How much power usually a NodeB is allocated to control channels?

The power allocated to control channels may depend on equipment vendor recommendation. Typically no more than 20% of the total NodeB power is allocated to control channels, including CPICH. However, if HSDPA is deployed on the same carrier then the total power allocated to control channel may go up to 25 to 30% because of the additional HSDPA control channels required.

What is a typical CPICH power?

CPICH power typically takes about 8~10% of the total NodeB power. For a 20W (43dBm) NodeB, CPICH is around 2W (35.1 ~ 33dBm).

In urban areas where in-building coverage is taken care of by in-building installations, the CPICH may sometimes go as low as 5% because:

1) The coverage area is small since users are close to the site, and

2) More power can be allocated to traffic channels

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What is the processing gain for 384 Kb/s service?

Processing Gain= 10 log (Chip rate /Bit rate)

=10*Log(3840/384)
=10*log (10)
=10*1
=10

Define Processing Gain for WCDMA?

Processing Gain is ratio between rate of spreaded signal and rate of non spreaded signal.
Processing Gain = 10 log (Chip rate /Bit rate)

What effect is there on signal by spreading and dispreading?

Spreading will increase the bandwidth of a as signal. A signal of 10 Kb/s will become 40 Kb/s after spreading and will become 10 Kb/s after despreading. The processing gain term expresses the gain achieved by spreading a narrow band signal over a wideband spectrum.

This gain is the ratio between the spreading chip rate and the actual service bit rate measured at the RLC level.

What is Significance of Eb_No?

Eb_No is related to QOS of a service which in terms related to bit error rate.
Technically it is the minimum signal to noise needed by infrastructure equipment after despreading it signal. This is a value used to compare different infrastructure vendors. Eb_No changes with the service type.

For AMR 12.2 is ~ 4db for Node B
For AMR 12.2 is ~ 8db for MS