TS 102 188-4 V112 (2004-07) Technical Specification Satellite Earth Stations and Systems (SES); Regenerative Satellite Mesh - A (RSM-A) air interface; Physical layer specification; Part 4: Modulation
2 TS 102 188-4 V112 (2004-07) Reference RTS/SES-00206-4 Keywords air interface, broadband, IP, multimedia, satellite 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloaded from: http://wwwetsiorg The present document may be made available in more than one electronic version or in print In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF) In case of dispute, the reference shall be the printing on printers of the PDF version kept on a specific network drive within Secretariat Users of the present document should be aware that the document may be subject to revision or change of status Information on the current status of this and other documents is available at http://portaletsiorg/tb/status/statusasp If you find errors in the present document, send your comment to: editor@etsiorg Copyright Notification No part may be reproduced except as authorized by written permission The copyright and the foregoing restriction extend to reproduction in all media European Telecommunications Standards Institute 2004 All rights reserved DECT TM, PLUGTESTS TM and UMTS TM are Trade Marks of registered for the benefit of its Members TIPHON TM and the TIPHON logo are Trade Marks currently being registered by for the benefit of its Members 3GPP TM is a Trade Mark of registered for the benefit of its Members and of the 3GPP Organizational Partners
3 TS 102 188-4 V112 (2004-07) Contents Intellectual Property Rights4 Foreword4 1 Scope 5 2 References 5 3 Definitions and abbreviations5 31 Definitions5 32 Abbreviations 5 4 General 6 5 Uplink6 51 Symbol rates and periods 7 52 Signalling constellation 7 53 Pulse shaping8 6 Downlink8 61 Symbol rates and periods 8 62 Signalling constellation 9 63 Pulse shaping10 631 PTP slots 10 632 Shaped-broadcast and idle slots10 Annex A (informative): Bibliography11 History 12
4 TS 102 188-4 V112 (2004-07) Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to The information pertaining to these essential IPRs, if any, is publicly available for members and non-members, and can be found in SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to in respect of standards", which is available from the Secretariat Latest updates are available on the Web server (http://webappetsiorg/ipr/homeasp) Pursuant to the IPR Policy, no investigation, including IPR searches, has been carried out by No guarantee can be given as to the existence of other IPRs not referenced in SR 000 314 (or the updates on the Web server) which are, or may be, or may become, essential to the present document Foreword This Technical Specification (TS) has been produced by Technical Committee Satellite Earth Stations and Systems (SES) The present document is part 4 of a multi-part deliverable covering the BSM Regenerative Satellite Mesh - A (RSM-A) air interface; Physical layer specification, as identified below: Part 1: Part 2: Part 3: Part 4: Part 5: Part 6: Part 7: "General description"; "Frame structure"; "Channel coding"; "Modulation"; "Radio transmission and reception"; "Radio link control"; "Synchronization"
5 TS 102 188-4 V112 (2004-07) 1 Scope The present document defines the modulation used within the SES BSM Regenerative Satellite Mesh - A (RSM-A) air interface family It includes the various modulation formats that are required for different physical channel types It also defines the concept of the transmission burst and the mapping of modulated symbols to the burst, and describes the required transmit filtering in general terms 2 References Void 3 Definitions and abbreviations 31 Definitions For the purposes of the present document, the following terms and definitions apply: Network Operations Control Centre (NOCC): centre that controls the access of the satellite terminal to an IP network and also provides element management functions and control of the address resolution and resource management functionality satellite payload: part of the satellite that provides air interface functions NOTE: The satellite payload operates as a packet switch that provides direct unicast and multicast communication between STs at the link layer Satellite Terminal (ST): terminal installed in the user premises terrestrial host: entity on which application level programs are running NOTE: It may be connected directly to the Satellite Terminal or through one or more networks 32 Abbreviations For the purposes of the present document, the following abbreviations apply: IP kbps Mbps NOCC NRZ OQPSK PSK PTP QPSK RSM ST Internet Protocol kilo bits per second (thousands of bits per second) Mega bits per second (millions of bits per second) Network Operations Control Centre Non Return to Zero Offset Quaternary Phase Shift Keying Phase Shift Keying Point-To-Point Quaternary Phase Shift Keying Regenerative Satellite Mesh Satellite Terminal
6 TS 102 188-4 V112 (2004-07) 4 General The functions of the physical layer are different for the uplink and downlink The major functions are illustrated in figure 4 Scrambling Scrambling Assemble packets into code blocks Assemble packets into code blocks Part 3: Channel coding Outer coding (Reed-Solomon) Outer coding (Reed-Solomon) No interleaving Block interleaving Part 2: Frame structure Inner coding (hamming) Uplink burst building Inner coding (convolutional) Downlink burst building Part 6: Radio link control Part 4: Modulation Uplink modulation (OQPSK) Downlink modulation (QPSK) Part 5: Radio transmission and reception ST transmitter n ST receiver t Part 7: Synchronization Timing and frequency control UPLINK DOWNLINK Figure 4: Physical layer functions The present document describes the modulation functions - this group of functions is highlighted in figure 4 The uplink modulation requirements are described in clause 5, and the downlink modulation requirements are described in clause 6 5 Uplink The uplink shall use Offset Quaternary Phase Shift Keying (OQPSK) modulation with square root raised cosine pulse shaping Encoded Bits Bits to Symbols I Q Pulse Shaping Z -1 I' Q' Modulator OQPSK Output Figure 5: Uplink modulator block diagram
7 TS 102 188-4 V112 (2004-07) 51 Symbol rates and periods The OQPSK symbol rates and corresponding symbol durations are as defined in table 51 Table 51: Symbol rates and periods Carrier mode Symbol rate, symbol/s Symbol duration, ns 128 kbps (see note) 520 5/6 10 3 1 920 512 kbps 520 5/6 10 3 1 920 2 Mbps 2 1/12 10 6 480 16 Mbps 16 ⅔ 10 6 60 NOTE: Each symbol is repeated four times The symbol rate is defined as: where B = 1,25 and N is defined below: 6 62,5 10 Symbol rate = N B N = 96 24 3 for the128 Kbps and 512 Kbps carrier modes for the 2 Mbps carrier mode for the16 Mbps carrier mode The symbol duration is the reciprocal of the symbol rate 52 Signalling constellation Each uplink symbol conveys two binary units of information, one on each of the I and Q arms In offset QPSK, the I arm data leads the Q arm data by one-half symbol The ST I-Q constellation plane is defined as a right-hand coordinate plane as shown in figure 521 On the I-Q constellation plane, a binary 0 value bit is defined as a positive (logical high), and a binary value 1 bit is defined as a negative (logical low) (1,0) Q 1 (I,Q) (0,0) I -1 1 (1,1) -1 (0,1) Figure 521: Uplink modulation constellation convention
8 TS 102 188-4 V112 (2004-07) The ST uplink modulator phasing convention is shown in figure 522 cos(ωt) I' Sum OQPSK Output Q' -sin(ωt) Figure 522: Uplink modulator phasing convention 53 Pulse shaping Each data bit to be modulated via the I and Q data arms is shaped by the following ideal time domain (impulse response) function: 4 h( t) = s β cos π [( 1+ β ) π s t] + (1/(4 β s t))sin[ ( 1 β ) π s t] 2 1 ( 4 β s t) where β = 0, 4 is the roll-off factor, t is the time, and s is the symbol rate ( ) 6 Downlink The downlink modulation for the PTP mode shall be Quaternary Phase Shift Keying (QPSK) with square root raised cosine pulse shaping The downlink modulation for the CONUS broadcast shall be NRZ QPSK 61 Symbol rates and periods The downlink operates at one of three possible transmission rates the ⅓-rate, the ¼-rate, and full-rate modes The QPSK symbol rates and corresponding symbol durations are as defined in table 61 Table 61: Symbol rates and periods Carrier mode Symbol rate, symbol/s Symbol duration, ns ¼-rate 100 10 6 10 ⅓-rate 133 ⅓ 10 6 7,5 Full rate 400 10 6 2,5
9 TS 102 188-4 V112 (2004-07) 62 Signalling constellation Each downlink symbol conveys two coded binary units of information, one on each of the I and Q arms The downlink I-Q constellation plane is defined as a right-hand coordinate plane as shown in figure 621 On the I-Q constellation plane, a binary 0 value bit (coded bit) is defined as a positive (logical high), and a binary value 1 bit is defined as a negative (logical low) (1,0) Q 1 (I,Q) (0,0) I -1 1 (1,1) -1 (0,1) Figure 621: Downlink modulation constellation convention The downlink modulator phasing convention is shown in figure 622 cos(ωt) I' Sum QPSK Output Q' -sin(ωt) Figure 622: Downlink modulator phasing convention
10 TS 102 188-4 V112 (2004-07) 63 Pulse shaping 631 PTP slots Each PTP slot data bit to be modulated via the I and Q data arms is shaped by the following ideal time domain (impulse response) function: h( t) 4 s β cos π [( 1 + β ) π s t] + (1/(4 β s t))sin[ ( 1 β ) π s t] 1 ( 4 β s t) = 2 ( ) where β = 0, 25 is the roll-off factor, t is the time, and s is the symbol rate For PTP mode, s = 400 Mbps A block diagram of the PTP pulse shaping is shown in figure 631 400 Msps 400 Msps Encoded Bits Bits to Symbols I Q Full Rate Pulse Shaping I' Q' Modulator QPSK Output Figure 631: PTP PSK symbol shaping 632 Shaped-broadcast and idle slots Each symbol is repeated three times (or four times in the case of the ¼-rate) as illustrated in figure 632, before passing the data through the pulse-shaping filter that is used for the full-rate PTP slots as described in clause 631 133 1/3 or 100 Msps 400 Msps 400 Msps Encoded Bits Bits to Symbols Repeat Symbol I Q Full Rate Pulse Shaping I' Q' Modulator QPSK Output Figure 632: Shaped-broadcast and idle PSK symbol shaping
11 TS 102 188-4 V112 (2004-07) Annex A (informative): Bibliography TR 101 984: "Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia; Services and Architectures" TS 102 188-1: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface; Physical Layer specification; Part 1: General description" TS 102 188-2: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface; Physical Layer specification; Part 2: Frame structure" TS 102 188-3: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface; Physical Layer specification; Part 3: Channel coding" TS 102 188-5: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface; Physical Layer specification; Part 5: Radio transmission and reception" TS 102 188-6: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface; Physical Layer specification; Part 6: Radio link control" TS 102 188-7: "Satellite Earth Stations and Systems (SES); RSM-A Air Interface Physical Layer specification; Part 7: Synchronization"
12 TS 102 188-4 V112 (2004-07) History Document history V111 March 2004 Publication V112 July 2004 Publication