Signaling Channels -> carry user data

Key requirement for 3G: high-data rate.

The physical layer should be more efficient to do that.
In IS-95, the signaling information is carried by traffic(fundamental) channel.

In IS-2000, separate signaling channels are the option.

F-DCCH:
可以用來傳輸零星的SMS之類的Low-rate data 而不用浪費資源開一個CHANNEL
有兩種 20ms/5ms 的FRAME

Physical Layer

實體層控制BITS(被組織成FRAME)的傳輸
錯誤偵測和校正的FUNCTION也在此層被實做
MODULATION: 把BIT, WAVEFORM互轉換也是此層工作

CHANNELIZATION: 分別不同使用者的FUNCTION
(IS-2000/95都是用ORTHOGONAL和NEAR-ORTHOGONAL法分CHANNEL)

Signaling channel: 是指賦載訊號和控制的頻道 可以分為DEDICATED和COMMON兩種types (assigned給單一使用者或是SHARED)

User channel: for user information, voice, low-rate data (SMS) , high-rate (video streaming)
三種physical channels, F-FCH, F-SCCH, F-SCH(新的)

CDMA 2000 Architecture

架構分為三層

1. Physical layer:
Bits在空氣中的傳送接收
轉換訊號 提供bit/frame level的error control

2.1. Medium access control sublayer:
控制空氣中不同的使用者
實做analogous functions as a MAC entity以控制LAN
manages the access of different (low-speed voice and high-speed data) users to the shared air interface.
2.2. Signaling link access control sublayer:
提供可靠度

3. Upper layer:
負責整體IS-2000系統控制
It exercises this control by serving as the point that processes all and
originates new signaling messages. The information (both data and voice) messages
are also passed throughhere