In theory, multi-user MIMO is more immune to most of propagation limitationsrnplaguing single-user MIMO (SU-MIMO) systems, such as channel rank loss or an-rntenna correlation. However, in this thesis work, it has been considered the e ect ofrnantenna spacing on indoor multi-user MIMO sum-rate channel capacity at BS (basernstation) and user separation at UE (user equipment) side.rnThis can be analyzed by using correlation based-analytical approximation method,rnand its simulation results. These simulation results were obtained using MATLABrnsimulation tools. The simulation result shows the comparison of correlated MU-rnMIMO sum-rate channel capacity for all scenarios considered with non-correlatedrnstochastic channel capacity.rnBased on the result obtained it is better to use antenna spacing above 1rn2 (half-rncarrier wave length) to get optimum correlated sum-rate channel capacity in in-rndoor LOS compared to uncorrelated iid gaussian non-fading channel. In non-line ofrnsite(NLOS) MU-MIMO BC, antenna spacing from 1rn5 to 1rn2 is enough to get betterrnsum-rate channel capacity than other correlated channel compared to uncorrelatedrnRayliegh fading channel capacity. Similarly, using Ricean fading channels, it is bet-rnter to use antenna spacing above 1rn2 to get optimum sum-rate channel capacity.rnKEY WORDS: MU-MIMO, Indoor Scenario, Antenna Spacing, User separa-rntion, Sum-Rate Channel Capacity