Tag Archives: CHANNEL

BCH ,CBCH and CCCH works in GSM

Broadcast Channels (BCH) Frequency correction channel (FCCH) the “lighthouse” of a BTS Synchronization channel (SCH) PLMN/base identifier of a BTS plus synchronization information (frame number)  Broadcast control channel (BCCH) to transmit system information 1-4, 7-8 (differs in GSM 900, GSM…

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,…

Spread Spectrum Concept

Dsss – Direct sequence spread spectrum DSSS – Direct Sequence Spread Spectrum is a spread spectrum technology in which original data is expand using PN code randomly to reduce noise and this also provide high security to data as is…

How Sub-Carrier Allocation in Wimax?

Sub-Carrier Allocation Mode 1 DL PUSC – Downlink partial Usage Sub-Channels The downlink PUSC replacement zone is unique, that must exist in the frame structure specified by the protocols. DL PUSC with all SC – PUSC with all sc indicates…

LTE Downlink & Uplink Physical Channel

LTE Downlink Physical Channel Physical Downlink Shared Channel ( PDSCH) This channel is used for unicastand paging functions. Carries the DL-SCH and PCH. QPSK,16-QAM,and 64-QAM Modulation. Physical Downlink Control Channel (PCSCH) Informs the UE about the resource allocation of PCH…

How Many LTE Downlink Transport Channel ? How its Work?

There are major four channel in LTE Downlink trasport channel. which list below with its work in short. Paging Channel ( PCH) Supports UE discontinuous reception (DRX) to enable UE power saving. Broadcasts in the entire coverage area of the…

What is inside SIM Card (Subscriber Identity Module) ?

Subscriber Identity Module (SIM) The SIM as mentioned previously is a “smart card” which plugs into the ME and contains information about the MS subscriber hence the name Subscriber Identity Module. The SIM contains several pieces of information: International Mobile…

How To Set Pilot Search Window Sizes in CDMA ?

When the handset first powers up, it does an exhaustive search for the best pilot. No windows are used in this process. On the paging channel, the handset learns the window sizes SRCH_WIN_A, N, R and uses them when looking…

Advantages of CDMA Handoff

It is “soft”, meaning that communication is not interrupted by the handoff. This is sometimes called “make before break.” This means fewer dropped calls for users and higher customer satisfaction for operators. The handoff is not abrupt, but rather it…

Handoff Candidate Classification in CDMA

The mobile station continuously searches for Pilots to detect the presence of other CDMA signals that have the same carrier frequency and measures the strength (received Ec/Nt) of the pilots.  When the mobile station detects a Pilot of sufficient strength…

Location Area Identity (LAI) and Global Cell Identity (GCI) in CDMA

Location Area Identity (LAI)  PAGING message is broadcast within a local area, the size of which depends on traffic, paging bearer capability, signaling flow , etc. Format:  MCC+MNC+LAC  MCC:  Mobile Country Code, 3 digits. MNC:  Mobile Network Code, 2 digits.…

How to Reverse Access Channel Work in CDMA?

Reverse Access Channel used by MS Initiate Communication or Respond to Paging Channel. A reverse channel is first spread with WALSH to 307.2Kbps and then becomes 1.2288Mcps after long code modulation. The long code here not only spreads spectrum, but…