There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Catherine Durnell Cramton (\"The Mutual Knowledge Prob- conditions, the impact of organizational change on subsequent lem and Its Consequences for Dispersed Collaboration\") is Asso- performance and survival, and the consequences of organizational ciate Professor in the School of Management at George Mason structures and dynamics for employees\' careers and the compo- University. She recieved her Ph.D. in organizational behavior from sition of organizations\' work forces. She serves on the editorial Yale University. Her research explores the contemporary chal- boards of Organization Science, Administrative Science Quar- lenges of collaboration and leadership, including distributed work, terly, and the American Sociological Review. Address: Columbia interorganizational collaboration, project team leadership, and the University, Graduate School of Business, 706 Uris Hall, New impact of technology on collaboration. Address: School of Man- York, NY 10027-6902; telephone: (212) 854-4424; e-mail: agement, Mail Stop 5F5, George Mason University, Fairfax, VA hah15@columbia.edu . 22030-4444; telephone: (703) 993-1814; fax: (202) 318-4319; John C. Henderson (\"Understanding `Strategic Learning\': e-mail: ccramton@som.gmu.edu . Linking Organizational Learning, Knowledge Management, and Sue R. Faerman (\"Understanding Interorganizational Cooper- Sensemaking\") is the Richard C. Shipley Professor of Manage- ation: Private-Public Collaboration in Regulating Financial Market ment, Chairperson of the Information Systems Department, and Innovation\") is Professor of Public Administration and Organiza- Director of the Institute for Leading in a Dynamic Economy at tional Studies and Dean of Undergraduate Studies at the University Boston University\'s School of Management. He is a noted at Albany, State University of New York. Her research focuses on researcher, consultant, and executive educator with papers appear- the paradoxical nature of leadership and organizational perfor- ing in many refereed journals. His coauthored book, Knowledge mance. She received her Ph.D. in public administration from the Engine, examines leveraging a firm\'s knowledge assets. His University at Albany, State University of New York. Address: research interests include: managing strategic partnerships, impact Office of Undergraduate Studies-LC30, University at Albany, of the mobile Internet on markets and organizations, and knowl- State University of New York, 1400 Washington Avenue, Albany, edge management. Address: Boston University School of Man- NY 12222; telephone: (518) 442-3950; fax: (518) 442-4959; e-mail: agement, 595 Commonwealth Avenue, Room 546H, Boston, MA sfaerman@uamail.albany.edu . 02215; telephone: (617) 353-6142; fax: (617) 353-1695; e-mail: James F. Fairbank (\"Emulation in Academia: Balancing Struc- jchender@bu.edu . ture and Identity\") received his Ph.D. in management and organi- Giuseppe (Joe) Labianca (\"Emulation in Academia: Balancing zation, The Pennsylvania State University and is an assistant pro- Structure and Identity\") received his Ph.D. in management and or- fessor of management in the College of Business and Economics ganization, The Pennsylvania State University, and is an assistant at West Virginia University in Morgantown, WV. His current re- professor of organization and management at Emory University\'s search interests are strategic decision making and the management Goizueta Business School in Atlanta, GA. His primary interests are of information technology. Address: College of Business and Eco- in network and cognition research at the intra- and interorganiza- nomics, P.O. Box 6025, Morgantown, WV 26506-6025; telephone: tional levels. Recent projects have investigated the antecedents and (304) 293-7937; fax: (304) 293-5652; e-mail: ifairban@wvu.edu . consequences of disliking others in one\'s social networks at work, Dennis A. Gioia (\"Emulation in Academia: Balancing Structure as well as investigating the process of emulation between organ- and Identity\") is Professor of Organizational Behavior, Department zations. He conducts both quantitative and qualitative research, and of Management and Organization, Smeal College of Business Ad- has published in the Academy of Management Journal and Orga- ministration at The Pennsylvania State University. His current nization Science. He is currently serving on the editorial review research and writing interests focus primarily on the cognitive board of the Academy of Management Journal. Address: Goizueta processes of organization members, especially the ways in which Business School, 1300 Clifton Road, Emory University, Atlanta, identity, image, and reputation are involved in organizational GA 30322; telephone: (404) 727-7662; fax: (404) 727-6663; e-mail: sensemaking, sensegiving, and change. His work has appeared joe_labianca@bus.emory.edu . in many of the top journals in the field and he has coedited two David P. McCaffrey (\"Understanding Interorganizational Co- volumes of original contributions: The Thinking Organization operation: Private-Public Collaboration in Regulating Financial and Creative Action in Organizations. Address: Smeal College of Market Innovation\") is Professor of Public Administration, Public Business, Penn State University, 403 Beam BAB, University Park, Policy, and Organizational Studies at the University at Albany, PA 16802; telephone: (814) 865-6370; fax: (814) 863-7261; e-mail: State University of New York. His research focuses on the orga- dag4@psu.edu . nizational dynamics of regulatory systems. He received his Ph.D. Heather A. Haveman (\"Organizational Environments in Flux: in sociology from the State University of New York at Stony The Impact of Regulatory Punctuations on Organizational Do- Brook. Address: Department of Public Administration and Policy, mains, CEO Succession, and Performance\") is Professor of Man- University at Albany, State University of New York, 135 Western agement at the Graduate School of Business, Columbia University. Avenue, Albany, NY 12222; e-mail: d.mccaffrey@albany.edu . She received her Ph.D. in organizational behavior and industrial Alan D. Meyer (\"Organizational Environments in Flux: The relations from the Haas School of Business Administration at the Impact of Regulatory Punctuations on Organizational Domains, University of California at Berkeley in 1990. Her research inves- CEO Succession, and Performance\") is the Charles H. Lundquist tigates organizations\' responses to shifting internal and external Professor of Entrepreneurial Management at the University of

About Authors

A multiband handset antenna combining a PIFA and multiple slots on a ground plane is presented. It is shown by means of simulations that the slots on the ground plane have a double function: to tune the ground plane resonance at low frequencies (f ? 900 MHz) and to act as parasitic radiators at high frequencies (f ? 1800 MHz). A prototype is designed and built featuring a behavior suitable for low frequencies (GSM850 and GSM900) and for high frequencies spanning from DCS1800 to Bluetooth, and including, for instance, PCS1900, UMTS2000, and other possible systems. Reflection coefficient, efficiency, and radiation patterns are measured and compared with a design without slots to prove the advantages of the slotted ground plane. The component effect is investigated to determine critical areas where the placement is not recommended. Besides, the effect of the slot of the ground plane on SAR is investigated, by discussing the effect of the ground plane and slot modes for two phone positions. The total antenna volume of the proposed design is 40 × 15 × 6 mm3.

Multiband Handset Antenna Combining a PIFA, Slots, and Ground Plane Modes

A compact printed ultrawideband (UWB) monopole antenna with dual band-notched characteristics is presented. By inserting two I-shaped notches in both sides of the microstrip feed line on the ground plane, additional resonances are excited, and hence the bandwidth is increased up to 123%. Two notched frequency bands are achieved by embedding a pair of Γ-shaped stubs in the radiation patch and a modified G-slot defected ground structure in the feeding line. The designed antenna has a small size of 20 × 18 mm2 and operates over the frequency band between 2.8 and 11.8 GHz for VSWR <; 2, with one notch frequency band at 3.3-3.8 GHz (WiMAX band) and the other at 5.1-6 GHz (WLAN band). The VSWR and radiation patterns of the fabricated antenna are presented, which prove that the designed antenna is a good candidate for various UWB applications.

Compact Dual Band-Notched Printed Monopole Antenna for UWB Application

A simple direct-fed dual-loop antenna capable of providing hepta-band WWAN/LTE operation under surroundings of an unbroken metal rim in smartphone applications is proposed. The greatest highlight of this proposed antenna is that it provides a simple and effective multiband antenna solution for an unbroken metal-rimmed smartphone. The unbroken metal rim with 5 mm in height embraces the system circuit board of 130 $\, \times \,$ 70 mm $^{2}$ . Two no-ground portions of 10 $\, \times \,$ 70 mm $^{2}$ and 5 $\, \times \,$ 70 mm $^{2}$ are set on the top and bottom edge of the system circuit board, respectively. In-between the two separate no-ground portions, there is a system ground of 115 $\, \times \,$ 70 mm $^{2}$ connected with the unbroken metal rim via a small grounded patch which divides the unbroken metal rim into two strips. Finally, a dual-loop antenna is formed by combining the inner system ground and two strips. This proposed dual-loop antenna is capable of covering GSM850/900/DCS/PCS/UMTS2100/LTE 2300/2500 operating bands. Detailed design considerations of the proposed antenna are described and both experimental and simulation results are also presented and discussed.

A Dual-Loop Antenna Design for Hepta-Band WWAN/LTE Metal-Rimmed Smartphone Applications

The constant evolution of wireless handheld devices together with the apparition of multiple wireless communication systems fosters the antenna community to design new radiating and measurements systems capable of satisfying the market demands. It is an object of the present paper to provide an overview of the evolution that wireless handheld technology has experienced in the last years. In this sense, a description of the evolution of wireless handheld devices, regulations, challenges in today’s smartphones, and handset characterization is reviewed. Finally, recent advances in antenna technology for wireless handheld or portable devices are presented.

/pdf/advances-in-antenna-technology-for-wireless-handheld-devices-3q0sayjyh0.pdf

Advances in Antenna Technology for Wireless Handheld Devices

Technology and Intellectual Property Rights DepartmentFractusBarcelona, SpainS. KahngDepartment of Info. & Telecomm. Eng.University of IncheonIncheon, South KoreaAbstract—This research consists on a ground plane modiﬁcationusing slots of a PIFA (Planar Inverted F Antenna) handsetantenna with the objective to facilitate the integration of thefeeding transmission line which connects the antenna with the RF-module. Through this technique it is possible to obtain a multibandantenna while keeping the same antenna geometry, small volume

/pdf/multiband-handset-antenna-using-slots-on-the-ground-plane-4t1kj5twdy.pdf

Multiband handset antenna using slots on the ground plane: considerations to facilitate the integration of the feeding transmission line

The interaction between the human head and handset antennas needs to be taken into account, since mobile phones have to be functional, and, at the same time, guarantee biological compatibility. The present research analyzed the performance of several handset antennas with different slotted ground planes in free space and also in the presence of the human head. The main objective was to compare the measured bandwidth and efficiency in both environments (free space and human interaction), and the impact on the measured SAR (Specific Absorption Rate) of such antennas as functions of the slot configuration in the ground plane and the antenna's location. Results showed that slots may be useful for increasing bandwidth and efficiency while keeping similar SAR values compared to the non-slotted ground plane. Changing the antenna's location was a good way to achieve a significant SAR reduction. In some cases, when the antenna was at the lower edge of the ground plane (down position), the SAR could be reduced by a factor of two. Impedance, efficiency, and radiation patterns were measured and analyzed with a phantom head in order to understand the human head's effect on the antenna's performance. Although all antennas suffered from changes, shorted-end slots were more robust for human interaction than open-ended slots.

Analysis of the Human Head Interaction in Handset Antennas with Slotted Ground Planes

A technique consisting in designing the groundplane of a handset antenna is presented. The technique is applied to PIFA antennas to show how the bandwidth can be enhanced. Particularly, a dual-band PIFA operating at GSM900 MHz and GSM1800 MHz is expanded up to quad-band and hexa-band operation by means of groundplane design. Results for antenna efficiency show that the proposed technique can be applied to design multi-band antennas for handset phones.

/pdf/multiband-handset-antennas-by-means-of-groundplane-2sgcoe3t7y.pdf

Cristina Picher

Papers

Multiband Handset Antenna Combining a PIFA, Slots, and Ground Plane Modes

Advances in Antenna Technology for Wireless Handheld Devices

Multiband handset antenna using slots on the ground plane: considerations to facilitate the integration of the feeding transmission line

Analysis of the Human Head Interaction in Handset Antennas with Slotted Ground Planes

Multiband handset antennas by means of groundplane modification