MIMO means Multi Input and Multi Output. (Ito ung capability na pwede mkapagtransmit at mkasagap ng multiple spec/freq at any point of direction. Kung dati is point A is to A; B is to B and/or C is to C. Sa MIMO, pwede na ang A is to C, B is to A, C is to B and so on and so forth)
RSSI means Received Signal Strength Indicator (Jan makikita on how well your device can hear/read signals from Access Points. Kung sa mata pa ng tao yan, yan ung grado ng mata mo kung gano kalinaw. Kung 20/20 grado mo, kitang kita mo ung tinitingan mo kahit malayo. Kung malabo mata, so di msyadong kita ung tinitingnan mo. Ganun din sa signal)
Hit thanks if it helps!