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, 9.6Kbps symbol stream will be repeated once, 4.8Kbps symbol stream will be repeated twice…. Then, … Read more

How Common Control Channel (CCCH) works in GSM ?

RACH(Random Access Channel) Uplink only. Used by the MS when making its first access to the Network. The reason for access could be initiation of a call or a page response. AGCH (Access Grant Channel) Downlink only. Used for acknowledgement of the access attempt sent on RACH. Used by the network to assign a signaling … Read more

Categories GSM

What is Work of Paging Channel in CDMA?

What is Work of Paging Channel in CDMA?The Paging Channel in CDMA (Code Division Multiple Access) serves a crucial role in the efficient functioning of the communication system. As a dedicated control channel, the Paging Channel is responsible for transmitting important information, such as incoming calls and system messages, to mobile devices within a CDMA … Read more

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 them as the sequences of scrambling. This requires that a mobile station should know the following … Read more

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 powers from the base stations during the handoff Forward pilot channel is spread over W0 … Read more

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 mobile communication channel is a multi-path fading channel and any transmitted signal reaches a receive … Read more

What is T_ADD,T_DROP and T_TDROP in CDMA?

Pilot Detection Threshold (T_ADD) Any Pilot that is strong but is not in the Handoff Direction Message is a source of interference. This Pilot should be immediately moved into the active set for handoff to avoid voice/data degradation or a possible drop call. T_ADD affects the percentage of MS in handoff. It should be low … Read more

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 all mobile terminals connected to the eNodeB. A downlink channel for broadcasting system control information … Read more

List of Uplink and Downlink Physical Channel of WCDMA

Downlink Physical Channel of WCDMA Downlink Dedicated Physical Channel: Downlink DPCH Downlink Common Physical Channel: Common Control Physical Channel (CCPCH) Synchronization Channel ( SCH) Paging Indicator Channel (PICH) Acquisition Indicator Channel (AICH) Common Pilot Channel (CPICH) High-Speed Packet Downlink Shared Channel (HS-PDSCH) High-Speed Shared Control Channel (HS-SCCH) Uplink Physical Channel of WCDMA Uplink Dedicated Physical Channel: Uplink … Read more

Basic Work of WCDMA Physical Channel

A physical channel is defined by a specific carrier frequency, code (scrambling code, spreading code) and relative phase. In UMTS system, the different code (scrambling code or spreading code) can distinguish the channels. Most channels consist of radio frames and time slots, and each radio frame consists of 15 time slots. Two types of physical channel: UL and … Read more