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Modern complex drilling systems contain communication nodes like sensors, actuators, and controllers, spread along the lower end of a drill string. Here, temperatures of more than 150 °C and pressure levels up to 200 MPa are present. These environmental conditions and mechanical shocks, are extremely challenging for the reliable use of electronic components. A powerline communication system is designed and evaluated to establish a robust communication channel with low amounts of wiring. This system can operate on highly distorted physical transmission channels by adding redundancy at the sender that can then be used to correct errors at the receiver. In order to synchronize the real-time clocks among different powerline stations, a new preamble extension approach that enables precise time synchronization between multiple bus nodes is added. After design and verification, this system was manufactured in XFAB 180 nm Silicon-On-Insulator (SOI) technology allowing operating temperatures of up to 175 °C. The die size is 5.25 mm × 5.25 mm and contains a complete HomePlug 1.0 communication stack with an environment for boot, interfacing, and debugging. Its data rate reaches 6.1 Mbit/s using the fastest transmission mode and the theoretical maximum of 0.55 Mbit/s in the robust OFDM (ROBO) mode, which is of particular interest for harsh environment applications. After verifying the fabricated die, a Printed Circuit Board (PCB) for climate chamber evaluation was designed and fitted. Measurements in this chamber carried out a maximum ambient temperature of 190 °C for communication with a minimum self-heating of the die of 20 °C measured at room temperature. In combination, this is 35 °C above the specification of the technology process. The timing synchronization evaluation showed a precision of 55.6 ns over the temperature range from -30 °C to 185 °C, which is as low as 1.5 clock cycles. Power measurements of up to 190 °C have shown an average power consumption increase of only 63μW/K below 150 °C and a maximum increase of 394μW/K above 150 °C. To the best of the authors’ knowledge, this is the first high-temperature evaluation of a powerline communication ASIC, which is particularly designed for a drilling system's harsh environment.

Broadband powerline communication systems using Orthogonal Frequency Division Multiplexing (OFDM) can utilize existing power lines to transmit data packets alongside power distribution. Recent standards focus towards high speed multi-media in-house streaming. With improvements towards robustness and throughput new standards increase the speed and reliability of in-house powerline systems. A very different approach is the use of powerline communication systems in a deep drilling environment where temperatures of more than 150°C and pressure levels up to 30 000 psi are present. Typical applications in this environment usually do not require more than several kbit/ys per node and are more reliant on a stable and continuous connection. Here, a powerline communication system can reduce the amount of wiring needed and increase communication robustness significantly. This work provides a harsh environment suitable, reliable and standard compliant communication ASIC that is manufactured in XFAB 180 nm Silicon-On-Insulator (SOI) technology allowing operating temperatures of up to 175°C. The die size is 5.25 mm x 5.25 mm and contains a complete Homeplug 1.0 communication stack with an environment for boot, interfacing and debugging. The data rate is as high as 6.1 Mbit/s using the fastest transmission mode and reaches the theoretical maximum of 0.55 Mbit/s in the robust OFDM (ROBO) mode which is of particular interest for harsh environment applications. To the best of the authors knowledge, this is the first OFDM-based powerline communication ASIC which is particularly designed for harsh environment.© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Vologesia rollingstones sp. nov. (Figs. 3, 4, 5 A–B, D, F) http://zoobank.org/urn:lsid:zoobank.org:act:2A9719F4-7629-41E9-9962-B0AAEF5EEDE9 2014 Vologesia sp., Saura & García p. 306, pl. 104, Figs. 3 a–c. Types. Holotype is MB.E.6224 (Fig. 3 A–C), paratype is MB.E.6225 (Fig. 3 D–F), contained in the collections of the Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung (Berlin, Germany). Locus typicus. Coastal section near the small village of Langre, northern Cantabria (Spain). Stratum typicum. Sponge Rhythmites (Scaphites hippocrepis III Zone, lower Campanian). Derivatio nominis. Named after British Rock’ n’ Roll band The Rolling Stones for the song “Gimme Shelter (1969) and all the rest. Material. 22 complete and three fragmentarily preserved specimens (MB.E.6224–6237 and MB.E.11452- 11462). Diagnosis. Small, flattened species of Vologesia with a teardrop-shaped outline. The apical disc is positioned anteriorly and tetrabasal, with a prominent madreporite. The periproct is inframarginal. The pentagonal peristome is laterally elongated. Perioral ambulacrals show flush, short phyllodes with an inner and outer series of pore pairs. Bourrelets are only weakly developed. Description. Vologesia rollingstones sp. nov. is a small species that does not exceed 25 mm in overall test length and is characterised by a flattened, ovoid test, with its widest point approximately in the posterior lower third of the test. The margins of the flattened oral surface are well rounded. The oral surface is more convex in small-sized specimens (> 13 mm). The posterior side projects into the inframarginal periproct, thus, the test is slightly teardrop shaped in dorsal view. The ambitus is positioned in the lower third of test height. The aboral surface is generally flattened. The position of the apical disc is variable, ranging between 32 and 42% of test length to the anterior margin; in general, it is closely situated to the anterior edge (35% of test length). The apical disc is tetrabasal, the madreporite being formed by a large genital plate 2, which occupies the centre of the apical disc, the remaining genital plates being reduced in size (Fig. 5 F). Adapically, the ambulacra are petaloid, having 46 pore pairs in the posterior petals and 41 in the anterior petals, respectively, at a test size of c. 19 mm and 34 in the posterior petals, 31 in the anterior petals, respectively, at a test length of c. 14 mm. Petals are relatively short, the anterior ones ranging between 17 and 26% of test length (average 22%) and posterior ones between 21 and 29% (average 26%). The shape of the petals varies from straight to slightly bowed. Petals bear conjugate anisopores. The peristome is small, laterally elongated and pentagonal in outline. The distance from the peristome to the anterior margin is 25–35% of test length (average 30%). The bourrelets are only weakly developed, which is why only an imperfect floscelle structure is developed. Short phyllodes, which are flush to the oral surface, are simple, being composed of an outer series with 7 pores and an inner series of 2 pores (see Fig. 5 D); the inner pores are carried by occluded plates; small buccal pores are present. The laterally elongated, oval periproct has an inframarginal position. The tuberculation is fine and dense, with tubercles decreasing in size in aboral direction. A narrow, pitted band without tubercles extends from the peristome to the periproct. Discussion. So far, the genus Vologesia comprised only three species; V. tataosi, V. rawdahensis and V. toucasi. From V. rawdahensis (for a detailed description, see Smith, 1995), V. rollingstones sp. nov. can be distinguished by its smaller size, a more rounded ambitus, a more anteriorly situated apical disc and shorter petals, while the peristome is further to the anterior margin (21–27% of test length in V. rawdahensis). In addition, a third inner series of pores in the phyllodes is partially developed in V. rawdahensis, while this is absent from V. rollingstones sp. nov.; the inner pores in the phyllodes of the latter are dispersed, in contrast to V. rawdahensis. Ali (1989) noted that V. rawdahensis was similar to V. tataosi and could only be distinguished from the latter by a more elongate and pointed posterior test with a smaller peristomal opening. Thus, V. rawdahensis and V. tataosi might turn out to be conspecific (see discussion in Smith, 1995). Other species that had previously been placed in Vologesia by Lambert and Thiéry (1909 –1925), including Conoclypus rhothomagensis d’Orbigny, 1855, Clypeolampas ovum de Grateloup, 1836, Clypeolampas conicus Arnaud, 1877, Clypeolampas gossaviensis Lambert, 1907, Clypeolampas helios Noetling, 1897 and Echinolampas acuta Des Moulins, 1837), are better assigned to Hungaresia or Clypeolampas (compare Smith, 1995). They can all be distinguished from V. rollingstones sp. nov. by their inflated tests, longer petals, more centrally positioned peristome and swollen bourrelets. The degree of bourrelet development cannot be identified in C. gossaviensis [treated by Smith (1995) as a nomen dubium] and C. conicus on the basis of their original descriptions.

Genus Vologesia Cotteau & Gauthier, 1895 Type species. Vologesia tataosi Cotteau & Gauthier, 1895, p. 66, by monotypy. Diagnosis. Apical disc tetrabasal with large madreporite, other genital plates reduced in size; peristome close to anterior margin, 20–35% of test length away from it; bourrelets only very weakly developed; phyllodes with 2–3 series of pores; peristome pentagonal and laterally elongated (modified from Smith, 1995, p. 190). Remarks. Vologesia, Hungaresia Szörényi, 1955 and Clypeolampas Pomel, 1869 are closely similar; according to Smith (1995), there are few stable characters to differentiate between these genera. For example, Clypeolampas and Hungaresia have subcentrally positioned peristomes, while in Vologesia it is in a more anterior position. Smith (1995) also indicated the peristome to be placed at 20–30% of test length from the anterior border as diagnostic feature in Vologesia. These values were based on V. toucasi (Lambert, 1911) and V. rawdahensis Ali, 1989. This range can now be extended to 20–35% on the basis of our description of Vologesia rollingstones sp. nov., illustrating the position of the peristome to be more variable than previously suggested by Smith (1995). The presence of bourrelets (i.e., swollen perioral interambulacral plates) appears to be a more reliable character for differentiating between Clypeolampas, Hungaresia and Vologesia; in the last-named genus bourrelets are missing. Furthermore, aboral pustular granules are present only in Clypeolampas (see Smith, 1995). Occurrence. Vologesia toucasi is known from the upper Santonian of Aude, southern France (Lambert, 1911) and the upper Santonian of south central Pyrenees, Lleida province, north-eastern Spain (Gallem, personal communication), V. tataosi from the “Senonian of Louristan, Iran (Cotteau & Gauthier, 1895) and V. rawdahensis from the mid-Maastrichtian of the United Arab Emirates/Oman border region (Ali, 1989).

Vologesia toucasi (Lambert, 1911) (Figs. 5 C, E, G, 7) 1911 Clypeolampas toucasi Lambert, p. 155, pl. 3, Figs. 1–3. 2014 Hungaresia toucasi (Lambert), Saura & García p. 306, pl. 104, Figs. 1 a–c. Type. Holotype, by monotypy, is the specimen illustrated by Lambert (1911, pl. 3, Figs. 1–3), in the Lambert Collection at the Muséum national d’Histoire naturelle, Paris ( MNHN.F.J01723) (not seen). It is from Sougraigne in the Corbières (Aude, France), having been collected from the “couches Hippurites... avec Actinocamax Grossouvrei. Lambert (1911) considered those strata to be of Campanian age. According to the revised stratigraphy by Christensen et al. (1993), these levels are of late Santonian age (Placenticeras polyopsis / Texanites gallicus Zone). Material. A single near-complete and four fragmentarily preserved specimens (MB.E.11463-11467) from the top of Bed 200, upper Santonian (Placenticeras polyopsis Zone), deposited in the Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung (Berlin, Germany). Diagnosis. Small species with a domed to conical test and a flattened oral surface. The tetrabasal apical disc, with a prominent madreporite, is in a central position. The pentagonal, laterally elongated peristome is positioned close to the anterior margin. The phyllodes are short and slightly sunken, with an inner and an outer series of pore pairs; bourrelets are weakly developed. Description. Vologesia toucasi is a small species with a maximum test length of c. 35 mm. The oval tests are domed to conical in profile, with its longest axis along the anterior-posterior direction in cross section. The ambitus is positioned close to the oral surface, in the lower quarter of test height. The apical disc is positioned at 47% of test length to the anterior margin. The apical disc is not completely preserved; it was presumably tetrabasal, with the madreporite formed by the large genital plate 2, occupying the centre of the apical disc, while other genital plates are much reduced in size (Fig. 5 G). Petaloid ambulacra are present adapically; pore counts are not available due to poor preservation. The straight petals are relatively short, not reaching below the upper third of test height. Conjugate anisopores can be recognised within the petals. The small peristome is laterally elongated and has a pentagonal outline. It is positioned anteriorly, with a distance to the anterior margin of 29% of test length (at a length of 29.8 mm). A weakly pronounced floscelle structure can be seen; the bourrelets are only weakly swollen, in combination with only slightly sunken phyllodes. The phyllodes are short, with an outer series of 10–11 pores, including small buccal pores, and an inner series of 3–4 pores (see Fig. 4 C). The oval periproct is inframarginal. The tubercules generally are small, largest on the oral surface and decreasing in size in aboral direction. A narrow, granular band without tubercles extends from the peristome to the periproct. Discussion. Our record of V. toucasi from the upper Santonian of Langre is in accordance with the stratigraphic position of the type series from the Corbières, southern France and extends the known geographic range of the species to Spain. Vologesia toucasi differs from V. rollingstones sp. nov. by its subconical to conical profile and in phyllode structure that generally reveals a floscelle on account of more pronounced bourrelets. This species has a more inflated and circular shape in comparison to V. rawdahensis and V. tataosi. In addition, the apical disc is more central. Lambert (1919) mentioned Vologesia acuta (Des Moulins, 1837) from the Santander region. This is better referred to Clypeolampas (see Smith, 1995) and differs to Vologesia by a more centrally positioned peristome and better-developed bourrelets., Published as part of Schlüter, Nils & Wiese, Frank, 2017, Late Cretaceous species of Vologesia (Echinoidea, Cassiduloida) from northern Spain, pp. 261-270 in Zootaxa 4306 (2) on page 267, DOI: 10.11646/zootaxa.4306.2.6, http://zenodo.org/record/843798, {"references":["Lambert, J. (1911) Etude sur les Echinides cretaces de Rennes les Bains et des Corbieres. Bulletin de la Societ d'Etudes scientifiques de l'Aude, 22, 1 - 120.","Christensen, W. K., Bilotte, M. & Hansotte, M. (1993) Additional Late Cretaceous belemnitellids from the Corbieres, French Pyrenees and ammonite biostratigraphy of the Santonian. Cretaceous Research, 14, 101 - 106. https: // doi. org / 10.1006 / cres. 1993.1008","Lambert, J. (1919) Echinides fossiles des environs de Santander recueillis par M. L. Mengaud. Annales de la Societ Linneenne de Lyon, Nouvelle Serie, 66, 1 - 32.","Smith, A. B. (1995) Late Campanian-Maastrichtian echinoids from the United Arab Emirates - Oman border region. Bulletin of the British Museum (Natural History), Geology, 51, 121 - 240."]}