`Int. J. Satell. Commun. Network. 2016; 34:351–360
`Published online 14 September 2015 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/sat.1135
`
`New DVB-S2X constellations for improved performance on the
`satellite channel
`
`Mustafa Eroz1,*,†, Lin-Nan Lee1, Nabil Loghin2, Ulrik De Bie3, Frederik Simoens3 and
`Daniel Delaruelle3
`
`1Hughes Network Systems, Germantown, MD, USA
`2Sony, Stuttgart, Germany
`3Newtec, Sint-Niklaas, Belgium
`
`SUMMARY
`
`Digital Video Broadcasting via satellite second generation has experienced worldwide adoption because of its rev-
`olutionary and yet practical physical layer technology and its flexibility. Recently, the standard has been updated
`with several new features without changing its fundamental structure. This paper provides a high-level discussion
`on several of the most important additions to the new standard with particular emphasis on some of the new signal
`constellations. Copyright © 2015 John Wiley & Sons, Ltd.
`
`Received 17 April 2015; Revised 12 June 2015; Accepted 27 July 2015
`
`KEY WORDS: DVB-S2X; higher order constellation; constrained capacity; phase noise; physical layer header;
`LDPC
`
`1. INTRODUCTION
`
`Digital Video Broadcasting via satellite (DVB-S) was initially conceived for Direct-to-Home (DTH)
`applications. The first generation DVB-S standard was based on quadrature phase shift keying modu-
`lation and convolutional code concatenated with Reed Solomon code. In 2003, DVB introduced a
`novel family of low-density parity check (LDPC) codes, which are not only within a dB of the theo-
`retical Shannon limit but also possess intrinsic structure that enables high-speed reception in an
`efficient way leading to practical implementation. This set of LDPC codes along with a set of ampli-
`tude and phase-shift keying (APSK)-based modulation forms the basis of DVB-S second generation
`(DVB-S2) standard [1]. Because of its unprecedented performance and availability of inexpensive
`receiver implementation, it soon saw worldwide deployment by the very small aperture terminal net-
`work operators as well as the satellite TV broadcasters. Other terrestrial and cable standards followed
`the footsteps of S2 (DVB-S2) by adopting the same set of codes. After 10 years since its introduction,
`even though there was no new breakthrough in the forward error correction technology, a new activity
`started to improve DVB-S2 on a system level without fundamentally changing its original structure.
`Finalized in 2014, this evolution of DVB-S2 is called DVB-S2X, or DVB-S2, Part II [2].
`DVB-S2X introduced additional modulation/coding pairs (modcods) to improve the granularity of
`S2, modified physical layer signaling (PLS) to enable these modcods, and extended the signal-to-noise
`ratio (SNR) range towards very low SNR (VL-SNR) to support mobile applications and ultra small-
`aperture terminals, as well as towards very high SNR to support professional applications. Moreover,
`a new frame structure has been defined for VL-SNR data, which allows these frames to coexist with
`‘regular’ transmission without causing the regular frames additional overhead. Furthermore, sharper
`
`*Correspondence to: M. Eroz, Hughes Network Systems, Germantown, MD, USA.
`†E-mail: meroz@hns.com
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005
`LG Electronics, Inc. v. Constellation Designs, LLC
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`Page 1 of 10
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`IPR2023-00319
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`M. EROZ ET AL.
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`roll-off factors have been introduced to improve the system spectral efficiency in certain conditions,
`and five additional configurable scrambling sequences have been defined to suppress co-channel inter-
`ference. Besides these physical layer improvements, DVB-S2X also introduced channel bonding,
`allowing operators to merge the capacity of several transponders, which helps increase the statistical
`multiplexing gain. Compared with single transponder schemes, channel bonding is expected to offer
`significant improvement especially with the introduction of ultra-high definition TV that requires very
`high data rate.
`This paper focuses on the introduction of new constellations for S2X (DVB-S2X) to improve the
`signal modulation. While S2 considered APSK constellations with ring ratios optimized for the linear
`additive White Gaussian noise (AWGN) channel, S2X focused on a more realistic nonlinear channel
`model, which reflects the behavior of modern linearized travelling wave tube amplifiers. For certain
`operation modes, the satellite link can also be considered as an instance of the classical linear AWGN
`channel, for which case non-uniform constellations (NUCs) [3] have been introduced.
`In this paper, we first provide an overview of improvements provided by S2X. Some of the new
`constellation designs are then presented along with theoretical and practical justifications. An extended
`PLS code is described that supports all of the new modcods of DVB-S2X without any fundamental
`change to the legacy PLS code and its DVB-S2 modcod codewords.
`
`2. OVERVIEW OF IMPROVEMENTS INTRODUCED BY NEW DVB-S2X CONSTELLATIONS
`
`2.1. Very low signal-to-noise ratio
`
`Mobile terminals and/or terminals with small apertures typically suffer from poor signal-to-noise ra-
`tios. In order to protect these terminals in high rain fade regions, novel modcods have been introduced
`in DVB-S2X. These modcods are based on π/2–binary phase shift keying modulation and are protected
`by low-rate LDPC codes (as low as code rate 1/5). These low code rates are further supported by sym-
`bol repetition (which leads to spreading by the particular scrambling sequence selected) to further re-
`duce the required SNR [4].
`As a result, DVB-S2X provides modcods that can operate at Es/No levels as low as 10 dB. In or-
`der to accommodate these new modcods, the PLS mechanism had to be adjusted as well. The original
`DVB-S2 PLS header was designed to operate reliably at symbol-energy per noise levels of slightly
`lower than Es/No = 2.5 dB. A new frame structure with a more robust VL-SNR header has been in-
`troduced in DVB-S2X. This new header can be decoded up to Es/No = 10 dB. Considering the fact
`that mobile and VL-SNR terminals are likely to be only a small minority of the population in any given
`network, only VL-SNR modcods are equipped with this better protected header. In this manner, only
`the VL-SNR frames exhibit additional PLS overhead, whereby regular frames still benefit from the ef-
`ficiency of the low overhead as in DVB-S2 [4].
`
`2.2. High signal-to-noise ratio modulation schemes
`
`Professional satellite applications often use receive stations with large antennas (compared with DTH
`terminals). Moreover, thanks to adaptive coding and modulation and/or uplink power control, these
`services operate with little fading margins. For these scenarios, DVB-S2X introduced higher modula-
`tion orders up to 256APSK, as opposed to 32APSK of DVB-S2. This significantly increases the spec-
`tral efficiency for links with a high signal-to-noise ratio (Es/No = 16 dB and above).
`
`2.3. Finer modcod granularity
`
`The new DVB-S2X standard introduces a large number of new modcods, in order to reduce the SNR
`spacing between individual modcods. Especially, in the Es/No range from 5 to 12 dB, which is typi-
`cally used for the important DTH applications, modcod Es/No separations have been reduced from
`1.5 to less than 0.5 dB. This allows to better match the modcod to the available SNR and to maximize
`the spectral efficiency.
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 2 of 10
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`NEW DVB-S2X CONSTELLATIONS FOR IMPROVED PERFORMANCE
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`2.4. Lower rate modcods
`
`In addition to finer granularity modcods, DVB-S2X also extends the S2 code rates to lower rates for
`any given constellation. From a theoretical point of view, this leads to more efficient modcods, because
`for a fixed constellation, the constrained capacity diverges from unconstrained capacity as SNR in-
`creases. Therefore, for any given bandwidth efficiency, it is more desirable to employ higher-order
`constellations and lower code rates as long as carrier synchronization is not an issue. As an example,
`the lowest code rate for 16APSK in DVB-S2 is 2/3. As a result, for links with less available SNR, one
`would have to resort to 8PSK modcods. DVB-S2X, on the other hand, provides with an extensive
`choice of 16APSK low code rates such as 1/2, 8/15, 5/9, 26/45, 3/5, 28/45, and 23/36, providing in
`most cases a more attractive solution than 8PSK. For example, rate 2/3 8PSK of DVB-S2 requires
`about Es/No = 6.6 dB with a throughput of about 2.0 bits/symbol, whereas rate 8/15 16APSK of
`DVB-S2X requires about the same SNR with a throughput of about 2.13 bits/symbol. Therefore, for
`this particular example, DVB-S2X provides more than 6% throughput improvement. On the other
`hand, it should be mentioned that the above example assumes a linear channel, or a multi-carrier trans-
`mission with sufficiently high output backoff. For nonlinear channels, the relative performance advan-
`tage of 16APSK with respect to 8PSK would diminish because of AM/AM nonlinear distortion.
`
`2.5. Linear and nonlinear modulation schemes
`
`DVB-S2X introduces two categories of new modcods. The bulk of new modcods have been optimized
`for a nonlinear channel. A hard-limiter channel was used as a reference channel model to optimize the
`modulation parameters. Next to these so-called nonlinear modcods, the new standard also introduced a
`number of modcods optimized for a linear AWGN channel. Such a channel model is representative for
`scenarios whereby multiple carriers are placed on a transponder, and a large output backoff is
`employed. In addition to optimizing performance for the AWGN channel, some linear modcods, such
`as 2 + 4 + 2APSK, offer vastly improved synchronization performance compared with their nonlinear
`counterparts (8PSK).
`
`3.1. Design methodologies
`
`3. NEW CONSTELLATIONS OF DVB-S2X
`
`Digital Video Broadcasting-S second generation has often been cited as the forefront of communica-
`tion systems, which can approach the ultimate limits for reliable data transfer, set by the famous Shan-
`non limit [4]. For low constellation sizes, like quadrature phase shift keying, the S2 modcods have
`approached the theoretical limits by less than 1 dB, which can be contributed mostly to the powerful
`deployed LDPC codes. Further improving the forward error correcting codes was thus a difficult task,
`which resulted in only minor potential gains over the last 10 years. For the extension of DVB-S2, it was
`only natural to improve modcod performance by tackling the second ingredient: the constellations [5].
`For linear modcods of DVB-S2X, NUCs [3] have been optimized, which aim at maximizing the
`Bit-Interleaved Coded Modulation (BICM) capacity [6] of the AWGN channel, including mapper
`and optimum demapper. In particular, certain parameters of the constellations are optimized using a
`constrained nonlinear optimization algorithm [7] for SNR values in the proximity of LDPC waterfall.
`Thereby, these constellations allow for maximized reliability values at the input to the LDPC decoder,
`reducing decoding error probabilities.
`For example, for a 16-ary constellation, all 16 complex constellation points have been used as var-
`iables for a nonlinear optimization problem (maximizing capacity), with the constraint that the average
`power of all points needs to be normalized, for example, to 1. As a remarkable outcome, these NUCs
`usually exhibit amplitude and phase-shift keying-like structures, allowing simple implementation, high
`resilience to phase noise and low peak-to-average power ratio values.
`As an example, a 16NUC has been optimized for LDPC code rate of 3/5. The design SNR for this
`NUC takes the waterfall of the bit error rate (BER) curve into account. The waterfall of an LDPC BER
`curve is the narrow SNR region, in which the curve dramatically drops by several orders of magnitude,
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 3 of 10
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`M. EROZ ET AL.
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`in this case at about 7 dB. Figure 1 depicts the constellation points of this NUC, where the bit labels are
`attached to the points and given in integer numbers (e.g., 7 denotes bit labels 0111). It should be noted
`that the constellation is not exactly an 8 + 8APSK constellation, but more precisely a 4 + 4 + 4 + 4APSK
`with minor differences in the ring radii.
`Figure 2 shows the BER and frame error rate (FER) for this new S2X constellation over the AWGN
`channel. Both modcods use the 64k LDPC code from S2 (even though the new S2X modcod introduced
`both a new constellation and a new LDPC code of rate 3/5). An outer Bose-Chaudhuri-Hocquenghem
`(BCH) code with t = 12 error correction capability is deployed, and no roll-off was applied. As can be
`seen, the new constellation allows reception at 0.35 dB lower SNR, which can be considered as an ex-
`traordinarily large shaping gain, considering the limited number of degrees of freedom. The potential
`shaping gain for 16-ary NUCs, when compared with uniform quadrature amplitude modulation constel-
`lations, as for example, deployed in terrestrial and cable standards, is in the order of only 0.1–0.2 dB [3].
`As another example, Figure 3 shows a new 64-ary constellation introduced by DVB-S2X. This con-
`stellation has a symbol arrangement of 8 + 16 + 20 + 20APSK. Figure 4 depicts a constrained capacity
`comparison of several 64-ary constellations where the S2X constellation achieves the highest capacity.
`It is also worth mentioning that this constellation achieves optimum or very close to optimum results
`on both linear and nonlinear channels as tested through extensive computer simulations.
`Figure 5 depicts the new 2 + 4 + 2APSK linear constellation. Figure 6 illustrates the improved syn-
`chronization properties of this new constellation compared with its well-known 8PSK counterpart.
`
`11
`
`2
`
`6
`
`3
`
`7
`
`9
`
`0
`
`4
`
`1
`
`5
`
`8
`
`12
`
`15
`
`13
`
`-1
`
`0
`Re{xl}
`
`1
`
`10
`
`1.5
`
`1
`
`0.5
`
`0
`
`Im{xl}
`
`-0.5
`
`14
`
`-1
`
`-1.5
`
`Figure 1. 16NUC for S2X for code rate of 3/5.
`
`100
`
`10-2
`
`10-4
`
`10-6
`
`BER (solid) , FER (dashed)
`
`10-8
`6.8
`
`6.9
`
`7
`
`R3/5, 16APSK (S2)
`R3/5, 16NUC (S2X)
`
`7.1
`Es/N0 [dB]
`
`7.2
`
`7.3
`
`7.4
`
`Figure 2. Performance of optimized non-uniform constellation (NUC) over additive White Gaussian noise channel
`compared with S2 constellation.
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 4 of 10
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`NEW DVB-S2X CONSTELLATIONS FOR IMPROVED PERFORMANCE
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`355
`
`Figure 3. 64-Ary constellation of DVB-S2X.
`
`Figure 4. Constrained capacity comparison of several 64-ary constellations.
`
`Consequently, the 2 + 4 + 2APSK constellation can often be operated with pilots switched off, resulting
`in 2.5% overhead reduction. This benefit comes on top of an SNR gain of 0.2dB for standard (non-it-
`erative) demapping and LDPC decoding.
`
`3.2. Phase noise resilience
`
`The DVB-S2X User Guidelines [8] detail the phase noise assumptions for the different satellite system
`components and for various service types, resulting in end-to-end phase noise masks denoted as P1
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 5 of 10
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`Figure 5. 2 + 4 + 2APSK constellation.
`
`Figure 6. 2 + 4 + 2APSK improved synchronization performance for non-data-aided carrier synchronization (when
`pilots not used).
`
`(first priority; legacy components) and P2 (second priority; year 2012 state-of-the-art system compo-
`nents). It was verified that constellations up to 64APSK operate under the P1 mask for the very small
` 5. At higher
`aperture terminal outbound channel at 10 MBd with degradation below 1.5dB @FER = 10
`outbound channel symbol rates, this degradation dwindles. The P2 mask on the other hand permits de-
`ployment of 256-ary constellations with very low degradation down to at least 1 MBd, thereby en-
`abling highly efficient professional services. Figure 7 illustrates the simulated phase noise resilience
`of a (nonlinear) 256-APSK constellation, assuming linear interpolation between estimated pilot phases.
`
`4. EXTENDED PLS CODE OF DVB-S2X
`
`In DVB-S2, a physical layer header is transmitted before each LDPC coded data to signal the receiver
`the modcod identity (5 bits), the length of the code (1 bit), and the presence/absence of pilots (1 bit).
`The seven bits are coded into 64-coded bits using a first order Reed–Muller code. For DVB-S2X, on
`the other hand, in order to signal the additional modcods, the standard extends the original DVB-S2
`PLS code in a backwards compatible way. DVB-S2X defines an additional eighth bit b0. For all
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 6 of 10
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`NEW DVB-S2X CONSTELLATIONS FOR IMPROVED PERFORMANCE
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`357
`
`Figure 7. Performance of modcod 256APSK-32/45 for P2 and P1 phase noise profiles.
`
`DVB-S2 modcods, this bit b0 is set to 0, and the PLS code remains the same as DVB-S2. For the newly
`introduced DVB-S2X modcods, this bit b0 is set to 1. For the case of b0 = 1, the length bit is used in the
`signaling of additional modcods. The reason of this change is that in DVB-S2X, the majority of the
`modcods are already of normal length. So listing the short modcods explicitly instead of allocating
`an entire bit field to signal the length is more economical. In order to keep the performance of non-
`coherent decoding of the PLS code almost similar to DVB-S2, the bit b0 is signaled using an updated
`(32, 7) generator matrix as shown in Figure 8. This generator matrix is identical to the (32, 6) generator
`matrix in DVB-S2 except the inclusion of a new first row. As a result, when b0 = 0, the resulting
`codeword is identical to the DVB-S2 PLS codeword. As in DVB-S2, the particular construction in Fig-
`ure 8 guarantees that each odd bit in the (64, 8) code is either always equal to the previous bit or is
`always opposite to the previous bit depending on the value of b7. This fact can be exploited in case
`differentially coherent detection is adopted in the receiver.
`It should be mentioned that the (32, 7) code does not maintain the bi-orthogonal property of the (32,
`6) code. The minimum distance between the code words is somewhat reduced. To preserve the error
`rate performance, the set of codewords corresponding to the DVB-S2 modcods are made orthogonal
`to the set of codewords corresponding to new DVB-S2X modcods in the modulation space.
`Similar to the DVB-S2, 64 symbol PLS code is π/2 BPSK modulated and transmitted after the 26
`symbol start of frame (SOF) field. When b0 = 0, the π/2 BPSK modulation regularly continues after
`the SOF field as for S2, while if b0 = 1, a phase jump of π/2 is introduced after the SOF field. As a re-
`sult, not only this one additional bit is encoded without changing the number of coded symbols in a
`backward compatible way but also the performance of the DVB-S2X PLS code only degrades slightly
`from that of the DVB-S2 PLS code. The coherent detection performance of DVB-S2X (64, 8) code is
`compared with that of S2 (64, 7) code in Figure 9. As shown by the simulation results, the performance
`penalty for sending one more data bit is about twice the error rate of the S2 case, because in the two-
`dimensional phase space, there are now two sets of codewords, orthogonal to each other due to the 90°
`phase shift, where the codewords in each set are mutually orthogonal.
`
`Figure 8. DVB-S2X physical layer signaling code (the symbol ⊗ stands for binary Exclusive or (EXOR)).
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 7 of 10
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`Figure 9. Performance comparison of S2 and S2X physical layer signaling codes with non-coherent detection.
`
`For non-coherent detection, however, the phase shift is no longer distinguishable, and the first row
`of the generator matrix is used to differentiate the set of codewords corresponding to S2 or S2X
`modcods. Performance comparison of the two PLS codes with non-coherent detection is also shown
`in Figure 9. Due to the fact that the two sets of codewords are actually orthogonal to each other in
` 6
`the modulated space, the performance loss of the S2X PLS code is still less than 0.3 dB at FER = 10
`from the non-coherent detection performance of the original DVB S2 PLS.
`
`5. CONCLUSION
`
`improvements on
`Digital Video Broadcasting-S second generation offers several additional
`DVB-S2 without modifying any aspect of the original standard and by keeping the underlying
`structure the same. New constellations with improved constrained capacity and better phase noise
`resiliency have been introduced. As a result, the updated standard covers 30 dB range of Es/No
`from 20 dB down to 10 dB, while maintaining a performance very close to Shannon capacity.
`Based on the successful history of DVB-S2, it can be expected for DVB-S2X to be also widely
`adopted for many years to come.
`
`REFERENCES
`
`1. “EN 302 307”, Digital video broadcasting (DVB); Second generation framing structure, channel coding and modulation
`systems for broadcasting, interactive services, news gathering and other broad-band satellite applications.
`2. “EN 302307-2”, Digital Video Broadcasting (DVB); Second generation framing structure, channel coding and modulation
`systems for broadcasting,
`interactive services, news gathering and other broadband satellite applications; Part
`II:
`S2-Extensions (S2-X).
`3. Zoellner J, Loghin N. “Optimization of high-order non-uniform QAM constellations,” Broadband Multimedia Systems and
`Broadcasting (BMSB), 2013 IEEE Int. Symp. on, June 2013.
`4. Lee L, Eroz M, Becker N. Modulation, coding, and synchronization for mobile and very small satellite terminals as part of the
`updated DVB-S2 standard. Int J Satell Commun, this issue.
`5. Forney GD, Gallager R, Lang G, Longstaff F, Qureshi S. Efficient modulation for band-limited channels. IEEE J Sel Area
`Comm 1984; SAC-2(5):632–647.
`6. Caire G, Taricco G, Biglieri E. Capacity of bit-interleaved channels. IEE Electron Lett 1996; 32(12):1060–1061.
`7. Byrd RH, Gilbert JC, Nocedal J. A trust region method based on interior point techniques for nonlinear programming. Math
`Program 2000; 89(1):149–185.
`8. “ETSI TR 102 376-2”, Digital video broadcasting (DVB); User guidelines for the second generation system for Broadcasting,
`Interactive Services, News Gathering and other broadband satellite applications – part 2: S2-extensions (DVB-S2X).
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 8 of 10
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`
`AUTHOR’S BIOGRAPHIES
`
`Mustafa Eroz received his PhD from the University of Maryland, College Park in 1996
`where he was an Institute for Systems Research fellow. Since then, he has been with the
`Advanced Development Group of Hughes Network Systems. His current research interests
`include error control coding, multiple access schemes, coding for multiple antennas, and
`iterative receiver techniques. He played a leading role in the design of a new class of LDPC
`codes adopted by DVB-S2 and DVB-S2X and, in the specification of the turbo code,
`adopted in IEEE 802.11n. He received numerous awards from Hughes.
`
`Lin-Nan Lee received his BS degree from National Taiwan University, his MS and PhD
`from the University of Norte Dame, all in Electrical Engineering. He is a Vice President
`of Engineering of Hughes leading its Advance Development Group. His research areas
`include data compression, channel coding, modulation, multiple access, and antenna signal
`processing. He actively participated in and made major contributions to DVB-S2 and
`DVB-S2X standardization activities. He also participated and contributed to wireless
`communications standards such as 3GPP, 3GPP2, and IEEE802.11.n, particularly in the
`area of forward error correction coding.
`
`Nabil Sven Loghin (born Muhammad)
`received his diploma degree in Electrical
`Engineering and PhD degree from the University of Stuttgart, Germany, in 2004 and
`2010, respectively. Since 2009, he has been with Sony, working on DTV standardization
`and localization algorithms. His research interests include channel coding,
`iterative
`decoding, QAM mapping optimization, and multiple-antenna communications.
`
`Ulrik De Bie entered the world of satellite telecommunication when he joined Newtec Cy,
`Belgium as a system engineer in 2001/2002. His research interests include DVB-RCS and
`DVB-RCS2 satellite scheduling and encapsulation in the return link, ACM scheduling and
`encapsulation in DVB-S/S2/S2X forward link, control plane functions in satellite internet
`access systems, and user plane performance improvement. He is an active participant in
`the specification and engineering of satellite telecommunication standards. He participates
`in DVB TM and the ad hoc working groups TM-S2 (Wideband, DVB-CID, DVB-S2X),
`TM-GBS (GSE, SI), and TM-RCS (RCS and RCS2). He received the Licentiaat
`Informatica degree from the Katholieke Universiteit Leuven, Belgium, in 1998.
`
`Frederik Simoens obtained a Masters degree in Electrical Engineering and a PhD degree in
`Digital Communications, both from the University of Ghent
`in 2003 and 2008,
`respectively. He also holds an MBA degree from Vlerick Business School. Since 2008,
`he has been working at Newtec, a satellite equipment manufacturer. His key areas of
`expertise include physical layer technologies and satellite communication modems and
`systems.
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
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`Constellation Exhibit 2005, Page 9 of 10
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`
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`360
`
`M. EROZ ET AL.
`
`Daniel Delaruelle has been active in satellite communications since 1985 and joined
`Newtec Cy, Belgium in 1988, where he took up equipment design, team lead, and staff
`scientist positions. His research interests include system synchronisation, waveform design,
`optimal resource scheduling, channel estimation, and distortion/interference countermea-
`sures. He made key contributions to widely deployed standard-based and proprietary
`satellite transmission technologies and served on the DVB ad hoc workgroups evolving
`the DVB-DSNG, DVB-RCS, DVB-S2, DVB-S2X, and DVB-CID specifications. He
`received his Masters degree in Electrical Engineering from the University of Ghent,
`Belgium, in 1984.
`
`Copyright © 2015 John Wiley & Sons, Ltd.
`
`Int. J. Satell. Commun. Network. 2016; 34:351–360
`DOI: 10.1002/sat
`
` 15420981, 2016, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/sat.1135 by Reprints Desk Inc, Wiley Online Library on [10/01/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License
`
`Constellation Exhibit 2005, Page 10 of 10
`
`