The passive orientation of IRST is a dynamic triangle measurement. For the fixed target, the orientation error can be minimized by multiple measurements and the least squares(LS) method.

IRST的被动定位实质上是一个动态三角测量法，对于固定目标，可以利用多次测量和最小二乘法降低定位误差。

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In the future Navisens hopes to be able to display that orientation in the form of, perhaps, a small green triangle - which has obvious appeal to potential advertisers seeking out ways to know how, where and when potential customers are almost face-to-face with their products.

BBC: Technology that works behind closed doors