Satellite Communications Payload
Design and System Architecture
July 11 - 14
Current and
planned satellite systems for fixed and mobile use now demand an array of
advanced design/analysis techniques and architecture strategies. Developed for
communications engineers, satellite designers and systems architects, this
popular course provides a practical understanding of how modern satellite
payloads (repeater and antennas) and end-to-end systems are designed and
assembled to meet the most demanding service requirements of the private and
government sectors. Design objectives and principles for both analog
“bent-pipe” and digital on-board processing repeaters are investigated. This is
extended to the overall system regarding its architecture, conceptual design, and
ground segment engineering. With a focus on digital narrowband and broadband
applications, the course considers operations in all of the current frequency
allocations: UHF, L, S, C, X, Ku, and Ka bands. The lectures are broken down
into major areas of investigation that allow participants to focus on elements
of a communications satellite payload, satellite constellation and ground
segment, and how they combine into the overall system.
The course begins
from a systems engineering standpoint by identifying the requirements for the
satellite payload, constellation and end-to-end system using current
applications in digital video and broadband media, the Internet protocols and
services, optimized voice communication, and mobile services to land, sea, and
airborne platforms. Requirements of the satellite payload are derived and
specifications reviewed at the input/output and subsystem level. Performance of
all major building blocks is assessed: the repeater and its components, and the
antenna system. Design principles and performance budgets are reviewed for each
element, such as receivers, multiplexers, power amplifiers, analog and digital
processors, reflector and feeds, and phased-array antennas. Critical analysis
concepts, such as loss budgeting, group delay, intermodulation distortion,
digital impairments, cross-polarization, adjacent satellite, and adjacent
channel interference, are covered for the subsystem and system designer. Also
presented are strategies to compile requirements and pursue the spectrum/orbit
resource needed for success.
This course
helps participants to:
·
Understand
how system requirements are transformed into design elements and specifications
for the satellite communications payload
·
Acquire
design skills for configuring a bent-pipe repeater subsystem and the associated
shaped beam antenna
·
Understand
the specific capabilities of different repeater components—low-noise
amplifiers, filters, channel and power amplifiers, and power combiners—that are
critical to meeting overall payload performance requirements
·
Gain
familiarity with the capabilities of digital on-board processing repeaters and
the applications to which they are best suited
·
Understand
overall system architecture and the capabilities of ground segment
elements—earth stations and user terminals—to integrate with the communications
payload on an end-to-end system basis
·
Be
able to describe an overall system that addresses the service requirements and
can be developed using currently available components in space and on the
ground
·
Create
and pursue an effective spectrum/orbit acquisition strategy
In addition
to a thorough review of the satellite payload design process, the ground
segment and overall system are investigated, including requirements for major
earth stations and user terminals to deliver one-way receive services, such as
digital Direct-to-Home (DTH) TV, Digital Audio Radio Service via Satellite
(DARS), and data broadcasting or two-way interactive services using VSAT and
mobile communications technologies. Design tools for link budgets and
end-to-end performance assessment are presented and demonstrated. The course
concludes by considering a practical methodology for evaluating and optimizing
the performance of the overall system. Throughout the course, emphasis is on
design principles using classical mathematical techniques, along with modern
software tools for personal computers. Examples are used extensively and
participants are encouraged to bring along their particular design problems for
consideration in class.
UCLA Extension has
presented this highly successful short course since 2000.
Course Materials
The text, Introduction to Satellite Communication,
Second Edition, B.R. Elbert (Artech House, 1999); and detailed lecture notes
are distributed on the first day of the course. The notes are for participants
only and are not for sale.
Coordinator and Lecturer
Bruce R. Elbert,
MSEE, MBA, President, Application Technology Strategy, Inc., Thousand Oaks,
California; and Adjunct Professor, College of Engineering, University of
Wisconsin, Madison. Mr. Elbert is a recognized satellite expert and has been
involved in the satellite and telecommunications industries for over 30 years.
He founded ATSI to assist major private and public sector organizations that
develop and operate cutting-edge networks using satellite technologies and
services. During 25 years with Hughes Electronics (now the DIRECTV Group), he
directed the design of several major satellite projects, including Palapa A,
UCLA Faculty Representative
Kung Yao, PhD,
Professor, Department of Electrical Engineering, Henry Samueli School of
Engineering and Applied Science
Daily Schedule
Tuesday
Service Requirements for Communications Satellites
Satellite
architectures, generic capabilities of GEO and non-GEO satellites, service
requirements for Bent-Pipe Satellites, digital TV (direct-to-home satellite
broadcasting and DVB systems), telephony (single-channel and multichannel
services), data/VSAT Networks (star and mesh networks), basic operation of the
Internet Protocol over satellite links, mobile services (CDMA and TDMA),
digital audio broadcast via satellite (XM Satellite Radio and Sirius Satellite
Radio), and service requirements for digital processing satellites.
Systems Engineering to Meet Service
Requirements
Characteristics of the space-ground RF link; the appropriate use of link
budgets; network design methodology; analytical system analysis approaches;
collecting and quantifying traffic requirements; basic interference analysis
(antenna sidelobes, carrier to interference ratio, orbit spacing); performing
space segment versus ground segment trades.
Communications Payload Requirements
RF system analysis for the satellite payload; top-level payload
specifications (EIRP, SFD, and G/T); overview of transmission system in terms
of power and gain; digital impairments (Bit Error Rate [BER], Eb/No,
implementation margin); modeling repeaters; antenna concepts; co-polarized
directivity and gain; cross-polarization; estimating antenna gain (basic
antenna formulae and gain-area product).
Wednesday
Bent-Pipe Repeater Design
Transponder design requirements; frequency translation; low-noise
amplification; transponder frequency plan and channelization; power
amplification (linear and limiter/AGC mode operation); bent-pipe payload
architectures; LNAs/downconverters/receivers; input filters and multiplexers;
passive microwave hardware (waveguide components, circulators, directional
couplers, hybrid dividers); beam and channel switching; pre-amplification and
linearization; high-efficiency power amplifiers (TWTA and SSPA); output filters
and multiplexers.
Antenna Configurations and Their
Performance Characteristics
Fixed reflector antennas; feeds and feed systems, movable and
reconfigurable antennas; shaped reflectors; circular and linear polarization
antenna design; dynamic beam forming; detailed antenna characteristics
(polarization purity, surface tolerance, isolation); antenna measurements.
Payload Performance Budgeting
Gain/loss budgets; Saturation Flux Density (SFD); system noise and its
effect on G/T; EIRP optimization; repeater frequency stability and phase noise;
spacecraft pointing; budgeting for channel characteristics and impacts to
baseband signals; gain flatness (amplitude ripple); group delay and its
impairment to digital services; phase shift vs. frequency; out-of-band
rejection (adjacent channel and external); amplitude linearity (C/3IM and
NPR);, passive intermodulation (PIM) and multipaction.
Digital Processor Technology
A/D and D/A conversion, digital signal processing for typical channels and
formats, demodulation-remodulation processing, multiplexing and packet
switching, static and dynamic beam forming, design requirements and service
impacts.
Thursday
Multi-Beam Antennas for Digital
Processing Satellites
Multi-horn reflector antenna systems, elemental phased array systems,
reflector-based phased array, direct radiating arrays, lens antennas, analysis
of beam-to-beam isolation, computer analysis and subsystem testing.
Spectrum and Orbit Requirements
Definition
Review of domestic and international regulatory processes and procedures
(FCC and ITU); choosing frequency bands that best address service needs;
development of regulatory and frequency coordination strategy.
Ground Segment Selection and
Optimization
Overall architecture of the ground segment: centralized versus distributed
networks; classification of ground stations; transponder utilization
principles; providing adequate uplink and downlink margin; selection of the
appropriate antenna size; earth station internal tradeoffs (RF power and EIRP,
receiver noise, and G/T).
RF Analysis of Ground Segment
Requirements
Receive gain and transmit EIRP budgeting; estimating antenna, receiver, and
system noise temperature; low-noise amplification (LNA versus LNB); G/T
budgeting; selection of microwave components.
Teleport Earth Station and Gateway
Design
Developing the top-level specification; RF specifications; baseband
specifications; detailed block diagram; antenna systems (center-fed and offset
parabolic, Cassegrain, tracking systems); transmitter systems (KPA, TWTA, SSPA,
redundancy switching).
Fixed and Mobile User Terminals
User terminal
technology: antenna and SSPA, modem, multiplexing, compression/decompression;
interface to external devices: TV, telephone, PC, terrestrial networks;
considerations for consumer design; transportable and fly-away terminals;
airborne and shipboard designs; personal and handheld user terminal concepts.
Friday
Performance and Capacity Assessment
Performance comparison of multiple access systems: FDMA, TDMA, and CDMA;
analytical models of network performance; satellite capacity sizing and
footprint evaluation; transponder capacity planning; lessons learned in a real
project.
Employing TCP/IP and Internet-Based
Protocols and Applications
Adapting the TCP/IP to the GEO satellite path, acceleration and spoofing to
reduce end-to-end latency, support for emerging Internet applications—video
conferencing (H.323), voice-over IP (VoIP), content distribution and caching,
verifying performance in conjunction with Internet services and applications.
Satellite System Development Methodology
Collect and refine the requirements, survey of available technology and
resources, incorporate the spectrum plan and alternatives, perform tradeoffs to
resolve design issues and develop the most appropriate set of specifications,
oversee design and integration of space and ground elements, verify end- to-end
performance at each stage through delivery, resources and documents to aid in
the process.
Case Study of an Integrated System
System to be selected based on current developments in the industry; review
of each major element, relating it to the design principles of the course;
review of spectrum/regulatory strategy and results; discussion of objectives
versus lessons learned from the project.
For more information call the Short Course Program Office at (310) 825-3344;
fax (310) 206-2815.
Dates July 11 - 14 (Tuesday through Friday)
Time 8
am-5 pm (subject to adjustment after the first class meeting)
Location Room G-33 West,
Reg#
Course No. Engineering 881.238
Units 2.4 CEU (24 hours of instruction)
Fee $1695,
includes course materials
$100 nonrefundable; no refund after July 7, 2006; however, course fee (less
$100) may be applied toward another short course enrollment.
