CHARACTERIZATION OF MLS 1 F NOISE PARAMETERS

Optimal filters provide minimum variance interpolation and smoothing o f noisy data, but the form of the noise power spectrum must be known f or their design. We analyse data from the Microwave Limb Sounder (MLS) experiment onboard the Upper Atmosphere Research Satellite (UARS) to quantify parameters describing the noise spectra. MLS views space as p art of its calibration sequence providing regular samples of the radio meter output. From these samples we determine breakpoint frequencies a t which the spectral power density of the low frequency l/f noise is e qual to that of the white noise. Breakpoint frequencies were in the ra nge from 0.005 to 0.02 Hz for the 90 filter channels of the MLS. A met hod was developed to distinguish between l/f noise and systematic dist urbances caused by cyclic changes in the operating environment as the spacecraft traverses its orbit.