Principles of Modern Radar - Volume 2 1891121537

7.11 Problems 333[18] Raney, R.K., Luscombe, A.P., Langham, E.J., and Ahmed, S., “RADARSAT,” Proceedings ofthe IEEE, vol. 79, no. 6, pp. 839–849, 1991.[19] Canadian Space Agency Website for RADARSAT-1. Available at http://www.asccsa.gc.ca/eng/satellites/radarsat1/.[20] EarthView Advanced Precision Processor (APP) for SAR, Version 3.0 User’s Guide, AtlantisScientific Inc., Nepean, Ontario, Canada, 2003.[21] Sheen, D.R., Strawitch, C.M., and Lewis, T.B., “UHF Wideband SAR Design and PreliminaryResults,” in Proceedings of IGARSS’94: The International Geoscience and Remote SensingSymposium, vol. 1, pp. 289–291, 1994.[22] Goodman, R., Tummala, S., and Carrara, W.G., “Issues in Ultra-Wideband, Widebeam SARImage Formation,” Record of the IEEE 1995 National Radar Conference, pp. 479–485, 1995.[23] Sheen, D.R., VandenBerg, N.L., Shackman, S.J., Wiseman, D.L., Elenbogen, L.P., andRawson, R.F., “P-3 Ultra-Wideband SAR: Description and Examples,” IEEE AES Magazine,vol. 11, pp. 25–30, 1996.7.11 PROBLEMSYou have been tasked to design a dual-frequency stripmap SAR system suitable for deploymenton a small unmanned air vehicle and to implement and simulate image formationprocessing for this sensor. The two operating bands are L-band and X-band, with centerfrequencies of 1.0 GHz and 10 GHz, respectively. The specified down-range to scenecenter is 1 km, and the supported down-range and cross-range resolution is 1 m. A swathdepth of 200 m is desired. Assume the platform flies at 100 m/s and the grazing angle atswath center is 30 ◦ . Use 3 × 10 8 m/s as the speed of light in your calculations.1. [Basic calculations] What waveform bandwidth, antenna size (horizontal length), andalong-track sampling interval are required for this system (same for both frequencies)?How much integration angle is required at L-band and X-band? Determine theapproximate SAR baseline length using the arc length due to the integration angle.2. [DBS-AD and RMC] Determine whether quadratic phase is significant by calculatingthe maximum down-range beyond which quadratic phase is a concern. If quadraticphase is significant, calculate the maximum phase deviation at the beginning (or,equivalently, the end) of the SAR baseline with respect to the middle. Find the amountof total slant-range change over a full-resolution stripmap collection by using thehyperbolic PSR to calculate slant range to a scatter in the middle of the scene (x = 0,r = r 0 ) at the middle and ends of the SAR baseline. Compared with the down-rangeresolution, is migration of scatterers through range resolutions cells a problem?3. [RDA DOF] Calculate the depth of focus for the RDA technique employing the fullPSR in the frequency domain. What is the impact on RDA in light of the desiredswath depth?4. [PRF limit] What is the lower PRF limit for full (finest) stripmap cross-range resolution?What is the corresponding swath limit? Is finding a good PRF a challenge forthe desired swath depth?5. [ACR and system utility] What is the achieved area coverage rate and system utilitygiven the required swath depth? What is the potential system utility for finest crossrangeresolution and processing of the full beam extent?