Methodology for designing millimeter-wave simulants with low loss powders

A method of producing a simulant mixture having a simulant reflectivity to match a threat reflectivity R of a target threat, comprising:

• measuring the threat reflectivity R of the target threat;
• converting a value of the threat reflectivity R to a value of a threat dielectric constant ε′, by using the value of the threat reflectivity R in a reduced reflectivity equation expressed as (1−R)ε′−2(1+R)√{square root over (ε′)}+(1−R)=0 and solving for the value of the threat dielectric constant ε′, wherein the reduced reflectivity equation corresponds to a graph of a curved solution space representing ε′ and ε″ pairs of the threat reflectivity R reduced by assigning a value of zero to threat loss factor ε″ consistent with an intercept of an x-axis of the graph;
• assigning the value of the threat dielectric constant ε′ to a variable εmixture in a Landau-Lifshitz-Looyenga (LLL) mixture equation;
• selecting, as first two simulant ingredients of the simulant mixture as represented by the LLL mixture equation, an equal percent by weight (% w/w) of stearic acid melted and petrolatum melted, thereby constraining the LLL mixture equation;
• selecting specific % w/w for the first two simulant ingredients corresponding to a morphology for the simulant mixture to match the target threat, thereby constraining the LLL mixture equation by selecting a corresponding one of a set of percents by weight according to:
• 17% w/w stearic acid melted and 17% w/w petrolatum melted for wet sand-like morphology,
• 20% w/w stearic acid melted and 20% w/w petrolatum melted for putty morphology, or
• 23% w/w stearic acid melted and 23% w/w petrolatum melted for paste morphology;
• selecting additional simulant ingredients from the group consisting of:
• stearic acid powdered, low loss dielectric filler powder of dielectric constant value 7, low loss dielectric filler powder of dielectric constant value 12, and low loss dielectric filler powder of dielectric constant value 27;
• the additional simulant ingredients being essentially lossless based on each of their respective ε″<0.0007, thereby constraining the LLL mixture equation to this set of potential additional simulant ingredients;
• determining a percentage by weight for each of the additional simulant ingredients that are to be mixed with the first two simulant ingredients, by solving the LLL mixture equation constrained by assigning the variable εmixture along with characteristics of the first two simulant ingredients and selection of additional simulant ingredients, to obtain corresponding respective mass fractions indicating respective % w/w of each of the additional simulant ingredients to form the simulant mixture in satisfaction of the LLL mixture equation;
• and
• mixing the corresponding additional simulant ingredients with the first two simulant ingredients, according to values for the additional simulant ingredients as indicated by the LLL mixture equation as constrained by the morphology established by the first two simulant ingredients, to produce the simulant mixture expressing the simulant reflectivity matching the threat reflectivity R of the target threat to be simulated.