ENVISAT RA2/MWR Product Handbook

Abstract

RA2/MWR Products User Guide

1.1 How To Choose RA-2/MWR Data Products

1.1.1 Geophysical Measurements

1.1.2 Scientific Background

Oceanographic Applications

Ice and Sea-Ice Applications

Land Applications

1.1.3 Principles Of Measurement

1.1.4 Geophysical Coverage

1.1.5 Peculiarities of RA2

1.1.6 Peculiarities of MWR

1.1.7 Summary of Applications vs. Products

1.2 How to use RA-2/MWR data

1.2.1 Software Tools

1.2.1.1 General tools

1.2.1.2 EnviView

1.3 Further reading

RA2/MWR Products andAlgorithms

2.1 Introduction

2.2 Organisation of Products

2.3 Definitions and Conventions

2.4 Products Evolution History

2.4.1 L1B IPF upgrades

2.4.2 L2 IPF upgrades

2.4.3 L2 CMA upgrades

2.5 Level 0 products

2.5.1 RA-2 Level 0 products

2.5.1.1 Definition

2.5.1.2 Structure

2.5.1.3 Packet Header

2.5.1.4 Packet Data Field

2.5.2 MWR Level 0 products

2.5.2.1 Definition

2.5.2.2 Structure

2.5.2.3 Packet Header

2.5.2.4 Packet Data Field

2.6 RA-2/MWR Level 1b Products and Algorithms

2.6.1 RA-2 Level 1b algorithms

2.6.1.1 Level 0 data decoding

2.6.1.2 PTR Data Processing

2.6.1.3 IF Shape Correction

2.6.1.4 AGC Calibration

2.6.1.5 Window Time Reference Extraction

2.6.1.6 Orbit Data Generation and Datation Correction

2.6.1.7 Level 1b data formatting

2.6.2 MWR Level 1b algorithms

2.6.2.1 Level 0 data extraction and decoding

2.6.2.2 Gain Processing and Offset Temperature Evaluation

2.6.2.3 Antenna Temperature Retrieval

2.6.2.4 Brightness Temperature Evaluation

2.6.2.5 Antenna axis registration

2.6.2.6 Level 1b Data Formatting

2.6.3 RA-2/MWR Level 1b product

2.6.3.1 Definition

2.6.3.2 Structure

2.6.3.3 RA-2/MWR Level 1b SPH

2.6.3.4 Level 1b RA2 MDS

2.6.3.5 Level 1b RA2 individual echoes waveforms MDS

2.6.3.6 Level 1b PTR MDS

2.6.3.7 Level 1b MWR MDS

2.7 RA-2/MWR Level 2 Products And Algorithms

2.7.1 RA-2 Level 2 Algorithms

2.7.1.1 Ocean retracking algorithm

Applicability

Accuracy

References

2.7.1.2 Ice2 retracking algorithm

Applicability

Accuracy

References

2.7.1.3 Level 2 Ice Algorithms : General

2.7.1.4 Level 2 Ice Algorithms : Retracking

2.7.1.4.1 Pre-processing

2.7.1.4.2 OCOG Retracking

The OCOG Retracking Algorithm

2.7.1.4.3 Sea-Ice Retracking

The Sea-ice Retracking Algorithm

2.7.1.5 Level 2 Ice Algorithms : Slope Correction

2.7.1.5.1 Co-ordinate Conversion

Accuracy

2.7.1.5.2 Echo Direction

Accuracy

2.7.1.5.3 Elevation Calculation

Accuracy

2.7.1.6 Level 2 Ice Algorithms : Delta Doppler Correction

Accuracy

2.7.1.7 Doppler correction

2.7.1.8 ECMWF model derived wet and dry tropospheric corrections, uand v components of the wind vector, and surface pressure

Applicability

Accuracy

Reference

2.7.1.9 Inverted barometer correction algorithm

Applicability

Accuracy

References

2.7.1.10 Combined atmospheric correction from MOG2D and IB

Applicability

Reference

2.7.1.11 MWR wet tropospheric correction

Applicability

Accuracy

Reference

2.7.1.12 Sea state bias

Applicability

Accuracy

References

2.7.1.13 RA-2 ionospheric correction

Applicability

Accuracy

Reference

2.7.1.14 DORIS ionospheric correction

Applicability

Accuracy

Reference

2.7.1.15 BENT model ionospheric correction

2.7.1.16 GIM Ionospheric correction

Applicability

Reference

2.7.1.17 Atmospheric attenuation correction

Applicability

Accuracy

Reference

2.7.1.18 Ku-band rain attenuation

Applicability

Accuracy

Reference

2.7.1.19 Squared Off nadir angle of the satellite computed from platformdata

Applicability

Accuracy

Reference

2.7.1.20 Mean sea surface height

Applicability

Accuracy

Reference

2.7.1.21 Geoid height

Applicability

Accuracy

Reference

2.7.1.22 Ocean depth/land elevation

Applicability

Accuracy

Reference

2.7.1.23 Total geocentric ocean tide height (solution 1)

Applicability

Accuracy

Reference

2.7.1.24 Total geocentric ocean tide height (solution 2)

Applicability

Accuracy

References

2.7.1.25 Solid earth tide height and long period tide height

Applicability

Accuracy

References

2.7.1.26 Tidal loading height according to ocean tide solution 1

Applicability

Accuracy

References

2.7.1.27 Tidal loading height according to ocean tide solution 2

Applicability

Accuracy

References

2.7.1.28 Geocentric pole tide height

Applicability

Accuracy

Reference

2.7.1.29 MWR water vapour content

Applicability

Accuracy

Reference

2.7.1.30 MWR liquid water content

Applicability

Accuracy

Reference

2.7.1.31 RA-2 wind speed algorithm

Applicability

Accuracy

Reference

2.7.1.32 Averaged Ku chirp band

2.7.2 RA2/MWR Level 2 Products

2.7.2.1 Definition

2.7.2.2 Structure

2.7.2.3 Level 2 RA2/MWR SPH

2.7.2.4 Level 2 RA2 MDS in FDGDR, IGDR and GDR

2.7.2.5 Level 2 RA2 MDS in FDMAR and IMAR

2.7.2.6 Level 2 MWR MDS

2.7.2.7 Level 2 Averaged Waveforms MDS

2.7.2.8 Level 2 Individual Waveforms MDS

2.8 Specific Topics Related To The RadarAltimeter

2.8.1 Data Packeting

2.8.2 Time Handling And Leap Seconds

2.8.2.1 Leap Second Description

2.8.2.2 Leap second correction

2.8.2.3 Evolution of L1b time stamps during a leap second occurrence

2.8.2.4 Leap_sign

2.8.2.5 Leap_err

2.8.3 Datation

2.8.4 Measurement Reference

2.8.5 Orbit interpolation

2.8.5.1 po_ppforb

2.8.5.2 po_interpol

2.9 RA-2/MWR Auxiliary files

2.9.1 Summary of Auxiliary Data Sets

2.9.2 Level 1b processing

RA2_CON_AX (RA2 Configuration file)

RA2_IFF_AX (RA2 flight IF mask data)

RA2_USO_AX (RA2 USO file)

MWR_SLT_AX (MWR Side Lobes Temperaturefile)

MWR_CHD_AX (MWR Characterisation file)

MWR_CON_AX (MWR Configuration file)

2.9.3 Level 2 processing

RA2_IOC_AX (Model ionospheric coefficients file)

RA2_MSS_AX (Mean Sea Surface)

RA2_SOL_AX (Solar activity data file)

RA2_POL_AX (Pole location position data file)

RA2_PLA_AX (Platform data file)

RA2_SOI_AX (Ocean/Ice 2 configuration systemfile)

RA2_ICT_AX (Ice1/ sea ice Configuration systemfile)

RA2_SSB_AX (Sea State Bias table file)

RA2_DIP_AX (Modified Dip Map file)

RA2_SET_AX (Cartwright Amplitudes file)

RA2_OT1_AX (Coefficient map for the ocean tidecalculation - solution 1)

RA2_OT2_AX (Coefficient map for the ocean tidecalculation - solution 2)

RA2_TLG_AX (Coefficients map for the tidalloading calculation - solution 1)

RA2_TLD_AX (Coefficients map for the tidalloading calculation - solution 2)

RA2_GEO_AX (Geoid height map)

AUX_DEM_AX (Ocean depth/land elevation map)

RA2_SL1_AX (RA-2 slope model for Greenlanddata file)

RA2_SL2_AX (RA-2 slope model for Antarcticadata file)

MWR_LSF_AX (Land/Sea mask map)

RA2_MET_AX (Altitude of meteorological gridpoints)

AUX_ECF_AX and AUX_ECA_AX (ECMWFforecast and analysis meteorological data files)

2.9.4 Common Auxiliary Data Sets

RA2_CST_AX (RA2/MWR Constants file)

RA2_CHD_AX (RA2 Characterisation file)

DOR_POR_AX, DOR_VOR_AX andAUX_FRO_AX (restituted Orbit State vector files)

2.10 Latency, Throughput And Data Volume.

2.10.1 Product Latency

2.10.2 Product size

2.11 Characterisation And Calibration

2.12 Data Handling Cookbook

2.12.1 Hints And Algorithms For Product Use

RA-2 and MWR Instruments

3.1 RA-2 Instrument Description

3.2 RA-2 Instrument Characteristics andPerformance

3.2.1 Pre-flight Characteristics and expected performance

3.2.1.1 Chirp Generator

3.2.1.2 Frequency Generation and Conversion Unit

3.2.1.3 Transmitter

3.2.1.4 Antenna

3.2.1.5 Microwave Receiver

3.2.1.6 Digital Processing Subassembly Unit

3.2.1.7 Low Voltage Power Supply and Instrument Control Unit

3.2.2 In-flight Performance verification

3.3 MWR Instrument Description

3.4 MWR Instrument Characteristics andPerformance

3.4.1 Pre-flight Characteristics and expected performance

3.4.1.1 Radiometric Receiving System

3.4.1.2 Antenna

3.4.1.2.1 Measurement Feed-Horns

3.4.1.2.2 Measurement Antenna

3.4.1.2.3 Sky-Horn Antenna

3.4.1.3 Radio Frequency Front End

3.4.1.4 Intermediate Frequency (IF) and Video

3.4.1.5 Instrument Operational Mode

3.4.1.6 Instrument Data Characteristics and Data Rate

3.4.1.7 Instrument Improvements

3.4.2 In-flight performance verification

Frequently Asked Questions

4.1 RA-2 Instrument

4.2 MWR Instrument

4.3 Main RA-2 Level 1b algorithms

4.4 Main MWR Level 1b algorithms

4.5 Main RA-2 Level 2 Algorithms (Non-Ocean)

Glossary

5.1 Acronyms And Abbrieviations

RA2/MWR Data Formats Products

Credits