VSAT in 30 Minutes
Short Description
VSAT...
Description
VSAT in 30 minutes
Satellite
Types of Orbit Inclined Orbit
Polar Orbit
Equator
What does Geostationary mean? • Geo = Earth, Stationary = Not Moving • Satellite is a Fixed Point in the Sky • Rotation of the Satellite = Rotation of the Earth (~24 Hrs/Rot) • Equatorial Plane (only possible orbit) • 35,786 km above the Earth’s surface (only possible distance)
Equatorial Orbit
Satellite – Main Subsystems Antenna Payload Communication Spacecraft Control/Propulsion
Electrical Power ce tan s i D age r e Av : arth E o t S/C 786 km , 35
Earth
Satellite
M from
oo
E n to
art
m 92 k 3 , 4 8 h: 3
GEO lifetime: > 15 Years MEO lifetime: ~ 15 Years LEO lifetime: 5 - 7 Years
Moon
Frequency (Spectrum)
Satellite/Transponder Bandwidth •
Satellite Capacities are
• 500 MHz Vertical Polarization • 500 MHz Horizontal Polarization • Divided into bands using Transponders •
Ku Band
• 14000 MHz to 14500 MHz (Uplink) • 11700 MHz to 12200 MHz (Downlink) • Guard Band 2 MHz
Guard Band • 4 MHz
Transponder Bandwidth is generally one of following: 27 MHz, 36 MHz, 54 MHz, 72 MHz Transponder Transponders for Vertical and Horizontal Polarization Bandwidth 36 MHz
Transponder Horizontal
Vertical
36 MHz
36 MHz
36 MHz
36 MHz
36 MHz
1
3
5
7
9
36 MHz
11 …
36 MHz
36 MHz
36 MHz
36 MHz
36 MHz
2
4
6
8
10
MHz 14000 Vertical Transponder is centered on Guard Band of Horizontal
Guard Band 2 MHz
36 MHz
12 … 14500
Linear Polarization
VSAT Feed Assembly & Installation
BUC
BUC LNB OMT Orthogonal
Block Up Converter Low Noise Block (Down Converter) Orthogonal Mode Transducer Relating to or composed of right angles. Having a set of mutually perpendicular axes
Cross Polarization (XPol) Cross Polarization
Satellite
r Ho
tic al
Uplink and Downlink Use different polarization
Ho r
al tic
iz on ta l
Ve r
l ta on iz r Ve
Coincident Polarization (CoPol) Co Polarization
Satellite
tic al
l ta on iz
Ve r
r Ho
l ta on iz
Ve r
r Ho
tic al
Uplink and Downlink Use same polarization
Circular Polarization • Satellite Capabilities are 500 MHz for each Polarization (Right and Left)
Right Hand Circular Polarization
Left Hand Circular Polarization
Antennas (not aerial or antennaes, antenni)
All the angles Elevation [ ° ]
N Azimuth [ ° ]
0 550 > 10°
Look angle to satellite
Parabolic Antenna
Power X
= EIRP
Offset antenna is oval and has the feed locate below the lower edge of the reflector • Elevation is less than that of a prime focus • Feed horn doesn’t block the aperture
Prime focus antenna is round and has the focal point directly in front of the antenna
What Is a VSAT? Very Small Aperture Terminal (VSAT) User’s LAN or any IP Device Outdoor Unit (ODU)
Indoor Unit (IDU)
LNB + BUC Video iDirect Satellite Router
Ethernet Switch (optional)
Computers
Antenna
VoIP Phones
Point-to-Point Topology
Remote 1 Remote 2
Typical Characteristics:
No Hub – no management or central control Midsize Antenna Expensive Remotes Small Networks
Star Topology Remote 2 Remote 1
Remote n
Hub Typical Characteristics: Expensive Hub Big Hub Antenna Cheap Remotes Small ODU at Remotes Large Networks
Mesh Topology Hub
Remote 1
Remote n
Typical Characteristics: Cheap Hub Expensive Remotes Big ODU at Remotes Small Networks
Remote 2
Remote 3
Multi-Star Topology Mini Hub
Mini Hub
Main Hub Mini Hub
Typical Characteristics:
Often Mistaken for Mesh Moderate Mini Hub Antennas Affordable Mini Hubs Cheap Remotes Small ODU at Remotes Many Private Networks
Mini Hub
Remotes Remotes
Hybrid Topology Star Remotes
Mesh Remotes Mini Hub Mini Hub
Star Remotes
Main Hub
Mini Hub
Typical Characteristics: Extremely hard to manage Seldom implemented
Mini Hub
Mesh Remotes
Mesh Remotes
A VSAT System SCPC Connection
C or KuKu-Band Satellite
By simply adding a separate line card, the iDirect solution can support different topologies from the same chassis It can also support multiple satellite links
The new iDirect Hub Chassis Line Card supports network speeds of 18 Mbps Downstream, and 4.2 Mbps Upstream. A single 20 slot Hub Chassis supports aggregate speeds of 360 Mbps.
Network Operator Teleport
SCPC Topology
iDirect Broadband VSAT Hub
Star Connection
Mesh Connection
Star Topology
Internet/ Leased Line/MPLS
iDirect Satellite Router Star/Mesh Topology
iDirect's Broadband VSAT Network System Provides Highly Reliable, Reliable, Secure, TwoTwo-way TCP/IP Transmission for High Speed, MultiMulti-media Service Applications on any Topology (Star, Star/Mesh, Point Point--toto-Point/SCPC)
The Radio Frequency (RF) Trade Space • Each finite amount of information takes 3 resources to transmit. • Power (EIRP in Watts) • Bandwidth (Spectrum in Hz) • Time (Speed in bits per second)
• Satellite systems engineering is largely about finding the least expensive combination of resources in any given scenario. • More of each resource means less of the other 2 resources. • This trade-off must be analyzed in space and on the ground.
EIRP and G/T • EIRP – Effective Isotropic Radiated Power • A measure of the amount of power a transmitter puts out. • It costs more money to put out more EIRP. • More powerful signals are easier and less expensive to receive. • These financial guidelines apply on the satellite and on the ground.
• G/T – Gain over Temperature • A measure of how sensitive a receiver is to a signal’s power. • It costs more money to hear weaker signals. • The better your hearing, the less signal strength and the less bandwidth you need to receive each bit.
Modulation • Modulation – Digital to Analog Conversion (easy) • Demodulation – Analog to Digital Conversion (hard) • Symbol – A change in an analog wave (Note: 1 symbol takes at least 1 Hz) • Amplitude • Frequency • Phase
• Phase Shift Keying (m-ary PSK) • • • • • •
BPSK is phase changes in multiples of 180° (1 bits per symbol) QPSK is phase changes in multiples of 90° (2 bits per symbol) 8PSK is phase changes in multiples of 45° (3 bits per symbol) iDirect normally uses QPSK Higher order modulation squeezes more bits into each Hz More Hz cost more money
Forward Error Correction (FEC) • Encoding – Adding extra bits to make sure that content is accurate even when not all the bits arrive accurately. • X bits of content need to be sent • Y bits of overhead are added to guarantee the integrity of the X bits • B bits are actually sent over the air
• B has the same number of bits as X + Y put together • But B is a transform of X, not the sum of X + Y • FEC Rate is a ratio: information bits ÷ bits sent over the air • • • • •
Rate ½ is 50% efficient encoding Rate 0.66 is 66% efficient encoding Rate 0.793 is 79.3% efficient encoding Higher FEC rates typically require more power to implement More power costs more money
RSV, TPC, and LDPC Encoding • RSV – Reed-Solomon/Viterbi Codes • Encoding method used in DVB-S industry standard • Not computationally intensive, but consumes much power
• TPC – Turbo Product Codes • Encoding method used by iDirect • Computationally intensive, but consumes less power
• LDPC – low density parity check Codes • Encoding method used in DVB-S2 industry standard • Very computationally intensive, but consumes least power possible
• Less power means… • Smaller (cheaper) remote terminal antennas and/or • Higher FEC rate for greater bandwidth efficiency and/or • Higher order modulation for greater bandwidth efficiency
Multiple Access Schemes • Multiple Access – How multiple remotes talk to 1 hub. • Analogous to cars at an intersection.
• TDMA (time division multiple access) assigns time slots for each carrier/frequency. There are 2 versions of TDMA: • Random access aka slotted Aloha • Reservation access aka Deterministic-TDMA
• Most TDMA VSAT use random access to carry bursty traffic and reservation access to carry continuous traffic. • Slotted Aloha leaves 80% of available capacity unused to so that 80% of all upstream transmissions get through 80% of the time. • Slotted Aloha retransmits the 20% of bursts that collide.
• iDirect uses reservation access to carry all traffic. • D-TDMA uses all available capacity all the time to carry traffic. • D-TDMA has no collisions and thus require few retransmissions. • D-TDMA is enabled by iDirect’s fast capacity allocation algorithm.
Bandwidth Overhead Structure: From IP throughput to MHz
IP Data Rate Or User Data Rate
TDMA Overhead
Information Rate
Transmission Rate
Symbol Rate
FEC
Mod
Guard Band
0.66 0.793
QPSK
1.2
Mhz
The iDirect Platform and Products
iDirect is the Platform of Choice
End-Customer Requirements Small Enterprise
• Basic IP connectivity • Voice and data and Internet applications • Optimized for remote internet access • Very price sensitive
Large Enterprise
Military
• Support for all • Support for all business applications consisting applications consisting of real-time (VoIP, of real-time (VoIP, videoconferencing) and videoconferencing) and non-real time traffic (data non-real time traffic (data files, web browsing, etc.) files, web browsing, etc.) • Demand for VPN • Requires highest and full encryption security standards (AES capabilities encryption, TRANSEC, FIPS 140-2 certification) • All topologies supported (MF-TDMA star, mesh, iSCPC) • Requires high quality and maximum QoS flexibility
Mobility / COTM
• Requires Spread Spectrum for efficient use with very small antennas • Need for rugged equipment that sustains movement/ vibration • Military additionally requires highest security standards (AES encryption, TRANSEC, FIPS 140-2 certification)
Hub Series Universal 5-IF 20 Slot Hub Universal 4-slot Hub Series 15000 Series 12100
• 11U high, 19” rack mountable • 20 slots , up to 5IF interfaces • TDM / MF D-TDMA, DVB-S2/ACM* • Gigabit Ethernet interface • Supports all line cards
• 5U high, 19” rack mountable • 4 slots, up to 4IF interfaces • TDM / MF D-TDMA, DVB-S2/ACM* • Gigabit Ethernet interface • Supports all line cards • Optional OPM • RCM modules • Management Control Module (MCM)
Model
Star
Mesh
SCPC
Model
Star
Mesh
SCPC
15052
X
X
X
12102
X
X
X
Mini Hub Series 10000
iSCPC Concentrator
• 2U 19” rack mountable • One slot, 1IF hub • One in-/ outbound network capability • 10/100 LAN interface • Star, mesh, SCPC
Model Star Mesh SCPC
• 11U high, 19” rack mountable • 20 slots • Up to 5IF interfaces • Gigabit Ethernet interface • SCPC line cards only • IP data rates of up to 20 Mbps each link
Size
Model
10315
X
X
X
15 users
15051
10330
X
X
X
30 users
Star
Mesh
SCPC X
iNFINITI Satellite Routers iNFINITI 3000*
Small Enterprise Entry Level – Optimized for Internet Access, Basic Voice and Video • • • • • •
Adaptive Channel Compression Application QoS TCP Optimization Star Mode Only Optional AES encryption
Model
Star Mesh SCPC Security
iNFINITI 5000
iNFINITI 7000*
iNFINITI 8000
Med/ Large Enterprise
Military
Military and COTM
Supports business critical applications
Advanced performance remote networking
Most advanced performance remote networking
Same features as 3000 model , plus…
Same features as 5000 model, plus…
Same features as 7000 model, plus…
• 8-Port LAN Switch • AES Link Encryption (Opt) • Mesh Mode (Opt), SCPC Mode
• TRANSEC Security • FIPS 140-2 certified • AES Link Encryption embedded
• Spread Spectrum waveform • Ruggedized for extreme temperature conditions
Model Star
Mesh
SCPC Security
3100
X
5100
X
X
3100-NB
X
5150
X
X
5300
X
X
X
5350
X
X
X
Model Star Mesh SCPC Security 7350
X
X
X
X
Model 8350
Star COTM SCPC Security X
X
X
X X
* iNFINITI 3000 and 7000 are also available in iConnex mode (circuit boards without enclosures)
X
iNFINITI Router Features • Throughput Rates • Carrier Symbol rates: Outbound up to 15 Msps, inbound up to 7Msps • IP Data Rates: Outbound up to 20 Mbps, inbound up to 6.5 Mbps • Proprietary TDM, MF D-TDMA
• Modulation and Coding • BPSK, QPSK, 8PSK • FEC code rates supported: 0.431 – 0.879 • Eb/No range: 3.9 – 7.9dB
• Protocols and traffic engineering • Extensive range of routing protocols (TCP, UDP,ICMP, IGMP, IRDP,RIP Ver2) • Group QoS, application based QoS, CIR and bandwidth on demand • VLAN tagging
• Features • • • • • •
IP/ router functionality (local DNS caching, DHCP, DHCP helper, NAT (PAT) TCP/IP and Web acceleration, RTTM , cRTP Supports SCPC and mesh AES encryption optional (128-bit or 256-bit) TRANSEC, FIPS140-2 certification optional Spread-spectrum waveforms optional
Evolution Satellite Routers Evolution X3
Mid-Range Enterprise Router
Evolution 8000 Series
Retail / Small Enterprise
Med / Large Enterprise
Military and COTM
Supports business critical applications
Supports high security and mobility
Entry level – Optimized for internet access, basic voice and video • • • •
DVB-S2/ACM Application QoS/ GQoS TCP Optimization Opt. 128 bit AES Encryption
• DVB-S2/ACM or TDM outbound • Application QoS /GQoS • TCP Optimization • 256-bit AES encryption • Supports Spread Spectrum
• DVB-S2/ACM or TDM outbound • Application QoS/ GQoS • TCP Optimization • 256- bit AES encryption • 8-Port LAN Switch • TRANSEC security • FIPS-140-2 certified • Supports Spread Spectrum
Evolution Router Series – New Features • Throughput Rates: • Carrier Symbol rates: up to 45 Msps • IP Data Rates: up to160 Mbit/s • DVB-S2/ACM or iNFINITI outbound; MF D-TDMA inbound
• Modulation and Coding • BPSK (iNFINITI), QPSK, 8PSK, 16APSK • LDPC coding scheme • Adaptive Coding and Modulation (ACM)
• Protocols and traffic engineering
Fully integrated ACM provides over 50% bandwidth efficiency increase
• Extensive range of IP routing protocols • Group QoS, application based QoS, CIR and bandwidth on demand • VLAN tagging
• Features • • • • • •
IP/ router functionality (local DNS caching, DHCP, DHCP helper, NAT (PAT)) TCP/IP and Web acceleration, RTTM, cRTP Supports SCPC and mesh AES encryption optional (256-bit) TRANSEC, FIPS140-2 certification Spread-spectrum waveforms
Thank You Any Questions?
View more...
Comments