We introduce a new complexity measure for cocomparability graphs of posets or in other words, intersection graphs of piecewise linear functions, the bend number. We prove that cocomparability graphs of bounded bend number are not too plentiful and give two hierarchies of classes of cocomparability graphs, depending on whether the piecewise linear functions are restricted to slopes of ±1 (diagonal case) or not (general case). These hierarchies give a gradation between permutation graphs and cocomparability graphs.

The quantification of wet antenna attenuation (WAA) represents one of the major uncertainties in rainfall retrieval from commercial microwave links (CMLs). We propose identifying WAA distribution and upper limits based on rainfall climatology without the need for nearby rainfall observations. The quantified contributions of antenna wetting due to total loss are derived from 2 years of data collected from eight short (48-497 m) CMLs operating at frequencies of 37.3-39.2 GHz within the cellular backhaul. More specifically, the complementary cumulative distribution functions of measured attenuation are compared with theoretical ones calculated from rainfall data from local rain gauges. The results show that WAA reaches 1.5-2.0 dB and dominates over path attenuation during light rainfalls (R <; 2 mm/h). WAA can, however, reach 2.8-5.3 dB during heavy rainfalls and maximal WAA observed during extreme rainfalls (R ≈ 70-130 mm/h) is between 6-9 dB. The constant value of WAA used in some previous studies may, therefore, lead to a significant overestimation of peak rainfalls retrieved from CMLs.