UMTS Capacity Planning

To figure out the WCDMA network, we have to associate the several information. As WCDMA blockage can occur at several part also the multiple-service will consume different resource in the network. Furthermore the congestion in WCDMA is consisting of soft and hard blocking.To avoid the congestion and blockage of the service, we have to monitor the following resources 

OVSF (Channelization Code) Allocation

Users data is modulated by a channelization code. The orthogonality properties of OVSF enable the UE to recover its bits without being interfered by other users.  This is true only if the system is synchronous, which is the case in downlink, but not in uplink. Thus, the OVSF codes are not used to separate users in uplink and therefore different users can use the same code. But they can be used to distinguish the different physical channels of one user.
Channelization code is defined as Cch SF, k,, where, SF is the spreading factor of the code, and k is the sequence of code, 0≤k≤SF-1. Each level definition length of code tree is SF channelization code, and the left most value of each spreading code character is corresponding to the chip which is transmitted earliest.      SF = chip rate / symbol rate     so, high data rates = low SF code, and low data rates = high SF code.

Channel Element (CE) Resource

CE resources are a type of NodeB hardware resource. The number of CEs supported by single NodeB indicates the channel demodulation capabilities resource of the NodeB. The more CEs a NodeB supports, the more powerful the channel demodulation and service processing capabilities for serving the customers. Services at different rates require different numbers of CEs to ensure proper channel demodulation.

In a RAN, CE resources are managed by both the RNC and NodeB. The NodeB reports its CE capacity to the RNC. The RNC determines whether to admit a new service based on the number of CEs that need to be consumed and controls CE resources during CE congestion.