|MadSci Network: Engineering|
Greetings: Fiction writers often use factual information about specific real systems and then combine this information to form "science fiction" systems with capabilities that are far beyond what current technology can do. In some cases these extensions are plausible in other cases they might violate the laws of physics, as we currently understand them. This makes very interesting books and motion pictures but often it confuses the public about what is real and what is fiction. Your questions contain both forms of science fiction. I particularly like the books by Tom Clancy such as Patriot Games in which similar satellite surveillance technology is used to find terrorists; however, even Clancy tends to stay just a little ahead of real technology so that his stories could happen in the future. Unfortunately, Hollywood often stretches the books concepts even farther into the future so that they are less believable if not totally false. In the United States, there are 13 major members of the intelligence community, headed by the Director of Central Intelligence (DCI), Mr.George Tenet (who also leads the Central Intelligence Agency (CIA) - one of the 13 members of the Community). You can read about the mission of these 13 agencies on the DCI web site at: https://www.cia.gov/cia/information/info.html Three key sources of intelligence are SIGINT, IMINT and HUMINT. SIGINT – Signals intelligence is used to monitor electromagnetic energy (e.g. telephone, telegraph, radio, radar, satellite communications, microwave links, air traffic control, cell phones etc.) The National Security Agency (NSA) is a key player in the SIGINT mission. "The SIGINT mission allows for an effective, unified organization and control of all the foreign signals collection and processing activities of the United States." IMINT – Image intelligence is used to collect images with cameras and radar type devices. The National Reconnaissance Office (NRO) is the single, national program to collect the US governments IMINT needs through spaceborne reconnaissance. HUMINT – Human intelligence is acquired by people on the ground (e.g. spies, monitors, bugging, hacking, diplomats etc.) HUMINT is conducted internationally by the Central Intelligence Agency (CIA) and within the United States by the Federal Bureau of Investigation (FBI). http://www.fbi.gov/ IMINT collects images using aircraft (e.g. U2, TR-2) and spacecraft (e.g. KH-11 etc.). The weather, haze and smoke, and atmospheric turbulence and the size of the camera lenses or radar antennas set the limit of resolution (the detail) in the images taken. Aircraft can take pictures with resolution less than an inch from many miles away and automobile license plates and, under the best of conditions, human images can be obtained. Good satellite imagery has resolution of about a meter (3 feet) and can images houses, ships, aircraft but cannot resolve people or small vehicles. A 2-meter (6 ft) tall person would consist of 2 dots (pixels) in a picture with 1-meter resolution. Also, motion pictures can be taken so that 3D views can be generated of objects flown over by aircraft and in some cases spacecraft. Satellites have to look through the whole atmosphere from hundreds of km (miles) in space making detailed images very difficult. Most fiction books and movies greatly exaggerate the resolution of pictures taken from space. About 15 years ago, secret pictures taken by a satellite of a Russian aircraft carrier under construction were leaked to the press and they are the most detailed pictures from space ever released. Several magazines published the pictures at that time. However, the detail of the pictures was not good enough to see people. The book "Deep Black : Space Espionage and National Security" by William E. Burrows / Published 1987 (Publisher Out Of Stock) has these photographs. Perhaps you can find it in your library. These computer-processed pictures are truly amazing. Cameras cannot see through most materials and most countries know when spy satellites are passing overhead so that they keep secret airplanes etc. under cover during these times. Infrared cameras can sense heat patterns such as cool shadows even after some objects has been moved and some information can be obtained from these rapidly fading heat images. It is extremely difficult to take pictures of moving objects or to find objects to photograph during a satellite flyover. The pictures are still picture frames and each frame must be computer processed to remove as much of the atmospheric blurring as possible. Imagine the difficulty of flying over a city in about 5 minutes and trying to find one person in a million, somewhere on the ground, who happened to be out-of-doors, in view of the spacecraft, clear of buildings and without clouds, smog or fog in the way. Imaging radar can see through clouds, weather and nonmetallic materials. The resolution of radar imagery is about 30 cm (1 ft) from aircraft and 10 meters (30 ft) from spacecraft. Even at this resolution, much intelligence information can be obtained - including roads, bridges, dams, airfields, and numbers and types of aircraft and missiles, buildings etc. Spaceborne radar imagery taken from the space shuttle can be found on the NASA/JPL web site at: http://southport.jpl.nasa.gov/ In a fictional story, the writer can combine the resolution of a camera in an aircraft with a camera in a space craft and the penetration capabilities of radar and come up with the "Enemy of the State" type movie. However, even with this sci-fi equipment, one would have to have the ability to quickly find one person in a million, who happens to be in an observable location and not moving very quickly and you see the magnitude of the IMINT problem. SIGINT is a more interesting technique because radio waves and microwaves can pass through most materials except for metals and deep seawater. Thus all types of wireless communications including telephones and cell phones can be monitored from the ground, from the air, and from space. The problem with SIGINT is the huge number of channels that must be monitored at the same time all over the world. Millions of telephone calls, hundreds of thousands of radio channels, radar sets, microwave channels, air traffic control signals, police and fire radios etc. Determining which channels have good intelligence information and which are just kids talking is a huge problem. Who can possibly listen to millions the calls? For that, you would need millions of listeners. The NSA monitors all of these signals, all over the world, all of the time and records them. No one can possible sort through this huge amount of data unless a time, location and hopefully a channel frequency can be zeroed in on. This is why it can take many hours or days to recover the communications such as those between the Russian fighter pilots when they shot down the Korean Boeing 747 as it strayed off course over the Soviet Union about 10 years ago. The general location was known, the general time was known and the frequencies of aircraft communications channels where known, yet it still required hours of searching through the recordings from many different SIGINT locations to find out what happened. However, when they did recover the communications between the fighter pilots they had a very graphic sound picture of the killing of about 250 people! More recently the news people, private detectives (and others) have figured out how to use SIGINT and have eavesdropped on the cell phone and wireless remote telephone conversations of many famous and ordinary people. By placing a radio bug on a person or a vehicle it is often possible to find the location of people perhaps to take pictures. This can be used for bad purposes or for good purposes such as tracking down stolen automobiles. Perhaps one of the most interesting SIGINT leaks was discussed in the nonfiction book "Spy Catcher" by Peter Wright in which spies eavesdropped on computer terminals in foreign embassies by listening to the electronic noise signals that most computers and FAX machines radiate. This is part of the HUMINT mission which uses people on the ground to collect information. This is the most difficult and sometimes the most useful or sometimes the most unreliable source of information. Today in the real world we are being monitored by ultra miniature video cameras, voice and TV wireless transmitters, wire tapping and cell phone monitoring, wireless telephone listening, computer hacking and eavesdropping of all sorts is being used to invade our privacy. These are much more threatening to our freedom than remote sensing from aircraft or space will ever become. Best regards, Your Mad Scientist Adrian Popa
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