Main article: Multi-user MIMO. Recently, results of research on multi-user MIMO technology have been emerging. While full multi-user MIMO (or network MIMO) can have a higher potential, practically, the research on (partial) multi-user MIMO (or multi-user and multi-antenna MIMO) technology is more active.
There are two ways to decline a call on the iPhone. 1  By pressing the Sleep/Wake button. 2  By tapping the 'Decline' button onscreen (appears only when the phone is unlocked, as you've mentioned)
To temporarily block caller ID and make a per-call âBlockedâ call, hereâs what you can do on the iPhone (or Android or any other phone): 1  Go to the Phone app numerical dialer screen. 2  Dial *67 before entering any other number on screen, it must prefix the number you will call. 3  Now enter the phone number as usual to dial, and proceed to call as usual.