From Introduction to EVDO: Physical Channels, Logical Channels, Network and Operation
Channels are the portion of a physical communications channel that is used for a particular communications purpose. There are two groups of channels used in the EVDO system; control channels and traffic channels. Control channels are used to setup, manage, and terminate communication sessions. Traffic channels are primarily used to transfer user data but can also transfer some control information.
Forward Pilot Channel
The forward pilot channel is a reference signal that is used to help the access terminal decode the received data. Access terminals also monitor the forward pilot channels of nearby access points to determine which access point the access terminal should be communicating with.
Unlike the IS-95 CDMA system that continually transmits a pilot channel, EVDO pilot channels are sent within bursts rather than continuously sent as a separate coded channel.
Forward MAC Channel
The forward MAC channel is used to provide information to the access terminal that can be used to coordinate how the access terminal establishes communication with the system (system access). This includes providing the status of the channel activity and how much power the access terminal is allowed to transmit.
Reverse Activity Channel
The reverse activity channel informs the access terminal of the channel activity so the access terminal can use this information to better coordinate when it attempts to access the system.
Reverse Power Control Channel
The reverse power control (RPC) channel is used by the access point to control the transmitter power level (fine tune) of the access terminal. This ensures...
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Topics of Interest
EVDO devices (also called access terminals) are data input and output devices that are used to communicate with a nearby access point. EVDO devices may or may not include removable user identity...
Channels are portions of a physical communications channel that is used to for a particular communications purpose. There are two groups of channels used in the CDMA system; control channels and...
Channel Structure Channels are a portion of a physical communications channel that is used to for a particular communications purpose. There are two groups of channels used in the WCDMA system;...
Channel Structure Channel structure is the division and coordination of a communication channel (information transfer) into logical channels, frames (groups) of data, and fields within the frames...
Analog Control Channel Analog control channels (ACC) are used for the transmission of control signaling information between a base station and a mobile radio. The types of information that is...
