 | Kugler F.A. Pol-InSAR forest height estimation at different frequencies: opportunities and limitations / Deutsches Zentrum für Luft-und Raumfahrt, Institut für Hochfrequenztechnik und Radarsysteme, Oberpfaffenhofen. - Köln: DLR, 2016. - XVIII, 155,98 p.: ill., tab. - (Forschungsbericht; 2016-43). - Res. also Germ. - Bibliogr.: p.122-147 and at the end of the art. - ISSN 1434-8454
Шифр: (Pr 1120/2016-43) 02
|
Abstract ....................................................... IV
Preface ........................................................ VI
Contents ....................................................... VI
List of Symbols and Acronyms .................................. XII
1 Introduction ............................................... 1
1.1 State of the art forest inventories ................... 1
1.1.1 On national level ................................... 1
1.1.2 On enterprise level ................................. 3
1.1.3 State of the art ground measurements ................ 4
1.2 Observation requirements: parameters, temporal and
spatial resolution ......................................... 6
1.2.1 General requirements for a remote sensing based
forest monitoring ................................... 7
1.2.2 Forest management ................................... 7
1.2.3 Forest monitoring on national and global level ...... 8
1.2.4 Disaster monitoring ................................. 9
1.2.5 Forest fires: ...................................... 10
1.2.6 Storm damages ...................................... 10
1.2.7 Forest certification ............................... 10
1.2.8 REDD ............................................... 11
1.2.9 Carbon storage estimation .......................... 11
1.2.10 Other applications ................................. 12
1.2.11 Summary user requirements .......................... 13
2 Forest height: relevance as single parameter .............. 14
2.1 Definition of forest height ............................... 14
2.2 Forest height for stock volume estimation ................. 15
2.3 Forest height for site index evaluation ................... 15
2.4 Forest height for biomass estimation ...................... 15
2.5 Forest height for forest-non-forest mapping ............... 16
2.6 Forest height for forest management ....................... 17
2.7 Forest height for change detection ........................ 17
2.8 Forest height for spatial landscape modelling ............. 17
2.9 Forest height for horizontal structure estimation ......... 17
3 Remote sensing systems and applications ................... 19
3.1 Optical remote sensing .................................... 19
3.1.1 Photogrammetry ..................................... 19
3.1.2 Forest-non-forest .................................. 19
3.1.3 Forest stratification with optical data ............ 20
3.1.4 LAI from optical data .............................. 21
3.1.5 Biomass from optical data .......................... 21
3.2 LIDAR remote sensing ...................................... 21
3.2.1 Small footprint UDAR ............................... 21
3.2.2 Large footprint LIDAR .............................. 22
3.2.3 LIDAR H100 ......................................... 23
3.3 Radar remote sensing ...................................... 24
3.3.1 Forest-non-forest .................................. 26
3.3.2 Forest classification .............................. 26
3.3.3 Forest height ...................................... 26
3.3.3.1 Forest height estimates from DSMs .............. 27
3.3.3.2 Model derived forest height .................... 27
3.3.4 Biomass ............................................ 28
3.3.4.1 Backscatter biomass relations .................. 28
3.3.4.2 Coherence biomass estimation ................... 28
3.3.4.3 Height of the scattering center for biomass
estimation ..................................... 29
3.3.4.4 Height to biomass .............................. 29
3.3.5 Forest structure ................................... 29
3.3.5.1 Structure to biomass ........................... 30
4 SAR principles ............................................ 31
4.1 SAR system characteristics ................................ 31
4.1.1 Acquisition geometry ............................... 31
4.1.2 Spatial resolution ................................. 32
4.1.2.1 Range resolution ............................... 32
4.1.2.2 Azimuth resolution ............................. 33
4.1.3 Effects in SAR images .............................. 34
4.1.3.1 Incidence angle ................................ 34
4.1.3.2 Elevation changes .............................. 35
4.1.3.3 Speckle ........................................ 36
4.1.4 Radiometric resolution ............................. 38
4.1.5 Radar backscattering coefficient ................... 38
4.1.6 Signal to Noise Ratio .............................. 39
4.2 SAR-polarimetry ........................................... 39
4.2.1 Polarimetry basics ................................. 39
4.2.2 Jones vector and scattering matrices ............... 41
4.3 SAR-interferometry ........................................ 44
4.3.1 Interferometrie measurement principle .............. 44
4.3.2 Flat earth ......................................... 46
4.3.3 Phase to height conversion ......................... 47
4.3.4 Coherence .......................................... 48
4.3.5 Coherence and phase statistics ..................... 49
4.3.6 Coherence interpretation ........................... 51
4.3.6.1 Spectral decorrelation calibration ............. 51
4.3.6.2 System induced decorrelation contributions ..... 52
4.3.6.3 Temporal decorrelation ......................... 53
4.4 Pol-InSAR ................................................. 54
4.4.1 Pol-InSAR fundamentals ............................. 54
4.4.2 Coherence region ................................... 55
5 Model based Pol-InSAR parameter estimation ................ 59
5.1 Modelling of volume decorrelation ......................... 59
5.1.1 Exponential vertical backscatter function .......... 60
5.1.2 Modi fications of the vertical backscatter
function ........................................... 61
5.2 The vertical wavenumber ................................... 64
5.3 Pol-InSAR forest height inversion .................... 65
5.3.1 Three stage inversion steps ........................ 65
5.3.1.1 Line fit ....................................... 65
5.3.1.2 Estimation of the underlying ground ............ 66
5.3.1.3 Height inversion ............................... 67
5.3.2 The role of the vertical wavenumber in forest
height inversion ................................... 69
5.3.3 Incoherent multibaseline combination/selection ..... 71
5.4 Temporal decorrelation .................................... 72
5.5 Obtained results .......................................... 74
5.5.1 Pol-InSAR inversion results for different
frequencies and forest types ....................... 75
5.5.2 Extinction ......................................... 78
5.5.3 Change detection ................................... 79
5.6 Dual baseline forest height inversion ..................... 82
5.6.1 Dual baseline forest height inversion accounting
for mmin > 0 ....................................... 83
5.6.2 Dual baseline forest height inversion accounting
for temporal decorrelation in the volume part γTV .. 83
5.6.3 Results dual baseline forest height inversion ...... 84
6 Relevant SAR satellite missions for Pol-InSAR forest
monitoring ................................................ 89
6.1 ALOS, ALOS-2 .............................................. 89
6.1.1 System characteristics ............................. 89
6.1.2 Pros ............................................... 91
6.1.3 Cons ............................................... 91
6.2 TanDEM-X .................................................. 93
6.2.1 System Characteristics ............................. 94
6.2.2 Pros ............................................... 95
6.2.3 Cons ............................................... 95
6.2.4 Summary TanDEM-X ................................... 96
6.2.5 Temporal decorrelation at TanDEM-X monostatic
acquisitions ....................................... 97
7 Conclusions, Outlook and Own Contributions ................ 99
7.1 Conclusions ............................................... 99
7.2 Outlook .................................................. 103
7.2.1 BIOMASS ........................................... 103
7.2.1.1 System Characteristics ........................ 103
7.2.1.2 Pros .......................................... 104
7.2.1.3 Cons .......................................... 104
7.2.2 Tandem-L .......................................... 105
7.2.2.1 System Characteristics ........................ 105
7.2.2.2 Pros .......................................... 106
7.2.2.3 Cons .......................................... 107
7.3 Author's contributions ................................... 107
8 Reviewed papers and author's contribution ................ 110
8.1 Publication I ............................................ 110
8.2 Publication II ........................................... 112
8.3 Publication III .......................................... 114
8.4 Publication IV ........................................... 116
8.5 Publication V ............................................ 118
8.6 Publication VI ........................................... 120
Bibliography .................................................. 122
Appendix I: Publication list .................................. 148
Appendix II: Articles ......................................... 153
|
|
