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Background
Prior to sophisticated airborne and space-based relay platforms, the prevailing method for transmitting over-the-horizon waveforms was via high
frequency signaling. In the frequency range of 3MHz to 30MHz, the F layers of the ionosphere act as reflectors and bounce signals back to earth.
High Frequency (HF) signals take advantage of this ionospheric property and transmit many types of signals over the horizon to distant receiving
locations. However, a distinct disadvantage of HF signaling is the limited frequency bandwidths and data speeds that can be accommodated in this
spectrum. The reasons for this are many, ranging from traditional signaling modulation methods to standardized limitations of the spectrum. The
advantages in transmitting at frequencies above HF include the capability of wider bandwidths, less interference with high duty cycle transmissions
found in the upper HF band (such as CB radio), and higher data signaling and information throughput. As meteors impact the atmosphere, their
passage leaves ionized trails behind them as they disintegrate. For the short time that the ionized trail exists, the trail possesses a reflector
capability. In the HF spectrum (3-30 MHz), natural atmospheric ionization properties exist that reflect signals in this frequency range over the horizon.
Ionized trails provide a reflective capability ranging from approximately 30 to 1 50MHz in the upper atmosphere between 60 and 100 miles in altitude,
although MBC activity is most often seen in the 40 to 60 MHz frequency range. These Low Very High Frequency (LVHF) transmissions provide
alternatives to the busy HF frequency bands and offer higher bandwidth and data throughput capabilities. Typical LVHF transmissions have less
range due to signal dispersion and penetration of the atmosphere into space. MBC ionized trails of sufficient density average between 100 and 500
milliseconds, but larger sized meteorites can generate a dense trail lasting up to several seconds. According to Starcom, a commercial company
developing and selling MBC systems claims that their system can transmit data at around 16-20 kilobits per second (16,000-20,000 bits) and in
lengths of a few hundred characters. But the data are sent in packages, so there is no limit to the length of message that could be sent, If may simply
take more than one meteor burst to convey it.
The typical MBC link involves a Master Station and a Remote Station. During a MBC transmission, a Master Station calculates the incidence angle
(which includes the azimuth and elevation of the transmitting antenna) necessary to communicate with a remote station, and the Remote Station also
calculates its specific incidence angle. The Master Station begins transmission by pulsing a probe signal that consists of a short duty cycle pulse.
The pulse contains a data header identifying the station and a binary trigger that the Remote Station uses to respond to the probe. When an
appropriate trail is found, the probe completes its transmission path to the Remote Station. The Remote Station responds by transmitting its data on
a different frequency while still receiving the probe from the Master Station. Until the probe signal disappears (when the specific trail used to connect
the two facilities dissipates), the Remote Station will continue to transmit its data. When the probe signal is no longer detected, the Remote Station
continues to monitor the transmit frequency for the probe pulse from the Master Station. The exchange of information can be in either direction. The
data exchanged between stations typically contains short messages such as telemetric data, text, and even near-real-time voice. Each station has
the ability to manipulate successive bursts of data into a coherent transmission. Because there are so many meteor impacts in the upper
atmosphere, the delays are not as significant as one would expect.
The overall number of meteor impacts in the atmosphere varies based on daily and seasonal activity periods. Due to the Earths rotation, more
impacts ore seen in the morning and less in the evening. This phenomenon is caused by the terminus line (the line separating day from night)
moving towards the sun in the morning and away’ from the sun at night. Known as the diurnal variance, the ratio of morning to evening meteor trails
can vary up to a five to one ratio. Another aspect of MBC is the seasonal variations that result in the Northern Hemisphere experiencing more meteor
impacts in the summer and less in the winter, and conversely, higher activity in the summer months and lower activity during the winter in the
Southern Hemisphere. Other variations include sunspot cycles and meteoroid showers, such as the Leonids.
Meteorites impacting the atmosphere have many properties such as the incident angle and the associated number of overdense and “underdense”
trails capable of supporting a MBC link. Overdense and underdense trails are defined as the electron density per meter, and is usually defined as 1
X 1014 electrons/meter. MBC links are focused on the underdense trail. This is primarily due to the lack of variability in the ionized trail of an
underdense trail when compared to an overdense trail. For example, overdense trails have a relatively slow rise to peak density, a longer duration,
and a correspondingly slow diffusion from peak density. Underdense trails have a much faster rise time to peak strength and a correspondingly fast
slope to total diffusion. The lack of variability in an underdense ionized trail is a strength because the reflectivity of the signal waveform encounters
much fewer distortions. Typical distortions include signal diffusion within a trail and multipath effects. Overdense trails have much higher incidences
of signaling distortion associated with them. The higher free electron content of an overdense trail causes amplitude and time distortions that can
significantly affect the information throughput received by both transmitter and receiver. Overdense trails also encounter variations in electron
density throughout the overall trail duration time.
Although studies of Meteor Burst were done in the early 20th century, the first system to fully explore MBC was JANET. It was a Canadian-funded
system implemented in the 1950’s. Prior to communications satellites, the methods available for over-the-horizon communications were limited to HF
communications and landline systems. The Canadian government sought to explore the ability of using the high density of meteorite activity in their
far northern latitudes to communicate with the larger population centers in the south without interfering with HF systems already in place. About the
same timeframe, US military applications of MBC included experiments conducted by NATO under the name COMET2.
In 1970, the US Department of Agriculture established a system called SNOTEL to collect data from hundreds of unmanned remote sites spread over
several western states. The system was designed to provide remote monitoring and transmission of meteorological data such as snow pock levels,
water content and atmospheric conditions such as temperature and barometric levels. Active today, the SNOTEL network provides critical information
involving forecasting and planning in areas ranging from meteorology to water consumption. The network is used to monitor snow pack depth, water
content, wind speed, humidity, and other conditions from 600 SNOTEL sites in 11 western states, including Alaska. The sites are located in remote
high-mountain watersheds where access is often difficult or restricted. Two Master Stations, in Boise, Idaho and Ogden, Utah, control the SNOTEL
Remote Stations. SNOTEL uses two frequencies; 40.530 and 41.530 MHz with output power from the master stations averaging 1500 watts. The
remote sites transmit on 41.530 MHz with 100 watts of power.
Current Systems
Meteor Burst systems in use today includes SNOTEL, the Alaskan Air Command System, an Egyptian Water Telemetry System, a Chinese
Communication network, and the Pakistani Flood Warning System, as well as many others. Many MBC users implement an architecture that requires
little or no human intervention. Telemetric usage for monitoring natural and artificial phenomena is growing. Applications involving safety and
advanced warning, especially concerning natural disasters and resource planning, is ideal for MBC networks.
The Alaska Meteor Burst Communications system (AMBCS) is a joint National Weather Service, Corps of Engineers, and Bureau of Land
Management network. This system operates a Master Station in Anchorage and Remote Stations located in Alaskan wilderness areas to both collect
aeronautical and environmental data and provide message communications service among remote manned camps.
China has implemented a MBC network that connects its northern and western borders to Master Stations located in Larigzhou, Beijing, and Urumqi.
This system is primarily used to support low-level communications network and provides a backup to high priority data traffic from these regions.
In Egypt, water telemetry is carried out through the Telemetry Project which consists primarily of installing a countrywide MBC telemetry system that
provides the Ministry with real time data related to the physical status of the Nile River Irrigation System. The meteor burst telemetry system is
designed to operate with very low power consumption and obtains its power from solar powered batteries. The system also provides the capability to:
remotely control water regulators and pump stations; reports times when pumps are turned on and off; and reports water quality and climatologic
parameters measurable by electromechanical sensors. This project was funded by the US Agency for International Development (USAID) on behalf
of the Egyptian Ministry of Public Works and Water Resourcesó.
The Water and Power Development Authority of Pakistan (WAPDA) uses a MBC system developed by Meteor Communications Corp. Their meteor
burst system gathers hydro meteorological data for both the Snow and Ice Operations Center and for the Flood Forecast Monitoring Center in
Lahore. The network is located in remote areas of the high altitude mountain ranges on Pakistan’s northern border. MBC Remote Stations have
been installed in the Himalayan, Hindukush, and Karakoram mountain ranges. The network has a total coverage area of 122,000 square miles.
StarCom Corp. located in Bellingham, Washington has implemented a MBC network to support American Medical Response (AMR), a nationally
known ambulance services firm. Starcom augments AMRs GPS-based radios switch by adding a meteor burst mode, sending back their GPS data
every three minutes or so to keep track of the vehicles. AMR responds to geographical areas where typical cellular or other network coverage
capabilities cannot support operations and status awareness. A key attribute of the existing AMR network is the constant tracking of corporate
vehicles wherever they are. In some cases, the ability to respond in the shortest time is compromised by the lack of communications between control
centers and remote vehicles. StarCom has started marketing its radios and meteor burst systems to other companies, such as shipping companies
and railways whose work pulls them out of cellular range.
Future Evolution
Meteor Burst systems and implementation is not solely a government function. Amateur radio enthusiasts have implemented MBC systems that, in
some locations, augment civil communications capabilities. MBC systems are growing in number and application. The network cost structure is
extremely inexpensive and provides for automated operations, which further reduces costs. Other applications of MBC systems include lifesaving
functions, vehicle tracking, remote sensor and telemetry functions and military applications.
MBC can operate as a stand-alone communications network, but its greatest strength lies in augmenting other systems for reliability and
assuredness. MBC is an extremely simplified operational model. Modern advances in digital signal processing hardware such as reduced
microprocessor sizes and increased speed, as well as adaptive software applications will greatly benefit the applicability of MBC to virtually any
mission profile.
Military applications of MBC will likely see growth because of inherent technical advantages enjoyed by MBC. These include an inherent anti-jam, low
probability of detection/low probability of interception (LPD/LPI) characteristics. Modifying MBC communications via radio frequency characteristics
and advanced encoding ensures a secure, reliable transmission vehicle. In environments involving detonation of nuclear weaponry, MBC is
extremely resilient to effects that can destroy or severely degrade primary communications systems currently in use, such as battalion and brigade
level multichannel radio networks. A current U.S. Army initiative called the Joint Tactical Radio System may well benefit from MBC capabilities,
especially for special versions delivered to remote operating elements such as Special Operations Forces. With a small received footprint (—5 X 25
mile ellipse), security and isolation can be achieved for these applications. The potential applicability of MBC is widespread and touches on services
and industries in many areas. See Table 2 for MBC Future Growth Opportunities.
The likelihood of MBC becoming a first-line communications methodology is low due to existing technology systems and their related capabilities.
However, MBC offers an inexpensive and robust architecture that complements, supplements, and even replaces current infrastructures when
needed. The ability to utilize naturally occurring phenomena to establish reliable and effective communications improves the overall network
performance curve. The implementation costs associated with establishing MBC links is small when compared to wireline application infrastructures.
MBC offers many users the ability to inexpensively implement a beyond line of sight communications capability that can be applied to many different
level-of-service profiles. Businesses that may profit by implementing MBC include oil and gas companies with remote land or sea facilities,
organizations that maintain remote unattended or infrequently- visited facilities. The MBC architecture can be implemented with basic duplex
communications equipment or outfitted with complex signal processing hardware and software enabling high data throughput via advanced data
compression techniques. The architecture is designed for remote implementation and operations and much of its infrastructure requires little
consistent human intervention. Complementary service and integration with existing network architectures is a natural fit for MBC networks, as little
overlap exists with current wire line and wireless applications. This clear separation enhances the ability of MBC to provide overflow or emergency
communications and significantly reduces the single point of failure weakness found in many collocated and technology- dependent infrastructure
networks. MBC has extraordinary potential and upside for many organizations that can be effectively implemented in 21st century businesses and
telecommunications infrastructures. The technology is extremely underutilized and represents a significant force-multiplier for civil government,
industry, and military communications capabilities.
Prior to sophisticated airborne and space-based relay platforms, the prevailing method for transmitting over-the-horizon waveforms was via high
frequency signaling. In the frequency range of 3MHz to 30MHz, the F layers of the ionosphere act as reflectors and bounce signals back to earth.
High Frequency (HF) signals take advantage of this ionospheric property and transmit many types of signals over the horizon to distant receiving
locations. However, a distinct disadvantage of HF signaling is the limited frequency bandwidths and data speeds that can be accommodated in this
spectrum. The reasons for this are many, ranging from traditional signaling modulation methods to standardized limitations of the spectrum. The
advantages in transmitting at frequencies above HF include the capability of wider bandwidths, less interference with high duty cycle transmissions
found in the upper HF band (such as CB radio), and higher data signaling and information throughput. As meteors impact the atmosphere, their
passage leaves ionized trails behind them as they disintegrate. For the short time that the ionized trail exists, the trail possesses a reflector
capability. In the HF spectrum (3-30 MHz), natural atmospheric ionization properties exist that reflect signals in this frequency range over the horizon.
Ionized trails provide a reflective capability ranging from approximately 30 to 1 50MHz in the upper atmosphere between 60 and 100 miles in altitude,
although MBC activity is most often seen in the 40 to 60 MHz frequency range. These Low Very High Frequency (LVHF) transmissions provide
alternatives to the busy HF frequency bands and offer higher bandwidth and data throughput capabilities. Typical LVHF transmissions have less
range due to signal dispersion and penetration of the atmosphere into space. MBC ionized trails of sufficient density average between 100 and 500
milliseconds, but larger sized meteorites can generate a dense trail lasting up to several seconds. According to Starcom, a commercial company
developing and selling MBC systems claims that their system can transmit data at around 16-20 kilobits per second (16,000-20,000 bits) and in
lengths of a few hundred characters. But the data are sent in packages, so there is no limit to the length of message that could be sent, If may simply
take more than one meteor burst to convey it.
The typical MBC link involves a Master Station and a Remote Station. During a MBC transmission, a Master Station calculates the incidence angle
(which includes the azimuth and elevation of the transmitting antenna) necessary to communicate with a remote station, and the Remote Station also
calculates its specific incidence angle. The Master Station begins transmission by pulsing a probe signal that consists of a short duty cycle pulse.
The pulse contains a data header identifying the station and a binary trigger that the Remote Station uses to respond to the probe. When an
appropriate trail is found, the probe completes its transmission path to the Remote Station. The Remote Station responds by transmitting its data on
a different frequency while still receiving the probe from the Master Station. Until the probe signal disappears (when the specific trail used to connect
the two facilities dissipates), the Remote Station will continue to transmit its data. When the probe signal is no longer detected, the Remote Station
continues to monitor the transmit frequency for the probe pulse from the Master Station. The exchange of information can be in either direction. The
data exchanged between stations typically contains short messages such as telemetric data, text, and even near-real-time voice. Each station has
the ability to manipulate successive bursts of data into a coherent transmission. Because there are so many meteor impacts in the upper
atmosphere, the delays are not as significant as one would expect.
The overall number of meteor impacts in the atmosphere varies based on daily and seasonal activity periods. Due to the Earths rotation, more
impacts ore seen in the morning and less in the evening. This phenomenon is caused by the terminus line (the line separating day from night)
moving towards the sun in the morning and away’ from the sun at night. Known as the diurnal variance, the ratio of morning to evening meteor trails
can vary up to a five to one ratio. Another aspect of MBC is the seasonal variations that result in the Northern Hemisphere experiencing more meteor
impacts in the summer and less in the winter, and conversely, higher activity in the summer months and lower activity during the winter in the
Southern Hemisphere. Other variations include sunspot cycles and meteoroid showers, such as the Leonids.
Meteorites impacting the atmosphere have many properties such as the incident angle and the associated number of overdense and “underdense”
trails capable of supporting a MBC link. Overdense and underdense trails are defined as the electron density per meter, and is usually defined as 1
X 1014 electrons/meter. MBC links are focused on the underdense trail. This is primarily due to the lack of variability in the ionized trail of an
underdense trail when compared to an overdense trail. For example, overdense trails have a relatively slow rise to peak density, a longer duration,
and a correspondingly slow diffusion from peak density. Underdense trails have a much faster rise time to peak strength and a correspondingly fast
slope to total diffusion. The lack of variability in an underdense ionized trail is a strength because the reflectivity of the signal waveform encounters
much fewer distortions. Typical distortions include signal diffusion within a trail and multipath effects. Overdense trails have much higher incidences
of signaling distortion associated with them. The higher free electron content of an overdense trail causes amplitude and time distortions that can
significantly affect the information throughput received by both transmitter and receiver. Overdense trails also encounter variations in electron
density throughout the overall trail duration time.
Although studies of Meteor Burst were done in the early 20th century, the first system to fully explore MBC was JANET. It was a Canadian-funded
system implemented in the 1950’s. Prior to communications satellites, the methods available for over-the-horizon communications were limited to HF
communications and landline systems. The Canadian government sought to explore the ability of using the high density of meteorite activity in their
far northern latitudes to communicate with the larger population centers in the south without interfering with HF systems already in place. About the
same timeframe, US military applications of MBC included experiments conducted by NATO under the name COMET2.
In 1970, the US Department of Agriculture established a system called SNOTEL to collect data from hundreds of unmanned remote sites spread over
several western states. The system was designed to provide remote monitoring and transmission of meteorological data such as snow pock levels,
water content and atmospheric conditions such as temperature and barometric levels. Active today, the SNOTEL network provides critical information
involving forecasting and planning in areas ranging from meteorology to water consumption. The network is used to monitor snow pack depth, water
content, wind speed, humidity, and other conditions from 600 SNOTEL sites in 11 western states, including Alaska. The sites are located in remote
high-mountain watersheds where access is often difficult or restricted. Two Master Stations, in Boise, Idaho and Ogden, Utah, control the SNOTEL
Remote Stations. SNOTEL uses two frequencies; 40.530 and 41.530 MHz with output power from the master stations averaging 1500 watts. The
remote sites transmit on 41.530 MHz with 100 watts of power.
Current Systems
Meteor Burst systems in use today includes SNOTEL, the Alaskan Air Command System, an Egyptian Water Telemetry System, a Chinese
Communication network, and the Pakistani Flood Warning System, as well as many others. Many MBC users implement an architecture that requires
little or no human intervention. Telemetric usage for monitoring natural and artificial phenomena is growing. Applications involving safety and
advanced warning, especially concerning natural disasters and resource planning, is ideal for MBC networks.
The Alaska Meteor Burst Communications system (AMBCS) is a joint National Weather Service, Corps of Engineers, and Bureau of Land
Management network. This system operates a Master Station in Anchorage and Remote Stations located in Alaskan wilderness areas to both collect
aeronautical and environmental data and provide message communications service among remote manned camps.
China has implemented a MBC network that connects its northern and western borders to Master Stations located in Larigzhou, Beijing, and Urumqi.
This system is primarily used to support low-level communications network and provides a backup to high priority data traffic from these regions.
In Egypt, water telemetry is carried out through the Telemetry Project which consists primarily of installing a countrywide MBC telemetry system that
provides the Ministry with real time data related to the physical status of the Nile River Irrigation System. The meteor burst telemetry system is
designed to operate with very low power consumption and obtains its power from solar powered batteries. The system also provides the capability to:
remotely control water regulators and pump stations; reports times when pumps are turned on and off; and reports water quality and climatologic
parameters measurable by electromechanical sensors. This project was funded by the US Agency for International Development (USAID) on behalf
of the Egyptian Ministry of Public Works and Water Resourcesó.
The Water and Power Development Authority of Pakistan (WAPDA) uses a MBC system developed by Meteor Communications Corp. Their meteor
burst system gathers hydro meteorological data for both the Snow and Ice Operations Center and for the Flood Forecast Monitoring Center in
Lahore. The network is located in remote areas of the high altitude mountain ranges on Pakistan’s northern border. MBC Remote Stations have
been installed in the Himalayan, Hindukush, and Karakoram mountain ranges. The network has a total coverage area of 122,000 square miles.
StarCom Corp. located in Bellingham, Washington has implemented a MBC network to support American Medical Response (AMR), a nationally
known ambulance services firm. Starcom augments AMRs GPS-based radios switch by adding a meteor burst mode, sending back their GPS data
every three minutes or so to keep track of the vehicles. AMR responds to geographical areas where typical cellular or other network coverage
capabilities cannot support operations and status awareness. A key attribute of the existing AMR network is the constant tracking of corporate
vehicles wherever they are. In some cases, the ability to respond in the shortest time is compromised by the lack of communications between control
centers and remote vehicles. StarCom has started marketing its radios and meteor burst systems to other companies, such as shipping companies
and railways whose work pulls them out of cellular range.
Future Evolution
Meteor Burst systems and implementation is not solely a government function. Amateur radio enthusiasts have implemented MBC systems that, in
some locations, augment civil communications capabilities. MBC systems are growing in number and application. The network cost structure is
extremely inexpensive and provides for automated operations, which further reduces costs. Other applications of MBC systems include lifesaving
functions, vehicle tracking, remote sensor and telemetry functions and military applications.
MBC can operate as a stand-alone communications network, but its greatest strength lies in augmenting other systems for reliability and
assuredness. MBC is an extremely simplified operational model. Modern advances in digital signal processing hardware such as reduced
microprocessor sizes and increased speed, as well as adaptive software applications will greatly benefit the applicability of MBC to virtually any
mission profile.
Military applications of MBC will likely see growth because of inherent technical advantages enjoyed by MBC. These include an inherent anti-jam, low
probability of detection/low probability of interception (LPD/LPI) characteristics. Modifying MBC communications via radio frequency characteristics
and advanced encoding ensures a secure, reliable transmission vehicle. In environments involving detonation of nuclear weaponry, MBC is
extremely resilient to effects that can destroy or severely degrade primary communications systems currently in use, such as battalion and brigade
level multichannel radio networks. A current U.S. Army initiative called the Joint Tactical Radio System may well benefit from MBC capabilities,
especially for special versions delivered to remote operating elements such as Special Operations Forces. With a small received footprint (—5 X 25
mile ellipse), security and isolation can be achieved for these applications. The potential applicability of MBC is widespread and touches on services
and industries in many areas. See Table 2 for MBC Future Growth Opportunities.
The likelihood of MBC becoming a first-line communications methodology is low due to existing technology systems and their related capabilities.
However, MBC offers an inexpensive and robust architecture that complements, supplements, and even replaces current infrastructures when
needed. The ability to utilize naturally occurring phenomena to establish reliable and effective communications improves the overall network
performance curve. The implementation costs associated with establishing MBC links is small when compared to wireline application infrastructures.
MBC offers many users the ability to inexpensively implement a beyond line of sight communications capability that can be applied to many different
level-of-service profiles. Businesses that may profit by implementing MBC include oil and gas companies with remote land or sea facilities,
organizations that maintain remote unattended or infrequently- visited facilities. The MBC architecture can be implemented with basic duplex
communications equipment or outfitted with complex signal processing hardware and software enabling high data throughput via advanced data
compression techniques. The architecture is designed for remote implementation and operations and much of its infrastructure requires little
consistent human intervention. Complementary service and integration with existing network architectures is a natural fit for MBC networks, as little
overlap exists with current wire line and wireless applications. This clear separation enhances the ability of MBC to provide overflow or emergency
communications and significantly reduces the single point of failure weakness found in many collocated and technology- dependent infrastructure
networks. MBC has extraordinary potential and upside for many organizations that can be effectively implemented in 21st century businesses and
telecommunications infrastructures. The technology is extremely underutilized and represents a significant force-multiplier for civil government,
industry, and military communications capabilities.
| Zubia Zubair |
| Cover Story (Feb 2005) |
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| TelecomPlus |
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