Passive coherent scatter radar interferometer implementation, observations, and analysis

[1] We have recently extended the passive radar technique to permit interferometric observation of ionospheric irregularities. We discuss the implementation of a passive radar interferometer at VHF frequencies and show observations of field-aligned irregularities in the high-latitude E region ionosphere. The interferometer achieves very fine azimuthal resolution (as fine as 0.1°, or 2 km at a range of 1000 km); thus we can form two-dimensional spatial images of the target volume. Many E region scatterers are compact, with transverse extent no greater than 10 km; this is significantly smaller than the beam width of most coherent radars. By tracking interferometric position, we can estimate the transverse drift of the scattering region. By coupling this information with the line of sight Doppler shift and using the dispersion relation for meter scale irregularities, we estimate electric fields and velocity shears within the scattering volume.

[1]  John K. Harmon,et al.  Planetary delay-Doppler radar and the long-code method , 2002, IEEE Trans. Geosci. Remote. Sens..

[2]  D. T. Farley,et al.  Plasma irregularities associated with a morning discrete auroral arc: Radar interferometer observations and theory , 1985 .

[3]  D. Hysell.  Radar imaging of equatorial F region irregularities with maximum entropy interferometry , 1996 .

[4]  P. Erickson,et al.  Simultaneous observations of E‐region coherent backscatter and electric field amplitude at F‐region heights with the Millstone Hill UHF Radar , 2000 .

[5]  J. Sahr,et al.  First passive radar observations of auroral E‐region irregularities , 1999 .

[6]  John D. Sahr,et al.  The Manastash Ridge radar: A passive bistatic radar for upper atmospheric radio science , 1997 .

[7]  P. E. Howland,et al.  Target tracking using television-based bistatic radar , 1999 .

[8]  Donald T. Farley,et al.  Radar interferometry: A new technique for studying plasma turbulence in the ionosphere , 1981 .

[9]  L. Isserlis.  ON A FORMULA FOR THE PRODUCT-MOMENT COEFFICIENT OF ANY ORDER OF A NORMAL FREQUENCY DISTRIBUTION IN ANY NUMBER OF VARIABLES , 1918 .

[10]  K. Schlegel,et al.  Coherent backscatter from ionospheric E-region plasma irregularities , 1996 .

[11]  John D. Sahr,et al.  Improved computational performance for distributed passive radar processing through channelised data , 2005 .

[12]  D. T. Farley,et al.  First VHF auroral radar interferometer observations , 1983 .

[13]  D. T. Farley.  Incoherent Scatter Correlation Function Measurements , 1969 .

[14]  C. Senior,et al.  Instantaneous mapping of high‐latitude convection with coherent HF radars , 1993 .