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Factors Affecting Throughput in LTE :-

Factors Affecting Throughput in LTE :- Low mcs, Low sinr, Low rsrq , high prb usage, wrong earfcn Definition, no Carrier aggregation ör missing ca configuration, Pci , Route sequence index collision, Wrong tac planning, gateway security problem, etc. air quality (now sinr, rsrq, etc etc), modulation level. For example, 16QAM, 64QAM, etc. Low Throughput Issue:- 1 - Poor coverage (BLER) 2 - Availability issue 3 - Uplink Interference 4 - A poor RACH decoding SR 5 - High error on S1 link. 6 - Delay on S1 link towards MME & SGW. 7 - Accessibility issue. 8 - Handover failure. 9 - Lack of PRBs. 10 - Problematic UE. 11 - Downlink Interference (Bad CQI) 12 - MIMO Parameters 13 - High VSWR 14 - High radio errors or instability issue. 15 - Maximum number of RRC connections active per cell 16 - Maximum number of users per TTI supported per cell. 17 - Core network, MME/SGW, etc 18 - Transmission instability & bottleneck. 19 - Incorrect parameter setting. 20 - Badly tuned handover parameters...
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Mobile Station

      Mobile Station Subscribers communicate through the wireless network via the mobile station.  There are three types of mobile stations, including: ·         Vehicle mounted ·         Transportable ·         Handheld Each of these mobiles has a different output power associated with the specific classification.  The common classifications of mobiles and their corresponding output power vary according to type of GSM network.  The mobile class and output power for various GSM network applications are included in following Tables.  PCS-1900 Mobile Class and Power Class Peak Output Power (W) 1 2 2 1 3 .5  DCS-1800 Mobile Class and Power Class Peak Output Power (W) 1 1 2 .25  GSM-900 Mobile Class and Power Class...
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Capacity Calculations

     Capacity Calculations The capacity of a GSM-based network is dependent on the frequency reuse scheme and the amount of the operator’s spectrum.  Frequency reuse schemes are used to divide the spectrum into unique groups of channels, so that the frequency planner can methodically assign channels to a network of cells.  The reuse scheme is chosen to minimize the amount of interference in a network of cells, but also has an impact on the capacity of a particular site.  The amount of spectrum a license holder has must be considered as well.  Since the GSM channel is 200 kHz wide, five channels can fit into 1 MHz of spectrum.  Therefore, a European operator, with 25 MHz of spectrum, will have 62 channels available; whereas, a PCS operator in the United States , with 30 MHz of spectrum, will have 75 channels available.  Remember that half of the spectrum is for downlink and half is for uplink. A GSM market that has just launched commercial...
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Bursts in GSM

   Bursts Bursts are instantaneous transmissions of data over an RF channel, with voice or data information.  There are five types of burst in GSM which are defined as follows: ·         Normal – carries voice and control information. ·         Frequency Correction Burst – used for frequency synchronization. ·         Synchronization Burst – used for timing synchronization between base station and mobile station. ·         Dummy Burst – mixture of bits sent when there is not any other communications taking place on the BCCH. ·         Access Burst – used on access and handover where timing advance information is unknown. Each timeslot is divided into 156.25 bit periods, where every bit period is referenced to a bit number.  The first bit period is numbered 0 and the final .25 bit period is nu...
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