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How Many Different Methods to Combine OFDMA for handle Multiuser System?

Threre are four Different Methods to Combine OFDMA for handle Multiuser System. Plain OFDM: Normal LTE OFDM has no built-in multiple-access mechanism. This is suitable for broadcast systems like DVB-T/H which transmit only broadcast and multicast signals and do not really need an uplink feedback channel (although such systems exist too). Packet Statistical Multiplexing: It … Read more

Basic Modulation Techniques Wimax

Data bits modulate (modify) a carrier signal Basic modulation techniques: amplitude frequency phase. Data bits are represented over the transmission channel by SYMBOLS Symbol rate is expressed in Baud (Symbols per Second) Modulation of a carrier is used to transmit data bits efficiently over the air interface The modulation process creates modulation symbols. A modulation … Read more

How Header Compression in LTE

One of the main functions of the PDCP header compression is using Header Compression (ROHC) robust protocol defined by IETF (Internet Engineering Task Force) . In LTE, header compression is very important because there is no support for transport of voice circuit-switched (CS) domain. Thus in order to provide voice services (PS ) domain Packet … Read more

How Grouped UE Closed Subscriber

Closed Subscriber Group LTE supports the existence of cells which are only available for a limited set of EEC- A closed Subscriber Group (CSG). In order to prevent attempts to register on the UES CSG cells on which they do not have access to, up to the CSG supports white list, that is, a list … Read more

What is Principle for Frequency Planning in GSM

The actual frequency planning of certain areas is usually conducted with such areas divided into segments geographically, i.e., first divide a complex network into small networks. However, there should be some frequency carriers (when the frequency is enough) reserved at the boundary of the segments or the frequency carriers should be divided. Such boundary should … Read more

Multi layer Frequency Reuse Pattern in GSM

Multi-layer reuse pattern technology means to divide the whole frequency resources into different subgroups according to specific principles. Each subgroup allocates frequency carriers to every cell by means of different reuse models, so the reuse density of each frequency carrier as well as the interference will be different in each cell. The frequency carrier with … Read more

Frequency Planning Steps for GSM

Frequency Planning is possible by manually or automatic.At initial stage of new RF Network automatic frequency planned and then after for optimization based on KPI manual frequency planing done. Manual Frequency Planing Steps The steps to be followed in manual frequency planning are: Calculating the frequency reuse distance theoretically. Determining the cell repeat pattern Planning … Read more