Interpreting directional data from large pitch-roll-heave buoys

摘要: Abstract Surface-following buoys are commonly used to measure directional wave spectra. At each frequency, four parameters can be calculated from the auto- and cross-spectra of pitch, roll heave. It is shown that for many buoys, particularly large data response must taken into account when calculating spread parameter s 1 or related such as r.m.s. angular σ. The detection noise in records discussed, some likely sources identified. These include effects compass tilt. mean direction θ M robust against presence noise, but σ very sensitive it. theoretical results illustrated with U.K. DB1 DB2.