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FEC techniques are compared for different MIMO configurations of a high altitude, extremely wide bandwidth radio frequency downlink. Monte Carlo simulations are completed in MATLAB® with the aim of isolating the impacts of turbo codes and LDPC codes on system throughput and error performance. The system is modeled as a transmit-only static array at an altitude of 60,000 feet, with no interferers in the channel. Transmissions are received by a static receiver array. Simulations attempt to determine what modulation types should be considered for practical implementation, and what FEC codes enable these modulation schemes. The antenna configurations used in this study are [44:352], [62:248], and [80:160] transmitters to receivers. Effects from waveform generation, mixing, down-conversion, and amplification are not considered. Criteria of interest were BER and throughput, with the maximum allowable value of the former set at 1 x 10-5, and the latter set at a 1 terabits per second (Tbps) transfer rate for a successful configuration. Results show that the best performing system configuration was unable to meet both criteria, but was capable of improving over Brueggen's 2012 research, which used Reed-Solomon codes and a MIMO configuration of [80:160], by 18.6%. The best-case configuration produced a throughput rate of 0.83 Tbps at a BER of less than 1 x 10-8, by implementing a rate 2/3 LDPC code with QAM constellation of 16 symbols.

With this issue, the editors of the American Anthropologist introduce the first Contemporary Issues Forum, "Contested Pasts and the Practice of Anthropology." We find it incumbent upon the flagship journal of the profession to encourage productive discussion of current issues of relevance to anthropologists and the public. The editors have targeted broadly significant and controversial topics as foci for the forums with a view to encouraging productive dialogue. With this initial forum we open an arena for debate regarding anthropological practice and discourse and their consequences in the contemporary period of ethnic resurgence and (neo)colonial disempowerment. We recognize the debated nature of these issues and the potential importance of such controversies to the profession. Commentary on the forum papers from the readership of the American Anthropologist is welcome.

Intro -- Copyright -- Contents -- Figures -- Maps -- Tables -- Preface -- 1. Introduction: Ethnicity in Ancient Amazonia -- Part I: Archaeology -- 2. Archaeological Cultures and Past Identities in the Pre-colonial Central Amazon -- 3. Deep History, Cultural Identities, and Ethnogenesis in the Southern Amazon -- 4. Deep Time, Big Space -- 5. Generic Pots and Generic Indians -- 6. An Attempt to Understand Panoan Ethnogenesis in Relation to Long-Term Patterns and Transformation sof Regional Interaction in Western Amazonia -- Part II: Linguistics -- 7. Amazonian Ritual Communication in Relation to Multilingual Social Networks -- 8. The Spread of the Arawakan Languages -- 9. Comparative Arawak Linguistics -- 10. Linguistic Diversity Zones and Cartographic Modeling -- 11. Nested Identities in the Southern Guyana-Surinam Corner -- 12. Change, Contact, and Ethnogenesis in Northern Quechua -- Part III: Ethnohistory -- 13. Sacred Landscapes as Environmental Histories in Lowland South America -- 14. Constancy in Continuity? Native Oral History, Iconography, and Earthworks on the Upper Purús River -- 15. Ethnogenesis at the Interface of the Andes and the Amazon -- 16. Ethnogenesis and Interculturality in the "Forest of Canelos" -- 17. Captive Identities, or the Genesis of Subordinate Quasi-Ethnic Collectivities in the American Tropics -- 18. Afterword -- Contributors -- Index.

Investigating local Indigenous processes of creation and creativity, this book uses ethnographic and comparative anthropological perspectives to enquire about creative transformative practices in lowland South America. The volume shows how people create and reinforce their conditions of being by employing different genres of transgression and by creatively shifting contexts of significance. Local socio-cosmic orders, the interrelation of creative genres (myth, verbal art, song, ritual, and handicrafts), and their changing frames of reference (from communal celebrations to wider political and commercial realms) demonstrate the relational, generative, and processual quality of Amerindian creativity