An electronic device, comprising: a radar system , implemented at least partially in hardware, configured to: provide a radar field ; sense reflections from an input device in the radar field to control applications on the electronic device ; analyze the reflections from the input device in the radar field ; and provide, based on the analysis of the reflections, radar data; one or more computer processors ; and one or more computer-readable media having instructions stored thereon that, responsive to execution by the one or more computer processors , implement a radar-signature manager configured to: detect, based on a first subset of the radar data, a radar signature of a radar-image shaper of the input device in the radar field , the radar-image shaper being a component of the input device producing a known radar signature when illuminated by the radar field ; compare the detected radar signature to a benchmark radar signature that corresponds to a characteristic disposition of the radar-image shaper ; determine, based on the comparison, that the detected radar signature matches the benchmark radar signature; and responsive to the determination that the detected radar signature matches the benchmark radar signature, determine, based on the characteristic disposition of the radar-image shaper that corresponds to the matched benchmark radar signature, a characteristic disposition of the input device in the radar field . a radar system , implemented at least partially in hardware, configured to: provide a radar field ; sense reflections from an input device in the radar field to control applications on the electronic device ; analyze the reflections from the input device in the radar field ; and provide, based on the analysis of the reflections, radar data; provide a radar field ; sense reflections from an input device in the radar field to control applications on the electronic device ; analyze the reflections from the input device in the radar field ; and provide, based on the analysis of the reflections, radar data; one or more computer processors ; and one or more computer-readable media having instructions stored thereon that, responsive to execution by the one or more computer processors , implement a radar-signature manager configured to: detect, based on a first subset of the radar data, a radar signature of a radar-image shaper of the input device in the radar field , the radar-image shaper being a component of the input device producing a known radar signature when illuminated by the radar field ; compare the detected radar signature to a benchmark radar signature that corresponds to a characteristic disposition of the radar-image shaper ; determine, based on the comparison, that the detected radar signature matches the benchmark radar signature; and responsive to the determination that the detected radar signature matches the benchmark radar signature, determine, based on the characteristic disposition of the radar-image shaper that corresponds to the matched benchmark radar signature, a characteristic disposition of the input device in the radar field . detect, based on a first subset of the radar data, a radar signature of a radar-image shaper of the input device in the radar field , the radar-image shaper being a component of the input device producing a known radar signature when illuminated by the radar field ; compare the detected radar signature to a benchmark radar signature that corresponds to a characteristic disposition of the radar-image shaper ; determine, based on the comparison, that the detected radar signature matches the benchmark radar signature; and responsive to the determination that the detected radar signature matches the benchmark radar signature, determine, based on the characteristic disposition of the radar-image shaper that corresponds to the matched benchmark radar signature, a characteristic disposition of the input device in the radar field . <EOS>