Tag: cdma

Power Control Required in Reverse link cdma due to following reason. Maximum System Capacity is Achieved if: All Mobiles are Power Controlled to the Minimum Power for Acceptable Signal Quality…

The forward link possesses many features that are specific to EV-DO, having been optimised for data transmission, particularly in the downlink direction. Average continuous rates of 600 kbps per sector…

A number of channels are transmitted in the forward direction to enable signalling, data and other capabilities to be handled. These channels include the Traffic channel, MAC channel, Control channel…

Each 20 millisecond frame in EIA/TIA-95-B CDMA is divided into sixteen “power control groups”. When the mobile transmits, each power control group contains 1536 data symbols (chips) at a rate…

The base station uses a slightly different scheme when the vocoder moves to lower rates. First, EIA/TIA-95-B CDMA base stations do not pulse their transmissions. Rather, base stations repeat the…

Voice data at 9600 bps or 14400 bps (full rate) is first passed through a convolutional encoder, which doubles the data rate for the 9600 bps case or increases it…

Vocoders Convert Voice to/from Analog Using Data Compression There are Three CDMA Vocoders: IS-96A  Variable Rate (8 kbps maximum) CDG  Variable Rate (13 kbps maximum) EVRC  Variable Rate (improved 8…

Uses Half-Rate Convolutional Encoder Outputs Two Bits of Encoded Data for Every Input Bit Unlike many digital cellular systems, CDMA provides powerful error correction to all voice data bits. This…

In an effort to provide CDMA with even greater voice quality, the CDG (CDMA Development Group) has proposed and implemented a new vocoder. This new vocoder uses and improved, higher…

All base stations digital transmissions are referenced to a common CDMA system-wide time scale that uses the GPS time scale, which is traceable to and synchronous with Universal Coordianted Time…