A microstrip coupler through a narrow slot in the common ground plane of a two-sided microstrip circuit board

1991 ◽  
Vol 4 (12) ◽  
pp. 543-547 ◽  
Author(s):  
C. C. Lin
2014 ◽  
Vol 8 (1) ◽  
pp. 109-115 ◽  
Author(s):  
Ali Akdagli ◽  
Abdurrahim Toktas

In this paper, a novel design of compact wideband multiple-input multiple-output (MIMO) antenna operating over a frequency range of 1.8–4.0 GHz at 10 dB is presented for mobile terminals. The MIMO antenna design consists of two symmetrical and orthogonal radiating elements with a small size of 15.5 × 16.5 mm2 printed on the corners of a mobile circuit board. The radiating element is composed of four meandered monopole branches with a strip-line fed by a probe. By triangularly trimming the corners of the common ground plane beneath the radiating elements, not only the mutual coupling is reduced, but also impedance bandwidth is increased. Although, the antenna in this form has sufficient correlation level between the radiating elements for MIMO operation, a novel design of plus-shaped parasitic element is inserted to the ground plane between those radiating elements in order to further enhance the isolation. The performance of the MIMO antenna is investigated in terms of s-parameters, radiation pattern, gain, envelope correlation coefficient (ECC), and total active reflection coefficient (TARC), and is verified through the measurements. The results demonstrate that the proposed MIMO antenna has good characteristics of wideband, isolation, gain, radiation pattern, and is compatible with LTE, WiMAX, and WLAN, besides it is small, compact, and embeddable in mobile terminals.


Author(s):  
Sarah E. Murray

This book gives a compositional, truth‐conditional, crosslinguistic semantics for evidentials set in a theory of the semantics for sentential mood. Central to this semantics is a proposal about a distinction between what propositional content is at‐issue, roughly primary or proffered, and what content is not‐at‐issue. Evidentials contribute not‐at‐issue content, more specifically what I will call a not‐at‐issue restriction. In addition, evidentials can affect the level of commitment a sentence makes to the main proposition, contributed by sentential mood. Building on recent work in the formal semantics of evidentials and related phenomena, the proposed semantics does not appeal to separate dimensions of illocutionary meaning. Instead, I argue that all sentences make three contributions: at‐issue content, not‐at‐issue content, and an illocutionary relation. At‐issue content is presented, made available for subsequent anaphora, but is not directly added to the common ground. Not‐at‐issue content directly updates the common ground. The illocutionary relation uses the at‐issue content to impose structure on the common ground, which, depending on the clause type (e.g., declarative, interrogative), can trigger further updates. Empirical support for this proposal comes from Cheyenne (Algonquian, primary data from the author’s fieldwork), English, and a wide variety of languages that have been discussed in the literature on evidentials.


Author(s):  
Deborah Tollefsen

When a group or institution issues a declarative statement, what sort of speech act is this? Is it the assertion of a single individual (perhaps the group’s spokesperson or leader) or the assertion of all or most of the group members? Or is there a sense in which the group itself asserts that p? If assertion is a speech act, then who is the actor in the case of group assertion? These are the questions this chapter aims to address. Whether groups themselves can make assertions or whether a group of individuals can jointly assert that p depends, in part, on what sort of speech act assertion is. The literature on assertion has burgeoned over the past few years, and there is a great deal of debate regarding the nature of assertion. John MacFarlane has helpfully identified four theories of assertion. Following Sandy Goldberg, we can call these the attitudinal account, the constitutive rule account, the common-ground account, and the commitment account. I shall consider what group assertion might look like under each of these accounts and doing so will help us to examine some of the accounts of group assertion (often presented as theories of group testimony) on offer. I shall argue that, of the four accounts, the commitment account can best be extended to make sense of group assertion in all its various forms.


2018 ◽  
Vol 52 (6) ◽  
pp. 2056-2079 ◽  
Author(s):  
DAVID LUNN

AbstractThis article investigates some of the institutional and poetic practices around the idea of Hindustani in the period 1900–47. It charts the establishment of the Hindustani Academy in 1927 and explores some of its publishing activities as it attempted to make a positive institutional intervention in the Hindi–Urdu debate and cultural field more broadly. It then considers some aspects of poetic production in literary journals, including those associated with the Academy. Ultimately, it is an attempt to explore the grey areas that existed between Hindi/Hindu and Urdu/Muslim in the pre-Independence decades, and to make the case for studying the literature of both traditions simultaneously, along with emphasizing that attempts at compromise—including the perennially contested term ‘Hindustani’ itself—must be taken on their own terms.


Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 539
Author(s):  
Ryan P. Tortorich ◽  
William Morell ◽  
Elizabeth Reiner ◽  
William Bouillon ◽  
Jin-Woo Choi

Because modern electronic systems are likely to be exposed to high intensity radiated fields (HIRF) environments, there is growing interest in understanding how electronic systems are affected by such environments. Backdoor coupling in particular is an area of concern for all electronics, but there is limited understanding about the mechanisms behind backdoor coupling. In this work, we present a study on printed circuit board (PCB) backdoor coupling and the effects of via fencing. Existing work focuses on ideal stackups and indicates that edge radiation is significantly reduced by via fencing. In this study, both full wave electromagnetic modeling and experimental verification are used to investigate both ideal and practical PCB stackups. In the ideal scenario, we find that via fencing substantially reduces coupling, which is consistent with prior work on emissions. In the practical scenario, we incorporate component footprints and traces which naturally introduce openings in the top ground plane. Both simulation and experimental data indicate that via fencing in the practical scenario does not substantially mitigate coupling, suggesting that PCB edge coupling is not the dominant coupling mechanism, even at varying angles of incidence and polarization.


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