Apparatus, systems, and methods are described that implement techniques for estimating a relative rotation between a first complex signal and a second complex signal. The resolution is based on finding the least square fit of the mass ratio coefficients at each locus to come closest to the quantitative allele peak data. Such wireless sensor node group affiliation information as corresponds to other wireless sensor nodes might be received, for example, directly from that other wireless sensor node andor via an intermediary wireless sensor node that acts to forward such information from the other wireless sensor node. The focused light is guided by a laser light guiding component disposed in a diffusive reflection tube.