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In this paper, we explore the capabilities of the Monostatic-Bistatic Theorem (MBT) applied to Radar Cross Section (RCS) in low frequency. Originally, the validity of this theorem has been shown in high frequency for targets whose RCS is produced by elementary interactions (specular reflection in particular). We are interested in aerial platforms and in particular some Low Observable targets that have relatively "pure" geometries limiting the presence of complex interactions. Several variants of the MBT from the field of electromagnetism [1][2][3] and acoustics [4] are used. Their performances are compared from data obtained from a MoM method that is recognized to produce accurate scattering data. To highlight the discrepancies produced by the different variants, we use both a metric to compare the quality of the bistatic holograms obtained and also radar imaging which allows locating the areas of the target where the echoes are not correctly restored.
The Conex Antenna, Radar, and Measurement Equipment Lab (CARAMEL) is a ten-element VHF antenna array that operates from 30 MHz-120 MHz with an attached lab space. This array was developed for use in low frequency Radar Cross Section (RCS) measurements. The antenna elements support both vertical and horizontal polarizations. The antenna was designed using a genetic algorithm, employing the fragmented aperture technique; measured and modeled data will be presented. The attached lab space is air conditioned and provisioned for rack mounted equipment. The structure uses a modified 20' Conex shipping container where an entire sidewall has been replaced with a reinforced composite radome for the antennas. The overall mechanical frame design included a Finite Element Analysis to ensure structural integrity. The system is intended for long-term standalone use as an outdoor measurement radar system but can be moved using standard shipping container methods. The structure was shipped using a standard cargo carrier from Atlanta, Georgia to White Sands, New Mexico.
Additive manufacturing has become a popular alternative to traditional CAM techniques, as it has reached a suitable maturity and accuracy for microwave applications. The main advantage of the additive technologies is that the manufacturing can be performed directly from the 3D CAD model, available from the numerical simulation of the antenna, without significant modifications. This is a highly desirable feature, in particular for time and cost critical applications such as prototyping and manufacturing of small quantities of antennas. Different 3D-printing/additive manufacturing technologies are available in industry today. The purpose of the paper is an investigation on the accuracy and repeatability of the Selective Laser Melting (SLM) manufacturing technique applied to the construction of a batch of 15 broad band fully metallic chocked horns, operating at X/Ku band, manufactured in parallel. Manufacturing accuracy and repeatability has been evaluated using RF parameters as performance indicators comparing measured data and high accuracy simulations. The radiation patterns have been correlated to the numerical reference using the Equivalent Noise Level, while manufacturing repeatability is quantified on input matching by defining an interference level. These indicators have also been compared to state-of-the-art values commonly found for traditional manufacturing.
A hybrid method that combines the finite element method (FEM), the Floquet mode analysis and the shooting and bouncing ray method (SBR) is presented to solve the quiet-zone field in large tapered anechoic chambers. In the method, the field equivalence principle is employed to replace the throat of the tapered chamber by a set of equivalent electric and magnetic currents. The Floquet mode analysis is employed to approximate the rest of the absorber lined walls by virtual surfaces with equivalent reflection coefficients. The total quiet-zone field then becomes the superposition of the field radiated by the equivalent currents, and the field scattered by the virtual reflective surfaces. The scattered field is calculated from the SBR method. The required equivalent currents of the throat and the reflection coefficients of absorber array walls are computed with the use of the FEM, which allows the considerations of the complex structure and near-field interaction. Numerical examples are presented to demonstrate the feasibility of the proposed method.
This paper presents two methods for measuring dynamic antenna patterns of phased arrays in a compensated compact range. The first method uses the turntable of the compact range to counter steer the antenna beam. The dynamic pattern is created by measuring single points of the pattern over time. This method is successfully tested, and the measurement results show the effect of phase jumps during the steering process. The second method extends the range of application to fast steering phased arrays by decoupling the antenna scan angle and the azimuth angle of the turntable.
New requirements in the field of autonomous driving and large bandwidth telecommunication are currently driving the research in millimeter-wave technologies, which resulted in many novel applications such as automotive radar sensing, vital signs monitoring and security scanners. Experimental data on scattering phenomena is however only scarcely available in this frequency domain. In this work, a new mono- and bistatic radar cross section (RCS) measurement facility is detailed, addressing in particular angular dependent reflection and transmission characterization of special RF material, e.g. radome or absorbing material and complex functional material (frequency selective surfaces, metamaterials), RCS measurements for the system design of novel radar devices and functions or for the benchmark of novel computational electromagnetics methods. This versatile measurement system is fully polarimetric and operates at W-band frequencies (75 to 110 GHz) in an anechoic chamber. Moreover, the mechanical assembly is capable of 360° target rotation and a large variation of the bistatic angle (25° to 335°). The system uses two identical horn lens antennas with an opening angle of 3° placed at a distance of 1 m from the target. The static transceiver is fed through an orthomode transducer (OMT) combining horizontal and vertical polarized waves from standard VNA frequency extenders. A compact and lightweight receiving unit rotating around the target was built from an equal OMT and a pair of frequency down-converters connected to low noise amplifiers increasing the dynamic range. The cross-polarization isolation of the OMTs is better than 23 dB and the signal to noise ratio in the anechoic chamber is 60 dB. In this paper, the facility including the mm-wave system is deeply studied along with exemplary measurements such as the permittivity determination of a thin polyester film through Brewster angle determination. A polarimetric calibration is adapted, relying on canonical targets complemented by a novel highly cross-polarizing wire mesh fabricated in screen printing with highly conductive inks. Using a double slit experiment, the accuracy of the mechanical positioning system was determined to be better than 0.1°. The presented RCS measurements are in good agreement with analytical and numerical simulation.
Time and Direction of Arrival (TADOA) analysis of field probe data has been an accepted method for characterizing stray signals in an antenna measurement range for many years ([1], [2]). Recent uncertainty investigations at the OneRY range have shown a need for increased resolution to isolate and characterize energy in TADOA images so that resources can be carefully applied to reduce the uncertainty from these stray signals. This is accomplished by modeling the TADAO image as the solution to a Basis Pursuit (BP) l1 minimization problem. This paper outlines the model development and shows concrete examples from OneRY field probe data where BP allows for the identification of stray energy which was previously difficult to find. We also show how the BP optimization context can be using to remove contamination from the data through the inclusion of additional basis functions ([3]). I.J. Gupta, E.K. Walton, W.D. Burnside, “Time and Direction of Arrival Estimation of Stray Signals in a RCS/Antenna Range,” Proc. of 18th Annual Meeting of the Antenna Measurement Techniques Association (AMTA '96), Seattle WA, September 30-October 3, 1996, pp. 411-416. I.J. Gupta, T.D. Moore, “Time Domain Processing of Range Probe Data for Stray Signal Analysis,” Proc. of 21st Annual Meeting of the Antenna Measurement Techniques Association (AMTA '99), Monterey Bay CA, October 4-8, 1999, pp. 213-218. B.E. Fischer, I.J. LaHaie, M.H. Hawks, T. Conn, “On the use of Basis Pursuit and a Forward Operator Dictionary to Separate Specific Background Types from Target RCS Data,” Proc. of 36th Annual Meeting of the Antenna Measurement Techniques Association (AMTA '14), Tucson AZ, October 12-17, 2014, pp. 85-90.
For features of very weak scattering while masked by background and clutter, care must be taken in the measurement design as well as data processing, in order to extract the true RCS values. A good example of flush-mounted fasteners for a low-observable (LO) aircraft, arranged in an array, was reported by Lutz, Mensa, and Vaccaro [1]. In the Boeing 9-77 range, retro-reflectors (called retros) were routinely taped on a test-body for monitoring its 3-D locations and angles during measurements. Though the retro’s RCS may be several orders below that of a test-body, a challenge was to discover their exact values. In the millimeter wave range (MMWR), we measured 2-D arrays of retros arranged in both square and hexagonal lattices taped onto a flat metal surface pitched 20o down. RCS measurements were made as a function of frequency and aspect angle. From the 2-D FFT images, the nominal RCS for a retro in VV polarization was found to be -75 dBsm, independent of the geometry and number of retros even down to one unit-cell [2]. But for the HH polarization, there is no backscattering from such a flat metal surface. References [1]. J. Lutz, D. Mensa, and K. Vaccaro, "RCS measurements of LO features on a test body," Proc. 21st AMTA, pp. 320-325 (1999). [2]. P. S. P. Wei and J. P. Rupp, " RCS measurements on arrays of weak scatterers enhanced by diffraction," Proc. 26th AMTA, pp. 263-268 (2004). ---------------------------------------------- ** Sam Wei is at: 4123 - 205th Ave. SE, Sammamish, WA 98075-9600. Email: paxwei3@gmail.com, Tel. (425) 392-0175
Among different measurement techniques for the wall reflectivity, an RCS_based technique has been implemented and test results are reported. For most of the anechoic chambers, the factory acceptance test and a quality-control check is sufficient for the customers to be sure that the absorbers used to line their chamber are good enough. In some cases, a quiet-zone reflectivity measurement will certify that the chamber yields the quietness as needed for the specific application of the customer. This last technique is mostly used in the far-filed ranges. However, in some anechoic chambers, e. g. some compact ranges, the customer wants to know the effect of the installation and the shipment on the final absorber installed in the room. That is why, they ask for a wall reflectivity measurement to see the reflectivity of the absorbers after being installed. The main problem to be solved when talking about wall reflectivity is the un-wanted clutter in the room which needs to be compensated for. Last year at AMTA 2016, we have introduced a clutter-removal technique to reduce the unwanted shattering levels. That was supported by some lab implementations and accordingly some limitations in the implementation. This paper, explains the result of the first practical on-site test done in an anechoic chamber. Many different points in the chamber have been tested and a detailed discussion of the results are brought to view.
Millimeter wave vehicular radar operating in the 77 GHz band for automatic emergency breaking (AEB) applications in detecting vehicles, pedestrians, and bicyclists, test data has shown that the radar cross section (RCS) of a target decreases significantly with distance at short range distances typically measured by automotive radar systems, where the reliable detection is most critical. Some attribute this reduction to a reducing illumination spot size from the antenna beam pattern. Another theory points to the spherical phase front due to measurement in the Fresnel region of the target, when the distance for the far-field zone is not met. The illumination of the target depends on the antenna patterns of the radar, whereas the Fresnel region effects depend on the target geometry and size. Due to fluctuations in measured data for RCS as a function of range in the near-field, upper and lower bounds for the target RCS versus range have been determined empirically as a method for describing the expected RCS of target. So far, the range-dependent RCS bounds used in AEB test protocols have been determined empirically. The study discussed in this paper aims to study the underlying physics that produces range-dependent RCS in near field and provide analytical model of such behavior. The resultant analytical model can then be used to objectively determine the RCS upper and lower bounds according to the radar system parameters such as antenna patterns and height. A comparison of the analytically predicted model and empirical near-field RCS as a function of range data will be presented for pedestrian, bicyclist, and vehicle targets.
RCS measurements are usually performed in 3 steps in an anechoic chamber. First, the reflectivity of the target is measured. Then a reference measurement (generally without the target) is performed. Finally, a calibration standard of known RCS is used as a reference target. The main goal of the calibration phase is to transform raw measurements of reflectivity (S11 parameter in dB) into RCS (in dBsm) through the determination of the inverse transfer function of the entire RCS measurement layout. This calibration process indirectly converts the received electric field into a complex scattering coefficient. Moreover, it establishes a phase reference relatively to the rotation center of the target positioning system. The most frequently used standards are metallic spheres which have advantageous characteristics: monostatic RCS is well known by Mie-Series and independent of azimuth and elevation. However, manufacturing a perfect metallic lightweight sphere using conventional techniques include many issues that can generate defects in the spherical shape. The purpose of this paper is to evaluate the geometric and RCS performances of metallic spheres obtained from metal additive manufacturing systems using Selective Laser Melting (SLM) solutions. SLM is a fast prototyping technique designed to melt and fuse metallic powders together. On the one hand, these metallic spheres were checked by a 3D scanner in order to quantify the potential shape defects and on the other hand, RCS measurements were performed in an anechoic chamber. All these results will be presented in the final paper and compared with theoretical RCS data.
Radar signature measurements of targets with or without camouflage in different backgrounds using airborne SAR is complicated and expensive. Measurements at many orientations as well as illumination angles have to be performed for each target for completeness. A more efficient solution is to use ground based ISAR measurements of the desired targets and then blend these images into measured SAR scenes. We are developing a SAR-ISAR blending method where the target and background are modelled by point scatterer representations. This can be formulated as an inverse problem described by the equation Ax = y, (1) where A is a forward operator describing the model, x is the image and y is the measured RCS data. The point scatterer representations for the target and the SAR background are determined by solving (1). The main contribution of this paper is that we use a combination of L1 and L2 regularization methods to solve the inverse problem. The target measured by ISAR is sparse in the image domain and (1) is therefore solved efficiently using a L1 regularization method. However, the SAR background is not sparse in the image domain and (1) is therefore solved using a L2 regularization method. We use the following procedure: Define the operators A and At, where At is the conjugate transpose of A. The same operators are used for both the target and the background. Solve (1) using L1 regularization for the target measured using ISAR. Edit the target point scatterers so that only target related scatterers are included. Solve (1) using L2 regularization for the SAR background. Edit the background point scatterers by removing the shadowed region, alternatively attenuate if there is a camouflage net. Combine the edited point scatterers for the target and background and calculate the RCS for the combination. Add estimated system noise. Create a blended SAR-image. The method is demonstrated with ISAR measurements of a full-scale target, with and without camouflage, signature extraction and blending into a SAR background. We find that the method provides an efficient way of evaluating measured target signatures in measured backgrounds.
Abstract— Tilting the receive end wall of a compact range anechoic chamber to improve Radar Cross-Section (RCS) measurements has been a tool of the trade used since the earliest days of anechoic chambers. A preliminary analysis using geometrical optics (GO) validates this technique. The GO approach however ignores the backscattering modes from the reflected waves from a field of absorber. In this paper, a series of numerical experiments are performed comparing a straight wall and a tilted wall to show the effects on both the quiet zone and the energy reflected back towards the source antenna. Two Absorber covered walls are simulated. Both walls are illuminated with a standard gain horn (SGH). The effects of a wall tilted back 20° are computed. The simulations are done for 72-inch long absorber for the frequency range covering from 500 MHz to 1 GHz. The ripple on a 10 ft (3.05 m) quiet zone (QZ) is measured for the vertical wall and the tilted wall. In addition to the QZ analysis a time-domain analysis is performed. The reflected pulse at the excitation antenna is compared for the two back wall configurations Results show that tilting the wall improves measurements at some frequencies but causes a higher return at other frequencies; indicating this method does not provide a broadband advantage. Keywords: Anechoic Chamber Design, Radar Cross Section Measurements, Geometrical Optics
In June of this year, DSC completed the installation of a turnkey RCS measurement system that is used for in-process verification (IPV) and final component validation using standard near field QC techniques in an echoic chamber. The delivered system included a radar, antennas, shroud, ogive pylon, foam column, elevators for each – column and pylon, automated pit covers, test bodies, target transport carts, and calibration targets. The system automatically loads test objects on the correct target support system, requiring no action by the operator to connect a target onto the azimuth over elevation “tophat” positioner – it is all automatic. The user interface is designed to be operated by production line workers, greatly reducing the need for experienced RCS test engineers. Simple pass/fail indicators are shown to the test technicians, while a full detailed data set is stored for engineering review and analysis. A wall display guides users through a test sequence for target handling and starting the radar. Radar data collection of all azimuth and elevation angles and target motion are initiated from a single button push. This is followed by all data processing necessary to conduct the ATP on the parts providing a pass/fail report on dozens of parameters. The application of production line quality automation to RCS measurements improves the repeatability of the measurements, greatly reduces both measurement time as well as overhead time, and allows systems operators to become more interchangeable. This highly successful project, which was completed on-time and on-budget, will be discussed. This discussion will include radar performance, antenna and shroud design, target handling, data processing and analysis software, and the control system that automates all the functions that are required for RCS measurements.
Automatic emergency braking (AEB) and collision imminent braking are beginning to be implemented by major automotive manufactures. AEB systems utilize automotive radar sensors operating in the 77 GHz frequency band for target detection. These said systems are capable of providing warning directly to the vehicle driver and when necessary apply automatic emergency braking. The effectiveness of such systems need to be accurately tested using standards and test procedures that are yet to be agreed upon among international automobile industry and government agencies. The Euro NCAP vehicle target (EVT) is the current European standard for AEB testing scenarios. The main goal of this research effort was developing a compact W-band radar echo emulator (REE) to be used for evaluating automotive pre-collision systems (PCS) operating in the 77 GHz frequency band. The proposed REE is capable of receiving radar signals from the PCS radar mounted on the vehicle under test (VUT) and then transmits modified radar signals back to PCS radar bearing the similar signatures (temporal, spectral, and pattern) as the Euro NCAP Vehicle Target (EVT). REE eliminates the need for the front vehicle target to produce radar responses which is currently accomplished with complicated arrangement of RF absorbers and reflectors as in the EVT and other vehicle surrogates. The adoption of REE means that the vehicle target only needs to bear optical signatures similar to an actual vehicle, and thus can be made with a much simpler balloon structure. Measurements present for the characterization of the Euro NCAP EVT over distance as well as the calibrated radar cross section (RCS). From this simply target model the REE echo power is empirically determined. The REE solution to PCS testing scenarios offers an easily adaptable return power various targets can be emulated with a single module.
Wave scattering from a perfectly conducting sphere provides an important example for theoretical studies as well as RCS calibrations [1, 2]. At the Boeing 9-77 Range and the Millimeter Wave Range in Seattle, we measured spheres of large and small diameters, supported by strings or a foam tower, and through a wide range of frequencies. In addition to co-polarized calibration, the emphasis was also on uncertainty analysis in order to verify that the experiments carried out under different conditions were mutually consistent [3]. Aside from the well-defined conditions for an indoor range, metal spheres may be dropped from the air free fall while being measured [4]. A news article on January 5, 2016, reported that three metal spheres were picked up in three provinces in northern Vietnam [5]. Though details of the experiments were obscure, from the pictures they happened to correspond to spheres of sizes from large to small. Based on our experiences, some speculation will be discussed. References [1]. E. F. Knott, "Radar Cross Section Measurements," (Van Nostrand Reinhold, New York, 1993), pp. 176-180, (on spheres and the Mie series). [2]. E. F. Knott, E. F. Shaeffer, and M. T. Tuley, "Radar Cross Section," (Artech House, 2nd ed, 1993), pp. 86 & 234-235, (on creeping waves). [3]. P. S. P. Wei, A. W. Reed, C. N. Ericksen, and J. P. Rupp, “Uncertainty Analysis and Inter-Range Comparison on RCS Measurements from Spheres,” Proc. 26th AMTA, pp. 294-299 (2004). [4]. “Mysterious silver balls fall down on town; can the black helicopters be far behind?” By Steve Vogel, The Seattle Times, August 7, 2000, (from the Washington Post). [5]. “3 mysterious spheres fall onto 3 Vietnam provinces,” Tuoi Tre, Tue, 05 Jan 2016. http://www.sott.net/article/309800-3-mysterious-spheres-fall-onto-3-Vietnam-provinces
Absorber lining is an important part of an indoor antenna measurement chamber design. During the design phase different absorber types are selected for minimizing the expected reflection from given locations in the chamber. By the time of installation, these absorbers have already been measured as part of the production quality control. The question however arises if after installation, these absorbers still meet the requirements of the design. The free-space-VSWR [1] measurement technique is a method to assess the overall reflectivity of the chamber at a certain location, i.e. quiet-zone reflectivity, but cannot be easily limited to measure the reflectivity of a single wall. In this work the RCS technique [2] is revised. The reflection of the wall is measured using a quasi-monostatic RCS setup which is mounted on a linear sliding system. The linear sliding system is positioned perpendicular to the wall. After measuring at several positions the measurement results are shifted in distance such that the reference target or wall add coherently and clutter or other walls destructively. Using this technique it will be shown that the reflectivity of an absorber-lined wall can be determined during installation where not all walls or floor have been covered yet. [1] J. Appel-Hansen, “Reflectivity level of radio anechoic chambers,” IEEE Trans. Antennas Propag., vol. 21, no. 4, pp. 490–498, Jul. 1973. [2] G. Cottard and Y. Arien, “Anechoic Chamber Measurement Improvement,” Microw. J., no. March, 2006.
The bi-polar scanning proposed by Rahmat-Samii et al. in [1, 2] is particularly attractive for its mechanical characteristics. The antenna under test (AUT) rotates axially, whereas the probe is attached to the end of an arm which rotates around an axis parallel to the AUT one. This allows the collection of the NF data on a grid of concentric rings and radial arcs. Such a scanning maintains all the advantages of the plane-polar one while providing a compact, simple and cost-effective mem. In fact, only rotational motions are required and this is convenient since rotating tables are more accurate than linear positioners. Moreover, being the arm fixed at one point and the probe attached at its end, the bending is constant and this allows one to hold the planarity. An efficient probe compensated NF–FF transformation with bi-polar scanning requiring a minimum number of NF data has been developed in [3] by applying the nonredundant sampling representations of electromagnetic (EM) fields [4, 5] to the voltage measured by the scanning probe and assuming the AUT as enclosed in an oblate ellipsoid. Thus, the plane-rectangular data needed by the classical NF–FF transformation [6] can be efficiently recovered from the nonredundant bi-polar samples by means of an optimal sampling interpolation algorithm. It is so possible to significantly reduce the number of required NF data and related measurement time without losing the efficiency of the previous approaches [1, 2]. Goal of this work is just the experimental validation of the nonredundant NF–FF transformation with bi-polar scanning [3], which will be carried out at the Antenna Characterization Lab of the University of Salerno. [1] L.I. Williams, Y. Rahmat-Samii, and R.G. Yaccarino, “The bi-polar planar near-field measurement technique, Part I: implementation and measurement comparisons,” IEEE Trans. Antennas Prop., vol. 42, pp. 184-195, Feb. 1994. [2] R.G. Yaccarino, Y. Rahmat-Samii, and L.I. Williams, “The bi-polar near-field measurement technique, Part II: NF to FF transformation and holographic methods,” IEEE Trans. Antennas Prop., vol. 42, pp. 196-204, Feb. 1994. [3] F. D’Agostino, C. Gennarelli, G. Riccio, and C. Savarese, “Data reduction in the NF-FF transformation with bi-polar scanning,” Microw. Optic. Technol. Lett., vol. 36, pp. 32-36, Jan. 2003. [4] O.M. Bucci, C. Gennarelli, and C. Savarese, “Representation of electromagnetic fields over arbitrary surfaces by a finite and nonredundant number of samples,” IEEE Trans. Antennas Prop., vol. 46, pp. 351-359, March 1998. [5] O.M. Bucci and C. Gennarelli, “Application of nonredundant sampling representations of electromagnetic fields to NF-FF transformation techniques,” Int. Jour. Antennas Prop., vol. 2012, ID 319856, 14 pages. [6] E.B. Joy, W.M. Leach, G.P. Rodrigue, and D.T. Paris, “Applications of probe-compensated near-field measurements,” IEEE Trans. Antennas Prop., vol. AP-26, pp. 379-389, May 1978.
BIANCHA (BIstatic ANechoic CHAmber) is a singular facility located at the premises of the National Institute for Aerospace Technology (INTA), Spain, and was devised to perform a wide variety of electromagnetic tests and to research into innovative measurement techniques that may need high positioning accuracy. With this facility, both monostatic and bistatic tests can be performed, providing capability for a variety of electromagnetic measurements, such as the electromagnetic characterization of a material, the extraction of the bistatic radar cross section (RCS) of a target, near-field antenna measurements or material absorption measurements by replicating the NRL arch system. BIANCHA consists of two elevated scanning arms holding two antenna probes. While one scanning arm sweeps from one horizon to the other, the second scanning arm is mounted on the azimuth turntable. As a result, BIANCHA provides capability to perform measurements at any combination of angles, establishing a bistatic, spherical field scanner. In this regard, it is worth noting that in the last years, a renewed interest has arisen in bistatic radar. Some of the main reasons behind this renaissance are the recent advances in passive radar systems added to the advantages that bistatic radar can offer to detect stealth platforms. On the other hand, with the aim of developing new aeronautic materials with desired specifications, research on the electromagnetic properties of materials have also attracted much attention, demanding engineers and scientists to assess how these materials may affect the radar response of a target. Consequently, this paper introduces BIANCHA and demonstrates its applicability for these purposes by presenting results of different tests for different applications: a bistatic scattering analysis of scaled aircraft targets and the extraction of the electromagnetic properties of composite materials utilized in an actual aeronautical platform.
Finding the monostatic radar cross section (RCS) of a structure using computational electromagnetics (CEM) is a challenging task, particularly when the structure is large in terms of wavelengths. Such structures are challenging due to the large computational requirements, often combined with high accuracy demands and/or complicated geometry. Previously, these challenges have resulted in algorithms that either relax the accuracy requirements by using asymptotic methods or, if full-wave methods are used, require extreme runtimes even on very large computing clusters. For full-wave methods based on an integral equation formulation, such as Method of Moments (MoM), the reason for the large computational requirements can be found in the O(f^6) computational time scaling of monostatic RCS, where f is the frequency. Acceleration algorithms such as the Multi-Level Fast Multipole Method (MLFMM) reduce this to O(C(f,v) f^2 log f), where C(f,v) is the number of iterations required for convergence of an iterative solver, and v is the number of incident angles. Unfortunately, in most state-of-the-art implementations of monostatic RCS, C(f,v) is very large, meaning that in practice MoM is preferred to avoid an iterative solver. In this paper, we describe a range of efforts towards developing an efficient algorithm for large-scale monostatic RCS, in particular for structures that are too large to handle for MoM. These efforts include an efficient discretization based on higher-order basis functions and quadrilateral meshing of the structure, an MLFMM implementation focused on keeping memory requirements low, and a highly efficient block Krylov solver. The efficient higher-order discretization has already proven its worth for scattering problems, and the paper will demonstrate how its advantages over traditional RWG discretizations make it perfectly suited for RCS computation. In particular, combining the low amount of unknowns with a strong preconditioner allows rapid convergence of the iterative solver. The use of a low-memory MLFMM implementation, tailored for higher-order basis functions, means that problems of unprecedented size can be handled even on ordinary workstations, i.e., without resorting to expensive computing clusters. Finally, recent work on block Krylov solvers, along with interpolation algorithms for linear systems with a large amount of right-hand sides and efficient stopping criteria, allows a short computing time by significantly reducing the number of iterations.