Method and apparatus for doppler velocity de-aliasing

A method of operating a processing apparatus of a radar system for real time de-aliasing of Doppler velocity data comprising the steps of:

• storing initialization data for a Windfield Model;
• processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• operating on said processed velocity data by examining adjacent velocity data of radar dwells in an azimuthal direction to minimize azimuthal velocity differences;
• updating said Windfield Model with said de-aliased velocity data and in accordance with a trend in radial velocity samples (TV), a trend in average of the velocities (TA), and velocity differences between adjacent Model sectors.

A method of operating a processing apparatus of a radar system for real time de-aliasing of Doppler velocity data comprising the steps of:

• checking for dual scans and when present storing said velocity data of a first scan of said dual scans, said dual scans comprising repeated scans at constant elevation angle;
• processing said velocity data of said dual scans using a velocity difference correction function, said dual scans having different pulse repetition frequencies;
• storing initialization data for a Windfield Model;
• processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• and
• updating said Windfield Model with said de-aliased velocity data.

A method of operating a processing apparatus of a radar system for real time de-aliasing of Doppler velocity data comprising the steps of:

• checking for dual scans and when present storing said velocity data of a first scan of said dual scans;
• processing said velocity data of said dual scans using a velocity difference correction function, said dual scans having different pulse repetition frequencies;
• storing initialization data for a Windfield Model;
• processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• operating on said processed velocity data by examining adjacent velocity data of radar dwells in an azimuthal direction to minimize azimuthal shear velocity differences;
• and
• updating said Windfield Model with said de-aliased velocity data and in accordance with a trend in radial velocity samples (TV), a trend in average of the velocities (TA), and velocity differences between adjacent Model sectors.

Apparatus for real time -de-aliasing of Doppler velocity data comprising:

• means for storing initialization data for a Windfield Model;
• means for providing a variable resolution of said Windfield Model depending on an elevation angle and retaining a vector component of the true wind in a plurality of sectors of said Windfield Model;
• means coupled to said storing means and a radar signal processing means for processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• means for operating on said processed velocity data by examining adjacent velocity data of said radar dwells in an azimuthal direction to minimize azimuthal shear velocity differences;
• and
• means for updating said Windfield Model with said de-aliased velocity data.

Apparatus for real time de-aliasing of Doppler velocity data comprising:

• means for storing initialization data of a Windfield Model;
• means coupled to said storing means and a radar signal processing means for processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• means for operating on said processed velocity data by examining adjacent velocity data of said radar dwell in an azimuthal direction to minimize azimuthal shear velocity differences;
• and
• means for updating said Windfield Model with said de-aliased velocity data and in accordance with a trend in radial velocity samples (TV), a trend in average of the velocities (TA), and velocity differences between adjacent Model sectors.

Apparatus for real time de-aliasing of Doppler velocity data comprising:

• means for checking for dual scans and when present storing said velocity data of a first scan of dual scans, said dual scans comprising repeated scans at constant elevation angle;
• means coupled to said storing means and a radar signal processing means for processing said velocity data of said dual scans using a velocity difference correction function, said dual scans having different pulse repetition frequencies;
• means for providing initialization data to a Windfield Model in said storing means;
• and
• said processing means further comprises means for processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• and
• said processing means further comprises means for updating said Windfield Model with said de-aliased velocity data.

Apparatus for real time de-aliasing of Doppler velocity data comprising:

• means for storing velocity data and a plurality of routines for de-aliasing said velocity data;
• means coupled to said storing means and a radar signal processing means for checking for dual scans and when present storing said velocity data of a first scan of said dual scans in said storing means comprising repeated scans at constant elevation angles;
• means included in said checking means for processing said velocity data of said dual scans using a velocity difference correction function, said dual scans having different pulse repetition frequencies;
• means for providing initialization data to a Windfield Model in said storing means;
• a process radials routine in said storing means for processing each range gate return signal of said velocity data along a radar dwell by examining adjacent data along said radial dwell and de-aliasing in accordance with an average of previous range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• a minimize azimuthal shear routine in said storing means for operating on said velocity data by examining adjacent velocity data of said radar dwells in an azimuthal direction to minimize azimuthal shear velocity differences;
• and
• an Update Windfield Model routine in said storing means for updating said Windfield Model with said de-aliased velocity data during the processing of dual scans and a single scan.

A radar system having apparatus for real time de-aliasing of Doppler velocity data comprising:

• means for transmitting a radar beam of said radar system at different pulse repetition frequencies;
• means coupled to said transmitting means for processing return signals from said radar beam to obtain said velocity data;
• means coupled to said signal processing means for performing said real time de-aliasing of said velocity data;
• means for storing in said de-aliasing performing means initialization data for a Windfield Model;
• means for adjusting a variable resolution of said Windfield Model depending on an elevation angle and retaining a vector component of the true wind in a plurality of sectors of said Windfield Model;
• first routine means in said de-aliasing performing means for checking for dual scans and when present storing in said storing means said velocity data of a first scan of said dual scans and processing said velocity data of said dual scans using a velocity difference correction function, said dual scans having different pulse repetition frequencies at constant elevation angle;
• second routine means in said de-aliasing performing means for processing each range gate return signal of said velocity data along a radar dwell of said radar beam by examining adjacent data along said radar dwell and de-aliasing in accordance with an average of precious range gates when said velocity data is continuous and when said velocity data is not continuous using data from said Windfield Model;
• third routine means in said de-aliasing performing means for operating on said velocity data by examining adjacent velocity data of said radar dwells in an azimuthal direction to minimize azimuthal shear velocity differences;
• an
• fourth routine means in said de-aliasing performing means for updating said Windfield Model during the processing of dual scans and a single scan.