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WCDMA vs CMDA2000
Major differences between WCDMA &CDMA2000 standards for CDMA-based 3G implementations:
Parameter | WCDMA | CMDA2000 |
---|---|---|
Carrier Spacing: spacing between |
CDMA operators to obtain channel protection | 5 MHz | 3.75 MHz | | Chip Rate : number of DSSS pulses per second; a chip is a pulse of DSSS code | 4.096 MHz | 3.68 Hz | | Spreading Factor : SF=(Chip Rate)/(Data Rate) | Higher | Lower | | Power Control Frequency : the output power of the transmitter is controlled by itself at this frequency | 1500 Hz | 800 Hz | | Frame Duration : the time duration of a frame;between beginning and end of the frame. | 10 ms | 20 ms (also uses 5, 30, 40 ms frames) | | Base Stations : base stations may or may not need synchronous timings | Asynchronous | Synchronous | | Forward Link Pilot : The pilot is a channel modulated only by the PN (Pseudo Noise) spreading codes | TDM, Dedicated pilot | CDM, Common Pilot | | Antenna Beam Forming : used for directional signal transmission & reception | TDM, Dedicated pilot | Auxiliary pilot |