How to Reverse Access Channel Work in CDMA?
Reverse Access Channel used by MS Initiate Communication or Respond to Paging Channel. A reverse channel is first spread with WALSH to 307.2Kbps and then becomes 1.2288Mcps after long code…
Telecom Techniques Guide
cdma technology optimization
Reverse Access Channel used by MS Initiate Communication or Respond to Paging Channel. A reverse channel is first spread with WALSH to 307.2Kbps and then becomes 1.2288Mcps after long code…
OVSF Code (Orthogonal Variable Spreading Factor) is used as channelization code Orthogonal codes are easily generated by starting with a seed of 1, repeating the 1 horizontally and vertically, and…
The paging channel transmits: System parameters message Access parameters Neighbors list CDMA channels list message The paging channel accomplishes: Paging to MS Assign traffic channel to MS The frame length…
A pilot channel: Assist mobile station to be connected with CDMA network Handles multi-path searching Provide the phase reference for coherent demodulation and help the mobile station estimate the transmission…
Diversity technology means that after receiving two or more input signals with mutually uncorrelated fading at the same time, the system demodulates these signals and adds them up. Thus, the…
Pilot Detection Threshold (T_ADD) Any Pilot that is strong but is not in the Handoff Direction Message is a source of interference. This Pilot should be immediately moved into the…
Downlink Physical Channel of WCDMA Downlink Dedicated Physical Channel: Downlink DPCH Downlink Common Physical Channel: Common Control Physical Channel (CCPCH) Synchronization Channel ( SCH) Paging Indicator Channel (PICH) Acquisition Indicator…
A physical channel is defined by a specific carrier frequency, code (scrambling code, spreading code) and relative phase. In UMTS system, the different code (scrambling code or spreading code) can distinguish the…
Channel Bandwidth 5 MHz Duplex Mode FDD and TDD Downlink RF Channel Structure Direct Spread (DS) Chip Rate 3.84 Mcps Frame Length 10 ms Spreading Modulation Balanced QPSK (downlink) Dual-channel…
Support two basic modes: FDD and TDD modes High chip rate (3.84 Mcps) and data rates (up to 2 Mbps) Employs coherent detection on uplink and downlink based on the…
How does WiMAX compare with the existing and emerging capabilities of 3G and Wi-Fi? The throughput capabilities of WiMAX depend on the channel bandwidth used. Unlike 3G systems, which have…