SkyWAN® Indoor Unit IDU 7000 Series IDU 7000, Software Rel. 7.11 IDU 2570, Software Rel. 7.11 IDU 2070, Software Rel. 7.11 IDU 1070 Series IDU 1070, Software Rel. 1.
ND SatCom Product GmbH Graf-von-Soden-Strasse 88090 Immenstaad Germany Phone: E-Mail: +49 (0)7545 939 0 info@ndsatcom.com This document is protected by copyright law. This document is the property of ND SatCom Product GmbH (hereafter referred to as ’ND SatCom’), which reserves all rights. This document or parts of it may not be reproduced, duplicated or distributed to third parties. Nor may their content be disclosed to third parties without the express written approval of ND SatCom Product GmbH.
MANUAL CONVENTIONS There are a few graphical symbols and formatting conventions used to show information clearly arranged and easy to find. Symbol used for Information Symbol is used to notify a user of special or useful information. i Action Item Action Items are used to direct the user to execute the steps in the given order for a successful completion of the action.
Page intentionally left blank 2 Network Design and Engineering Guide 2010-10-26
TABLE OF CONTENTS Manual Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table of Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.7 Guaranteed Throughput . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36 Guaranteed Throughput Example Scenarios . . . . . . . . . . . . . . . . . . . . Scenario 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scenario 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scenario 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scenario 4 . .
Path Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Saturation Flux Density (SFD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Noise, Figure of Merit G/T and Signal-to-Noise Ratio Eb/No . . . . . . . . Satellite Link Quality Dependencies . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Equivalent Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rain fade. . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 4.2.1 SkyWAN® Internet Protocol Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107 SkyWAN® IP Router Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .107 SkyWAN® IDU 7000 Series Interfaces. . . . . . . . . . . . . . . . . . . . . . . . 109 4.2.2 Basic IP Network Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111 4.2.3 Static Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LIST OF TABLES Table 1-1 SkyWAN® IDU 7000 / 1070 Series Manuals Suite . . . . . . . . . . . . . . . . . . 17 Table 2-1 IP Voice Call Data Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 2-2 Frame Relay Voice Call Data Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 2-3 Summary ’General Data Input’ Parameter. . . . . . . . . . . . . . . . . . . . . . . . . 59 Table 2-4 Summary ’Data Input Per Frequency Channel’ Parameter . . . . . .
Page intentionally left blank 8 Network Design and Engineering Guide 2010-10-26
LIST OF FIGURES Figure 1-1 Overview VSAT Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 1-2 Overview Design and Engineering Process . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 2-1 Carrier Design Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 2-2 SkyWAN® Networking at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 2-3 Voice over SkyWAN® . . . . . . . . . . .
Figure 2-37 Signal Preparation - Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 Figure 2-38 Start integrated SkyNMS TDMA Calculator . . . . . . . . . . . . . . . . . . . . . . . .55 Figure 2-39 TDMA Calculator GUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56 Figure 2-40 TDMA Calculator - two Uplink Populations specified . . . . . . . . . . . . . . . . .57 Figure 2-41 TDAM Calculator - Define different traffic compositions . . . .
Figure 3-33 Scenario 1 - Downlink Footprint. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Figure 3-34 Scenario 1 - Ku-Band Transponder Data . . . . . . . . . . . . . . . . . . . . . . . . 101 Figure 3-35 Scenario 1 - Ku-Band Antenna Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Figure 3-36 Scenarion 1 - 2 Carrier Solution Stations . . . . . . . . . . . . . . . . . . . . . . . . 102 Figure 4-1 SkyWAN® IP Protocol Stack IDU 7000 series . . . . . . . . . . . . .
Page intentionally left blank 12 Network Design and Engineering Guide 2010-10-26
Introduction Summary 1 1.1 INTRODUCTION Summary SkyWAN® is a flexible and versatile VSAT system to establish wide area corporate network infrastructures via satellite for enterprises and governmental institutions, supporting a wide variety of end user business applications. The SkyWAN® Indoor Unit (IDU) is a satellite modem with advanced features. It offers multimedia services (voice, video) and data transport sent with small antennas over transparent satellite transponder frequency channels.
Introduction Manual Content - - Satellite Link and Outdoor Unit Design To perform satellite communication over satellite links with sufficient quality the earth stations have to fulfill specific requirements concerning their transmission power and antenna gain. A proper network design is based on an estimation of the link properties, taking into account parameters of the satellite transponder and of the earth stations.
Introduction SkyWAN® 1.3 Solutions and Benefits SkyWAN® Solutions and Benefits SkyWAN® uses an MF-TDMA system supporting a variety of satellite network topologies (fullymeshed, hybrid, star).
Introduction General Design and Engineering Process 1.4 General Design and Engineering Process The general design process of a SkyWAN® network is an ongoing process starting with compiling the end user requirements. Result is a cost efficient network, fulfilling the service requirements defined. The process may be summarized by the following picture: Figure 1-2 Overview Design and Engineering Process Good requirement engineering is the basis of a well designed network and should not be neglected.
Introduction Related Documents 1.5 Related Documents 1.5.1 SkyWAN® IDU Manuals Suite Your intention is Document Title Document Content to understand features and services of a SkyWAN® IDU and its networking possibilities. SkyWAN® IDU 7000 / 1070 Series System Description Describes the technical concept of a SkyWAN® Satellite Network and its features and applications. Explains the system components and provides a comprehensive technical specification.
Page intentionally left blank 18 Network Design and Engineering Guide 2010-10-26
General Carrier Design Introduction 2 GENERAL CARRIER DESIGN The general principle of the carrier design may be summarized by the following steps, refer to figure 2-1: Figure 2-1 2.1 Carrier Design Steps Introduction Within this chapter we will - introduce the SkyWAN® data and voice networking. introduce the essential SkyWAN® MF-TDMA satellite link layer features. discuss the traffic calculation procedure taking into account the relevant SkyWAN® data and voice networking features.
General Carrier Design Data and Voice Networking Overview Within the task A2 Carrier Design the network efficiency / TDMA overhead will be determined. The average TDMA overhead is 15%. But as the overhead range is between 5% and 30% it will be worth to elaborate and downsize such ’nasty peanuts’. With some experience you can start with a good guess about the carrier sizes and feed the ’SkyWAN® TDMA Calculation Tool’ to prove your guess. 2.
General Carrier Design Data and Voice Networking Overview On the receiving station the whole procedure is reversed: - Demodulation and decoding, Reassembly of fragments into SLL frames, Replacing of SLL by Ethernet headers (for IP packets), Forwarding of Ethernet (or FR frames) over the Ethernet (or serial) port. Voice connections The requirement for data traffic is generally specified in terms of a required data rate.
General Carrier Design Data and Voice Networking Overview Voice Codecs The following tables specify the required data rate per call and direction for both VoIP and VoFR calls using the most popular voice codecs. For the user traffic estimation use the tables below: - For VoIP connections: use columns ’IP Bit rate w/o ROHC’ or ’ROHC Bit rate’ of table 2-1. - For VoFR connections: use columns ’IDU Input Data Rate’ of table 2-2. The columns labelled ’incl.
General Carrier Design Essential 2.3 SkyWAN® Satellite Link Layer Features Essential SkyWAN® Satellite Link Layer Features The following section discusses the essential properties of a satellite link in a SkyWAN® network. A proper understanding of the properties and features is essential for a successful network design. 2.3.1 Figure 2-4 SkyWAN® Network Topologies Network Topologies SkyWAN® networks support any kind of satellite network topology.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Figure 2-5 Data Reception Modes Reception Modes In principle a SkyWAN® station can operate in any kind of topology. However, to be able to communicate with more than two other stations in the network a ’Regular Data Reception’ (RDR) license is required. Hence the peer and hub stations represented in the figure would need an RDR license, whereas the star terminals could run with the default ’Limited Data Reception’ (LDR) license.
General Carrier Design Essential 2.3.2 SkyWAN® Satellite Link Layer Features Master and Slave Functionality In a traditional star network the hub station acts as both, a traffic hub and a network management station. In a fully meshed SkyWAN® network, the traffic hub functionality is not necessary since all stations can reach their peers directly over the satellite link. The network management functionality however is always necessary and is normally provided by the SkyWAN® master station.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features - Time stamps to enable transmission time synchronisation. Feedback to slaves concerning their transmission power settings and frequency offsets. The slave stations use the ranging burst for station registration and initial round trip time (earth station to satellite to earth station) measurement.
General Carrier Design Essential 2.3.3 SkyWAN® Satellite Link Layer Features SkyWAN® MF-TDMA functionality SkyWAN® networks are based on a time division technique on multiple carriers which is called ’Multi-Frequency Time Division Multiple Access’ (MF-TDMA). Up to eight carriers can be defined for one SkyWAN® network. The bandwidth of individual carriers is shared by multiple stations by assigning discrete time slots to each station.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Figure 2-8 TDMA Frame Structure Please note: a ranging slot is allocated only when a station is entering the network. Transmit and Receive Carriers SkyWAN® stations receive data on one or two carriers (e.g. IDU7000 with two demodulator boards) . These carriers are defined by station configuration and are referred to as ’Home Channel One’ and ’Home Channel Two’. i Restriction for master stations: Home Channel One must be carrier 1.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features The following restrictions apply: - Home Channel One of each station must be one of the carriers containing a reference burst. In figure 2-9 only channel 1 and channel 2 could be configured as Home Channel One. - A station cannot transmit simultaneously on two different frequency channels. This is the reason why in a ’column’ of the frame plan there are no duplicated ’colors’.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features TDMA Superframe Another TDMA frame option is the definition of a superframe size. By default (superframe size=1) every station has to transmit a request burst in every frame. In a network with many stations this could consume many base slots on the respective carrier leaving few slots left for data bursts. This effect can be reduced by the superframe mechanism.
General Carrier Design Essential Figure 2-12 2.3.5 SkyWAN® Satellite Link Layer Features Two Uplink Populations with Cross-Strapped Transponder SkyWAN® Reference Burst Modes SkyWAN® networks support three different reference burst modes: - Standard Multiple Reference Burst mode (MRB), Multiple Reference Burst with Dual Uplink Beam (MRB-DUB), No Direct Feedback on Reference Burst with Dual Uplink Beam (NFB-DUB). The characteristics of these modes are outlined lelow.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features A graphical representation of a 3 carrier MRB-DUB network is given in figure 2-13. For both MRB modes, the master stations must be able to receive their own bursts on carrier 1. Figure 2-13 MRB-DUB Frame of a 3 Carrier Network NFB-DUB Mode This is the only mode where the master station does not need to receive its own reference burst. There is only one downlink population for all slave stations.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Despite its numerous limitations NFB-DUB mode is a better choice than MRB-DUB mode if - A single star topology is sufficient, - Master and slave stations are located in different satellite beams interconnected via a cross-strapped transponder.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features having to request the capacity first. This mechanism is only available for non real-time data! Figure 2-16 Free Slot Assignment Ranging Subframe The ranging subframe is a number of consecutive slots allocated to slave stations which are not yet registered in the network. These slots are not permanently assigned for this purpose. If there are no unregistered stations in the network ranging slots can be allocated as dynamic data slots.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features To minimize jitter for real time applications the allocation of stream slots for a station will be done as presented in figure 2-18. Once the capacity is allocated the position of the assigned stream slots in the frame will be maintained. Another feature of streaming capacity allocation is that the capacity will be assigned in a semipermanent way: As long as the real-time service (e.g.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features 2.3.7 Guaranteed Throughput By default every station is treated identically concerning the allocation of capacity. Optionally it is possible to define a guaranteed throughput for specific stations on specific carriers. If requested for, the master must allocate these slots even, if it has to reject requests from other stations.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Scenario 1 Both IDU1 and IDU2 are configured for stream mode Normal. The traffic mix (see figure 2-20) consists of: - A non real-time IP based PC application with a bidirectional bandwidth requirement of 128 kbps between these two stations. Additionally 6 parallel voice calls served by SkyWAN® FAD real-time service should be active between the stations.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Scenario 2 Both IDU1 and IDU2 are configured for stream mode Normal. The traffic mix (see figure 2-21) consists of: - A real-time IP based PC application with a bidirectional bandwidth requirement of 128 kbps between these two stations. Additionally 2 parallel voice calls served by SkyWAN® FAD real-time service should be active between the stations.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Scenario 3 Both IDU1 and IDU2 are configured for stream mode Stream within Guaranteed Throughput. The traffic mix (see figure 2-22) consists of: - A non real-time IP based PC application with a bidirectional bandwidth requirement of 128 kbps between these two stations. Additionally 3 parallel voice calls served by SkyWAN® FAD real-time service should be active between the stations.
General Carrier Design Essential SkyWAN® Satellite Link Layer Features Scenario 4 Both IDU1 and IDU2 are configured for stream mode Stream within Guaranteed Throughput. The traffic mix (see figure 2-23) consists of: - A real-time IP based PC application with a bidirectional bandwidth requirement of 128 kbps between these two stations. Additionally 2 parallel voice calls served by SkyWAN® FAD real-time service should be active between the stations.
General Carrier Design Network Traffic Estimation For all scenarios this reduced flexibility only applies to real-time bandwidth served by streaming slots. For non real-time services the master can allocate any unused slot to any requesting station even if this slot is located within the private bandwidth pool of another station. i 2.4 Network Traffic Estimation The starting point for a satellite network configuration is an evaluation of customer requirements.
General Carrier Design Network Traffic Estimation Voice traffic has in principle the same nature as real-time data traffic. However it has a few characteristics requiring a different treatment concerning the traffic estimation: - Individual voice calls consume a relative low bandwidth, but there are many simultaneous calls possible. The voice capacity (streaming capacity) is not constantly in use. A certain amount of blocked calls due to insufficient network capacity is acceptable.
General Carrier Design Network Traffic Estimation Figure 2-25 Traffic Estimation Scenario Fame RelayTraffic The traffic patterns show a network which basically constitutes a double-hub star network. Keep in mind that the real network topology might still be partially or fully meshed. For the traffic estimation in most cases it is enough to consider the most important traffic flows.
General Carrier Design Network Traffic Estimation 2.4.1 Capacity Calculation Tool To calculate the traffic requirement for the whole network a spreadsheet like the ’ND SatCom Academy Capacity Calculator’ may be used which will be presented in the following pages. The capacity calculator is an Excel tool which consists of several worksheets: - Capacity calculation Erlang calculation sheet Voice traffic sheet Carrier configuration TDMA calculator input.
General Carrier Design Network Traffic Estimation quirement is as follows: Two bidirectional video conferences with 256 kbps per direction should be simultaneously possible in the network. Each conference should be set up between one head office (type 1 station) and one small site (type 4 station). The assignment of 256 kbps for each station of type 1 is still correct.
General Carrier Design Network Traffic Estimation higher than the acceptable value, the number of voice channels has to be incremented until the blocking probability fulfils the requirement. In the example figure 2-28, 51 voice channels are required to achieve a blocking probability below 1.5%. Figure 2-28 i Traffic Calculation Example - Erlang B Worksheet Generally the number of users is derived from the number of voice interfaces in the network.
General Carrier Design Network Traffic Estimation a specific carrier, i.e. how many stations have this carrier configured as their home channel. The traffic requirement for this carrier can be derived by adding up the station traffic requirements of all stations assigned to this carrier. Voice Traffic Flow Worksheet The Erlang B calculation estimates the voice traffic for the whole network. To break this down to individual stations, an assumption concerning the traffic flows in the network must be made.
General Carrier Design Network Traffic Estimation Figure 2-30 Traffic Calculation Example - Carrier Configuration Worksheet Note that a general restriction is that master stations must be assigned to carrier 1. In star topology networks the hub station must be assigned to a different carrier than the star terminals. In many cases the optimal station distribution for a multi carrier solution is generating carriers with almost equal data rate requirements.
General Carrier Design Network Traffic Estimation Figure 2-31 Traffic Calculation Example - Carrier Config. with Network Traffic For the two carrier solution the 512 kbps real-time bandwidth must be allocated to carrier 2 because the small sites (station type 4) are all assigned to this carrier. For the three carrier solution the small sites are divided in two subgroups, one is using carrier 2 and the other carrier 3.
General Carrier Design Network Traffic Estimation timate data requirements in transmit direction separately. This argument holds as long as the transmission of data is evenly distributed among the stations, which is typically the case for a meshed network. It may not be valid however, if the transmission is concentrated on few or only one station, like in the case of a single hub star network.
General Carrier Design From User Traffic to Satellite Link Carriers 2.5 From User Traffic to Satellite Link Carriers After the estimation of the required user data rate per carrier, the calculation of the respective bandwidth on the satellite link must consider the following (refer to the steps in procedure description below): - Step 1 and 2: Encapsulation of IP and Frame Relay packets on the satellite link layer . - Step 3: Added redundancy bits for Forward Error Correction (FEC) functionality.
General Carrier Design From User Traffic to Satellite Link Carriers Figure 2-33 Gross Container Information Content 3. So far we have determined the information content of a gross container. This information is protected by adding redundancy bits which allow the receiver to detect and correct a certain ratio of bit errors generated during the transmission over the satellite link. This procedure is called “Forward Error Correction” (FEC).
General Carrier Design From User Traffic to Satellite Link Carriers Figure 2-35 Modulated Gross Container 6. Not all timeslots carry bursts which have been constructed from user data. Depending on the reference burst mode (see chapter 2.3.3 “SkyWAN® MF-TDMA”) some carriers include reference or request bursts. These signaling time slots do require a part of the carriers bandwidth but do not contribute to the user traffic capacity of the carrier.
General Carrier Design From User Traffic to Satellite Link Carriers Generally a selection of 0.2 for the roll-off factor will save bandwidth on the satellite transponder. Smaller roll-off factors mean increased signal power ripples in the time domain which might pose a problem if transmitters on the earth stations or the satellite are operated close to the saturation power level. In these cases a higher roll-off factor may be necessary. 2.5.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ 2.6 TDMA Carrier Design with ’TDMA Calculator’ As outlined in the previous section, the calculation of the required frequency bandwidth of SkyWAN® carriers for an estimated user data rate must take into account - the contributions of the satellite link layer, - the modulation scheme, - the modem overhead.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ The GUI is providing one main screen for general parameter (left hand) and channel specific parameter (right hand), each with an input and an output are. The input parameter section specifies the values to use; in the output parameter section the results are shown after a calculation is performed. Figure 2-39 1Input TDMA Calculator GUI sections marked red. displays integrated SkyNMS TDMA Calculator.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ 2.6.1 Section ’General Data Input’ The parameters in the fields of the ’General Data Input’ section have the following meaning: ’Minimum TDMA frame time’: Fill in the target value for the TDMA frame time, i.e. the time interval between two reference bursts. The SkyWAN® system will automatically select the number of time slots such that the actual TDMA frame time (see also chapter 2.6.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ ’Roll-off factor’: Minimum distance between two SkyWAN® carriers. This value is used to calculate the frequency bandwidth of a carrier: frequency bandwidth = symbol rate * (1 + roll-off factor). 2.6.1.1 Parameter Summary Parameter Name Definition Minimum TDMA frame time [ms] In a SkyWAN network the master sends control communication (e.g. capacity allocation) to slave stations within the reference burst.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ Parameter Name Definition Number of downlink populations Master stations transmits TDMA and network information in the reference burst to all stations on a defined carrier. All stations receiving the reference burst on the same carrier belong to the same 'Downlink Population (DPL)'. Max. quantity of stations configured in one DL is 255.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ ’% of User Data Rate’ must be defined. In the case of ’1- FR voice’, select the FAD voice codec to get the packet length automatically. The same is due for the ’4-VoIP’ field: select the VoIP codec and get the predefined packet length automatically. Additionally it is possible to select entry 'Custom', if a user defined average packet length for VoIP shall be used.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ Parameter Name Definition Modem data rate [kbit/s] Type in the information rate, excluding error correction bits and synchronization patterns for the given channel. Type in for each channel. Modulation scheme Select the modulation scheme for each channel: QPSK, 8PSK. Code rate Select the Forward Error Correction code rate for each channel BER Select the maximum acceptable bit error rate (BER) for this channel.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ Parameter Name Definition (Time slot sizing) ruled by Select '1' The base gross container size and slot time factor is defined in that way that the resulting data rate per slot assignment will support the transport of one or multiple Frame Relay voice calls per slot.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ Parameter Name Definition Length base gross container [byte] Displays the size of the base gross container of channel 1 with data slot length = 1, optimized for the specified traffic. Traffic is sent over satellite in coded gross container packages. A base gross container holds the traffic data plus some overhead (e.g. TDMA header, SLL header, signalling bursts ) before adding the Forward Error Correction (FEC) bits.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ For the definition of the user data refer to chapter 2.5. The spectral efficiency is represented by two definitions: - Efficiency per symbol = user data rate / symbol rate. Efficiency per Hz = user data rate / frequency bandwidth. The difference between these definitions is given by the carrier spacing factor.
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ 2.6.4.1 Parameter Summary Parameter Name Definition User data rate [kbit/s] Displays the user data rate for each channel. Symbol rate [kBaud] Displays the symbol rate for each channel. Eb/N0 [dB] Displays required Eb/N0 for the selected modulation scheme, FEC code rate and gross container size for the given channel. Eb/N0 is defined as the ratio of Energy per Bit (Eb) to the Spectral Noise Density (N0).
General Carrier Design TDMA Carrier Design with ’TDMA Calculator’ 2.6.5 Exporting and Importing TDMA Calculator Values Depending on the tool version, there are two differerent ways for exporting/importing the TDMA calculation values: - ’TDMA Calculator’ standalone tool: Select from the main menu ’File’ the entry ’Export’ to create an XML file which contains all input and output parameter. This file can be printed or sent to the network commissioner who applies the values manually.
General Carrier Design From Capacity Estimation to TDMA Structure 2.7 From Capacity Estimation to TDMA Structure In chapter 2.4 the procedures to estimate the user traffic for a SkyWAN® network and for individual SkyWAN® carriers were discussed. The TDMA Calculator tool allows the calculation of a TDMA frame structure which fulfils the estimated requirements and which is optimized for the applications used on the network.
General Carrier Design From Capacity Estimation to TDMA Structure One Carrier Solution Besides the values provided by the Capacity Calculation tool we make the following additional assumptions: - Reference burst mode: MRB. - Frame time min: 109 ms (should lead to an actual frame time close to the target value of 110 ms). - Available Eb/No = 5 dB, max. BER 10-7. - Packet length for IP Real-time: 1500 Byte, IP Non Real-time: 200 Byte.
General Carrier Design From Capacity Estimation to TDMA Structure Figure 2-43 TDMA Calculator with Optimized 1 Carrier Solution Optimized Three Carrier Solution A similar procedure can be used to optimize TDMA frames for multiple carrier solutions. We present here an optimized solution for the 3 carrier network for which the user data rates have also be estimated by the Capacity Calculation presented at the beginning of this section.
General Carrier Design From Capacity Estimation to TDMA Structure supported range of maximal allowed slots on SkyWAN®. Although this smaller slot size will result in a smaller numerical efficiency due to an increased TDMA overhead, the overall network efficiency is typically higher. The reason for this is that stations, which require e.g.
General Carrier Design From Capacity Estimation to TDMA Structure The resulting user data rates for every carrier match the requirements which we have calculated with the capacity calculation sheet before. The available Eb/No for a carrier is actually a quantity which can only be determined by a link budget calculation procedure, which will be explained in the following section of this guide.
Page intentionally left blank 72 Network Design and Engineering Guide 2010-10-26
Outdoor Unit and Satellite Link Design Introduction 3 OUTDOOR UNIT AND SATELLITE LINK DESIGN In the previous chapter ’General Carrier Design’ we discussed how to derive optimized SkyWAN® TDMA carriers from user traffic requirements. In this chapter we discuss how to perform link budget calculation for SkyWAN® networks using the ND Satcom Link Budget tool and how to optimize links and the outdoor equipment of earth stations.
Outdoor Unit and Satellite Link Design Satellite Beam Footprints Calculate Link Budget The satellite transponder parameters together with the results of the TDMA calculation (TDMA carrier modem rates, modulation and channel codings ) allow the calculation of the satellite link budget. The result of this calculation determines the required ODU equipment: Antenna sizes and amplifier power classes.
Outdoor Unit and Satellite Link Design Satellite Beam Footprints The white contour lines represent areas with a specific signal intensity expressed in terms of Equivalent Isotropic Radiated Power [dBW]. The yellow contour lines specify the earth station elevation angle [°]. Figure 3-3 SES World Skies NSS-7 Satellite Spot Beam Footprint Satellite Choice Considerations Let’s assume that we have to design a network with stations in South America and Africa.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation 3.3 Fundamentals of Link Budget Calculation This section is not supposed to be an extensive description of the techniques of link budget calculations. For that purpose we refer to the available text book literature covering this subject. The reader should however have a qualitative understanding how earth station and satellite parameters affect the quality of a satellite link.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation Path Loss Due to the very long distance earth station – satellite (> 36000 km) only a small fraction of the radiated power will be picked up by the receive antenna of the earth station or the satellite. This signal attenuation is called the free space path loss aPath and depends on both the distance and the radiation frequency.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation The required SkyWAN® IDU 7000 Eb/No levels for different carrier modulation and coding values are both contained in the TDMA calculation tool and the SkyWAN® link budget tool. For a brief discussion we have a look at 3 different values for a satellite link with a bit error rate < 10-7, gross container size > 200 Byte: Modulation FEC Rate Eb/No QPSK 1/3 2.4 dB QPSK 6/7 5.6 dB 8PSK 6/7 8.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation bandwidth. As long as the summary PEB for all carriers is still smaller than the summary bandwidth of all carriers, no extra space segment has to be leased for the carriers with high power requirement. Example: Available transponder EIRP: Transponder bandwidth: Required carrier EIRP: -> Carrier PEB: 50 dBW 36 MHz 40 dBW 3.6 MHz For an example we assume the values given above.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation link availability of 99.9% will result in a higher rain margin compared to an availability of only 98%.
Outdoor Unit and Satellite Link Design Fundamentals of Link Budget Calculation Figure 3-6 Attenuation under maximum Rain Fade Condition 1 XT and XS represent the required EIRP for the transmitting earth station and the satellite transponder without rain fade. 2 XR is the minimum Eb/No level for the given carrier modulation and coding.
Outdoor Unit and Satellite Link Design Considerations for SkyWAN® Link Budget Calculations Figure 3-8 Power Conditions with Uplink Power Control Note that a further reduction to the minimum power requirement for clear sky conditions XT is possible but unnecessary. This functionality is generally called “Uplink Power Control (UPC)” and is implemented in SkyWAN® networks as the built-in automatic Transmission Power Control (TPC).
Outdoor Unit and Satellite Link Design Considerations for SkyWAN® Link Budget Calculations ment must be calculated to transmit signals with sufficient quality to all reachable remote stations on their respective home channels. For a master and backup master station this must include all stations in the network because the reference burst has to be sent to every station in the network.
Outdoor Unit and Satellite Link Design Considerations for SkyWAN® Link Budget Calculations In a SkyWAN® network the maximum possible modulation and coding of a carrier will be determined by the weakest station within a downlink population, i.e. the station with the lowest Eb/No. This weak station may considerably decrease the possible coding efficiency for a carrier which leads to an increased bandwidth requirement for the network.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool If it is not feasible to equip every station using a specific carrier for transmission with an outdoor unit which produces a sufficient large EIRP to reach the maximum IPFD on the satellite, the satellite transponder will also transmit this carrier with an EIRP which is lower than the satellite EIRPmax.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool 3.5.1 Satellite Data Worksheets (Ku- and C-Band) The tool contains a satellite data sheets for defining C-Band and Ku-Band transponder. Figure 3-11 Link Budget Tool - Satellite Data Worksheet(s) For C-Band transponders the link polarization (circular/linear/unknown) must be specified, whereas the for Ku-Band linear polarization is assumed.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool 3.5.2 Antenna Data Worksheets (Ku- and C-Band) The tool contains antenna data sheets for antennas in C-Band and Ku-Band. Figure 3-12 Link Budget Tool - Antenna Data Worksheet(s) For both antenna types, antenna parameters like Tx/Rx gain, Tx insertion loss, Noise temperature for LNA and antenna at elevation angles 0-90° have to be inserted , refer to figure 3-12. The antenna name for each data set has to be unique.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool 3.5.3 Stations Worksheet Calculation Name) Figure 3-14 A) B) C) Link Budget Tool - Station Worksheet The station worksheet allows the storage of up to 23 network data. Use pre-defined Network Data To use pre-defined network data for the actual link budget calculation select the appropiate name by the pull-down menu ’Select Calculation here’.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Step (3) Figure 3-15 For each network up to 20 earth station parameter sets may be defined: - “Location”: Each earth station is identified by a unique location name. The first column is reserved for one master station, because the home channel of this station is fixed to carrier 1.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool off of solid state power amplifiers (SSPAs) are given by the table table 3-4. Note that if the amplifier’s power class is not defined by the saturation level but the 1 dB compression point (like for ND Satcom RFT 5000 series), no output back-off is required for single carrier operation. Number of IDUs connected to one SSPA Output back-off 1 1.0 2 3 3 4.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool 3.5.4 Tx Amplifier Worksheet In the TxAmp sheet the available amplifier power classes for Ku- and C-Band can be defined. Note that power classes have to be defined in ascending order. Besides defining the power classes it is also possible to specify the maximum power class available for SSPA amplifier types for Ku- and C-Band (input field markde in figure 3-18).
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool 3.5.5 Summary Worksheet Input Figure 3-18 Link Budget Tool - Summary Worksheet Input The input section of the summary sheet allows the definition of the carrier parameters for all SkyWAN® carriers used in the network.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Step (5) figure 3-18. The link calculation is triggered by pressing Ctrl-e or using the button on the upper left corner of the Summary sheet. Output The main output section consists of 2 parts: Figure 3-19 Link Budget Tool - Summary Worksheet Uplink The first part calculates power requirements for all stations to a specific downlink which can be defined by the ’Selected Downlink Location’ input box.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool in the TxAmp sheet. At the end of the general output field the ’Commercial Aspects for SkyWAN’ output represents the power requirement on the satellite transponder caused by the downlink to a specific station. Results for operation with and without UPC are stated in terms of a power equivalent bandwidth and are compared to the carrier bandwidth of the station’s home channel.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Optional Link Filter for Complex Topologies Normally the link budget tool calculates either meshed networks or star networks with up to two hub stations. More complex topologies like hybrid or multi-hub star networks may be defined by the link filter matrix at the bottom of the summary sheet. Figure 3-22 Link Budget Tool - Summary Worksheet Complex Filter By default every cell in this link filter matrix has the value 1.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Figure 3-23 MRB-Dub Network Overview As an example a link budget calculation for a network with stations located in Europe and Africa (ULA1) and America (ULA2) is presented. The transponders used for this network are served by the hemispherical beams on the SES World Skies Satellite NSS-7 (cf. chapter 3.2 for footprint diagrams of that satellite).
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Hub Stations The master and backup master station must be defined with 2 demodulator boards with the home channels carrier 1 and 2: Figure 3-26 MRB DUB Network - Hub Stations UpLink Area 1 (ULA1) The slave stations of ULA1 use carrier 1 for the primary demodulator. Any ULA1 station which should be able to communicate directly with a station in ULA2 must have a second demodulator using carrier 2 as its home channel.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool UpLink Area 2 (ULA2) Finally the slave stations in ULA2 use carrier 2 for the primary reception channel. Any station which wants to communicate directly to other ULA2 stations must also have a second reception channel on carrier 4. In this example all the stations in America are equipped for this mesh communication within ULA2.
Outdoor Unit and Satellite Link Design SkyWAN® Link Budget Calculation Tool Link Calculations The following links will be calculated by the link budget tool: - - For the master stations links to all other stations will be calculated. For slave stations in ULA1 links to all other stations in ULA1 will be calculated. Additionally for slave stations with second reception channel on carrier 2 also links to all stations in ULA2 will be calculated.
Outdoor Unit and Satellite Link Design Link Budget Examples 3.6 Link Budget Examples The following examples should present some typical link budget calculation scenarios and typical optimization steps. 3.6.1 Scenario 1: Ku-Band 5 Stations Fully Meshed The first scenario is a fully meshed 5 station network located in a Ku-Band spot beam over Europe and North Africa. Possible amplifier types should be ND Satcom RFT 5000 Ku-Band with 8, 20 or 30 Watt.
Outdoor Unit and Satellite Link Design Link Budget Examples Satellite Transponder Data Figure 3-34 Scenario 1 - Ku-Band Transponder Data Antenna Data Figure 3-35 Scenario 1 - Ku-Band Antenna Data Optimizations The result of user traffic and TDMA calculation for this network was a total modem data rate requirement of 8625 kbps. Preliminary link calculation showed that a single carrier solution would lead to a very high power requirement for the earth stations.
Outdoor Unit and Satellite Link Design Link Budget Examples For the stations as a first try we use 2.4m antennas on every site. Then the station parameters are given by: Figure 3-36 Scenarion 1 - 2 Carrier Solution Stations Now we calculate the link budget under the constraint that the power requirement for every site should not exceed 30 W.
Outdoor Unit and Satellite Link Design Link Budget Examples Link Budget Calculation Result Analysis - - Modulation and coding of both carriers is limited by the earth station in Casablanca which is located in a weaker part of the satellite footprint. Any increase of modulation and coding on carrier 1 and carrier 2 would increase the power requirement in Casablanca beyond 30 W. The network is not using the full power of the satellite transponder.
Outdoor Unit and Satellite Link Design Link Budget Examples Therefore, the modulation and coding on this carrier can be increased, leading to the following carrier coding and bandwidth: Star Network Carrier 1 Carrier 2 Modulation 8PSK 8PSK FEC 2/3 2/3 Estimated Symbol Rate [ksps] 2713 2203 Table 3-8 Total bandwidth required ( carrier spacing = 1.2) [KHz] 5900 Scenario 2 - Carrier Coding and Bandwidth Star Network; 2.
Outdoor Unit and Satellite Link Design Link Budget Examples Using a 3.8m antenna for the Casablanca earth station we can achieve the following modulation and coding parameters: Star Network; 3.8 m Antenna Casablanca Carrier 1 Carrier 2 Modulation 8PSK 8PSK FEC 6/7 6/7 Estimated Symbol Rate [ksps] 2138 1736 Table 3-10 Total bandwidth required ( carrier spacing = 1.2) [KHz] 4649 Scenario 2 - Optimized Carrier Coding and Bandwidth Star Network; 3.
Outdoor Unit and Satellite Link Design Link Budget Examples 3.6.3 Scenario 3: Ku-Band 5 Stations Star Network with 3 Hubs Finally we consider a slightly different scenario by assuming that now the station in Rome should also operate as a hub station for the network. Therefore, the home channel for Rome is changed to carrier 1.
Data Networking Introduction 4 DATA NETWORKING A brief description of the data networking protocols supported on the SkyWAN® IDU was given in chapter 2.2. This introduction was necessary to understand the user data rate requirements needed as an input for the user traffic estimation. 4.1 Introduction In this chapter details of the SkyWAN® implementation of the Internet Protocol (IP) as well as the Frame Relay (FR) protocol will be presented. 4.
Data Networking SkyWAN® Internet Protocol Features The physical layer is represented - on the terrestrial side by standard Ethernet LAN ports and a EIA-232 serial port for the service; - for the satellite interface by the SkyWAN® IDU modulator and demodulators MF-TDMA functionality. Note, that the logical IP interfaces are not bound to a specific physical board: i.e. even if only interface Sat-UT1 (SatOne) is used, data on this interface may be received by the primary or the secondary demodulator.
Data Networking SkyWAN® Internet Protocol Features SkyWAN® IDU 7000 Series Interfaces The figure 4-1 below represents an overview of the IP protocol stack of the SkyWAN® IDU 7000 series.
Data Networking SkyWAN® Internet Protocol Features SkyWAN® IDU 1070 Interfaces Figure 4-2 SkyWAN® IP Protocol Stack IDU 1070 Interface Number Port Number Interface Name User or Management Plane 5 1 LAN1 User Traffic 5 2 LAN2 User Traffic 5 3 LAN2 User Traffic 5 4 LAN4 Management 9 Sat-UT1; SatOne User & Management 10 Sat-UT2, SatTwo User & Management 11 Sat-UT3, SatThree User & Management 12 Sat-UT4, SatFour User & Management 13 Sat-MT Management dynamic Service Port
Data Networking SkyWAN® 4.2.2 Internet Protocol Features Basic IP Network Topologies The basic IP network topology of a fully meshed SkyWAN® network is displayed in figure 4-3. Figure 4-3 SkyWAN® Meshed IP Data and Management Network Each SkyWAN® IDU is connected via its Ethernet interface(s) to a local LAN IP network. On the satellite side each station is connected via its Sat-UTx interface(s) to a Core IP network.
Data Networking SkyWAN® Internet Protocol Features Figure 4-4 SkyWAN® Hybrid IP Data and Management Network For simplicity the station’s LAN networks have been removed from the diagram, only the IP over satellite networks are displayed. Like in the previous example, all the meshed stations are connected via their Sat-UT1 (SatOne) interfaces to a common meshed core IP subnetwork. Additionally there are two star subnetworks to which the hub stations are connected via their SatUT2 (SatTwo) interfaces.
Data Networking SkyWAN® - Internet Protocol Features Up to 600 static routes can be configured per station. Redistribution of static routes over the network (by means of OSPF) is possible. Static routes have precedence over dynamic OSPF routes. Static Routing in a Star Network IP connectivity between two star terminals in a star network may be enabled by defining static routes via the hub station.
Data Networking SkyWAN® Internet Protocol Features 4.2.4 Dynamic Routing with OSPF Besides static IP routing the SkyWAN® IDU supports the dynamic routing protocol ’Open Shortest Path First’ (OSPF) Version 2, as specified in RFC 2328. In general dynamic routing messages create a higher protocol overhead. But if the routing topology is static, OSPF messages do not create a high load on the network. As advantage of OSPF, changes in the topology (e.g.
Data Networking SkyWAN® 4.2.5 Internet Protocol Features Load Balancing for IP Unicast Traffic The dynamic load balancing feature helps to equalize the utilization of multiple frequency channels of a SkyWAN® network. Note that this feature is available for IP unicast only, dynamic load balancing for IP multicast or frame relay services is not supported.
Data Networking SkyWAN® Internet Protocol Features 4.2.6 Equalizing Path Costs for OSPF Networks In OSPF routing networks each router interface has an assigned cost metric value. The shortest path first algorithm determines the optimal path to any reachable destination by minimizing the summary cost metric. In the sample network displayed in figure 4-6 the destination network is reachable from IDU 1-3 via either IDU 4 or IDU 5.
Data Networking SkyWAN® 4.2.7 Internet Protocol Features IP Multicast Forwarding Beside unicast traffic the SkyWAN® IDU supports IP multicast services, i.e. traffic flows going to a group of recipients. The IP address range from 224.0.0.0 to 239.255.255.255 is reserved for IP multicast services. IP multicast services packet forwarding may be enabled on a SkyWAN® IDU by configuration: - the range from 224.0.0.0 to 224.0.0.
Data Networking SkyWAN® Internet Protocol Features allowed on these channels. For each entry in the multicast forwarding table which defines a multicast flow which should be received on the secondary demodulator in FMCA mode, the reception channel and a priority must be defined. If a host connected to the IDU’s LAN wants to receive a specific multicast stream, it sends an IGMP ’join’ request to the IDU.
Data Networking SkyWAN® Internet Protocol Features The following figure 4-7 presents an overview over all available forwarding behaviors and their mapping to the IP transmit queues. Figure 4-7 Mapping of Forwarding Behaviours to Transmit Queues Generally three traffic types can be distinguished: - IP Real time traffic: Forwarding behaviors Platinum and Platinum Dynamic define IP real time traffic flows which are mapped to the transmit queues IP Real Time 1 and 2.
Data Networking SkyWAN® Internet Protocol Features Gold-TCP-A, Gold, Silver, Bronze, Default All of these forwarding behaviors are mapped to the same transmit queue, i.e. they have the same transmit priority. However, packets belonging to a specific forwarding behaviors will only be accepted in the queue if its filling level is below a forwarding behavior dependent threshold, otherwise packets will be discarded (refer to table 4-3).
Data Networking SkyWAN® Internet Protocol Features Platinum Dynamic The Platinum Dynamic forwarding aggregate defines a ’on demand’ real time traffic flow. Capacity allocation is not done permanently but only if packets matching the aggregate’s definition are received on the Ethernet port. If the traffic flow stops for more than a configurable timeout period, the capacity is automatically released by the station.
Data Networking SkyWAN® Internet Protocol Features 4.2.9 Robust Header Compression For IP flows mapped to a Platinum Dynamic aggregate the SkyWAN® IDU may perform Robust Header Compression (RoHC) according to the RFC 3095. SkyWAN® applies unidirectional mode without feedback. Especially for VoIP connections header compression may save a substantial part of the bandwidth. Up to 128 flows can be compressed and decompressed at every station.
Data Networking SkyWAN® Internet Protocol Features The following figure 4-8 gives an overview of the necessary steps for header compression. Figure 4-8 RoHC Feature Overview If the compressor station detects that the IP flow mapped to a Platinum Dynamic aggregate can be compressed it will prepend the IP packet for the next 2 packets with a RoHC header.
Data Networking SkyWAN® Internet Protocol Features errors are more common on satellite links compared to terrestrial fibre optic links, this feature can reduce TCP throughput even further. To overcome these protocol drawbacks the SkyWAN® IDU supports a TCP acceleration functionality which is characterized by two main features: - Large window size (600 kByte); Selective Acknowledgements instead of cumulative acknowledgements.
Data Networking SkyWAN® 4.3 Frame Relay Networking Features SkyWAN® Frame Relay Networking Features On the serial user ports of the UIM board SkyWAN® IDU supports Frame Relay networking. The IDU acts as a Frame Relay switch, providing a User-to-Network (UNI) or Network-to-Network (NNI) service on these interfaces. Besides standard FR services according to the Frame Relay Forum UNI and NNI standards, SkyWAN® additionally supports the following features: - FR multicast connections.
Data Networking SkyWAN® Frame Relay Networking Features 4.3.2 Basic Frame Relay Services Basic Frame Relay is supported according to the Frame Relay Forum standards FRF 1.2 (UNI) and FRF 2.2 (NNI). Frame Relay Connectivity is based on the configuration of Permanent Virtual Circuits (PVC) which logically link serial data ports of SkyWAN® IDUs across the satellite network. Up to 300 PVCs can be defined on each serial port.
Data Networking SkyWAN® 4.3.3 Frame Relay Networking Features FR Communication Services and Quality of Service SkyWAN® networks supports 3 different generic Frame Relay communication services: - Realtime - Realtime Dynamic - Non-Realtime Besides these generic services there is also a special communication service SkyWAN® FAD if the device type connected to the IDU serial port is a SkyWAN® FAD.
Data Networking SkyWAN® Frame Relay Networking Features For FR Realtime Dynamic services - allocation will happen when the first user packet is received on the PVC. If no user packets are received for a configured timeout period, the capacity will be automatically released. If the necessary streaming capacity cannot be allocated due to carrier congestion, the Realtime PVC will be declared inactive, user traffic will then be discarded at ingress.
Data Networking SkyWAN® - Frame Relay Networking Features Committed Burst Size (Bc) Excess Burst Size (Be) If traffic shaping is enabled on a serial port, the received data volume within a measurement period Tc = Bc/CIR is monitored on each PVC. Received packets will be - accepted for forwarding to satellite if the received data volume for a measurement period is < Bc. - accepted but “tagged” if the received data volume is between Bc and (Bc + Be).
Page intentionally left blank 130 Network Design and Engineering Guide 2010-10-26
Summary and Design Implementation 5 SUMMARY AND DESIGN IMPLEMENTATION In chapter 2 the task has been discussed, how to design SkyWAN carriers to be optimally sized to fulfill customer traffic requirements. The major result of this calculation are the modem data rates for the individual SkyWAN carriers (which are used as input for the link budget calculation), to determine the optimal carrier modulation and coding and the required outdoor unit equipment. This task has been described in chapter 3.
Summary and Design Implementation fined if required. - Frame Relay Networking: - Port definition: Type and service of the required application has to be defined on the IDU serial port. - Local management interface (LMI) has to be defined according to the requirement of the connected Frame Relay device. - Permanent virtual circuits: PVCs have to be defined with a DLCI numbering scheme which may have to be adjusted to the customer’s PVC topology.
Appendix A - What’s new in this manual 6 APPENDIX A - WHAT’S NEW IN THIS MANUAL The following table highlights the changes in this manual release. Please refer to the SkyWAN® System Description for more information about new features in this release. Number Item Description 1 TDMA calculation New TDMA Calculator introduced.
Page intentionally left blank 134 Network Design and Engineering Guide 2010-10-26
Appendix B - Abbreviations 7 APPENDIX B - ABBREVIATIONS Abbreviation Meaning AFC Automatic Frequency Control ARP Address Resolution Protocol ASBR Autonomous System Boundary Router BDR Backup Designated Router BEC Backward Error Correction BER Bit Error Rate BERT Bit Error Rate Test CCR Convolutional Code Rate C/N Signal to Noise Ration CRC Cyclic Redundancy Check CW Continuous Wave DC Direct Current DCE Data Communication Equipment DIAG Diagnostic DL Downlink DLCI Data Li
Appendix B - Abbreviations Abbreviation Meaning FA Forwarding Aggregate FAD Frame Relay Access Device FB Forwarding Behavior FEC Forward Error Correction FMCA Flexible Multicast Channel Assignment FPG Frame Plan Generator FPS Front Power Supply FR Frame Relay FAD SkyWAN® Frame Relay Access Device. FRAD generic Frame Relay Access Devcice.
Appendix B - Abbreviations Abbreviation Meaning LED Light Emitting Diode LNA Low Noise Amplifier M&C Monitoring & Control MAC Media Access Control MAPNet Management Access Point for Network Management MAPNode Management Access Point for Node Management MF Multi-Frequency MF-TDMA Multi Frequency - Time Division Multiple Access MIB Management Information Base MOD Modulator MRB Multiple Reference Burst MRB-DUB Multiple Reference Burst - Dual Uplink Beam NFB-DUB No direct Feedback fo
Appendix B - Abbreviations Abbreviation Meaning QPSK Quadrature Phase-Shift Keying RCU Redundancy Control Unit RDR Regular Data Reception RF Radio Frequency RFC Request for Comment RFR Radio Frequency Receiver RFT Radio Frequency Transmitter RIP Routing Information Protocol RoHC Robust Header Compression RT Real-Time RTD Round Trip Delay RTP Real-Time Transport Protocol RTT Round Trip Time Rx Receive SAS Satellite Access Subsystem Sat-MT Satellite Port - Management Traffic
Appendix B - Abbreviations Abbreviation Meaning TCP Transmission Control Protocol TCP-A TCP Accelerator TDMA Time Division Multiple Access TPC Transmit Power Control TOS Type of Service TTL Time to Live Tx Transmit TWTA Travelling Wave Tube Amplifier UDP User Datagram Protocol UFC Uplink Frequency Control UIM User Interface Module UL Uplink ULA Uplink Area VoFR Voice over Frame Relay VoIP Voice over IP V2oIP Voice and Video over IP VSAT Very Small Aperture Terminal WAN
Page intentionally left blank 140 Network Design and Engineering Guide 2010-10-26
Appendix C - Glossary 8 APPENDIX C - GLOSSARY Term Definition Antenna For satellite communication over geosynchronous satellites parabolic reflector antennas are used. Backup Master A slave station that is ready in terms of hardware, software and configuration to take over the role of a master station. See also Master Station. Bandwidth A range of frequencies within a spectrum, expressed in Hertz. Also used for the data transfer rate or throughput, expressed in bits per second.
Appendix C - Glossary Term Definition Downlink Transmission of a signal from the satellite to the earth station. Digital Video Broadcasting_Satellite _Second Generation (DVB S2) Enhanced version of the DVB S satellite broadband transmission standard with forward error correction and modulation specifications.
Appendix C - Glossary Term Definition Intermediate Frequency (IF) From radio frequency (RF) down converted signal frequency used on the link between IDU and ODU. In a SkyWAN® network L-Band is used as intermediate frequency. Interface Set of definitions to describe the communication boundary between two systems or entities (seen as black boxes). Used in an overall context if you speak about logical (software) and physical (hardware) definition. See also Port. Ka Band Frequency band with uplink 26.
Appendix C - Glossary Term Definition Modem A piece of network equipment containing a modulator and demodulator for receiving or transmitting satellite signals. See SkyWAN® IDU. Modulation The encoding of a carrier wave by amplitude or frequency or phase. Multicast Multicast is a subset of broadcast whereby the signal can be sent to many sites within a defined group, but not necessarily to all sites in that group. Multicast Aggregate Group of multicast-microflows logically grouped together.
Appendix C - Glossary Term Definition Port 1. is normally used for the physical aspect of the systems boundary or 2. is defined as (logical application) port : i.e. port 21 for FTP. See also Interface. Propagation Delay The time it takes for a signal to go from the sending station through the satellite to the receiving station. This propagation delay for a single hop satellite connection is very close to 240 ms. See also Processing Delay and Latency.
Appendix C - Glossary Term Definition SkyNMS Network Management PC A PC on which the SkyNMS software is installed and running. The PC is locally connected to a SkyWAN® IDU over the Ethernet port. SkyWAN® Channel occupies frequency bandwidth on a satellite transponder for a SkyWAN® network; is configurable by SkyNMS. SkyWAN® Station Ground equipment that transmits and receives electromagnetic waves in a SkyWAN® network.
Appendix D - Install TDMA Calculator Standalone Tool Hardware Requirements 9 APPENDIX D - INSTALL TDMA CALCULATOR STANDALONE TOOL Beside the TDMA Calculation tool, integrated in the Network Configurator of SkyNMS, a standalone tool is available. In the following chapters hard- and software requirements as well as installation description is provided. Differences in the behaviour and handling of the two tool versions can be found in chapter 2.6 of this manual.
Appendix D - Install TDMA Calculator Standalone Tool Install TDMA Calculator Standalone Tool 9.3 Install TDMA Calculator Standalone Tool You need administrator rights for the installation of the SkyWAN® TDMA Calculator release 3.11. Write access to the installation directory is necessary. 1. Extract the zip file from CD and copy all files to a temporary directory. 2. Read the ‘readmefirst.
www.ndsatcom.
