A system and method for detecting concealed weapons using ultrawideband radar detects weapons based on circumference resonance that are characteristic of reflections for cylindrical or conic portions of a type of weapon, and based on barrel length resonances that are characteristic of barrel lengths of the type of weapon. The circumference resonances are detected using ultrawideband radar in the Mie scattering region based on a range of weapons' characteristic radii to ultrawideband wavelengths. The barrel length resonances are detected using ultrahigh frequency radar in the Mie scattering region based on range of weapons' characteristic lengths to ultrahigh frequency wavelengths. Circumferential resonance patterns and length resonance patterns are combined to provide improved weapon type identification without relying on orientation of the concealed weapons. An array of ultrawideband radar apparatus may be configured to provide synthetic aperture radar imaging of a target area.