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2. Information Access Devices

2.1 Handheld Computers Handheld computers comprise the largest group of Internet connectable pervasive devi

ces.

Currently two major operating systems are applied on handheld devices: Palm OS and Windows CE.

2.2 Palm OS-Based Devices Palm III models included infrared communication, version 3.0 of Palm OS and 2 MB o

f memory(1998).

Palm IIIx had 4 MB of memory, an improved display, and Motorola Dragonball EZ processor.

The Palm IIIc was the first Palm OS based device with a color display(2000).

The latest Palm devices are the Models m105, m130, m500, and m515. All of the models in this family have 8 MB memory size and can be distinguished by their design, screens and batteries.

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Palm application

The Address Book display a master list of addresses sorted by last name and displaying the principal phone numbers.

The Date Book is used to display and edit appointments in a daily, weekly or monthly view.

At the time the Memo Pad application is started, it first shows an index consisting of the first lines of the memos. If you tap on a list element, the complete memo is displayed.

With the Mail application users can read downloaded emails or generate new emails offline.

Glyphs can be drawn in a dedicated area below the screen. Glyphs are simplified characters, which can easily be interpreted by a simple handwriting recognition software called Graffiti.

The synchronization mechanism between a Palm OS based device and a desktop PC is HotSync.

The infrared port offers a convenient possibility to exchange data between different devices.

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AvantGo: 각종 웹사이트를 PDA 에서도 볼 수 있도록 변환해 주는 프로그램 Internet content can be downloaded by the AvantGo software installed on a PC. AvantGo offe

rs selected Web sites related to manifold topics, which are referred to as channels. Users can subscribe individually to particular channels of interest and receive updated content with every HotSync. The information is stored in HTML. The Web pages are compressed before they are transmitted to the Palm OS device.

AvantGo (Version 2.0 이후 ) is also possible to use AvantGo as an online Web browser. A proxy server at AvantGo.com modifies the Web pages in a way that they can be displayed on Palm devices.

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2.3 Windows CE-Based Handheld Computers

Windows CE requires plenty of memory and processing power making devices much more expensive.

While Palm concentrates on state-of-the-art mobile information management, Windows CE devices are technological wonderboxes, generously equipped with fancy hardware features.

PIM(Personal Information Management) application

ActiveSync is the synchronization software, which Windows CE applicxations use for keeping the mobile data consistent and up-to-date with databases on the user’s corresponding PC.

Most of today’s Windows CE devices in the field run the PocketPC version of Windows CE, which is tailored for handheld computers.

Part of PocketPC

Pocket Internet Explorer

Microsoft Media Player

Microsoft Reader

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2.4 EPOC Based-Handheld Computers

EPOC 은 이 세상이 " 개인적 편리의 신기원 (epoch)" 으로 들어가고 있다는 회사의 믿음으로부터 유래

EPOC is a versatile operating system designed for usage in various mobile devices.

EPOC has been developed by the Symbian consortium, founded by Ericsson, Motorola, Nokia, and Psion.

These devices contain a rich set of applications for mobile workers.

Symbian 은 EPOC 이 지원하는 하드웨어 종류를 " 무선 정보 장치 " 라고 부른다 . EPOC 은 펜 기반의 GUI 를 지원하는 32 비트용 , 멀티태스킹 운영체계이다 . 이것은 객체지향 설계를 사용하여 C++ 프로그래밍 언어로 작성되었다 . 코드는 작은 ROM 칩에도 들어갈 수 있도록 매우 간결하다 .

Symbian 이 선호하는 플랫폼은 ARM (Advanced RISC Machines) 아키텍처이다 . Symbian 은 ARM 이 와트당 MIPS 와 비용 측면에 있어 최적의 플랫폼이라고 여기고 있다 . Symbian 은 C++ 과 , BASIC 비슷한 언어인 OPL 그리고 자바 등을 위한 개발 도구도 제공하고 있다 .

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Comparing Handheld Computers

Device Class Palm Pocket PC EPOCA sample Product Palm i705 Casio E-200 Psion Series 5mx

OS Palm OS 4.1 PocketPC 2002 EPOC 32bit

Data Entry Stylus Stylus Keyboard

Display Size 7.8 cm 21 - 25 cm 11 - 14 cm

Display Resolution160 * 160 pixelsMonochrome or 256 colorTouch screen

320 * 240 pixels65000 colorsTouch screen

640 * 240 pixelsMonochromeTouch screen

RAM 8 MB 64 MB 16 MB

ProcessorMotorla Dragonball VZ33,33 MHz

Intel Strong ARM 1110,206 MHz

32 bit RISC ARM710T,36 MHz

Peripherals Serial, Infrared, Extension Card Slot

Serial, USB, Infrared, Compact Flash, Voice recording, Audio speaker

Serial, Infrared, Compact Flash, Voice recording

Applications PIM, Email, HotSync, Graffiti

PIM, ActiveSync, Handwriting, recognition, Internet Explorer, Office Suite, Pocket Outlook, Media Player

PIM, Email, Internet Browser, Database, Spreadsheet, WAP

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Palm i705 Casio E-200 Psion

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2.5 Sub-Notebooks

Sub-notebooks or Clamshells are somewhere in between a handheld devices and a regular notebook.

They have more memory, more CPU power and they provide a reasonable screen as well.

Sub-notebooks have much less computing power (than a regular notebook), cost less and they are intended for mobile usage.

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2.6 Phones

Modern phones create a high demand for new pervasive technologies.

A simple P2P voice interface powerful network clients

Fancy computing features like tiny hard disks and voice recognition are condensed into a tiny shell dissolving the demarcation to handheld organizers.

2.7 Cellular Phones

The operating systems used in cellular phones are quite manifold too. Mostly proprietary systems like RTOS from Siemens or GEOS from Geoworks are used. Others like EPOC are applied by several companies.

Global System for Mobile Communication (GSM)

Code Division Multiple Access (CDMA)

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2.8 Data Transmission Capabilities

The most important obstacle for this evolution is the speed of the data transmission itself: GSM Data currently allows only 9,6 kilobits per second, which is the bottleneck for wireless information retrieval.

General Packet Radio Service (GPRS) 115 kbps

Universal Mobile Telecommunication System (UMTS) 100 kbps – 2 Mbps

Mobile phones usually have an infrared port to exchange data locally with another device.

Bluetooth is a convenient approach to let multiple devices collaborate wireless with each other within a short distance of a few meters.

Phones, handhelds, and personal computer can be communicate with peripherals, like headsets or hard disks.

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2.9 Smart Phones

Smart phones combine a mobile phone with a handheld organizer into all-in one communication system.

Nokia Communicator 9110

GEOS operating system

Intel embedded 386 class processor with 24 MHz

4MB of RAM

Monochrome display (640 * 200 pixels)

GSM wireless communication

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The near future smart phones of all manufacturers will take advantage of high-speed wireless communication networks like GPRS and UMTS.

These devices will be able to exchange video and audio streams as self-evident as today’s SMS.

The MultiMobile is a smart phone prototype, developed by Siemens and Casio.

The MultiMobile can play MPEG-4 video files as well as MP3 audio files.

This devices can even be used for mobile video conferencing.

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2.10 Screenphones

Screenphones are the convergence of a phone and an Internet terminal.

The main goal of screenphones is to offer simple and convenient usage.

Screenphones can be used for simple information retrieval, for executing e-commerce web applications, emailing, etc.