THE JAMMING OF A SATELLITE SIGNAL
By Manuel Cereijo
Most communication satellites are placed in geostationary orbit (GEO). This is a circular orbit in Earth's equatorial plane. The orbit is located 22,300 miles above the equator so that the orbital period is the same as that of the Earth. Consequently, from Earth these satellites appear to be located at a stationary point in the sky. This enables the Earth station antennas to be simplified since they are pointed in a fixed direction and do not have to track a moving object. For communications to the polar regions of the Earth, satellites in polar orbits are used, which require Earth stations with tracking antennas.
The most desired frequency band for satellite communication systems is 6GHz on the uplink(Earth to satellite transmission) and 4GHz on the downlink ( satellite to Earth transmission). In this frequency range the equipment is relatively inexpensive, the cosmic noise is small, and the frequency is low enough so that rainfall does not appreciable attenuate the signals. Other losses, such as ionospheric scintillation and atmospheric absorption, are small at these frequencies. The FCC limits the power density on Earth from the satellite transmitters to avoid interference with microwave radio relays assigned to work in the 6 and 4 GHz bands.In the 6/4 GHz band, synchronous satellites are assigned an orbital spacing of 2 degrees.
Newer satellites operate in higher frequencies bands. The Ku band satellites use 14GHz on the uplink and 12 GHz on the downlink with orbital spacing of 3 degrees. Some new Ku band satellites have high power amplifiers that feed 120 to 240 Watts into their transmitting antenna, as compared with 20 to 40 Watts for low-or medium-power satellites. High power satellites-called direct broadcast satellites-(DBS), provide TV service directly to the homeowner that has a small receiving antenna (2 ft or less in diameter).
Each satellite has a number of transponders (receiver-to-transmitter) aboard to amplify the received signal from the uplink and to down-convert the signal for transmission on the downlink. That is why it is easier to jam the uplink signal, as Cuba is doing.
These transponders are called "bent pipe transponders" because they do not demodulate the received input signal but just perform a signal processing as a high power gain down converter, using a traveling wave tube amplifier. Most transponders are designed for a bandwidth of 36, 54, or 72 MHz., with 36 MHz being the standard use for the 6/4 GHZ television relay service.
Satellite communication systems do differ from terrestrial microwave links in the techniques used for multiple access of a single transponder by multiple uplink and multiple downlink stations. The most widely used methods are: FAMA mode using either FDMA, TDMA, or CDMA techniques, or a DAMA mode using either FDMA, TDMA, or CDMA techniques.
Since January, 1998, in spite that very little has been written about the Bejucal base in Cuba, Cuba's system of international communications surveillance and jamming efforts, is in full operation. Most of what has been written has been ignored by US and European authorities. Bejucal is an electronic espionage base used by the Cuban military intelligence to intercept, interfere, intrude, and process international communications passing via communications satellites.
Other parts of the same system intercept messages from the Internet, from undersea cables, from radio transmissions, from secret equipment installed inside embassies, or use orbiting satellites to monitor signals anywhere on the earth's surface.
JAMMING FROM CUBA OF TRANSMISSION TO IRAN
Just a few days ago, Friday, July11, sources associated with the broadcast services to Iran confirmed that Loral Skynet, the operator of the Telstar-12 satellite used by the broadcasters, had determined the jamming was coming from the vicinity of La Habana.
One of the sources said that Loral, working with transmitter location expert TLS Inc, of Chantilly, Va. Had further fixed the location as "20 miles outside of La Habana. Cuba's Bejucal base is about 20 miles outside La Habana, at
220 56' 00" 820 23' 30"
Iran and Cuba have had increasingly close relations over the past several years with Iran supplying Cuba with oil, and Cuba building the largest Biotechnological and Genetic Engineering Center of the region to Iran. Cuba has extensive jamming experience, regularly interfering with the TV Marti signal.
The world's most secret electronic surveillance system has its main origin in the former Soviet Union Lourdes base in Cuba.. In a deeper sense, it results from the invention of radio and the fundamental nature of telecommunications. The creation of radio permitted governments and other communicators to pass messages to receivers over transcontinental distances. But there was a penalty - anyone else could listen in. Previously, written messages were physically secure (unless the courier carrying them was ambushed, or a spy compromised communications). The invention of radio thus created a new importance for cryptography, the art and science of making secret codes. It also led to the business of signals intelligence, now an industrial scale activity.
Dozens of advanced nations use sigint as a key source of intelligence. Even smaller European nations such as Denmark, the Netherlands or Switzerland have recently constructed small, stations to obtain and process intelligence by eavesdropping on civil satellite communications. All of them are smaller than Cuba's Bejucal, and none of them are so close to the United States.
Everything produced in the Bejucal sigint base is marked by hundreds of special codewords that "compartmentalize" knowledge of intercepted communications and the systems used to intercept them.
The scale and significance of the global surveillance system has been transformed since 1980. The arrival of low cost wideband international communications has created a wired world. But few people are aware that the first global wide area network (WAN) was not the internet, but the international network connecting sigint stations and processing centers.
By the early 1970s, the laborious process of scanning paper printouts for names or terms appearing on the "watch lists" had begun to be replaced by automated computer systems. These computers performed a task essentially similar to the search engines of the internet. Prompted with a word, phrase or combination of words, they will identify all messages containing the desired words or phrases.
Their job, now performed on a huge scale, is to match the "key words" or phrases of interest to intelligence agencies to the huge volume of international communications, to extract them and pass them to where they are wanted. During the 1980s, the NSA developed a "fast data finder" microprocessor that was optimally designed for this purpose. It was later commercially marketed, with claims that it "the most comprehensive character-string comparison functions of any text retrieval system in the world". A single unit could work with:
*trillions of bytes of textual archive and thousands of online users, or gigabytes of live data stream per day that are filtered against tens of thousands of complex interest profiles.
Although different systems are in use, the key computer system at the heart of a modern sigint station's processing operations is the "Dictionary". Bejucal contains a Dictionary. Portable versions are even available, and can be loaded into briefcase-sized units known as "Oratory" 10 .
The Dictionary computers scan communications input to them, and extract for reporting and further analysis those that match the profiles of interest.
In one sense, the main function of Dictionary computers are to throw most intercepted information away.
The "common" automated processing equipment (ADPE) in the Bejucal base include the following elements:
· Local management subsystem
There are 10 satellite antennas at Bejucal . There were 12 at Lourdes
New methods which have been developed during the 1990s are available to recognize the "topics" of phone calls, and allow to automate the processing of the content of telephone messages Under the rubric of "information warfare", the sigint bases also hope to overcome the ever more extensive use of encryption by direct interference with and attacks on targeted computers. These methods include information stealing viruses, software audio, video, and data bugs, and pre- emptive tampering with software or hardware ("trapdoors").
The Sigint world has changed. Now the United States has to go out after sporadic miniwars and terrorism. Also, the terrorists have sigint facilities. One of them: the sigint base of Bejucal, Cuba.
Before the widespread use of fiber optic cables, geosynchronous satellite constellations- USA, Russia, China- carried much of the international communications traffic. Such links can be comprehensively monitored by placing a receiving station in each satellite's transmission footprint.
In contrast, cables have to be tapped directly. While this is easy to do if the cable is in one's territory, someone has to visit the cable clandestinely if it doesn't, typically in a submarine.
Fiber optic cables are the toughest to crack: fibers don't radiate helpful electromagnetic fields that can be detected with an inductively coupled pick-up collar. Eavesdropping first solved this problem by targeting the signal-boosting repeater stations strung along the cables.
Early repeaters had to convert the signal from light into electricity and back again in order to amplify it, and in its electronic stage, the signal could be tapped externally in much the same way as a copper cable. But the development of erbium-doped fiber amplifiers, in which the signal is boosted without ever being converted into electricity, called for a new approach.
Another challenge are fiber optic cables that stay on land. One of the things that Cuban elite troops are trained to do is going ashore and getting to the nearest land line. They try to see how many taps they can put on our fiber optic networks. Cuban elite troops, similar to US special troops, and navy seals, are trained at the Baragua School, in El Cacho, near Los Palacios, Pinar del Rio. When another approach is needed, they include breaking into embassies or facilities of communications providers and stealing information or installing bugs.
By bugging a computer or communications system, information can be captured before it is sent through a fiber optic cable. A tiny microphone dropped into a key board can pick up the sound made by the keys as they struck and transmit the sounds to a nearby receiver. Different keys sound different-each has a specific signature. Those signatures can be used to reconstruct what was typed.
In effect, whether or not the Bejucal base is of value, boils down to a technical question: in the face of a telecommunications explosion that has brought e-mail, cellphones, beepers, instant messaging, fiber optic cables, faxes, video-conferencing, and the World Wide Web to every corner of the World, can the intelligence Bejucal base attain enough access to know what is going on?
Of course, some communications are easier to access than others. Wireless communications in particular offer two key advantages-you can intercept them without physically tapping into the target's communications system, and there is no way to detect that they have been intercepted.
Microwave, radio, telephone, walkie-talkie-communications, satellite-communications that are in the air are all interceptible by some sort of antenna in the right place. Cell-and satellite phones can also reveal a caller's location. The location may be determined if multiple listening stations, possibly including satellites can pick up the phone's transmissions.
Radio transmissions, including those from cell phones, can be picked up by the Bejucal base. Satellites tied to the Base ( from PRC) may also pick up microwave transmissions.
The rise of ubiquitous computer communications has allowed the emergence of widely available strong cipher systems, such as public key cryptography, which rely on mathematical functions that would take the greatest supercomputer on earth millennia to break.
The electrical engineers and computer scientists at Cuba's Bejucal base spend a lot of their time developing automatic filter systems. They focus on telephone calls from a particular installation, search for specific words and phrases in e-mails, or use voice recognition techniques. They have a long volume, some two million pieces of communications an hour. Remember, it is not only what you say, it is the way that you say it.
GETTING THE MESSAGE
Data mining and other techniques for extracting coherent patterns of information from a flood of bits are near the top of the new research at Bejucal's. A case in point: they are working on the development of a program that scans 50 news services from around the world in order to collate and summarize accounts of each day's news. This is of particular interest to Castro.
This technique will permit also to work with the less structured texts found in intercepted e-mail messages, chat sessions, and speech transcripts, and will also improve the system's analytical tools. They are also working on the parallelization of the classification algorithms, which currently take more than eight hours on a fast PC to generate each day's summary.
Another important aspect is speech recognition. They ( Cubans) are working on talk-printing techniques. This refers to utilizing variations in pitch, rhythm, and speech volume-information that speech recognition programs typically throw out-to refine word and sentence recognition, to identify speakers, and even to tell casual chats from serious discussions or the dissemination of orders and instructions. These variations in speaking style are known as prosody. Prosody can help analysts make sense of otherwise ambiguous transcriptions, in cases such as distinguish, for example, between "Don't go"! and "Don't! Go!".
By analyzing speaking styles, it may be possible to tell when people are using code words to discuss illicit business.
China has converted an ICBM base at Taiyuan, southwest of Beijing, into a satellite- launching center. China is only the third country in the world to operate recoverable satellites, which can bring photographic film and experimental specimens back to earth.
The first satellite to be launched on Earth in the 21st century was a test of the Shenzhou-2 unmanned spaceship on January 9, 2001. China has launched 20 space vehicles since January 2001 up to date. This is twice the annual rate of the 1990s.
In 1999, Raul Castro, Defense Minister of Cuba signed an agreement with Chi Hoatin, Defense Minister of China, and General Dong Liang Ju, of China, where the Chinese could be part of the operations of the Bejucal base, and Cuba could use China's communication satellites.
The activities performed at the Bejucal base pose a serious threat to the national security of the United States
One Bejucal antenna
FORMER LOURDES BASE (DISMANTLED)
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