Tag Archives: PAGING

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,…

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…

What is Work of Paging Channel in CDMA?

The paging channel transmits: System parameters message Access parameters Neighbors list CDMA channels list message The paging channel accomplishes: Paging to MS Assign traffic channel to MS The frame length of a paging channel is 20ms W1 ~ W7 are…

How Sync Channel work in CDMA?

A long code is used for scrambling. However, a long code has too long a period, which cannot be wholly used for scrambling. We can only sample some chips of a long code at some point of time and use…

What is Basic work of Pilot Channel in CDMA?

A pilot channel: Assist mobile station to be connected with CDMA network Handles multi-path searching Provide the phase reference for coherent demodulation and help the mobile station estimate the transmission power The mobile station measures and compares the pilot channel…

Transmit Diversity of CDMA

Diversity technology means that after receiving two or more input signals with mutually uncorrelated fading at the same time, the system demodulates these signals and adds them up. Thus, the system can receive more useful signals and overcome fading. A…