network waveform.

18. The method for resolving radar measurement ambiguities of claim 12, wherein the dealiased measurement is a velocity measurement.

19. The method for resolving radar measurement ambiguities of claim 18, wherein the dealiased measurement determines a velocity measurement at least 100 meters per second.

20. The method for resolving radar measurement ambiguities of claim 12, wherein the dealiased measurement is a reflectivity measurement.

21. The method for resolving radar measurement ambiguities of claim 12, wherein at least one of the plurality of radars is at least one of an X-band radar, a monostatic radar, or a magnetron radar.

22. The method for resolving radar measurement ambiguities of claim 12, further comprising determining a dealiased wind field from the processed output data.

23. A network radar system, comprising:

transmitting means for transmitting a network waveform from a plurality of radars, wherein the network waveform comprises a plurality of radar waveforms;

receiving means for receiving output data from the plurality of radars resulting from the transmitted network waveform; and

processing means for processing jointly the output data from the plurality of radars to determine a measurement of the environment.

24. A method of Doppler radar measurement, comprising:

determining a velocity that is at least 100 meters per second using radar data from a plurality of radars, wherein each of the plurality of radars is configured to provide radar data that can support velocity measurements less than 100 meters per second.