TelecomStudy18

What are the possible causes for a Drop Call on a UMTS network?               Poor Coverage (DL / UL)  Pilot Pollution / Pilot Spillover  Missing Neighbor  SC Collisions  Delayed Handovers  No resource availability (Congestion) for Hand in  Loss of Synchronization  Fast Fading  Delayed IRAT Triggers  Hardware Issues  External Interference

What are the possible causes for an Access Failure in UMTS?       ·          Missing Neighbors ·          Poor Coverage ·          Pilot Pollution / Spillover ·          Poor Cell Reselection ·          Core Network Issues ·          Non – availability of resources. Admission Control denies ·          Hardware Issues Improper RACH Parameters External Interference

What are the processing gains for CS and PS services? CS12.2:     25dB PS-64:       18dB PS-128:     15dB PS-384:     10dB HSDPA:      2dB

Basic Parameters of WCDMA Frequency Band                                      :            2100 MHz 1920-1980MHz (UL) &2110-2170 MHz (DL) Duplex Space                                         :            190 MHz Channel bandwidth                                 :            5 MHz Coding Spacing                                       :            200 KHz (RASTER) UARFCN Range                                        :            10562-10838 (Total ARFCN – 276) Duplex mode                                          :            FDD and TDD Downlink RF channel structure                  :            Direct spread Chip rate& Chips                                     :            3.84 Mcps& It is pulse of spreading spectrum n                                                                           It’s in rectangular shape of +1 & -1 Frame length                                         :            10 ms (38400 chips) = 15Slots, & 1slot = 2650chips