Figure 3 (58 k)
1.
ABSTRACT
The
University of Guam PEACESAT (UOG PEACESAT) station provides non profit
public services to over a three million square mile area of the tropical
north Pacific, generally referred to as Micronesia. Within this area,
only 8 of over 200 significantly populated islands (with a teacher
or dispensary) have any off island communication facilities, except
for HF radio systems. The outer islands of Yap, Chuuk, Pohnpei, and
Majuro are more populated, than the INTELSAT and PEACESAT (public
service telecommunications) serviced main centers. In order to network
remote Micronesian medical and educational facilities, small, robust,
marine grade narrow-band earth stations need to be developed.
This
paper presents a vision of rugged 3 meter S/L band earth stations
strategically located over the outer Micronesian Islands that do not
have INTELSAT or PEACESAT earth stations. These simple solar
powered narrow-band links would serve remote educational and medical
learning centers and would provide emergency communications during
environmental and natural disasters in coordinating state relief workers.
We hope that the industry could provide a narrow-band single
three channel (2 simplex and one duplex) transceiver, hopefully digital,
earth station that could provide wide band receive only and simple
voice communications, 9.6 KHz data transmission, and G-3 two way facsimile
capability for under US $15,000. The earth stations must be
easy to maintain and cost efficient to operate (space segment being
provided by PEACESAT at no cost to the qualified user). This network
would provide basic communications for the remote islands until the
LEO or "Spaceway" style GEO systems are launched and are
affordable to thin route Pacific Island countries of the Federated
States of Micronesia (FSM), the Republic of Palau, and the Republic
of the Marshall Islands (RMI).
2. INTRODUCTION
The University of Guam (UOG) is the
only four year post secondary educational institution located in Micronesia.
UOG offers 26 baccalaureate degrees in four undergraduate colleges:
the College of Arts and Sciences; the College of Agriculture and Life
Science; the College of Business and Public Administration; and the
College of Education. In addition, the UOG Graduate School oversees
the offering of Master's degrees in the areas of art, biology, business,
education, and public administration.
The
student body is relatively diverse. It consists of students from Guam,
Micronesia, the US mainland, the Philippines, and Asia. The present
enrollment is approximately 5,500 students at the main campus. In
addition, the University offers a variety of courses throughout Micronesia
through its Center for Continuing Education and Outreach Programs
(CCEOP).
Micronesia
is about 3,000,000 square miles of ocean (more than 7 million square
kilometers) and 1,045.3 square miles of land (2,707.2 square kilometers).
It runs from 2.39 degrees south to 20.33 degrees north for a maximum
north to south distance of 1,387.2 nautical miles (1,595.28 statute
miles). The east to west distance is approximately 2,726 nautical
miles (3,135 statute miles) lying between 131.10 degrees east and
176.54 degrees east. Thus it covers an area that is roughly equal
to that of the continental United States (See Figure
1 (57 k) ).
Within
Micronesia, UOG has concentrated its efforts on the former American
flag territories. Today, these territories are divided into five separate
political jurisdictions: the Republic of the Marshall Islands and
the Federated States of Micronesia, both of which are freely associated
with the United States; the Commonwealth of the Northern Mariana Islands
and the Unincorporated Territory of Guam, both U.S. Territories; and
the Republic of Palau, the remnant of the Trust Territory of the Pacific
Islands.
3. UOG PEACESAT
The primary role of the UOG
PEACESAT is to provide public service telecommunications to support the Micronesian
educational and medical communities.
As
a regional telecommunications hub, UOG PEACESAT handles most of the
emergency, disaster and medical evacuation traffic in the region.
UOG also delivers college courses and seminars over the PEACESAT network
to the constituents within the three million square miles of Micronesia.
Combining the use of the UOG PEACESAT SSB radio, satellite RF technology,
and distance education program options, the UOG outreach program and
the local community in general have been able to communicate with
the Micronesian region more efficiently and effectively.
Some
of the emergency management users of UOG PEACESAT include the Red
Cross, Federal Emergency Management Agency, Centers for Disease Control,
and the Coast Guard Search and Rescue.
The
FSM Consulate routes medical referral communications to and from Guam
Hospital and FSM Hospitals through the UOG PEACESAT. Telephone interconnections
with SSB, HF radio, and the GOES satellite systems help the FSM states
in their typhoon recovery efforts. The solar powered UOG PEACESAT
was the primary source of information to the outer areas of Micronesia
after the Great Quake on Guam (August 8, 1993). The GOES satellite
and the SSB high frequency radio links connect the most remote reaches
of Micronesia to the developed information centers around the Pacific
Rim.
4.
PEACESAT MICRONET -- DISTANCE EDUCATION MISSION, PROGRAMS, SERVICES,
AND NEEDS.
The
UOG PEACESAT provides public service, distance education and Internet
via satellite to Palau, Majuro, and the four emerging island states
of FSM and their respective outer islands of Micronesia. The UOG PEACESAT
also established and continues to operate a HF/SSB network that reaches
dozens of outer island schools and dispensaries within Micronesia.
UOG services provided to the region include:
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MICRONET
news and weather (international and regional) are broadcast daily
from Guam, often directly into the local island's AM station. |
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UOG
provides UOG College of Education courses to Rota (Commonwealth
of the Northern Mariana Islands, CNMI), the four states in the
FSM, the Republic of the Marshall Islands, and the Republic of
Palau. Most courses are live interactive voice or on-site video
with PEACESAT interactive voice lectures. |
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The
UOG College of Nursing is currently providing interactive digitized
compressed video, electronic whiteboard and digital voice over
standard voice grade circuit to Palauan nurses. This exciting
new distance education delivery technology is currently run over
a Macintosh format and is interactive with Palau Community College.
We would like to expand this service to other entities and organizations.
Courses will use land line modem connections for color digital
transfers combined with standard lectures that are delivered over
PEACESAT voice circuits. The College of Nursing and the Palau
nursing students produced short videos and exchange them via Continental
pouch. |
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The
UOG College of Nursing is currently providing interactive digitized
compressed video, electronic whiteboard and digital voice over
standard voice grade circuit to Palauan nurses. This exciting
new distance education delivery technology is currently run over
a Macintosh format and is interactive with Palau Community College.
We would like to expand this service to other entities and organizations.
Courses will use land line modem connections for color digital
transfers combined with standard lectures that are delivered over
PEACESAT voice circuits. The College of Nursing and the Palau
nursing students produced short videos and exchange them via Continental
pouch. |
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All
Distance Education services are supported by the UOG9 UNIX Internet
Services combined with facsimile and modem connectivity provided
through the PEACESAT system. R&D continues on Packet/duplex/ethernet
extensions over to interface with the proposed PEACESAT Services
Improvement Plan (SIP) that will provide enhanceddigitized audio-video
graphics for superior distance education programming. Also, Guam
is currently seeking funds for training workshops and technical
development upgrade projects that will support all of the Micronesian
sites.
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5.
COMMUNICATIONS NEEDS IN THE REMOTE ISLANDS
UOG
PEACESAT has been, and continues to be, committed to providing services
to the Micronesian region. Unfortunately, the current communication
environment does not allow UOG to provide support to the outer islands.
The
remote islands, as stated earlier, are not served by the telecommunication
carriers within the region. The majority of the population base in
Chuuk, Pohnpei, Yap and the Marshall Islands are not in the centers
and are generally without any communication links to the children
and professionals in the schools and dispensary facilities.
There are no Intelsat or PEACESAT earth stations at these remote sites.
The location of Intelsat earth stations on these islands have not
yet been deemed cost effective by carriers. Further, the current PEACESAT
earth stations are not configured to enable UOG PEACESAT to provide
the kind of services that it is prepared to support in the remote
islands of Micronesia.
The current PEACESAT earth stations support a single carrier that
can be used for voice or for data, but are not designed for receiving
compressed digital video at base speeds of 128 Kbps. The current PEACESAT
stations are also more expensive ($35,000 with autotracker) than is
possible for many of these small islands to purchase.
Consequently, these remote islands only have HF and SSB communications
that are not fully reliable. There is a very strong need in Micronesia
for the development of a small, robust, marine grade narrow-band earth
station that works in conjunction with the PEACESAT system.
6.
GENERAL APPROACH TO A LOW COST EDUCATION/MEDICAL SATELLITE DELIVERY
SYSTEM IN MICRONESIA
The
following vision is an effective, efficient, appropriate and cost
effective scenario to provide distance education and teacher training
curriculum communication links to the underserved population centers
in the outer islands of the emerging island nations of Republic of
Palau, FSM, and the Republic of the Marshall Islands.
The vision is based on the use of the PEACESAT GOES-2 satellite. The
same scenario with proper hardware changes could use a commercial
C-Band or Ku band space segment. However, PEACESAT is appropriate
for distance education and medical conferencing as long as the traffic
is limited to non profit communications.
Currently, the PEACESAT Services Improvement Plan proposes to upgrade
specific sites to 6 meter digital earth stations (Okamura and Mukaida,
1995, 1994) with wide bandwidth capability. This scenario is fine
for government centers such as Kolonia, Pohnpei, Koror, Palau, Kwajalein/Ebeye
area of the Republic of the Marshall Islands, Garapan, Common wealth
of the Northern Mariana Islands, and the University of Guam where
a high volume traffic conduit is needed.
However, the large earth stations will cost up wards of U.S. $250,000
each and will commit the hosting government agency to a recurring
maintenance and personnel cost. For the outer islands of the FSM and
the Republic of the Marshall Islands, we hope that smaller, more appropriate
systems can be installed for 1/10th of the cost of a 6m earth station
and serve as a complement to the PEACESAT Hub Site network.
Commercial links will not be cost effective in these outer islands
until LEO's or super GEO wide area satellite phone exchanges are launched
and implemented sometime after the turn of the century. With over
3 million square miles of ocean, only SSB/HF radio and satellite networks
may be cost effective within the region in the near future. However,
we are still not sure that the final cost of these new LEOs and GEOs
will be cost effective for the outer islands in the region.
7.
FUNCTIONAL CONCEPT OF A DIGITAL VIDEO RECEIVE WITH VOICE OR DATA RETURN
The
basic concept is to install and maintain a small learning resource
center in the more populated outer islands. Each class room would
be supplied with solar powered circuits with generator back up for
the audio-video computer integrated earth station. All equipment would
be DC input (12VDC VCR/ Monitors and computers are currently available),
and simple to operate and maintain.
The earth stations would be small, digital and capable of up &
down linking of 9.6 Kbps with 128 Kbps digital video receive capability.
The concept assumes that power required for wide bandwidth transmit
capability would not be cost effective and therefore not sustainable.
The wider bandwidth receive link would allow the remote site to receive
compressed color video from the originating up link facility in Guam,
Saipan, Pohnpei, Hawaii, etc. A PC based, low speed video codec system
would be used for receiving programs.
Full G-3 fax and phone links will be available along with Internet
access and basically any communication device that is compatible with
a phone system that can be hung on the earth station. The earth stations
need not have more than 2 simplex (multiple site teleconferencing)
channels and one duplex channel. The VCR system can show the prerecorded
class tapes, and the remote classroom can interact via the satellite
link. The earth stations can be installed for under U.S. $20,000 each
and with local support can be operated inexpensively thanks to the
U.S. supported GOES space segment.
In addition to the educational services a grant would fund, emergency
links will utilize the 'earth alert' hand held triggered from UOG
via satellite. When islanders receive an alert from UOG, they will
check the SSB for details from Guam. UOG can design low powered FM
broadcast stations that can be used for distance education, cultural
programs, primary health care workshops, and would be available for
emergency information dissemination for Tsunami/typhoon locations,
search and rescue, etc. This scenario allows small $10 transistor
radios to be at the homes for monitoring the local atoll's solar powered
FM broadcast station, which can be fed to UOG PEACESAT Communications
Hub during emergencies or distance education programming.
Figures
2 and 3 contains a general pictorial representation of this vision.
Figure 2 (55 k) shows how the system would be
interfaced to existing HF and AM systems, as well as to emergency
notification system such as Earth Alert, currently being tested by
NASA.
Figure
3 (58 k)shows an inexpensive
6m mesh antenna to receive digital video and have a data or voice
return based on digital compression technologies. The figure illustrates
the conceptual application needs of UOG PEACESAT, but does not need
to be implemented with this specific technology. Figure 3 also shows
the existing PEACESAT 3m sites as participating in network through
64 Kbps digital modems. The key is not the technology that is identified
but the ability to meet requirements that are generally outlined below.
8.
SYSTEM REQUIREMENTS
The
following are some of the requirements and parameters of the system.
7.1. GOES-2 Satellite Environment
PEACESAT uses the second of a series of Geostationary Observation
Environmental Satellite or GOES-2. The GOES-2 satellite is in an inclined
orbit to save fuel and located at 175oW. This inclined orbit requires
any system accessing the satellite to constantly track its movement
through a figure eight. The nominal satellite position dimensions
in the Year 2000 consist of:
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North-South
+/- 15.0o |
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East-West
+/- 2.0 o |
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8.1.1.
The satellite link budget, based on the best available information,
is: |
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Beam
center EIRP 54.4 dBm |
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Downlink
beamwidth 19.6 o |
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Earth
edge 2.4 dBm |
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Earth
edge EIRP 52.0 dBm |
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Multicarrier
EIRP 52.0 dBm |
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Transmit
EIRP 35.4 dBm |
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Transmit
EIRP Stability +/- 1 dBm |
8.1.2. The system has a hard limited repeater and operates in multicarrier
mode. There must not be any interference or intermodulation impacts
to the existing carriers.
8.1.3. All performance measures must conform with the existing PEACESAT
frequency and carrier plan.
8.1.4. The azimuth of the earth station must be plus or minus 25 degrees.
The GOES-2 has a global footprint. Earth stations are located in Palau,
Papua New Guinea, Australia, and Oregon. All must be able to see the
GOES-2 in its current location.
8.1.5. The earth station must have a dual axis auto tracker to optimize
on performance and minimize the level of operator intervention.
8.1.6. The tracking system must be compatible with the existing beacon
receiver signal.
8.1.7. The operational frequencies for the GOES-2 satellite are as
follows:
Transmit: 2025-2034 MHz
Receive: 1683-1695 MHz
8.2. Cost
The proposed system should cost about $15,000. This does not include
the cost of the digital video receive only codec, microcomputer, or
other peripheral equipment.
8.3. Environmental Requirements
The Pacific island countries present several problems that must be
accounted for in the design. The earth station requirements include
design consideration of the following environmental conditions or
restraints.
8.3.1. The system must be able to operate with heat and humidity.
8.3.2. The system must be resistant to salt water that corrodes metal.
8.3.3. The system must minimize the electronic components that would
be outside of a building.
8.3.4. Outdoor components must be protected and replaceable in the
field.
8.3.5. The antenna must have a survival wind speed of 125 miles per
hour.
8.3.6. The antenna must be capable of operating in winds gusting to
60 miles per hour.
8.3.7. The tracking system must have memory and renewals, and the
use of a single step tracking capability.
8.4. Appropriate Technology
8.4.1. The system must be designed to use as much off the shelf low
technology as possible that can be installed, operated, and repaired
by electronics technicians.
8.4.2. The design must be based on field replaceable components to
minimize the repair and maintenance problems created by the vast distances
in the Pacific and the high costs of transportation and time.
8.4.3. The design of the earth stations must enable technicians in
the field to diagnose problems without expensive test equipment.
8.4.4. Direct power must be used to interface with solar power batteries.
8.5. Functional System
8.5.1. The system must be able to transmit voice or data and receive
digital video signals.
8.5.2 The system must be able to transmit data through multiple access
channels.
8.5.3. The system must have the teleconferencing capabilities of a
simplex channel.
8.5.4. The system must be able to interface with the existing PEACESAT
analog simplex channels.
8.5.5. The system must be able to receive a compressed digital video
receive only signal through the QPSK digital modulation that PEACESAT
uses.
8.5.6 The system must be able to support phone patching through the
PSTN.
8.5.7 The system must have standard audio interfaces for microphones
and for speakers.
8.6. Technology
8.6.1. The system must support widely used component parts that will
not be discontinued.
8.6.2. The system must have a high reliability under the conditions
specified above.
9.
SUMMARY
The
outer islands of Micronesia are not well served despite similar needs
for medical and educational uses of telecommunications as the main
islands. Today, the outer islands are only served via HF or SSB radio
links. These links are unreliable.
We are hoping that it might be possible for industry or an international
funding organization to assist in the development of a system that
would enable these outer islands to receive some of the programming
that will be provided by the UOG and other PEACESAT Hub Sites in the
Pacific Islands region. The programming would consist of voice teleconferencing,
data and other information access, and the ability to receive compressed
digital video at 128 Kbps.
In doing so, we will take a step toward ensuring that small island
communities will be able to participate in the benefits of the revolution
in telecommunications and information technology, services, and programs.
BIBLIOGRAPHY
Okamura,
N. and L. Mukaida (1995, September) "Public Service Telecommunications:
PEACESAT," Pacific Telecommunications Review, 14-23.
PEACESAT Headquarters, Hub Site Request for Proposals, November
14, 1994.
Okamura,
N. & Mukaida L. (1994) "PEACESAT: A Regional Telecommunications
Alliance in Transition," Proceedings of the Pacific Telecommunications
Conference '94, 811-819.
ENDNOTES
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The
opinions and the interpretations in this paper are those of the
authors and do not necessarily represent, nor do they purport
to represent, the views, opinions, or the work programs of PEACESAT
- Headquarters. |
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The
idea of a digital video receive system was developed by PEACESAT
as part of its "Services Improvement Plan." Unfortunately,
it has not been developed given fundinglimitations. |
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The authors would like to acknowledge the assistance of Dr. Norman
Okamura, Associate Specialist, Social Science Research Institute,
University of Hawaii, in contributing to some of these specifications.
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