improve DL/UL throughput in LTE & what are the causes for Poor DL/UL

How can improve DL/UL throughput in LTE & what are the causes for Poor DL/UL :

Throughput of cell mainly depends on CQI which is directly dependent on SINR.SINR depends on user number, bad dominant signal condition(RSSI),RSRP,RSRQ. So, improving the interference condition will lead to the better throughput. Throughput also depends on network latency. Also need to take into consideration your Carrier BW vs connected users/5MHz (anything over 65 users/5MHz leads to congestion), Overall DL/UL Spectral Efficiency, PRB Utilization%, PDCCH Usage, PCI Confusion, Overshooting cells, and Backhaul type/bandwidth.