At present, geographic information at the 
regional and local level is mostly collected 
by means of surveys, digitization of existing 
maps and interpretation of aerial photographs 
using analytical instruments such as 
stereoplotters. Although improvements are 
taking place across the board, the methods 
generally remain labor intensive and time 
consuming. 
A viable replacement technology may evolve 
from digital airborne sensors, but so far 
solutions applied to defense requirements are 
either classified or not affordable. 
However, a number of more recent developments 
may indicate the tide is turning here as 
well. These include: 
• Affordable digital cameras are now 
available which produce a digital image 
on a small disk for input into a larger 
system. 
• Airborne synthetic aperture radar (SAR) 
of 6m resolution is being flown 
commercially now by Intera Technologies 
for a number of ground cover and ice 
reconnaissance applications. Higher 
resolution systems (3m) are currently 
under development. 
These systems, built by MacDonald 
Dettwiler, provide an all weather 
day/night data source for many 
applications. A major application in 
Canada is in the area of monitoring ice 
conditions in the Canadian Arctic. 
Airborne SAR image data is used as a 
primary source for the Ice Data 
Integration and Analysis System (IDIAS) 
operated by the Atmospheric and 
Environmental Services Department in 
Canada. • 
• A prototype submeter resolution 
Multispectral Electro-optical Imaging 
Sensor (MEIS) has been developed by 
MacDonald Dettwiler for the Canada 
Centre for Remote Sensing (CCRS). This 
sensor is currently flown by Innotech 
Aviation for such applications as oil 
spill monitoring (e.g., during the well- 
known Valdez oil spill) and forest 
inventory mapping. A tentative joint 
program (MEIS III) between an industry 
consortium and the Canadian Government 
is expected to commercialize this 
technology for large scale applications 
through the development of an 
operational sensor-processing system. 
The initial product will have multiple 
imaging channels, including on stereo 
channel, and will cover a 6 km swath at 
lm resolution when flown at 
approximately 4,000 metres. The 
multiband and stereo capability will 
allow extensive spectral discrimination 
as well as digital elevation extraction 
and orthorectification. 
An imaging spectrometer, the 
Fluorescence Line Imager (FLI) was built 
in 1985 by Moniteq for the Canadian 
Department of Fisheries and Oceans. The 
initial need was to image the ocean 
photoplankton by the detection of 
fluorescence of chlorophyll pigments in 
phytoplankton species. The FLI consists 
of a set of 5 spectrometer modules, each 
with a CCD area array detector in the 
output focal plan and operating in the 
400 to 750 nm part of the visible 
spectrum. The high spectral resolution 
and spectral flexibility of data 
acquisition has resulted in the FLI 
being flown in many missions for the 
detection of the fluorescence of 
chlorophyll in oceans, water quality, 
water depth, and the detection of shifts 
in the chlorophyll reflectance "edge". 
A second imaging spectrometer, the 
Compact Airborne Spectrographic Imager 
(CASI) was developed by Itres Research 
Ltd. as a production model device. It 
utilizes reflective optics instead of 
the transmissive optics of the FLI, and 
is a simpler (single array) device. The 
CASI operates in the 450 to 900 nm 
spectral region. 
An airborne LASER FLUORESENSOR, 
utilizing an ultraviolet laser source to 
induce fluorescene, especially in oil, 
was developed by Barringer Research for 
CCRS. The sensor is a profiling device 
and has been flown in many airborne 
missions for oil spill detection and oil 
type characterization. 
An airborne LIDAR BATHYMETER for imaging 
water depth was developed for CCRS by 
Optec. This pulse laser source device 
utilizes the time delay between the 
water surface return and the bottom 
return to infer water depth. The LASER 
BATHYMETER has been used in the Canadian 
arctic and coastal waters to produce the 
first government certified water depth 
chart. Subsequent units are in use 
internationally for airborne water depth 
charting. 
The airborne MICROWAVE RADIOMETER was 
developed for the Atmospheric 
Environment Service by MPB. The two 
frequency (37 and 90 GHz) and two 
polarization imager has flown, for 
several years, on aircraft to acquire 
microwave radiometric images in the 
winter coastal regions for analysis of 
ice characteristics. 
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