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) Related content: What is Significance of Eb_No? What is a...
View ArticleWhat is the family of codes used for Chanelization in WCDMA?
Family of codes used for Chanelization in WCDMA used is Orthogonal Variable Spreading Factor.(OVSF) Related content: How much power usually a NodeB is allocated to control channels? Define Processing...
View ArticleWhat is the usage of Channelization code in downlink and uplink?
Uplink separation of physical data (DPDCH) and control channel (DPCCH) from same terminal. Downlink separation of downlink connections to different users within one cell. Related content: Simple...
View ArticleSimple definition of Pole Capacity
The pole capacity is the theoretical maximum capacity of the system. In WCDMA, this capacity is only theoretical since, once reached, the system goes in an instable state that leads to its collapse....
View ArticleWhen is System information sent to UE?
The system information is regularly broadcast to the UE on the BCCH. When a parameter in the system information is changed, all UE in a cell are notified by a paging message or by a system information...
View ArticleWhat are different Idle mode tasks UE performs?
In Idle mode, the UE has no connection to the radio network. Keeping UEs in Idle mode minimizes the use of resources both for the UEs and in the network. However, the UEs must still be able to access...
View ArticleWhat is cell selection criterion?
Cell selection is based on: Qmean: the average SIR of the target cell. Qmin: minimum required SIR. Pcompensation: a correction value for difference UE classes. S = Qmean – Qmin – Pcompensation If...
View ArticleWhat is Pilot Pollution?
Simply speaking, when the number of strong cells exceeds the active set size, there is “pilot pollution” in the area. Typically the active set size is 3, so if there are more than 3 strong cells then...
View ArticleCapacity Management and Its functions – WCDMA
Capacity Management is responsible for the control of the load in the cell. It consists of 3 main functions: 1. Dedicated Monitored Resource Handling: tracks utilization of critical resources of the...
View ArticleWhat is “noise rise”? What does a higher noise rise mean in terms of network...
For every new user added to the service, additional noise is added to the network. That is, each new user causes a “noise rise”. In theory, the “noise rise” is defined as the ratio of total received...
View ArticleHow many slots are there in a WCDMA Frame? How big is a frame in ms. how many...
WCDMA Frame is 15 slots wide. It is 10ms in length. There are 2560 chips in one slot. Chip rate is 3840 Kc/s Length of frame = 10 ms Number of chips in a frame = 3840 *10=38400 chips. Number of chips...
View ArticleDefine Active Set? Pros and Cons of having a small or longer Active Set
Active Set consists of group of cells that takes part in soft/softer handover & measure by UE. Typical size of Active set is 3 or 4 & generally a standard practice in all WCDMA networks. A...
View ArticleExplain Soft and Softer handover? Give some advantage and disadvantage for...
In Soft Handover, the UE connection consists of at least two radio links established with cells belonging to different RBSs. In Softer handover, the UE connection consists of at least two radio links...
View ArticleExplain Timer T3212?
Periodic LA and RA updating is used to notify the network of the UEs availability, and to avoid unnecessary paging attempts for a UE that has lost coverage and is not able to inform the CN that it is...
View ArticleWhat do you understand by DRX cycle?
The UE listens to the PICH only at certain predefined times, reducing power consumption. The periodicity of these searches is set by the system and the time interval is called Discontinuous Reception...
View ArticleHow many time Inner Loop Power Control happens and what type of fading it...
How many time Inner Loop Power Control happens and what type of fading it compensates? Answer:1500Hz and compensates Fast Fading. Related content: How much power usually a NodeB is allocated to control...
View ArticleWhat is Compressed Mode?
Compressed mode is a physical layer function that allows the UE to temporarily tune to another frequency, and measure the RF environment of another UMTS frequency (e.g. IFHO) or another technology...
View ArticleHow does UE camp (synchronize) to a NodeB?
1. UE uses the primary synchronization channel (P-SCH) for slot alignment (TS synchronization). 2. After aligning to NodeB time slot, UE then uses secondary synchronization channel (SSCH) to obtain...
View ArticleWhy Ec/Io is negative?
Pilot channel power is always less than the total cell power, the ratio of the Pilot power (Ec) to the total cell power (Io) is always less than one. Thus, when measured in decibels, the value of Ec/Io...
View ArticleDifference Between HLR and VLR
HLR vs VLR Home Location Register (HLR) and Visitors Location Register (VLR) are databases that contain the mobile subscriber information as per the GSM architecture. In general there is one central...
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