Research On Lifeform-identification Technology For Detecting The Wounded

Detecting the wounded means to find out whether there is any wounded soldier alive under the debris by using the equipment of detecting the wounded which can locate the wounded and save time for first aid to them.The equipment of detecting the wounded is developed by the technology of Radar Non-contact Life-parameter Detecting (RNLD). Without any electrode, transducer, cable, etc, life-parameters such as breathing and heartbeat can be sensed at a certain distance or behind certain substances. The equipment uses microwave beams to illuminate the human body and the surface movement caused by physical activity of human body modulates the return microwave beams. Therefore some parameters of the return signal, such as the frequency and the phase will bechanged. If these changes can be detected, the life parameters will beextracted.The study of this paper comes from the tenth five military appointed project. The laboratorial equipment S2000?I has been developed by the research group. During the equipment works outside, it is the key to accurately judge whether there exists lifeforms under the debris. Because the detected signals are complicated, including human life-parameter signals, environmental interference, radar sub-lobe clutter and noise of the whole system, it greatly reduces the signal-to-noise ratio (SNR) of the life-parameter signals and makes it difficult to identify the lifeforms. Therefore, the main task of this paper is to identify lifeforms effectively and make the equipment S2000?I into practice.According to these problems mentioned above, following study and experiments have been performed in the paper: 1 .Analysing life-parameter signals under different conditions in time domain and frequency domain; 2. Studying the eigenvalue of human life-parameter signals and the methods to extract them. 3. Providing a series of methods of lifeform identification. 4. Developing a software system for the wounded detecting equipment.During the research work, two detecting system 36 GHz and 1.5GHz are selected respectively to obtain life-parameter signals, which are amplified and filtered in the signal preprocessor. Then the signals are conversed by A/D device and passed to the computer. By analyzing the results of the eigenvalue of life-parameter signals, several signal-processing methods are selected to build life identification algorithm. The sampling and display of the signal are realized by a component named Tvichw32 under Windowsoperating system. Under the software of Matlab life-parameter signals are processed and analyzed in both time and frequency domain and then life identification algorithm is developed. Finally the friendly interface of the application is developed with Delphi which has a visible programming environment.The main results that have been accomplished in the paper are listed below: 1. Accumulated lots of experimental data of life-parameter signals with the equipment of detecting the wounded. 2. Provided a method of frequency domain signal integration based on FFT to detect non-contact life-parameter signals. 3. Built up an algorithm of lifeform identification which was based on the time and the frequency domain analysis of life-parameter signals. 4. Developed an application software of life identification for the wounded detecting equipment system S2000?I.Innovations in the paper are listed below: 1. Provided a new method used to detect non-contact life-parameter signals which was based on FFT frequency domain signal integration. 2. Built up an new algorithm of life identification for Radar Non-contact Life-parameter Detecting and the application software of the wounded detecting lifeform identification is developed.