Statistical Characteristics Measurement Research On Millimeter Wave Radiation Of Typical Coating Materials

Passive millimeter wave(MMW)radiation detection,as a new detection mode,is gradually developing into a supplement to other detection modes.Coating material,duo to its little influence on target and easy to coat,is widely applied which present a challenge for detection.Focused on passive MMW detection of typical targets and to make clear radiation characteristics,this paper analyzes statistical characteristics of different coating materials and then carries out lots of statistical measurement experiments,which provide foundation for passive MMW detection.Moreover,this paper presents a threshold method separating 1/f-noise in band pass signal.The main work is shown as follows:Radiometer is a high sensitivity receiver receiving nature thermal radiation and its performance has directly effect on statistical characteristics of signals.Therefore,this paper studies on the effect of system noises and transfer characteristics of radiometer tunnel on statistical characteristics of radiation.To learn the relationship of tunnel transfer function and signal statistical characteristics,it establishes transfer functions of different main radiometer functional modules and analyses statistical characteristics changes between input and output signal.System noises mainly come from the electronic devices and the research aimed at it includes several aspects,such as main system noises types,the effects on statistical characteristics,and the elimination of flicker noise(1/f-noise).Besides,experiments observing noise source are carried out to obtain the power of 1/f-noise in MMW radiometer.Based on system noises and tunnel transfer function,this paper analyzes statistical characteristic of passive MMW radiation concretely,including digital characteristics,statistical distribution,stationarity and ergodicity and power spectrum.To make clear the radiation of typical materials,including smooth aluminum plate,black body,antiseptic,absorbing and antiseptic-absorbing materials,then lots of different coating materials observation experiments are carried out at outside in cloudless condition.Meanwhile,this paper makes comparisons of statistical characteristics between different materials,which lay the foundation for radiometer detection and classification of typical targets.