A system and method for non-invasive and continuous measurement of cardiac chamber volume and derivative parameters including stroke volume, cardiac output and ejection fraction comprising an ultrawideband radar system having a transmitting and receiving antenna for applying ultrawideband radio signals to a target area of a subject's anatomy wherein the receiving antenna collects and transmits signal returns from the target area which are then delivered to a data processing unit, such as an integrated processor or PDA, having software and hardware used to process the signal returns to produce a value for cardiac stroke volume and changes in cardiac stroke volume supporting multiple diagnostic requirements for emergency response and medical personnel whether located in the battlefield, at a disaster site or at a hospital or other treatment facility.