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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 52, NO. 12, DECEMBER 2004

Fig. 3.  EVS Study. (a) Laptop surface and antenna surface, (b) realizable positions of antenna on laptop, (c) point representation of integrated position for book

keeping, (d) representation of plane waves illuminating the object, (e) representation of surface currents on the laptop surface confined by the antenna's surface,

and (f) ranking of position based on evaluation of EVS study.

electrical continuity), which is meant to mimic the computer's

(

for this study) and that of the antenna de-

[Fig. 3(a)]. A set of guidelines is then fol-

internal shielding. Future models may incorporate more mate-

fined by

lowed for the conformal integration scheme.

rials as well as a variety of different geometries with realistic

holes for devices, connectors, etc.

I.

For conformal integration, the antenna surface,

, must satisfy the physical restraints for

placement, and conformally occupy a surface on

IV. ELECTROMAGNETIC VISIBILITY STUDY

[Fig. 3(b)]:

For different positions on the laptop chassis, the effects of

edge diffraction from surface waves propagating to the neigh-

(1)

boring edges and corners of the structure should be considered.

However, in most cases these effects will not completely dic-

candi-

II.

Regions satisfying Guideline I create a set of

tate the performance of the antenna once mounted so they have

date locations  [Fig. 3(c)]

been left for future analysis of higher order effects. To better

understand the base relationship between antenna performance

(2)

and position, an EVS is considered as a first step for integration.

The EVS, which can be seen as a shortcut to a full modal and

III.

The laptop is discritized and illuminated by plane

diffraction analysis of the device, was first considered in [8] to

waves incident from all angles in the direction(s),

aid in the integration process of antennas onto laptop computers.

and/or orientation(s), most likely to receive/transmit

The motivation for the EVS is straightforward, and relies on the

data. For this study, the plane of incoming data is

fundamental relationship between the induced surface currents

considered to be in the azimuthal plane of the laptop

on the host device generated from incoming electromagnetic

. The laptop

computer [Fig. 3(d)] in the direction

fields and their impact on the antenna's performance. The study

is illuminated by plane waves propagating in the az-

works by locating suitable regions on the host chassis with the

at intervals of

(

imuthal plane

highest steady-state current, and translates them into regions of

for this study), for

. This produces a

visibility, from high to low, for the antenna. The process begins

plane waves (where

, and

total of

with the host surface (the laptop computer) defined by