A systematic approach to the Planck LFI end-to-end test and its application to the DPC Level 1 pipeline

The Level 1 of the Planck LFI Data Processing Centre (DPC) is devoted to the handling of the scientific and housekeeping telemetry. It is a critical component of the Planck ground segment which has to strictly commit to the project schedule to be ready for the launch and flight operations. In order to guarantee the quality necessary to achieve the objectives of the Planck mission, the design and development of the Level 1 software has followed the ESA Software Engineering Standards. A fundamental step in the software life cycle is the Verification and Validation of the software. The purpose of this work is to show an example of procedures, test development and analysis successfully applied to a key software project of an ESA mission. We present the end-to-end validation tests performed on the Level 1 of the LFI-DPC, by detailing the methods used and the results obtained. Different approaches have been used to test the scientific and housekeeping data processing. Scientific data processing has been tested by injecting signals with known properties directly into the acquisition electronics, in order to generate a test dataset of real telemetry data and reproduce as much as possible nominal conditions. For the HK telemetry processing, validation software have been developed to inject known parameter values into a set of real housekeeping packets and perform a comparison with the corresponding timelines generated by the Level 1. With the proposed validation and verification procedure, where the on-board and ground processing are viewed as a single pipeline, we demonstrated that the scientific and housekeeping processing of the Planck-LFI raw data is correct and meets the project requirements.Comment: 20 pages, 7 figures; this paper is part of the Prelaunch status LFI papers published on JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/jins

SP-613 - SEASAR 2006

ABSTRACT Liaodong bay in Bohai Sea is the main China offshore sea ice region, and SAR images can be used in the operational sea ice monitoring of this area. In this paper, we collected time series of ENVISAT ASAR imageries covering Liaodong bay and analyzed their backscattering distributions and texture features. From the differences between the open water and sea ice in the mean feature images, we extracted the open water. Then the area of sea ice can be obtained. Three SAR images of different time are selected to describe the changes of sea ice extent at different time. Then the results are compared with those obtained from synchronous MODIS images, and the results prove the validation of using SAR images to monitor sea ice extent and its evolution in Liaodong bay

SP-613 - SEASAR 2006

ABSTRACT Large internal solitary waves with long crest are often observed in the northern of South China Sea by using remote sensing imagery. The wide swath remote sensing images such as RADARSAT ScanSAR, ENVISAT ASAR WSM and MODIS can cover a large area and observe several internal solitary wave packets in one scene. And these images have higher temporal resolution. So we can combine several images to monitor internal wave's evolution. In this paper internal waves propagation features are researched by synergy ENVISAT, RADARSAT, MODIS, TM images. The CTD data of internal solitary wave in South China Sea also validate our conclusion

SP-582 Second MSG RAO Workshop

ABSTRACT In this study, five of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) channels are inter-calibrated with similar channels on MODerate resolution Imaging Spectroradiometer (MODIS) and Geostationary Operational Environmental Satellite (GOES)-12/ Visible Infrared Scanner (VIRS). A ray-matching technique combines pairs of pixel sets from each satellite at almost the same times from nearly the same angles. The MODIS and VIRS derived SEVIRI 0.635 and 0.810µm gains indicate to have increased since launch. Monthly gains computed from April to August of 2004 establish that the SEVIRI visible channels are quite stable during this time period. The SEVIRI 3.9µm temperature is colder than the corresponding MODIS and GOES-12 temperatures. However the SEVIRI 11.7µm temperatures are warmer. 1

Level 1 on-ground telemetry handling in Planck-LFI

The Planck Low Frequency Instrument (LFI) will observe the Cosmic Microwave Background (CMB) by covering the frequency range 30-70 GHz in three bands. The primary instrument data source are the temperature samples acquired by the 22 radiometers mounted on the Planck focal plane. Such samples represent the scientific data of LFI. In addition, the LFI instrument generates the so called housekeeping data by sampling regularly the on-board sensors and registers. The housekeeping data provides information on the overall health status of the instrument and on the scientific data quality. The scientific and housekeeping data are collected on-board into telemetry packets compliant with the ESA Packet Telemetry standards. They represent the primary input to the first processing level of the LFI Data Processing Centre. In this work we show the software systems which build the LFI Level 1. A real-time assessment system, based on the ESA SCOS 2000 generic mission control system, has the main purpose of monitoring the housekeeping parameters of LFI and detect possible anomalies. A telemetry handler system processes the housekeeping and scientific telemetry of LFI, generating timelines for each acquisition chain and each housekeeping parameter. Such timelines represent the main input to the subsequent processing levels of the LFI DPC. A telemetry quick-look system allows the real-time visualization of the LFI scientific and housekeeping data, by also calculating quick statistical functions and fast Fourier transforms. The LFI Level 1 has been designed to support all the mission phases, from the instrument ground tests and calibration to the flight operations, and developed according to the ESA engineering standards