28-08-2014, 03:20 PM
TSUNAMI AND EARTHQUAKE ALERT SYSTEM SEMINAR REPORT
TSUNAMI AND EARTHQUAKE.doc (Size: 1.81 MB / Downloads: 156)
ABSTRACT
Earthquakes and Tsunamis strike without warning. The resulting damage can be minimized and lives can be saved if the people living in the earth quake-prone area are already prepared to survive the strike. This requires a warning before the strong ground motion from the earthquake arrives. Such a warning system is possible because the energy wave released at the epicenter travels slower (at 3.5 to 8km/s) than light, which is the principle behind developing this application.
The warning signal from the earthquake or tsunami epicenter can be transmitted to different places using the satellite communication network, fiber-optics network, pager service, cellphone service or a combination of these. The satellite based wireless network such as ISS is idle if system has to cover a large continent like ASIA.
The credential part of the paper lies in the applications part where the applications of ISS as an alert system for “EARTHQUAKE and TSUNAMI” like natural disasters with which the casualties can be reduced drastically. For EARTHQUAKE, TSUNAMI-prone countries like Indonesia, Japan seismic alert system using the ISS network spread throughout the earth is proposed here.
This paper unleashes the system facts such as the network architecture and coverage, satellite constellation, Frequency plan and modulation of ISS system and its operation along with its advantages and applications. Last but not least, the innovative application of ISS as TSUNAMI, EARTHQUAKE alert system is explained in brief.
IRIDIUM SYSTEM ARCHITECTURE
The iridium uses GSM-based telephony architecture to provide a digitally switched telephone network and global roaming feature is designed in to the system.
Operation: The 66-vehicle LEO inter-linked satellite constellation can track the location of a subscriber’s telephone handset, determine the best routing through a network of ground-based gateways and inter-satellite links, establish the best path for the telephone call, Initiate all the necessary connections, and terminate the call upon completion. The unique feature of iridium satellite system is its cross-links.
IRIDIUM SATELLITE CONSTELLATION
The Iridium constellation consists of 66 operational satellites and 14 spares orbiting in a constellation of six polar planes. Each plane has 11 mission satellites performing as nodes in the telephony network. The 14 additional satellites orbit as spares ready to replace any unserviceable satellite. This constellation ensures that every region on the globe is covered by at least one satellite at all times.
Iridium uses 66 operational satellites configured at a mean elevation of 420 miles above earth in six nearly polar orbital times of 100 min 28 sec. The first and last planes rotate in opposite directions, creating a virtual beam. The co-rotating planes are separated by 31.6 degrees and the beam planes are 22 degrees apart.
FREQUENCY PLAN AND MODULATION
All ka-band up-links and cross-links are packetized TDM/FDMA using quadrature phase shift keying and FEC1/2 rate convolutional coding with viterbi decoding.
L-band subscriber to satellite voice links=1.616GHZ TO 1.6265GHZ
Ka-band gateway downlinks=19.4 GHZ to 19.6GHZ.
Ka-band gateway up-links=29.1GHZ to 29.3GHZ
Ka-band inter-satellite cross-links =23.18GHZ to 23.38GHZ
Comparison between iridium and traditional satellite systems: -
Using satellite cross links is the unique key to the iridium system and the primary differentiation between iridium and the traditional satellite bent pipe system where all transmissions follow a path from earth to satellite to earth.
Iridium is the first mobile satellite to incorporate sophisticated, onboard digital processing on each satellite.
Entire global coverage by a single wireless network system.
Only provider of truly global voice and data solutions.
EARTHQUAKE and TSUNAMI ALERT THROUGH ISS
Earthquakes and Tsunamis strike without warning. The resulting damage can be minimized and lives can be saved if the people living in the earth quake-prone area are already prepared to survive the strike. This requires a warning before the strong ground motion from the earthquake arrives. Such a warning system is possible because the energy wave released at the epicenter travels slower (at 3.5 to 8km/s) than light.
The warning signal from the earthquake or tsunami epicenter can be transmitted to different places using the satellite communication network, fiber-optics network, pager service, cell phone service or a combination of these. The satellite based wireless network such as ISS is idle if system has to cover a large continent like ASIA.
For EARTHQUAKE, TSUNAMI-prone countries like Indonesia, Japan seismic alert system using the ISS network spread throughout the earth is proposed here. This system does not try to find the epicenter or the fault line caused by the earthquake.
COMMUNICATING THE DANGER
COMMUNICATING THE DANGER: This GSM-based ISS alert system monitors the earth vibration using a strong motion accelerometer at the earthquake-prone area and broadcasts an alert message to towns and villages through the cellphone network existing throughout the state. Here wireless mobile phones (ISS phones) are used as transmitter and receivers.
The communication system for earthquake alert comprises an earthquake
Sesnsor and interface unit, decision system and alert-disseminiation network