A. Players in the market
There are 3 main clusters of players in wireless industry.
i. Mobile-network operators
In the past, mobile-network operators were the ones that provided platforms, especially for cell phones. However, as Apple, Nokia, and RIM came up with their own platforms for cell phones, mobile-network operators are now facing a great challenge. Still, operating-systems companies
Wireless industry
Companies with an ability to transfer information over a distance without any additional electrical conductor or wires are considered to be in a wireless industry.
Players in the market
Mobile-network operators
Operating-systems company
Device makers
Current industry status
Apple is the leader. But companies like MS, Google are trying
Ⅰ. 무선 랜(무선LAN)의 개요
1. 무선 랜의 전파에 대해서
무선LAN은 전파를 사용하여 Data를 송수신 하므로 유선LAN에 비해 Noise에 영향을 받기 쉽다. 노이즈 영향을 피하게 위해서 [직접확산 스페트럼 확산 방식]이라는 통신방식을 사용한다. 이 방식은 군사용의 통신기술에 이용된 것으로 GPS(위치측정
In Korea, it is started with TU Media. 4 characteristics of satellite are as below.
New Media - Overcame the limitations time and place of existing broadcasters
Mobility - Can be connected anywhere through portable devices
Personal - Individual media
Multimedia - Can freely use the contents through voice, data and video and can be connected freely in cell phones and wireless Internet
Wireless Power Transmission: WPT)이다. 원래 유비쿼터스의 핵심 키워드 중에 하나가 바로 사라짐(disappearing)인데, 이는 그 개체로 가는 모든 선이 없음을 의미하며, 따라서 전력 공급선이 존재한다는 것은 큰 문제점으로 지적될 수 있다.
≪ … 중 략 … ≫
Ⅱ. 근거리통신망(랜, LAN)의 개념
최근