Tag Archives: power control

Dedicated Control Channel (DCCH) in GSM

SDCCH (Stand-alone Dedicated Control Channel) Uplink and Downlink. Used for call setup, authentication, ciphering location update and SMS. SACCH (Slow Associated Control Channel) Downlink and Uplink. Used to transfer signal while MS have ongoing conversation on traffic or while SDCCH…

Forward Traffic Channel of CDMA

Forward Traffic Channel is used to Transmit Data and Signaling Information. Symbol repetition makes symbol streams at different rates adapted to those at the rate of 19.2k. The original symbol stream at  the rate of 19.2Kbps will not be repeated,…

Downlink Power control in LTE

The eNodeB determines the downlink transmit energy per resource element (lte epre). Downlink cell-specific reference-signal (RS) lte epre is constant across the downlink system bandwidth and constant across all subframes until different cell-specific RS power information is received. The downlink RS…

BCH,CCCH and DCCH Channel of GSM

BCH (Broadcast Channels) BCCH(Broadcast Control Channels) Downlink Only. Broadcast information of the serving cell (System Information). Transmitted on timeslot zero of BCCH carrier. Read only by idle mobile at least once every 30 secs. SCH (Synchronization Channels) Downlink Only Carries…

What is AMC & its Algorithm in LTE

The effective Eb/No and hence the spectral efficiency depend on BLER. However there are QoS requirements which also have to be considered. Taking both into account leads to a target BLER. AMC is in use in order to tune BLER…

GSM RF Optimization Step by Step

Here I write about GSM RF Optimization Step by Step and how to find KPI degradation and its solution. The RF network optimization process can be categorized by the following steps: Problem analysis Analyzing performance retrieved from tool reports and…

What is 3G? or WCDMA?

3G is new upgraded cdma technology, in simple word its Wide band Code Devision Multiple Access Technology (WCDMA). This is first technology in which video call possible means voice and data simultaneously transmitted and received between mobile or data card and…

LTE Downlink Logical Channel

Paging Control Channel(PCCH) A downlink channel that transfers paging information and system information change notifications. This channel isused for paging when the network does not know the location cell of the UE Broadcast Control Channel (BCCH) Provides system information to…

Specifications of WCDMA

Channel Bandwidth  5 MHz Duplex Mode  FDD and TDD Downlink RF Channel Structure  Direct Spread (DS) Chip Rate  3.84 Mcps Frame Length  10 ms Spreading Modulation  Balanced QPSK (downlink) Dual-channel QPSK (uplink) Complex spreading circuit Coherent detection  • User dedicated…

Main Characterictics of WCDMA

Support two basic modes: FDD and TDD modes High chip rate (3.84 Mcps) and data rates (up to 2 Mbps) Employs coherent detection on uplink and downlink based on the use of pilot symbols Inter-cell asynchronous operation Fast adaptive power…

Ranging in Wimax

Since each MS has a unique distance from the base station, it is critical in the uplink to synchronize the symbols and equalize the received power levels among the various active MSs. This process is known as ranging; when initiated,…

Types of Power Control in CDMA

Reverse power control Open loop power control Closed loop power control Inner loop power control:  800 Hz Outer loop power control Forward power control Message transmission mode: threshold transmission periodic transmission Closed loop power control    Reverse open loop power…