Bistatic RCS measurement on rough metallic background surface
Publish date: 2010-03-15
Report number: FOI-R--2964--SE
Pages: 30
Written in: Swedish
Keywords:
- radar
- bistatic
- reflectivity
- RCS
- X-band
- radar calibration
- Gauss surface
- Lilla Gåra
Abstract
This report accounts for parts of one work package in a Swedish-French cooperation on target and background signatures. The purpose is to report to our partners in this cooperation and to document methods, results and conclusions. Bistatic measurements on a PEC rough reference surface have been conducted in September 2009 at the FOI outdoor facility "Lilla Gåra". The measurements were a continuation (cover larger angular space) of the work that has been reported in June 2009. The bistatic reflectivity of the PEC surface with Gaussian height statistics having H=0.0072 m and correlation length L=0.0191 m has been measured for a series of scattering geometries. An object-free calibration procedure has been applied. ISAR imaging and inversion back to RCS data has, together with zero-doppler filtering, been used to check for and remove background contributions. Data has been measured in the frequency range 8 to 12 GHz but due to truncation artefacts only the range 8.5 to 11.5 GHz was used to estimate the reflectivities at 10 GHz. The reflectivity of the Gaussian surface increases with transmitter and receiver depression angles, although the incoherent part is expected to fall again at high angles. The results will be used for validating different types of background models.