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Types of Handover in LTE

Handovers are a crucial aspect of LTE networks, as they ensure seamless connectivity as mobile devices move within the network. Types of Handover in LTE What are the different types of handover in LTE? Intra-frequency Handover: Description: Intra-frequency handovers occur when a mobile device moves within the same frequency band and connects to a different … Read more

Processing Procedure of WCDMA System

Processing Procedure of WCDMA System Source coding can increase the transmitting efficiency. Channel coding can make the transmission more reliable. Spreading can increase the capability of overcoming interference. Through the modulation, the signals will transfer to radio signals from digital signals. Bit, Symbol, Chip Bit : data after source coding Symbol: data after channel coding … Read more

Forward Power Control in CDMA

Message Transmission Mode MS measures the frame quality and informs the base station to the result i.e. whether it is in the threshold or periodical  mode. Base station determines whether  to change the forward transmitting power or not. In IS-95 system, the forward power control is slow but in CDMA2000 system it is fast. Forward … Read more

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

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 that is not associated with the serving cell/sector, it sends a message to the serving … Read more

What is Cyclic prefix in LTE ?

The guard period after each rectangular pulse carrying the modulated data symbol is a simple and efficient method to deal with multi-path reception. The cyclic prefix (CP) simply consists of the last part of the following symbol. The size of the cyclic prefix field depends on the system and can even vary within one system. … Read more

Pulse shaping and spectrum in LTE

RF engineering is a trade off between: required radio spectrum (bandwidth), speed of data transmission (bit rates) and complexity of implementation. The pulse form used to modulate complex data symbols to the radio carrier frequency is the major element of this story. Over the years several pulse forms and their associated pulse shaping filters have … Read more

How Many CODES in CDMA?

There Are Three Codes in CDMA PN Long Code,PN Short Code & Walsh Code. PN Long Code The Long Code is a PN sequence that is 242 – 1 bits (chips) long. The long code is used to encrypt user information.  Both the base station and the mobile unit have knowledge of this sequence at … Read more

How Modulation-QPSK in CDMA ?

     In an actual application, the system implements the modulation in this way:  as shown above, I and Q channel sequences in the figure represent two channels of cyclic PN short code sequences.  The cyclic period of each channel of PN short codes is 215. For different sectors, there are different starting locations of I … Read more

CDMA Protocol Stacks

The original release of the EIA/TIA-95-B standard defined the protocol messages and formats to be used in the CDMA system. This release is know as Revision 0 of the IS-95 standard. Since the release of Revision 0, a newer standard has been released for cellular CDMA that is called the Revision A standard of IS-95. … Read more