Photo Gallery - AN/MPQ-51 Range Only Radar

Sunset…

Type 968 mast head surveillance radar for the SEAWOLF missile system

Russia Upgrades Air Defenses

By Maxim Pyadushkin, Moscow

The Russian air force took delivery of the first Pantsyr-S short-range air-defense systems in March. The Pantsyrs will gradually replace the old Tunguska antiaircraft weapons. The first 10 systems were released from KBP Instrument Design Bureau’s assembly site in Tula and transported to Alabino, near Moscow, and will be part of the Victory Day parade in Red Square on May 9.

What’s unusual is that the first Pantsyr systems are being deployed to protect high-end surface-to-air missiles (SAMs) against aircraft, missiles and bombs.

Duga-3 – Photo gallery

Range-Doppler Imaging of Rotating Objects

Walker, Jack L., "Range-Doppler Imaging of Rotating Objects," Aerospace and Electronic Systems, IEEE Transactions on , vol.AES-16, no.1, pp.23,52, Jan. 1980
doi: 10.1109/TAES.1980.308875

Abstract: During the integration time required to obtain fine Dopplerfrequency resolution in a range-Doppler imaging radar, a point on a rotating object may move through several range and Doppler resolution cells and produce a smeared image. This motion can be compensated by storing the appropriately processed return pulse, and the angular coordinates are determined by the angular coordinates of the radar antenna. The resulting stored data represents the three-dimensional Fourier transform of the object reflectivity density, and hence can be processed by an inverse Fourier transformation. Also included is an analysis of the three-dimensional radar/object geometry with separate source and receiver locations. The effects of various system aberrations are investigated and experimental results from a microwave test range which demonstrate the image improvement are presented.

Reference

Antenna Effects in Depolarization Measurements

Blanchard, A.J.; Jean, Buford Randall, "Antenna Effects in Depolarization Measurements," IEEE Transactions on Geoscience and Remote Sensing, vol.GE-21, no.1, pp.113,117, Jan. 1983, doi: 10.1109/TGRS.1983.350537

Abstract: The depolarization of electromagnetic energy scattered from natural terrain has been of interest to experimenters and theoreticians for many years. However, the reported measurements have not agreed with theoreticaly predicted results. Boresight axial ratio has commonly been used as a figure of merit to describe the polarization isolation properties of the measurement system antennas. Since depolarization measurements from terrain involve extended targets which fill the full antenna beam, boresight axial ratio is often an inadequate measure of antenna polarization purity. This paper describes antenna isolation characteristics which impact the quality of the depolarized measurements. Representative calculations demonstrate the effects of nonideal antenna systems on the observed measurements. A criterion for antenna specification is given which will provide high-quality cross-polarized measurements.

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