1 Вырез съемки RCD100 Аэросъемочные новости Leica Geosystems X. Юбилейная международная научно-техническая конференция: «От снимка к карте: цифровые фотограмметрические технологии» Гаета 2010, Петер Шрайбер

2 Permanent And Consequent Development of Leica Geosystems Airborne Sensors 1.General developments 2.News to Airborne Digital Sensor, ADS80 3.News to Airborne Lidar System, ALS60

3 1. General development: Leica IPAS Freebird

4 IPAS Freebird – cut corners, not quality User benefits in airborne mission Improves flight economy for sensor missions up to 25% Allow sharper turns between the flight lines – does not require continuous lock of satellites Deeply coupled GNSS-IMU technology saves time several minutes per turn

5 GNSS-IMU processing The basis for accurate image georeferencing GrafNav GNSS trajectory processing Continuous lock of 5 or more satellites is required IPAS Pro GNSS-IMU blending IPAS TC Tightly Coupled GNSS-IMU processing using GNSS raw measurements

6 IPAS Freebird – cut corners, not quality User benefits – data processing Does not require the separate step of GNSS trajectory processing GNSS-IMU post processing is simplified and faster Precise Point Positioning – solutions without GNSS base station data

7 2. News to ADS80 Airborne Digital Sensor

8 Leica ADS80 CCD layout in SH81 and SH82 focal plate SH81 SH82

9 Leica ADS80 Staggered Line Processing Pixel Across Swath in Nadir PAV80 ADS80 Productivity Increase of up to 100% Effective pixels across track Remember: UCX Pan/MS ratio 1:3 DMC Pan/MS ratio 1:4 ADS Pan/MS ratio 1:2 User Benefit: Fly twice as high with same GSD and image quality Huge productivity increase for orthophoto production Best pansharpening ratio on the market

10 Application of staggered CCD line High resolution resampling of overlapping pixels Final Image pixel raster on ground Staggered CCD line GSD 1 / 2 GSD Area of 1 / 2 GSD For high panchromatic resolution with the ADS40 the area of 1 / 2 GSD is computed from 4 different recordings. That is, each recording takes place at 2 locations in each staggered CCD. To achieve this: The readout rate is at 1 / 2 GSD in flight direction 1 / 2 GSD offset across track is obtained with staggered CCD CCD Recording Location CCD 2 1 Pixel

11 ADS80 – Driving Productivity in Imaging Pixel HighRes Mode! 1000m AGL, 10cm GSD2000m AGL, 10cm GSD

12 ADS80 - Driving Productivity in Imaging Standard and HighRes Mode brings Flexibility

13 Example of staggered CCD line (2)

14 MM40 Embedded IPAS20 with GNSS High data throughput of 130 MB/sec Radiometric resolution of compressed data 10-bit and 12-bit, Recording interval 1 ms Data modes: ADS80 data format, raw data, compressed Leica ADS80 – Consistent Technical Performance Control Unit CU80 and MM80 Highly reliable flash disk technology 960 GB capacity per MM80 pair Weight 2.5 kg

3. News to ALS60 Airborne Lidar System

16 Typical LIDAR technology implementation Develop lat/lon/el of points on ground based on: Aircraft position (lat/lon/el) Aircraft orientation (roll/pitch/heading) Scan angle Round-trip propagation time of laser pulse Atmospherics Raw data recorded in air (system) and on ground (DGPS base station) Recorded data post-processed on ground Waveform analysis concerns attributes of the range measurement Time or distance Intensity

17 Footprint Return waveform is generated by all reflective surfaces within the laser footprint LIDAR waveform how is it created? Multiple return pulses are generated as the laser pulse hits various levels in the forest canopy, creating in total a complete return waveform Waveform measurement is a natural extension of the conventional discrete-return + intensity measurement process

18 Laser Footprint Start Pulse Detector Signal T 1, I 1 T n, I n Full Waveform Digitization (FWD) basic concept

19 What is Full Waveform Digitization? capturing the complete return, not just the peaks Conventional discrete return electronics capture only the exact time of the peaks of independently- recognized return pulses Peak intensity is also measured In FWD systems, the entire return signal is measured, allowing capture of subtle deviations in the shape of the reflected as compared to the shape of the outbound laser pulse

20 Some points about FWD Intensities must be digitized at <2 ns intervals to minimize aliasing, though 1 ns more common 1 ns in time represents 0.15 m in range (i.e., elevation) Signal amplitude at each interval typically digitized at 8-bit resolution (i.e., one byte) Therefore, 256 additional bytes of waveform data needed to digitize the return waveform from a 38.4 meter-tall 1 ns intervals Range data is still be measured independently to achieve typical 1.5 cm (i.e., 100 ps) range resolution

21 Operating envelope max waveform rate versus slant range At pulse rates below 120 kHz, waveforms captured at laser pulse rate At pulse rates above 120 kHz, waveforms capture for every other pulse, up to 200 kHz (150 kHz for ALS50-II)

22 Thank You! Спасибо!